AcknowledgementsHeart disease in tHe fire service

The IAFF Department of Occupational Health and Safety would like to thank those individuals who committed theirknowledge, talent and expertise to update the current edition of the manual:

• Stefanos N. Kales MD, MPH, FACP, FACOEM Associate Professor of Medicine, Harvard Medical School; Associate Professor & Director, Occupational andEnvironmental Medicine Residency, Harvard School of Public Health; and Division Chief, Occupational andEnvironmental Medicine & Medical Director, Employee and Industrial Medicine at the Cambridge HealthAlliance. Dr. Kales was funded during this project as a Principal Investigator by the US Department of HomelandSecurity- Federal Emergency Management Agency (FEMA) Assistance to Firefighters Grant (AFG) program’sawards EMW-2006-FP-01493 & EMW-2009-FP-00835.

• Albert Rielly MD, MPH Staff Physician in Occupational & Internal Medicine, Cambridge Health Alliance; Visiting Scientist, HarvardSchool of Public Health; Medical Examiner, Boston Fire Department.

• Special acknowledgment is given to the IAFF Division of Occupational Health, Safety and Medicine staffresponsible for coordinating the revision process and manual for their persistence in completing the directedresearch as well as the manual writing and organization of the project, including Jim Brinkley, Director ofOccupational Health and Safety, and IAFF Health and Safety Assistants Jason Atkins, Courtney Fulton, TheresaGorman, Ron McGraw, and Bart Siciliano. The Division’s administrative staff, especially Lisa Aaron and JoyceVanlandingham, were responsible for formatting of the final manual. In addition, IAFF Occupational MedicineFellows from Johns Hopkins School of Hygiene and Public Health provided valuable assistance. Initiated throughconvention action in 1986, the IAFF entered into a cooperative agreement with the Johns Hopkins UniversitySchool of Hygiene and Public Health to host physicians for 60-day rotations in their second year of post-graduatestudy specializing in occupation medicine. This publication represents another noted achievement of thisprogram.

General President General Secretary-TreasurerHarold A. Schaitberger Thomas H. Miller

Assistant to the General President for Occupational Health and Safety

Patrick J. Morrison

Director of Occupational Health and SafetyJames E. Brinkley

chapter 1 • introduction..........................................................................................................1

chapter 2 • Heart disease and the Occupation of fire fighting ........................................................3

chapter 3 • anatomy and function of the cardiovascular system ..........................................7

chapter 4 • diseases of the cardiovascular system..............................................................10

chapter 5 • risk factors for Heart disease ..........................................................................15

chapter 6 • Preventing Heart disease ..................................................................................24

chapter 7 • Heart disease and fire fighter Benefits ..............................................................32

Table of ContentsHeart disease in tHe fire service

The cardiovascular system consists ofthe heart and vessels (arteries, veinand capillaries) that circulate blood

through the body. The heart continuouslypumps blood through the vessels of thecirculatory system. If the heart stopsbeating and cardiopulmonaryresuscitation is not started within a fewminutes, serious brain damage and deathwill occur.i Cardiovascular diseases(CVD) are those diseases affecting thecardiovascular system, and thus, affect thefunction of the heart and/or the bloodvessels. CVD is common in the generalpopulation and is especially important tofire fighters and emergency medicalresponders because their jobs may exposethem to unique cardiovascular risks. Inparticular, fire fighting is recognized as ahazardous occupation.ii Although manypeople may assume that burns and smokeinhalation are the cause of most firefighter fatalities, CVD is actually thesingle most frequent cause of duty-relatedfatalities.iii CVD accounts for almost halfof all on-duty fatalities and for everyon-duty death from heart disease, thereare an estimated 17 non-fatal line of dutycardiovascular events in the U.S. fireservice.iv

Commonly, CVD is referred to as heartor cardiac disease. As shown in Figures1.1 and 1.2, heart disease is a major killerof both men and women in the generalpopulations of the United States and inCanada. Even though heart or cardiac disease is a

major cause of death, it can be preventedand treated. Moreover, increasedawareness of risk factors, such assmoking, hypertension and highcholesterol, and improvements indetection, treatment, and risk factorreduction have resulted in a decrease incardiovascular mortality since 1980.vii,viii

Recent cardiovascular mortality trendsfrom the United States and Canada arepresented in Figures 1.3 and 1.4.

1

Heart Disease in the Fire ServicecHaPter 1 • intrOductiOn

Figure 1.1v

Figure 1.2 vi

This manual is written for fire fightersand emergency medical responders, agroup of individuals who face specialrisks of cardiac disease or CVD. Themanual contains a review and an analysisof several topics, including the evidencethat fire fighters and emergency medicalresponders may be at increased risk fordeveloping heart disease, the normalanatomy and function of the heart, thetypes of diseases that afflict the heart, thefactors that increase fire fighters’ risk ofdeveloping heart disease, and what firefighters and emergency medicalresponders can do to prevent heartdisease. Information is also included thataddresses the Public Safety OfficersBenefits Program in the United States anda review of provincial and state heartlegislation.

The International Association of FireFighters knows you will find this manualto be informative and useful. n

2

Figure 1.3 ix

Figure 1.4 x

i van Lommel P, van Wees R, Meyers V, Elfferich I.Near-death experience in survivors of cardiac arrest: aprospective study in the Netherlands. Lancet.2001;358:2039-45.

ii Bureau of Labor Statistics, U.S. Department ofLabor, Occupational Outlook Handbook, 2010-11Edition, Fire Fighters, on the Internet athttp://www.bls.gov/oco/ocos329.htm (visitedSeptember 7, 2011).

iii Kales SN, Soteriades ES, Christophi CA, et al.Emergency duties and deaths from heart diseaseamong firefighters in the United States. N Engl J Med.2007;356:1207-1215.

iv Karter MJ, Molis JL. Firefighter Injuries. Quincy,MA. National Fire Protection Association; 2005.

v Heron M. Deaths: Leading Causes for 2007.National Vital Statistics Reports; vol. 59, no. 8.Hyattsville, MD: National Center for Health Statistics.2011.

vi Statistics Canada. 2010. Leading Causes of Deathin Canada, 2007. Catalogue no. 84-215-2010001.Table 2.

vii Ford ES, Ajani UA, Croft JB, Critchley JA,Labarthe DR, Kottke TE, Giles WH, Capewell S.Explaining the decrease in US deaths from coronarydisease, 1980–2000. N Engl J Med. 2007; 356:

2388–2398.viii Capewell S, Ford ES, et al. Cardiovascular risk

factor trends and potential for reducing coronaryheart disease mortality in the Unites States ofAmerica. Bulletin of the World Health Organization2010; 88:120-130. doi: 10.2471/BLT.08.057885.

ix Division of Vital Statistics, Age-Adjusted DeathRates for 113 Selected Causes: United States1999-2007. Table GMWK293R. National Center forHealth Statistics. Hyattsville, MD: National Center forHealth Statistics.2007.

x Statistics Canada. 2010. Mortality Summary List ofCauses. Catalogue no. 84F0209X1E.

3

Fire fighting is recognized as adangerous occupation. There areover one million North Americans

involved in carrying out this vital publicservice. Although many persons assumethat burns and smoke inhalation causemost on-duty deaths, as previouslymentioned, heart or cardiovasculardisease (CVD) is the single most frequentcause of duty-related fatalities among USfire fighters. CVD accounts for almosthalf of all fatalities, with 90% caused bycoronary heart disease (CHD).i, ii Inaddition, for every fatal on-duty heartdisease (HD) event, there are anestimated 17 non-fatal, line-of-duty CVDevents in the US fire service.iii Thischapter reviews the evidence regardingassociations between fire fighting as anoccupation and heart disease byexamining four areas: fire fighting andlifetime risk of CVD (cohort mortalitystudies); CVD as a proportion or fractionof deaths (proportionate mortality);strenuous duties as a trigger for acuteCVD events; and temporal variations inCVD events (circadian or dailyvariations). Strong evidence linking firefighting to heart disease events comesfrom the latter three areas with the mostrobust evidence deriving from studies inthe last decade linking specific fire serviceduties to very high risks of CVD deaths.

A) FIRE FIGHTER MORTALITY STUDIES

The method commonly used toinvestigate associations between a diseaseand a specific job is cohort mortalitystudy. A mortality study compares therisk of death from a disease, such ascardiovascular disease, in a group orcohort of people, such as fire fighters, to areference population. In a fire fighter CVD mortality study,

the number of deaths from CVD in agroup of fire fighters is compared to thenumber of CVD deaths from a referencepopulation. The result will be a ratio ofthe number of observed deaths in the firefighters compared to the number ofdeaths in the reference or comparison

population. The ratio is called astandardized mortality ratio (SMR). If astudy demonstrated that fire fighters hadincreased CVD deaths, the SMR would begreater than 1.0, and a statistical testwould indicate a 95% or greaterlikelihood of the result exceeding 1.0 forreasons other than chance variation. Oneimmediate weakness of this design is thatit does not count heart disease per se, butonly heart disease deaths. For example, ifa fire fighter developed CVD and retiredas a result, but later died from anotherdisease, that case would not be countedtowards heart disease in the mortalitystudy. On balance and taken together, cohort

mortality studies demonstrated two mainfindings. First, CVD or heart diseaseaccounts for about 35% of deaths amongfire fighters, which is similar to thegeneral population. Second, on balance,the average SMR for coronary heartdisease in fire fighters is about 0.9 or 10%lower compared to that of the referencepopulations.iv, v Haas et al.vi published areview of cohort mortality studies thatreported SMRs for fire fighters comparedto the general U.S. population. Althoughmost SMRs reported for coronary arterydisease were lower than the referencepopulation, one study found an SMRfrom heart disease of 1.99 for fire fighterswith over 30 years of service, which washigher than the reference population.These findings suggest the “healthy workeffect”, described below, may be maskingactual differences in CVD mortalityamong fire fighters. Ideally, the only difference between the

groups should be the exposure from firefighting, with both groups sharingcharacteristics of race, gender, lifestyle,etc. A typical comparison group for firefighters is the adult white malepopulation in North America. However,there are significant differences betweenthe general adult white male populationand fire fighters that can makeconclusions of mortality studies subjectto debate. One such difference that isoften observed in mortality studies is the“healthy worker effect” (HWE). TheHWE is a type of “bias” or error that

results in an observed decrease inmortality in workers when comparedwith the general population.vii There aremany sources of a potential HWE inmortality studies. For example, firefighters are selected for employment onthe basis of certain rigorous criteria.These include written tests, medicalexaminations and physical abilitiestesting. Many individuals in the generalpopulation with existing medicalproblems, disabilities, or who otherwisecannot meet the criteria are notnecessarily comparable to fire fighters. Asa result of this “selection bias”, firefighters as a group should be healthierthan the general population, and wouldbe expected to have a lower number ofdeaths from CVD than the generalpopulation that includes individuals whowork less demanding jobs, are notworking at all, as well as those withpre-existing medical illnesses.viii Thus, theHWE can mask excess mortality due toharmful exposures from firefighting. It isestimated that the HWE reduces theoverall death rate among workers toabout 80% of the rate in a referencepopulation.ix

Another weakness of previous studies isthey lack any information on individualfire fighters’ work exposures and personalrisk factors for CVD. These differencesamong individual fire fighters can alsoinfluence results of mortality studiesbecause exposure to potentialcardiovascular risk factors varies within agroup of fire fighters. For example, onefire fighter may have a significantlygreater exposure to hazards than anotherover the course of a career. Lackingcomprehensive exposure data, researchersuse duration of employment as a proxyfor exposure, so particular exposures thatmay cause increased mortality in aproportion of fire fighters would tend tobe underestimated in mortality studies.Finally, because most mortality studiesrely on information from deathcertificates, errors and/or inconsistenciesin the reported cause of death may resultin inaccurate heart disease death counts. In an effort to interpret conflicting

results of mortality studies, researchers

Heart Disease in the Fire ServicecHaPter 2 • Heart disease and tHe OccuPatiOn Of fire figHting

have re-analyzed results from priorstudies to ascertain if there is an increasedrisk of CVD mortality among firefighters. Choix took the results of 23previously published studies, of which 7showed positive evidence of increasedCVD mortality in fire fighters and 16 thatdid not, and tried to adjust for the HWE.After conducting a re-assessment, fourstudies which previously showed noincreased association between firefighting and cardiovascular mortalityunderestimated the occupational risk offire fighting and cardiovascular mortality.Choi concluded that overall, there isstrong evidence of an increased riskbetween work as a fire fighter and deathfrom cardiovascular disease.

B) FIRE FIGHTER PROPORTIONATEMORTALITY

Proportionate on-duty CVD mortalityrefers to the proportion, fraction orpercentage of deaths occurring in the lineof duty caused by heart and vasculardiseases. In this regard, there isunanimous agreement that fire fightersexperience the highest proportionatemortality due to heart disease in the lineof duty in comparison to otheroccupations.xi, xii Heart disease-relateddeaths cause roughly 45% of on-dutydeaths per year among fire fighters. Forlaw enforcement, construction,emergency medical services and alloccupations combined, the proportion of

on-duty deaths estimated to be due toCVD have been reported as 22%, 12%,11% and 15%, respectively.xiii, xiv Eventhough U.S. fire service deaths havedecreased since the 1970’s, unfortunately,the fraction or proportion due to heartdisease has remained consistently high(see Figure 2.1). More recent data showthat in 2011, sudden cardiac deathsaccounted for about 50% of line of dutyfire fighter fatalities.xv

Presumably, the high proportionatemortality observed in the fire service isexplained by the unique interaction offire fighters’ risk profiles and theexposures and stressors encounteredduring specific types of fire fightingduties (see strenuous duties below). Notsurprisingly, the risks of on-duty CHDevents vary widely across different duties;with the highest risks associated with themost strenuous tasks, while the lowestrisks are observed during routinenon-emergency or “downtime” situations(see strenuous duties section and Table 2.1).

C) STRENOUS FIRE FIGHTINGDUTIES AND TRIGGERING

Numerous studies have shown thatvarious types of strenuous situations (e.g.involving physical and or emotionalexertion) can trigger acute cardiovascularevents in individuals with underlyingdisease. In a similar fashion, periodicstressors in the general environment suchas surges in air pollutionxvi or influenza

activityxvii have been shown to precedespikes in CVD event rates within anexposed population. These heart eventsare largely confined to “susceptible”persons (the very young, the very old andthose who have known heart or lungdisease) within the larger group.In the last decade, a series of three

studies examined fire fighting duties inthis context by making educatedassumptions for the average annualprofessional time spent by fire fighters ineach type of fire service duty. Thisresearch provides definitive evidence thatcertain strenuous fire fighting duties canprecipitate or trigger heart disease eventsin fire fighters with underlying heartproblems.xviii, xix, xx These threeindependent investigations alldemonstrate very similar results for the“odds” or probability of heart diseaseevents for specific fire service duties whencompared to non-emergency situations(see Table 2.1). Together, the studies show markedly

significant increases in the likelihood ofheart disease events during firesuppression, alarm response and returnfrom alarms; and for heart deaths duringvigorous physical training exercises.Physical training included all job-relatedphysical fitness activities,physical-abilities testing, and simulated orlive fire, rescue, emergency, and searchdrills. The largest of the threeinvestigations, published by Kales,Soteriades ES, Christophi CA, et al.,considered all 449 on-duty deathsattributed to coronary heart disease(CHD) in the U.S. fire service for theperiod 1994-2004. The authors appliedthree different statistical analyses usingmodels that made varying assumptionsabout the length of time fire fightersspent on job duties to account forvariations due to volunteer/career status,rural versus urban areas and large andsmall jurisdictions. No matter whichmodel was used, the risks of CHD deathcompared to non-emergency situationsremained markedly elevated duringstrenuous duties compared tonon-emergency situations. In the mostdramatic example, although firesuppression represents only up to 5% ofannual professional time among firefighters, over 30% of on-duty CHDdeaths occurred during fire suppressionactivities. Thus, the study confirmed thatthe probability of a heart disease event is

4

Figure 2.1 xv

about 10 to over 100 times greater duringfire suppression than duringnon-emergency duties.xx

C) CIRCADIAN (DAILY) PATTERNSOF HEART DISEASE IN THE FIRE SERVICE

Another type of evidence from the sameresearchers also supports the assertionthat emergency duties can trigger orprecipitate heart disease deaths. Itexamines the circadian distribution of fireservice CHD deaths or how these deathsare distributed over the course of the24-hour day.xxi The researchers found thatthe daily pattern of fire service CHDdeaths mirrors the pattern of emergencyalarms and dispatches. Therefore, insteadof following the typical heart diseasepattern seen in the general population,where heart events peak in the morninghours, over two-thirds of line of dutyheart deaths in the fire service occurbetween the hours of noon and midnight(see Figure 2.2 below).

CONCLUSION

Taken together, published studies usingepidemiologic evidence to determine if arelationship exists between fire fightingand CVD mortality have not providedclear evidence of an increased risk ofCVD death when compared to thegeneral population. The most likelyexplanation is the “Healthy WorkerEffect”. While there may be debate if firefighters have little or no excess risk oflifetime heart disease mortality, there isrobust and compelling evidence that firefighters experience the highestproportionate on-duty mortality fromCVD of any occupation; accounting foralmost half of line-of-duty deaths.xxiii

Moreover, there is very strong evidencethat strenuous fire fighting duties cantrigger or precipitate on-duty heartdisease events. In particular, heart attacksand sudden cardiac deaths are 10 to over100 times as likely to occur during firesuppression activities compared tonon-emergency situations. Thus, thesefindings suggest an interaction betweenfire fighters’ heart disease risk factors andthe unique exposures they encounteron-duty in the fire service. n

Table 2.1

5

Duty Specific Risks of Heart Disease

Type of Duty Kales, Soteriades ES, Holder et al (Relative Kales et al (Relative Risk

Christophi CA et al Risk of Heart Event of CHD Death)xx

(Relative Risk of Leading to Retirement)xix

CHD Death)xviii

Fire suppression-OR (95% CI) 64.1 (7.4-556) 51 (12-223) 53 (40-72)

Physical training-OR (95% CI) 7.6 (1.8-31.3) 0.68 (0.2-2.7) 5.2 (3.6-7.5)

Alarm response-OR (95% CI) 5.6 (1.1-28.8) 6.4 (2.5-17) 7.4 (5.1-11)

Alarm return-OR (95% CI) 3.4 (0.8-14.7) 0.37 (0.07-1.8) 5.8 (4.1-8.1)

EMS and other non-fire 1.7 (0.5-5.9) 0.75 (0.3-1.8) 1.3 (0.9-2.0)

emergencies-OR (95% CI)

Firehouse and other non-fire 1.0 1.0 1.0

emergencies-OR (95% CI)

CHD indicates coronary heart disease; EMS, emergency medical service; OR, odds ratio, CI, confidence interval.

Figure 2.2 xxii

6

i. Fahy RF, LeBlanc PR, Molis JL. FirefighterFatalities in the United States – 2008. Quincy,MA: National Fire Protection Association; July2009.

ii. Kales SN, Soteriades ES, Christophi CA, et al.Emergency duties and deaths from heart diseaseamong firefighters in the United States. N Engl JMed. 2007; 356:1207–1215.

iii Karter MJ, Molis JL. Firefighter Injuries. Quincy,MA: National Fire Protection Association; 2005.

iv. Rosenstock L, Olsen J. Firefighting and deathfrom cardiovascular causes. N Engl J Med.2007;356:1261–1263.

v. Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review.2011;19:202-215.

vi Haas NS, Gochfeld M, Robson MG, et al. Latenthealth effects in firefighters. Int J Occup EnvironHealth. 2003;9:95–103.

vii. Choi B. A technique to re-assess epidemiologicevidence in light of the healthy worker effect:the case of firefighting and heart disease. JOccup Med. 2000; 42: 1021-1034.

viii. Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review.2011;19:202-215.

ix. Choi BCK. Definition, sources, magnitude,effect modifiers, and strategies of reduction ofthe healthy worker effect. J Occup. Med.1992;34:979-988.

x. Choi B. A technique to re-assess epidemiologicevidence in light of the healthy worker effect:the case of firefighting and heart disease. JOccup Med. 2000; 42: 1021-1034.

xi. United States Fire Service. Firefighter FatalityRetrospective Study. Arlington, VA, TriDataCorp: National Fire Data Center; 2002.

xii. Rosenstock L, Olsen J. Firefighting and deathfrom cardiovascular causes. N Engl J Med.2007;356:1261–1263.

xiii. United States Fire Service. Firefighter FatalityRetrospective Study. Arlington, VA, TriDataCorp: National Fire Data Center; 2002.

xiv. Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review.2011;19:202-215.

xv. Fahy RF. LeBlanc PR, Molis JL. FirefighterFatalities in the United States – 2011. Quincy,MA: National Fire Protection Association; June2012.

xvi Mittleman MA. Air pollution, exercise, andcardiovascular risk. N Engl J Med.2007;357:1147–1149.

xvii. Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review.2011;19:202-215.

xviii. Kales SN, Soteriades ES, Christoudias SG, et al.Firefighters and on-duty deaths from coronaryheart disease: a case control study. EnvironHealth. 2003;2:14.

xix. Holder JD, Stallings LA, Peeples L, et al.Firefighter heart presumption retirements inMassachusetts 1997–2004. J Occup EnvironMed. 2006;48:1047–1053.

xx. Kales SN, Soteriades ES, Christophi CA, et al.Emergency duties and deaths from heart diseaseamong firefighters in the United States. N Engl JMed. 2007; 356:1207–1215.

xxi. Kales SN, Soteriades ES, Christoudias SG, et al.Firefighters and on-duty deaths from coronaryheart disease: a case control study. EnvironHealth. 2003;2:14.

xxii. Fahy RF. LeBlanc PR, Molis JL. FirefighterFatalities in the United States – 2011. Quincy,MA: National Fire Protection Association; June2012.

xxiii. Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review.2011;19:202-215.

The cardiovascular or circulatorysystem consists of the heart andblood vessels responsible for the

vital function of transporting blood,oxygen and essential materialsthroughout the body necessary forsurvival. The following summary of theanatomy and function of the circulatorysystem may be helpful in appreciatinghow diseases of the heart and bloodvessels can lead to adverse healthoutcomes.

THE CIRCULATORY SYSTEM AND NORMAL HEART

The heart’s main function is to serve asa pump for blood that transports oxygenand essential materials throughout thebody. As Figure 3.1 illustrates, the hearthas four chambers: two upper chamberscalled atria and two lower chamberscalled ventricles. The right atrium receivesblood from the rest of the body and afterit fills with blood, it contracts to sendblood into the right ventricle. The rightventricle then pumps blood to the lungswhere it can pick up oxygen. Bloodreturning from the lungs enters the leftatrium where it is forced into the leftventricle. The left ventricle then pumpsout blood to the rest of the body whereoxygen can be delivered. The walls of eachheart chamber contain myocardium, atype of muscle that is unique to the heart.When myocardium contracts, blood isforced out of a chamber through one-wayvalves, that when functioning normally,prevent back-flow so the chamber can fillwith blood for the next heart beat.

HEART VALVES

Heart valves help ensure that the flow ofblood is one-way through each chamber,preventing back-flow that would decreaseheart output. The sounds from each heartbeat are generated from the closing ofthese valves. There are four heart valves;the tricuspid, pulmonary, mitral andaortic. The tricuspid valve separates theright atrium and right ventricle; the

pulmonary valve separates the rightventricle from the pulmonary artery;mitral valve separates the left atrium andleft ventricle; and the aortic valve

separates the left ventricle from the aorta.The locations of the heart valves inrelation to the rest of the heart can beseen in Figure 3.2.

7

Heart Disease in the Fire ServicecHaPter 3 • anatOmy and functiOn Of tHe cardiOvascular system

Figure 3.1i

Figure 3.2 ii

BLOOD VESSELS

The body has several types of hollow,tubular vessels that are used to carryblood. Arteries carry blood away from theheart to the tissues and contain musclesthat help control the relatively highpressure created when the left ventriclecontracts to send blood through the body.Arteries lead to capillaries, which have avery small diameter. Individual red bloodcells flow through capillaries in single file,allowing for oxygen exchange between redblood cells and tissue. Capillaries lead toveins that bring blood back towards theright side of the heart. Unlike arteries,veins have thin walls and are under lowpressure with blood flow dependent ongravity and pumping action from musclesin the arm and legs that press on the wallsof veins. Veins often contain one-wayvalves to prevent backflow of blood as it iscarried back to the heart.

MYOCARDIUM

The heart contains a special type ofmuscle, called myocardium. Myocardialcells contract and relax to generate thepressure necessary to pump blood.Individual myocardial cells are connectedvia intercalated discs to form long fibersthat form a lattice. The intercalated discsallow individual cells to communicate

with each other. Ions passing throughcells create an electric current thatreleases calcium inside the myocardialcells causing a synchronized contractionof myocardium. Myocardial cells requireoxygen to function and receive it throughspecial arteries, called coronary arteries.

CORONARY ARTERIES

The coronary arteries carry oxygen richblood from the left ventricle to supply themyocardium. There are two majorcoronary arteries, which supply differentareas of the heart. The right coronaryartery supplies the myocardium in theright ventricle and part of the leftventricle, and branches of left coronaryartery supply myocardium elsewhere inthe heart. Figure 3.3 illustrates the majorcoronary arteries. Commonly, a blockagein a coronary artery interferes withdelivery of oxygen to myocardium. Ifmyocardium does not receive enoughoxygen, it becomes ischemic (oxygendeprived), and if oxygen is deprived for along enough period of time, themyocardium will die or “infarct”. Thus,doctors refer to heart attacks asmyocardial infarctions or the endmanifestation of myocardial ischemiacaused by lack of oxygen in an area ofheart muscle.

CONDUCTION SYSTEM

As previously mentioned, the flow ofions between myocardial cells creates anelectrical current that triggers contractionof the heart muscle. To generate aneffective contraction of a chamber in theheart, myocardial cells must function in acoordinated manner. Specialized cells inthe sinoatrial node (SA node) of the rightatrium act as a pacemaker to establish therate at which the heart beats. These cellsgenerate the flow of ions that start thecontraction of the heart. From the SAnode, an electrical current spreadsthrough both atria, triggering acontraction and sends blood into bothventricles. The current is also carried tocells in the atrioventricular node (AVnode), which then transmit the currentinto the ventricles via dedicated cellscalled the AV bundle and Purkinje fibers.After a short delay, through these cells,the flow of ions is carried from the atriainto both ventricles to create asynchronized contraction. Figure 3.4illustrates the locations of thecomponents of the conduction system.

8

Figure 3.3 iii

Figure 3.4 iv

BLOOD PRESSURE (hg)

Blood pressure refers to the pressurewithin arteries generated by the heart’spumping. Blood pressure is reported inmillimeters (mm) of mercury. Forexample, a pressure of 20 mm means thata column of liquid mercury (Hg) wouldbe elevated 20 mm against gravity. Forclinical purposes, two values of bloodpressure are measured and recordedtogether, such as 110/70. The firstnumber, the systolic pressure, is ameasurement of the peak pressure in thearteries that occurs after the left ventriclecontracts to sends blood into the aortaand rest of the body. The second number,the diastolic pressure, is the restingpressure of the arteries. Blood pressure is determined by

multiple variables, such as the volume ofblood in the vascular system, force fromthe left ventricle contraction, and thediameter of arteries, which can becontrolled by contraction of muscles inthe arterial walls. The body hashomeostatic mechanisms to control theeffective circulating volume of fluid byaltering the rate of blood filtration andexcretion of fluid in the kidneys, andsecretes hormones that can alter dilationof blood vessels and change the force ofheart contractions.

A DYNAMIC SYSTEM

The circulatory system has homeostaticmechanisms in place to respond toconditions requiring increased work tokeep the tissues of the body supplied withoxygen. This can include, but is notlimited to increased physical exertion,strong emotions, pain and illness. Theheart can respond to signals from thenervous system and chemical messengerslike epinephrine to change the rate ofcontraction, force of contraction oramount of blood pumped out of the leftventricle with each contraction. Similarly,the arteries and veins can changediameter that can alter blood pressure. Ifarteries decrease in diameter, the bloodpressure will increase and conversely, ifthe diameter of arteries is increased,blood pressure will fall. Additionally,medications can interact with this system.

CONCLUSION

The circulatory system is composed ofthe heart and associated vessels thattransport blood, which carries oxygenand essential materials throughout thebody. These components form a dynamicsystem that can respond to multipledemands on the body by alteringvariables like heart rate, blood pressure,effective circulating volume of blood andmyocardial contractility. The brain andother vital organs depend on the properfunction of the circulatory system forsurvival, making circulatory healthcritically important. n

9

i, ii, iii, iv From The Merck Manual Home Health Handbook, edited by Robert Porter. Copyright 2010-2011 by Merck Sharp & Dohme Corp., a subsidiary of Merck &Co., Inc., Whitehouse Station, NJ. Available at: http://www.merckmanuals.com/home/index.html. Accessed (3/31/12).

The heart is responsible for a variety ofessential functions in order to ensure life.Various anatomic components of thecardiovascular system described in thepreceding chapter are subject to diseaseprocesses that can disrupt normalphysiology and health. This chapterreviews the most common diseasesaffecting the cardiovascular system.

DISEASES OF THE CORONARY ARTERIES

The coronary arteries supply themyocardium with oxygen and essentialnutrients. The most common diseaseprocess that can interrupt the flow ofblood through the coronary arteries isatherosclerosis. Atherosclerosis is adisease of the arteries caused bydeposition of cholesterol plaques on theinner lining of the arteries causingnarrowing and altering of blood flowthrough the artery. It is the underlyingcause for most heart attacks and strokesoccurring in the United States andCanada. Narrowing of the coronaryarteries from atherosclerosis is referred toby different interchangeable terms, suchas coronary heart disease (CHD),coronary artery disease, ischemic heartdisease, atherosclerotic coronary vasculardisease, or atherosclerotic heart disease.CHD is the preferred term and will beused here. CHD accounts for 90% ofon-duty heart disease deaths among U.S.fire fighters.i

The wall of an artery is composed ofseveral layers. Figure 4.1 depicts thenormal layers of an artery. The innermostlayer is one cell layer thick and is calledthe endothelium. The endothelium linesthe inside of the artery and is in contactwith blood cells. Atherosclerosis starts with damage to

endothelial cells, which can occur fromfluid shear forces at locations where bloodundergoes sudden changes in velocity anddirection. After the injury to the cells,platelets and clot forming proteins form ablood clot at the site of the damage. Overtime, the body removes the clot andrepairs the damage to the endothelium.However, smooth muscle and other body

10

Heart Disease in the Fire ServicecHaPter 4 • diseases Of tHe cardiOvascular system

Figure 4.1 ii

Figure 4.2 iii

cells can enter the area. The area ofcellular infiltration leads to deposition ofcollagen and lipids like cholesterol, whichis called an atherosclerotic plaque oratheroma. The atheroma is graduallycovered with endothelial cells, but thisarea of endothelium is prone to repeatinjury. Smoking, high blood pressure,excessive dietary fat, and other insults tothe cardiovascular system can cause theatheroma to grow, narrowing the artery,which is also known as stenosis. Thisprocess is illustrated in Figure 4.2.The formation of atherosclerosis is

gradual, and years can pass before anindividual develops symptoms related tonarrowing. This process may beaccelerated by lifestyle and occupationalexposures, but it can also be influencedfavorably by lifestyle and other riskreduction methods as illustrated in Figure4.3. The final end stage outcomes ofnarrowed or atherosclerotic arteriesinclude angina, which is chest pain ordiscomfort that occurs when an area ofthe heart is deprived of oxygen, a heartattack or sudden death, which can betriggered by strenuous firefighting dutiesin a person with underlying disease.Examples of less common manifestationsinclude fainting, chronic fatigue,shortness of breath, and an abnormalelectrocardiogram (EKG). A common method of identifying

coronary arterial narrowing is an exerciseor other types of stress tests. In the morecommon treadmill exercise tests, thesubject walks on a treadmill through aseries of stages that progress throughincreasing speed and grade or incline ofthe treadmill, while having the heart’ssignals recorded by an EKG. A maximaltreadmill test can obtain several differenttypes of important information. Thelonger the time one is able to continueexercising on a treadmill protocol, thehigher that person’s aerobic capacity orphysical fitness level. Higher fitness levelsare associated with a better prognosis(long-term outcomes) and thus,decreased risks for death from bothcardiovascular and non-cardiovascularcauses. Additionally, if the stress testshows a result consistent with a lack ofoxygen in myocardial cells, which isreferred to as ischemia, the location andextent of coronary arterial narrowing canbe assessed by other tests. The goldstandard for this is the cardiaccatheterization. A cardiologist performs a

cardiac catheterization by passing a smalltube into the coronary arteries andinjecting contrast material that is opaqueto X-rays. Under fluoroscopy, the contrastmaterial will reveal any narrowing orblockages of the coronary arteries. Ifpossible, the cardiologist can try toincrease the diameter of a narrowed orblocked artery with angioplasty (with orwithout placing a stent) to restore bloodflow. A less invasive alternative to thecatheterization is a CT-angiogram, whichprovides similar views of the heart andcoronary arteries by combiningcomputerized tomography (CT) withspecial vascular contrast material.

ANGINA

Chest pain, or angina, can occur whennarrowing of the coronary arteries resultsin inadequate flow of blood to themyocardial cells. Sensory pain fibers inthe heart are stimulated by ischemia, or alack of oxygen in myocardial cells. Unlikepain fibers in the skin, pain fibers in theheart do not cause localized, sharp pain.Classically, the chest pain that occurswhen the heart is not receiving enoughblood is described as sub-sternal“pressure” that may radiate into the neckand arms. However, many people may notexhibit the classic symptoms of angina,even though there is severe narrowing ofthe coronary arteries. These persons may

experience shortness of breath andfatigue without pain.Angina may be stable, meaning it can be

predictably brought on and relieved by acertain level of exertion, and the chestpain that occurs does not necessarilymean that a heart attack is occurring orimpending. For example, someone withlong-standing narrowing of a coronaryartery may feel well at rest because thesupply of blood is sufficient. However,with a physiologic stress on the heart,such as from exertion or strong emotion,the heart will attempt to increase theheart rate or force of contraction. Inorder to accomplish this task, themyocardial cells have to work harder andrequire an increased supply of blood. Ifthe narrowing of the artery prevents thisadditional blood flow, the cells willbecome ischemic and angina will occur. Ifthe individual is able to rest, themyocardial cells do not have work as hardand the flow of blood again becomesadequate and pain resolves. In the case ofstable angina, the pain will resolve withina few minutes of initiating rest.In unstable angina, the pattern of pain is

no longer predictable. Symptoms canstart occurring with mild exertion, morefrequent exertion, or even complete rest,and typically can worsen precipitously.Unstable angina often indicates therupture of an atherosclerotic coronaryartery plaque and/or presence of a clot

11

Figure 4.3 iv

that acutely decreases blood flow.Unstable angina or acute coronarysyndrome can lead to an infarction orheart attack and even death (see below)and is a true medical emergency.

HEART ATTACK

A heart attack or myocardial infarctionis a common clinical manifestation ofCVD. A heart attack most commonlyoccurs when a coronary artery is severelyor completely narrowed by a blood clot. Aruptured atheroma is often implicated. Aplaque that ruptures and disrupts theendothelium is very thrombogenic,meaning that clots can form quickly onthe exposed surface of a plaque and blockan artery. This is illustrated in Figure 4.4.If a heart attack occurs, the myocardial

cells supplied by the artery will becomeischemic and chest pain will occur, even ifthe person is at rest. If the flow of blood isnot restored within 10 to 15 minutes,myocardial cells will start to die or infarct.The amount of myocardium that diesdepends on the location of the arteryinvolved. With the death of myocardialcells, normal heart function will bedisrupted. Common complications of aheart attack are death, heart failure andarrhythmias. After a heart attack, deadmyocardium is replaced by scar tissue.The scar tissue does not contract and theusual synchronized contraction of theheart may be diminished to the pointwhere the heart cannot pump enoughblood to the rest of the body, a conditiontermed heart failure. If the area of deadmyocardium included the specialized cellsresponsible for generating or conductingthe electrical current necessary for theheart to contract, an abnormal heartrhythm, or arrhythmia, can occur.

SUDDEN DEATH

In the case of sudden cardiac death, aperson will suddenly collapse and quicklydie from cessation of blood flow in thecirculatory system. One mechanism issudden clot formation in an area of thecoronary arteries that blocks much of theheart’s blood supply therefore causing theheart to stop beating. Anothermechanism is an abnormal heart rhythmoriginating from the ventricles(ventricular tachycardia, or fibrillation)that does not allow the heart to generateeffective contractions so that bloodcannot reach the brain and other vitalorgans. In either circumstance, the lack ofblood flow to the brain causesunconsciousness within seconds anddeath within minutes.

OTHER DISEASES OF THECORONARY ARTERIES

There are other less common disordersthat can cause blockages of the coronaryarteries. However, these conditions arerelatively less common and not associatedwith exposures typically encounteredwith firefighting. These includecongenital abnormalities, coronaryvasospasm, vasculitis, large dosing ofionizing radiation, and blunt trauma tothe chest.

DISEASES OF THE HEART MUSCLE(CARDIOMYOPATHY)

Diseases of the myocardial cells are termedcardiomyopathies. The cardiomyopathiescan be organized into categories; congestive,hypertrophic and restrictive. Figure 4.5shows how myocardium in the ventricles ofthe heart can appear for each of thecardiomyopathies compared to a normalheart.

DILATED (OR CONGESTIVECARDIOMYOPATHY

Conditions that damage, but not kill,myocardial cells can impair effective heartcontractions. If enough of themyocardium is affected, the heart willbecome dilated and the chambersoverfilled with blood as the heart is not asefficient in pumping blood. Persons withdilated cardiomyopathy can present withclinical signs of heart failure. The mostcommon causes of dilatedcardiomyopathy are heart damage due toprevious heart attacks, various viralinfections, alcohol abuse, valvular heartdisease and chronic uncontrolledhypertension (high blood pressure).

HYPERTROPHICCARDIOMYOPATHY

This condition has not been associatedwith any occupational exposures. It istriggered by an abnormal growth ofmyocardium that is caused by a geneticabnormality. The abnormal growth ofmuscle can create an eccentrichypertrophy involving the septum of theheart. This growth of heart muscle canlead to an outflow obstruction of blood inthe heart, causing heart failure and fatalarrhythmias. This obstruction may beassociated with a heart murmur.

RESTRICTIVE CARDIOMYOPATHY

This type of cardiomyopathy has notbeen linked to any occupationalexposures. It is caused by an inability ofthe myocardium to adequately relax,impairing filling of heart chambers thatnormally occurs between heart beats,compromising cardiac output. The wallsof the myocardium become stiff, oftenfrom infiltrative diseases such assarcoidosis, or cancers such asamyloidosis.

LEFT VENTRICULARHYPERTROPHY

Left ventricular hypertrophy (LVH)refers to a concentrated growth ofmyocardium in the left ventricle inresponse to having to chronically workharder to pump blood. It may resemblehypertrophic cardiomyopathy describedabove. It most commonly occurs inindividuals who have chronic, untreated

12

Figure 4.4 v

hypertension. Because the hypertrophiedcells have to work harder, they require anincreased blood supply and may be moresusceptible to adverse outcomes of CVD,including heart attacks and sudden death.A review of fire fighter autopsiesdemonstrated that close to 60% ofon-duty deaths caused by heart diseasehad evidence of LVH.vii

DISEASES OF THE HEART VALVES

Firefighting has not been linked withany increased risk of developing valvularheart disease. Heart valves may becomedamaged by infection, congenitalabnormalities or degenerative damagewith time. The most common problemsare valvular stenosis and insufficiency.Stenosis means a valve cannot opencompletely and insufficiency means that

the valve cannot close completely. In bothcases, the heart must work harder topump blood. In the case of stenosis, theheart must generate an increased force ofcontraction to push blood through thesmaller opening. In insufficiency, theefficiency of the pump is impaired as lessblood is pumped out with each beat, sothe heart must work harder to force outthe same amount of blood as it did beforethe valve began to leak. Both valvularstenosis and insufficiency can lead toheart failure.

MITRAL VALVE PROLAPSE

Mitral valve prolapse has not beenassociated with firefighting oroccupational exposures. It is caused by anabnormal mitral valve that does not closenormally and as a result pushes back, or

prolapses, into the left atrium duringcontraction of the left ventricle. Thiscondition may cause a heart murmur,chest pain that is unrelated to narrowingor occlusion of the coronary arteries, andabnormal heart beats. However, mostindividuals with this condition do notexperience any symptoms, do not requiretreatment and can lead a normal life.

INFECTIOUS ENDOCARDITIS

This condition has not been associatedwith fire fighting. It is caused by infectionof the heart valve. Persons with some typeof underlying valvular abnormality are athigher risk. It is also associated with illicitintravenous drug use. More recently, ithas also been found to occur inassociation with intravascular devices andprocedures.viii It can lead to destruction ofthe valve and infective particles can beseeded to the rest of the body via theblood. Some of these infected particlescan create blockages that can obstructblood vessels elsewhere in the body. Forexample, a blockage, or embolism to anartery in the brain could cause a stroke.

DISEASES OF THE CONDUCTION SYSTEM

As mentioned in the previous chapter ofthis manual, the heart containsspecialized cells that are responsible forgenerating and conducting electricalcurrent throughout the heart to maintainsynchronized contraction of the heartchambers to pump blood effectively. Themore serious disorders of the conductionsystem are reviewed below.

ARRHYTHMIAS

An arrhythmia is an abnormal transferof electrical current through the heart’sconduction system. Multiple causes ofarrhythmias exist, often an abnormal areaof heart tissue acts as a focus for theaberrant conduction, such as ischemiccells or scar tissue. Very severe heartfailure is also a risk factor forarrhythmias. Arrhythmias can involvefaulty conduction of current in allchambers or only the ventricles or atria.An arrhythmia can lead to very slow heartrates (bradycardia) or fast heart rates(tachycardia). Tachycardia may cause theheart to beat at rates in excess of 150 beatsper minute. The heart may not be able to

13

Figure 4.5 vi

keep pace in terms of refilling with bloodand pumping the blood effectively at suchhigh rates, leading to low blood pressureand tissue ischemia that require emergentmedical treatment. If an arrhythmiacauses very rapid conduction of electricalcurrent to the myocardial cells, the heartmay not be able to sustain an organizedcontraction at all, and is calledfibrillation. While tachycardias andfibrillation can affect the atria or theventricles, ventricular tachycardia andfibrillation are life-threatening.In the case of atrial fibrillation, the atria

are unable to effectively pump blood intothe ventricles. However, the ventricles areable to fill to about 70% without anycontribution from atrial contraction. Ifthe AV node does not conduct the veryrapid rate of the atria to the ventriclesand the heart is not working very hard, anindividual may be able to tolerate atrialfibrillation without experiencingischemia. However, atrial fibrillation islinked to an increased risk of stroke fromclots formed in blood within the atriathat are not effectively contracting.Treatment of atrial fibrillation generallyincludes measures to control theventricular rate, medications whenindicated to decrease the risk of clottingand measures when possible to convertthe heart back into a normal rhythm andmaintain such a rhythm. In the case of ventricular tachycardia

and fibrillation, the ventricles are unableto effectively contract to pump blood,leading to rapid loss of consciousness anddeath. The treatment is to apply an

external electric shock to the heart toreset the normal rate rhythm, which istermed cardioversion. Individualsmeeting specific clinical criteria, such assevere heart failure or underlyingabnormal heart rhythms may be eligiblefor implantation of an automated internalcardiac defibrillator (AICD). The AICD isprogrammed to sense onset of apotentially fatal arrhythmia and deliveran electric shock to the myocardium. TheAICD has been associated with a decreasein mortality for those who meet theclinical eligibility criteria.

HEART BLOCK

Heart block occurs when theconduction of electrical current throughthe heart is delayed or completelyblocked. A complete interruption is calleda complete heart block or a third degreeheart block and frequently involvesdamaged cells in the AV node. Thirddegree heart block can be life-threatening.If the electrical current from the atriacannot be conducted through the AVnode into the Purkinje fibers, theventricles may not be able to contract at asufficient rate to maintain adequate bloodpressure to sustain life. In cases such as athird degree heart block, a cardiologistcan implant a pacemaker to deliverelectric shocks directly into themyocardium to cause a contraction atnormal heart rates.

CONCLUSION

CHD is the most common heartproblem that fire fighters will experience.The process of plaque deposition andgrowth is gradual and often can beprevented and treated effectively. Firefighters should be aware of the major riskfactors for CHD and the lifestyle andmedical measures that can help themdecrease their risk of developing CHD(see Chapter 5). n

14

i Kales SN, Soteriades ES, Christophi CA, et al.Emergency duties and deaths from heart diseaseamong firefighters in the United States. N Engl J Med.2007;356:1207–1215.

ii From The Merck Manual Home HealthHandbook, edited by Robert Porter. Copyright2010-2011 by Merck Sharp & Dohme Corp., asubsidiary of Merck & Co., Inc., Whitehouse Station,NJ. Available at:http://www.merckmanuals.com/home/index.html.Accessed (3/31/12).

iii From The Merck Manual Home HealthHandbook, edited by Robert Porter. Copyright

2010-2011 by Merck Sharp & Dohme Corp., asubsidiary of Merck & Co., Inc., Whitehouse Station,NJ. Available at:http://www.merckmanuals.com/home/index.html.Accessed (3/31/12).

iv Soteriades ES, Smith DL, Tsismenakis AJ, Baur,DM, Kales SN. Cardiovascular disease in USfirefighters. Cardiology in Review. 2011;19:202-215.

v Schoen, F.J.: Interventional and SurgicalCardiovascular Pathology, Clinical Correlations andBasic Principles. Philadelphia, W.B. Saunders Co.,1989, Figure 7, p. 59.

vi From The Merck Manual Home Health

Handbook, edited by Robert Porter. Copyright2010-2011 by Merck Sharp & Dohme Corp., asubsidiary of Merck & Co., Inc., Whitehouse Station,NJ. Available at:http://www.merckmanuals.com/home/index.html.Accessed (3/31/12).

vii Geibe JR, Holder J, Peeples L, et al. Predictors ofon-duty coronary events in male firefighters in theUnited States. Am J Cardiol. 2008;101:585–589.

viii Brusch JL, et al. (11/29/11). InfectiveEndocarditis. Retrieved fromhttp://emedicine.medscape.com/article/216650-overview

Sudden cardiac death is the leadingcause of on-duty deaths among firefighters.i The vast majority of these casesare due to coronary heart disease (CHD).ii

Research has identified multiple riskfactors in the general population fordeveloping CHD that are universallyaccepted. Additionally, fire fighters facespecial occupational exposures andhazards that may contribute to the risk ofCHD, and some of these exposures havebeen shown to increase the odds oftriggering acute cardiovascular events thatcan lead to premature retirement anddeath. Many of the standard CHD riskfactors for the general population werederived from large scale, prospectivecohort studies, such as the FraminghamHeart Study and Nurses’ Health Study.Some CHD risk factors, like diet andphysical activity, can be improved orworsened by changes in behavior, lifestyleand the work environment. Therefore,they are known as modifiable risk factors.Other risk factors, like age and gender,cannot be changed and are callednon-modifiable risk factors. This chapterreviews major CHD risk factors,categorizing them into standard riskfactors- modifiable and non-modifiable-and special occupational risk factors facedby fire fighters.

STANDARD CHD RISKS IN FIRE FIGHTERS

Studies of fire fighters who experienceon-duty CHD events and prematureretirements related to heart disease haveidentified several risk factors that areassociated with an increased probabilityor “odds ratio” of having an on-dutyCHD event. These are identical to manyof the key risk factors previouslyidentified during research of the generalpopulation. Fire fighters who developon-duty CHD events have an excess ofthese risk factors compared to firefighters who do not develop on-dutyCHD events. Table 5.1 summarizesresearch findings. For example, currentsmokers have over eight times greaterodds of experiencing on-duty CHDfatalities compared to those not currentlysmoking, as well as having over two times

greater odds of a non-CHDcardiovascular retirement and almostfour times greater odds of CHDretirements. Likewise, fire fighters withhypertension have twelve times greaterodds of experiencing on-duty CHDfatalities compared to those with normalblood pressure.

MODIFIABLE RISKS

Tobacco UseCigarette smoking resulted in an estimated

443,000 premature deaths each year from2000 to 2004 due to smoking-relatedillnesses, with approximately 49,000 of thesedeaths attributable to second hand smoke.iv

Tobacco has been associated with harmfulchanges in blood pressure, carbonmonoxide and lipid levels. Cigarettesmokers are 2 to 4 times more likely todevelop CHD compared to non-smokers.iv

On average, male smokers die 13.2 yearsearlier than male nonsmokers, and femalesmokers die 14.5 years earlier than femalenon-smokers.iv

Exposure to second hand tobacco smokehas been associated with increased CHDrisk. Non-smokers who are exposed tosecond hand smoke at home or workincrease their risk of developing CHD by25% to 30%.v Brief exposures to smoke(direct or second hand) can causeplatelets to become stickier, damage to thelining of blood vessels, and decreasecoronary flow reserves, potentiallyincreasing the risk of a heart attack.v

While some U.S. states have enactedlegislation that prohibits hiring firefighters who smoke, tobacco use continuesamong some fire fighters in communitieswithout smoking restrictions. Recentresearch estimates the prevalence ofsmoking in the fire service from 10 to18%.vi However, among fire fighters whohave died from on-duty CVD events, theprevalence ranges from 40-50%.vi

While smoking among fire fighters hasdeclined, it has unfortunately beenaccompanied by an apparent increase inthe use of smokeless tobacco. A recentlarge survey found that almost 1 in 5 or17-18% of fire fighters in the central U.S.use smokeless tobacco.vii Fire fightersshould know that although smokelesstobacco may be less harmful than smokingtobacco, nonetheless, its use has beenassociated with an increased risk of deathfrom heart attack and stroke and increasedrisk of cancers of the mouth and throat.viii,ix

High Blood PressureHigh blood pressure, or hypertension, is

defined by having any one of thefollowing conditions:

• systolic blood pressure > 140 mm Hg.

• diastolic blood pressure > 90 mm Hg.

• taking antihypertensive medicine.

• having been told at least twice by aphysician or other health professionalthat one has high blood pressure.

15

Heart Disease in the Fire ServicecHaPter 5 • risk factOrs fOr Heart disease

On-Duty CHD Non-CHD Cardiovascular CHD Retirements Fatalities OR (95% CI) Retirements OR (95% CI)

OR (95% CI)

Current smoking 8.6 (4.2-17) 2.5 (1.2-5.1) 3.9 (2.5-6.2)

Hypertension 12 (5.8-25) 11 (6.1-20) 5.4 (3.7-7.9)

Obesity (BMI >30 kg/m2) 3.1 (1.5-6.6) 3.6 (2.0-6.4) 1.4 (0.96-1.93)

Total Cholesterol > 200 mg/dL 4.4 (1.5-13) 1.1 (0.51-2.24) 2.4 (1.6-3.6)

Diabetes mellitus 10.2 (3.7-28) 7.7 (2.9-20) 13 (6.1-28)

Prior diagnosis of CHD 35 (9.5-128) NA 30 (9.1-96)

Age >45 years old 18 (8.5-40) 26 (13-51) 63 (35-111)

CHD, Coronary Heart Disease; OR, Odds Ratio; CI, Confidence Intervals; BMI, Body Mass Index

Table 5.1 iii

In the United States, one in three adultshas high blood pressure.x There are alsoethnic variations in the prevalence andseverity of hypertension, with theprevalence of hypertension amongAfrican-Americans being one of thehighest in the world. Generally, comparedto whites, blacks develop high bloodpressure earlier in life and their averageblood pressures are higher. As a result,compared to whites, blacks have a 1.5times greater rate of death caused byheart disease.xi Chronic, uncontrolledhypertension may lead to left ventricularhypertrophy (see Chapter 4), as the heartmust work harder to pump blood againstan increased pressure. Long-term effectsof hypertension include increased risk ofheart disease, stroke and kidney disease.Data from the Framingham Heart Studyindicate that hypertension is associatedwith shorter life expectancy, with total lifeexpectancy 5.1 years longer for menwithout hypertension and 4.9 yearslonger for women without hypertensionat 50 years of age.xii Figure 5.1 shows thatthe heart disease rate per 1,000 peopleincreases as the systolic and diastolicblood pressure levels increase; with menhaving higher rates of heart disease thanwomen. There is evidence that adverse events

attributed to hypertension may beconcentrated in those individuals withundiagnosed or inappropriately treatedhypertension. In fire fighters who hadautopsies after an on-duty death fromCHD, 56% had left ventricularhypertrophy and/or enlarged hearts,which is also known as cardiomegaly.xiv Ina prospective study of fire fighters withhypertension, almost 75% lackedappropriate treatment of their bloodpressures.xv Investigators in another studyobserved almost three times the rate ofadverse employment outcomes (includingon-duty death, on-duty injury, andpremature retirement) with hypertension,largely due to fire fighters with high bloodpressure who were not taking medicationto control their hypertension.xvi

Approximately 20% to 30% of fire fightershave hypertension.xvii

Although many health effects of chronichypertension have been described, newerresearch indicates that blood pressure inthe prehypertension range is also harmful.Prehypertension is defined as untreatedsystolic blood pressure of 120-139 mm Hgor untreated diastolic blood pressure of

80-89 mm Hg.xviii The presence ofprehypertension may also be a marker forother CHD risks. In a survey study of thegeneral population, people withprehypertension were more likely thanthose with normal blood pressure levels tohave above-normal cholesterol levels,diabetes mellitusxix, and beoverweight orobese. Compared to normal bloodpressure, prehypertension in theFramingham Heart Study was associatedwith a 1.5 to 2-fold risk for majorcardiovascular disease eventsxix. MostCHD events in the general population andamong emergency responders occur inpeople with prehypertensive to mildlyelevated blood pressures with averagesystolic pressure of 140 to 146 mm Hg anddiastolic pressures ranging between 88 to92 mm Hg.xx Approximately 50% of firefighters have blood pressures in theprehypertensive range.xx

ObesityObesity, defined as a Body Mass Index

(BMI) >30 kg/m2 or total body fat > 25%,is a well-established risk forcardiovascular disease. Some assume thatBMI falsely over-estimates the number ofobese individuals. While this can be trueamong athletes and others who have amuscular build, it may not be true forsome fire fighters. In a recentinvestigation of career and volunteer firefighters it was shown that obesity waseven more prevalent when measured withbody fat as compared to BMI.xxi Thestudy also found those that had highBMIs also had high cholesterol levels,higher blood pressure and a lowerexercise tolerance. Regardless of how it is measured, recent

scientific research suggests that thedistribution of body fat is an importantpredictor of negative health outcomes.

16

Figure 5.1 xiii

Individuals with moreintra-abdominal/visceral fat, which is fataround abdominal organs, are at anincreased risk of hypertension,dyslipidemia, coronary artery disease, andpremature death. Excessive abdominalfat, as revealed by waist circumferencemeasures, creates increased inflammationin the body. This occurs because fat cellsrelease pro-inflammatory cytokines, cellsignaling molecules that activate theimmune system, which ‘turns on’ aninflammatory cascade at genetic andcellular levels, ultimately affecting theentire body. This is important becausecurrent scientific research linkschronically increased inflammation toseveral chronic disease states such ascardiovascular disease,prediabetes/diabetes, cancer, anddementia. Expert consensus indicates thata waist circumference measurement,measured at the level of the iliac crests(the curved ridge at the top of the hipbone) that is greater than 102 cm (40inches) in men, and 88 cm (35 inches) inwomen imparts a significant increase inthe risk of chronic disease, includingcardiovascular disease. Elevated BMI is a predictor for diabetes

mellitus, stroke, sleep-disorderedbreathing, as well as other healthconditions, including some cancers, liverdisease, gallbladder disease,musculoskeletal diseases and reproductiveabnormalities. In analysis of data fromalmost 900,000 adults, overall mortalitywas lowest at BMI range of 22.5 kg/m2 to25 kg/m2, and each 5 kg/m2 higher BMIwas associated with approximately 30%higher all-cause mortality.xxii Data from

the Framingham Heart Study estimatethat the decrease in life expectancy due tobeing overweight, defined as a BMIbetween 25 kg/m2 to 30 kg/m2, rangesfrom a loss of 3.1 years for 40-year oldmale non-smokers to 6.7 years for malesmokers, and 3.3 years for 40-year oldfemale non-smokers to 7.2 years forfemale smokers.xxiii

In fire fighters, obesity is a risk factor forjob-related disability, on-duty coronaryheart disease events, and CHDretirements.xxiv Similar to the generalpopulation, the average BMI among firefighters and emergency responders isincreasing. Data collected in the 1980s andearly 1990s showed the average veteran firefighter had a BMI that ranged from 25.4kg/m2 to 26.7 kg/m2, but by 1996-1997 themean BMI was 29 kg/m2 and by 2001 ithad increased to 29.7 kg/m2.

Cholesterol and TriglyceridesCholesterol and triglycerides are types of

molecules referred to as lipids.Cholesterol is required for essential bodilyfunction, such as cell wall and hormonesynthesis. Cholesterol is transportedthroughout the body bound to carrierproteins, including low densitylipoprotein (LDL) and high densitylipoprotein (HDL). LDL is responsible fordelivery of cholesterol to body tissue andis commonly referred to as “badcholesterol.” HDL transports cholesterolaway from body tissues and is often called“good cholesterol.” Triglyceridescomprise the fat stored in our bodies.Elevated concentrations of totalcholesterol, LDL cholesterol, triglyceridesand decreased levels of HDL have been

associated with increased risk of CHD.Figure 5.2 illustrates the association ofheart disease mortality with increasinglevels of total cholesterol. Fire fighters may not always have the

opportunity to eat meals at a regular timedue to the demands of being available torespond to emergencies. Like other shiftworkers, fire fighters are more likely to eatmeals with higher proportion of fats thatadversely affect blood lipid levels.xxvi

Among fire fighters, the prevalence of lowHDL (<40 mg/dL) ranges from 26% to31%, and high fasting triglycerideconcentrations (>150 mg/dL) have beenfound in over 20%.xxvii, xxviii These valuesare comparable to surveys of the generalpopulation, which demonstrate thatamong adult males the prevalence of lowHDL is 28.6% and that approximately 1in 3 U.S. adults had a triglyceride level>150 mg/dL during 1999-2004.xxix

Similar to the general population, adversehealth effects from abnormal blood lipidlevels, or dyslipidemia, are observed infire fighters, although precise assessmentof dyslipidemia as an independent riskfactor for on-duty CHD events have beenlimited by studies lacking premorbid lipidvalues in fire fighters who suffer events.However, in unadjusted analyses, hightotal cholesterol (>200 mg/dL) isassociated with a 2.4-fold increased riskof coronary heart disease retirement and4.4-fold increased risk of on-dutycoronary heart disease death.xxx, xxxi

Diabetes MellitusDiabetes mellitus is a disease of blood

sugar or glucose metabolism due todeficiencies (Type I) or resistance to(Type II) insulin, a hormone. Individualswith diabetes have elevated glucoseconcentrations and often have concurrenthypertension and lipid disorders.Diabetes conveys an increased risk forboth coronary heart disease and fatalheart attacks. The prevalence of Type IIdiabetes in the fire service has beenobserved to range from 1% to 4% .xxxii, xxxiii,xxxiv Among fire fighters, diabetesaccounts for about 21% of on-duty CHDevents and 26% of CHD-relatedretirements.xxxv, xxxvi Type II diabetes aloneis not a significant predictor of on-dutyCHD and CHD retirements. xxxv, xxxvi Thisis likely because diabetes modifies the riskof CHD through its effects onhypertension, cholesterol levels, andatherosclerosis.

17

Figure 5.2 xxv

Established CHD and CHD EquivalentsEstablished CHD is disease that is

already present, and conditions defined asCHD equivalents, such as peripheralartery disease, carotid stenosis, stroke ortransient ischemic attacks, are consideredtogether for risk assessment purposes.CHD or a CHD equivalent is associatedwith a very high risk of subsequentfurther on-duty CHD events, on-dutyCHD fatality and CHD retirements. Theprevalence of established CHD is as lowas 1% in career fire fighters, but as high as9% in volunteers.xxxvii, xxxviii For comparison,the prevalence of established CHD in USadult males is 8.3%.xxxix In studies of firefighters, previously diagnosed CHDaccounted for 31% of fatal on-duty CHDevents and 18% of nonfatal on-duty CHDevents.xl This translates to a greater than30-fold risk of on-duty CHD events forthose fire fighters with a pre-existingCHD diagnosis.

Metabolic SyndromeMetabolic syndrome refers to a cluster

of risk factors for cardiovascular diseaseand Type II diabetes mellitus. It is anindependent predictor for cardiovascularevents and has also been associated withatrial fibrillation and heart failure. Themost recent criteria defines metabolicsyndrome when >3 of the following riskfactors are present xli:

• fasting plasma glucose >100 mg/dL or

undergoing treatment for elevatedglucose.

• HDL cholesterol <40 mg/dL in men or< 50 mg/dL in women or undergoingdrug treatment for reduced HDL.

• fasting triglycerides >150 mg/dL orundergoing drug treatments forelevated triglycerides.

• abdominal obesity (elevated waistcircumference, population- andcountry specific) for U.S. men waistcircumference ≥ 94 cm.

• blood pressure >130 mm Hg systolicor >85 mm Hg diastolic or undergoingdrug treatment for hypertension orantihypertensive drug treatment in apatient with a history of hypertension.

The prevalence of metabolic syndromevaries by the definition used in earlierstudies. The age-adjusted prevalence was35.1% for men and 32.6% for womenaccording to NHANES 2003 to 2006 data,and among men, the age-specificprevalence was 20.3% for those 20 to 39years of age, 40.8% for men 40 to 59 yearsof age and 51.5% for men >60 years ofage.xlii In an analysis of multiple studies,metabolic syndrome was associated witha 1.54-fold increase in relative risk forcardiovascular events after adjustment forthe individual components of the

syndrome.xliii The observed cardiovascularrisk associated with the metabolicsyndrome increases with the number ofcomponents and varies with the possiblecombination of components. The greatestrisk was observed with the combinationof central obesity, high blood pressureand hyperglycemia.xliv

A recent study of U.S. career fire fightersfrom the Midwest found an alarminglyhigh prevalence (28.3%) of metabolicsyndrome among these emergencyresponders expected to be younger, moreactive and healthier than the general U.S.adult population. xlv As expected theprevalence of metabolic syndromeincreased with the age of these firefighters: 15% in the youngest (18-29years) to 35% oldest (50-62 years). In thisstudy, fitness level was measured by anindividual performing an exercise test anda metabolic equivalent of task (MET) wascalculated. A MET is defined as the rate ofoxygen consumption during a taskcompared to a resting rate and can beconsidered as an index of the intensity ofan activity. A MET value of 1 correlates toquiet sitting, 11.8 METS correlates torunning at 8 miles per hour or at a paceof 7.5 minutes a mile xlvi.As seen in Figure 5.3, fire fighters with

the same fitness levels, as defined bynumber of METS calculated from theexercise test, had roughly the sameprevalence of metabolic syndrome, evenamong different age groups. However, asfitness levels decrease, the prevalence ofmetabolic syndrome increasesdramatically among fire fighters of thesame age group. After controlling forphysical fitness, as measured by theexercise test, age was no longer asignificant predictor of the metabolicsyndrome.

Physical Activity/ Physical FitnessMany epidemiologic studies in the

general population have proven thatincreasing physical activity and physicalfitness significantly lowers the risk ofCHD.xlvii, xlviii The mechanisms ofdecreased risk are multifactorial andinclude improved body composition andreduced levels of cardiovascular riskfactors and inflammation. Physicalactivity is defined as self-reportedphysical exertion such as exercise; whereasphysical fitness is defined by objectivemeasurements such as treadmill exercisetolerance tests. Because measured fitness

18

Figure 5.3 xlv

is a more accurate measure thanself-reported activity, increases incardiorespiratory fitness are associatedwith greater decreases in CHD risk.xlviii

For example, in a large meta-analysis eachone MET increase in fitness conveyed13% and 15% decrements in all-causemortality and CHD, respectively.xlvii

Many fire departments do not requireregular exercise regimens or themaintenance of discrete physical fitnessparameters after hire.xlix Fire fightersexperience prolonged sedentary periodspunctuated by having to perform verystrenuous tasks, and may not have theopportunity to engage in regular physicalactivity of adequate intensity andduration. This is especially important as itrelates to on-duty CHD events, as studieshave demonstrated that heavy physicalexertion can trigger the onset of a heartattack, particularly in those who do notengage in regular exercise of adequateduration and intensity. On the positiveside, recent studies in fire fighters havedemonstrated that increasing levels ofphysical activity and especially physicalfitness are associated with improvedcardiovascular risk profiles and a lowerrisk of metabolic syndrome (see above).l, li

Poor Dietary HabitsIn randomized controlled trials, dietary

habits affect multiple cardiovascular riskfactors, such as blood pressure, LDL andHDL cholesterol, triglycerides, glucoselevels and obesity.v While multipleprospective cohort trials indicate littleeffect of total fat consumption oncardiovascular disease risk, each 2% ofcalories from trans fat was associated witha 23% higher risk of CHD.lii, liii Regardingcarbohydrate consumption, pooledanalysis from 11 cohort studies observedthat for each 5% energy of carbohydrateconsumption in place of saturated fat wasassociated with a 7% increase in risk ofCHD.liv Similarly, results from the Nurses’Health Study noted that regularconsumption of sugar-sweetenedbeverages was independently associatedwith a higher incidence of CHD.lv In theU.S. general population, it is estimatedthat on an annual basis, high dietary saltintake is responsible for 102,000 deaths,low dietary omega-3 fatty acids for 84,000deaths, high dietary trans fat for 82,000deaths and low consumption of fruits andvegetables for 55,000 deaths.lvi

Fire fighters and emergency respondersare shift workers who are required torespond to unpredictable emergencies,resulting in unreliable meal times.“Firehouse culture” has a reputation forrecipes high in fat and dense in simple,refined carbohydrates, such as white riceor pasta made from white flour.lvii Despitegeneral awareness of some of the healthbenefits from healthy food choices,dietary habits do not always change. Forexample, in one study of fire fighters withan 84% prevalence of overweight orobesity, while 90% of study participantswere aware that food choices can preventthe development of heart disease, 37%reported that they enjoyed what they ateand did not want to change.lviii

NON-MODIFIABLE RISKS

Age/GenderAge is an independent predictor for

adverse CHD outcomes. Heart diseaseoccurs as people age, with youngerwomen at decreased risk of mortalityfrom CHD. With increased age, thedifference in CHD mortality betweenmen and women decreases. The observeddifference has been explained by theeffects of female hormones, calledestrogens, which offer a protective benefitto premenopausal women; however,women have a lower survival rate after aheart attack at all ages compared to men.Figure 5.4 depicts age specific CHDmortality for men compared to women.As expected, similar relationships have

been observed in fire fighters, with therisk of on-duty CHD deaths increasing

dramatically after the age of 40, which isdepicted in Figure 5.5.

Family HistoryPremature paternal history of a heart

attack approximately doubles the risk of aheart attack in men and increases the riskin women by about 70%.lxi, lxii Similarly,history of heart disease in a siblingincreases the odds of heart disease in menand women by approximately 50%.lxiii

The increased risk of heart diseaseassociated with family history ispresumably related in part to commongenetics. However, the full genetic basisfor CHD has not yet been determined,and the genetic markers identified to datehave not been shown to add significantlyto existing CHD risk prediction tools.lxiv

OCCUPATIONAL CHD RISKS IN FIRE FIGHTERS

Fire fighters face hazardous exposuresand exceptional working conditions thatmay increase their risk of CHD. These canbe divided into acute and chronicstressors, as depicted in Table 5.2.

Smoke ExposureInhalation of smoke containing gases

and particulates is a hazard to firefighters. While use of self-containedbreathing apparatus (SCBA) during fireattack and suppression may decreaseexposure, fire fighters may not wearSCBA or other respirators during the“overhaul” period after a fire, eventhough harmful inhalants have beendocumented to be present.lxv, lxvi Fire

19

Figure 5.4 lix

fighters should be encouraged to wearappropriate personal protectiveequipment during all activities withsmoke exposure.lxvii

Smoke containing chemical asphyxiants,such as carbon monoxide, cyanide andhydrogen sulfide, interferes with effectiveoxygenation and can lead to myocardialischemia in people with CHD. Manyeffects of exposure to carbon monoxidehave been described. Carbon monoxide isformed by the incomplete combustion ofcarbon, and binds to hemoglobin, theprotein in red blood cells that carryoxygen to the body. At sufficientconcentrations, carbon monoxide cancause reduced exercise capacity and leadto myocardial ischemia, even in anotherwise healthy heart.lxviii In animalstudies, chronic exposure to carbonmonoxide has been associated withaccelerated atherosclerosis.lxix Otherchemicals that may be found in productsof combustion include particulates, whichhave been associated with autonomicdysfunction, including arrhythmias,increased heart rate and decreased heartrate variability.lxx, lxxi, lxxii Additionalsubstances with suspected or knowndirect and indirect cardiac effects thatmay be present in combustion productsinclude polycyclic aromatichydrocarbons, arsenic, carbon disulfide,lead and cadmium.lxxiii While plausiblemechanisms for increased CHD risk fromsmoke exist, additional research will

further quantify the cardiovascularconsequences of chronic smoke exposureamong fire fighters.

NoiseExposure to noise has been linked with

increased blood pressure. Alarms, vehicleengines and mechanized rescueequipment typically generate noiseexposures between 63 to 85 decibels(dBA).lxxiv However, documentedexposures have been as high as 116dBA.lxxv It is estimated that systolic bloodpressure acutely rises by 0.51 mm Hg foreach 5 decibel increase in acuteoccupational noise exposure.lxxvi Whilethere is general agreement that bloodpressure response to intermittent noise

will persist during the exposure, there isnot currently sufficient evidence todetermine if this effect islong-standing.lxxvii

Psychological StressFire fighters experience increased and

various psychological stressors at work.Work related factors that appear tocontribute to increased stress include highoccupational demands and low decisionallatitude, presumably leading to changes inthe nervous system and hormonalhomeostasis with subsequent elevatedblood pressure, elevated heart rate,dyslipidemia and poor sleep.lxxviii

Susceptible fire fighters who are exposedto extreme stressors may developpost-traumatic stress disorder, which isalso associated with adverse effects onblood pressure, heart rate and themetabolic syndrome.lxxix, lxxx, lxxxi

Shift WorkFire fighters work long shifts and may be

required to staff rotating shifts. Thepresence of overtime and second jobsmay also contribute to chronic sleepdeprivation. Evidence from otheroccupations supports the associationbetween shift work and increased risk ofcardiovascular disease.lxxxii Themechanisms are likely multifactorial,involving altered diet, sleep disruption,physical inactivity, psychological stressand altered circadian rhythms.lxxxiii, lxxxiv

Sleep deprivation has been associatedwith adverse metabolic changes,hypertension and cardiovasculardisease.lxxxv, lxxxvi, lxxxvii, lxxxviii

20

Figure 5.5 lx

Table 5.2 lxvii

Potential Occupational Cardiovascular Hazards

Chronic Acute

Long sedentary periods Irregular physical exertion

Smoke exposure Smoke exposure

Noise Noise

Shift work/partial sleep deprivation Excess heat/dehydration

Fire house dietary patterns Duty-specific hazards

Occupational stress Firefighting activities

Post-traumatic stress disorders Physical training

High job demand and low decisional control Alarm response

ACUTE CARDIOVASCULAR STRAINOF FIREFIGHTING

Firefighting acts as a stressor on thecardiovascular system in several ways. Anindividual’s physiologic response largelydepends on underlying health status andcardiorespiratory fitness, as depicted inFigure 5.7.

Sympathetic ActivationFirefighting induces activation of the

sympathetic nervous system withassociated release of catecholamines likeepinephrine (adrenaline). This “fight orflight” response can cause rapid increasein heart rates. In studies that recordedheart rates of fire fighters responding toalarms, investigators noted heart ratesrose quickly in response to the stationalarm, and reached maximal ornear-maximal rates during simulated oractual fire emergencies.lxxxix, xc, xci, xcii, xciii, xciv

For example, even though the physicalactivity required to enter a truck afterhearing an alarm should not increase theheart rate to more than 100 beats perminute, heart rates, especially amongyounger fire fighters, increased to as highas 130-150 beats per minute after analarm sounded.xciv

Physical WorkloadFirefighting requires strenuous exertion,

such as carrying tools and wearingpersonal protective equipment, advancinghose lines, breaching walls, ceilings androofs, climbing and performing rescues. Physical workload is measured using

metabolic equivalents, or METs. A METis defined as the rate of oxygenconsumption during a task compared to aresting rate and can be considered as anindex of the intensity of an activity. AMET value of 1 correlates to quiet sitting,11.8 METS correlates to running at 8miles per hour or at a pace of 7.5 minutesa mile.xcv Commonly, the number ofMETS is measured by an individualundergoing an exercise treadmill test. In a study of fire fighters performing

simulated firefighting duties, the timerequired to complete the tasks wasinversely correlated with the number ofMETS achieved on fitness testing.xcvi Inother words, fire fighters who had higherlevels of aerobic fitness as measured bytheir ability to reach a higher MET value,safely completed the tasks more quickly.Researchers who measured fitness levels

in a sample of fire fighters participating ina standard firefighting physical activitiestest noted that 100% of those who wereunable to reach 9.7 METS failed thetest.xcvii Numerous scientific studies havedemonstrated that the aerobic capacityrequired to perform firefighting tasksduring simulated fire conditions is at least12 METS (42 ml oxygen/kg/min). Atlevels below 12 METS, a fire fighter shallbe counseled to improve his or her fitnessand a prescribed aerobic program may bea consideration. At levels at or below 8METS, a prescribed aerobic fitnessprogram shall be required and theauthorities having jurisdiction (AHJ)shall be advised to consider restrictionfrom essential fire fighting job tasks.Ongoing studies are attempting toquantify fitness levels on the basis ofrelative risk of future health outcomes.xcviii

HeatFire fighters experience thermal strain

from the heat of fires as well as the heatgenerated by metabolic activities whileperforming tasks, which acts as acardiovascular stressor. Additionally,insulated personal protective equipmentlimits heat dissipation.xcviii Data gatheredfrom fire training estimate that core bodytemperatures increase at a rate of about0.05°C/min or 1.0°C after 20 minutes ofacute fire fighting.xcix, c, ci Susceptibleindividuals who experienced the samerate of temperature increase for longerperiods could suffer heat-related injuriesand illness. There are multiple recognized

factors that increase the risk of heatillness, including obesity, low levels ofphysical fitness, lack of acclimatization,dehydration and a prior episode of heatillness.xcviii, cii Certain medical conditions,including diabetes, heart disease,diarrhea, sunburn and viral illnesses; andmedications that interfere withthermoregulation, such as stimulants,anticholinergics and some cardiovasculardrugs are associated with an increasedrisk of heat illness.cii, ciii

DehydrationDehydration decreases plasma volume,

resulting in an increase in theconcentration of red blood cells, alsoknown as hemocentration, and impairedthermoregulation which may lead todecreases in cardiac output. Fire fightersmay secrete up to 1.2 to 1.9 L/hour of sweatduring strenuous firefighting while wearingpersonal protective equipment.civ, cv, cvi In astudy of fire fighters who completed aseries of three, 7-minute training drillswith live fires, stroke volume , or thevolume of blood that is pumped from oneventricle of the heart with each beat,decreased to almost 20% below baselinelevels, even though there was a 10-minutebreak to rest and drink fluids.civ

Dehydration linked hemoconcentrationmay be responsible for the increase incirculating platelets observed during firefighting and may lead to an environmentthat favors the formation of bloodclots.cvii, cviii

21

Figure 5.7 lxxxix

CONCLUSION

There are many known CHD riskfactors; some are modifiable, while others,such as age and gender are not. Both firefighters and the general population sharemany of the same risk factors.

Additionally, fire fighters also face specialoccupational circumstances that raise therisk of CHD and the risk for triggeringon-duty CHD events. Fire fighters canimprove their health by changingpersonal and professional modifiableCHD risk factors. Specifically, it is

important for fire fighters to have gooddiets, increase their physical fitnessthrough adequate exercise and physicalactivity and maintain good sleep hygieneby obtaining an average of 7-8 hours ofsleep per night. n

22

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lxxxvii. Di Lorenzo L, De Pergola G, Zocchetti C, et al.Effect of shift work on body mass index: resultsof a study performed in 319 glucose-tolerantmen working in a Southern Italian industry.Int J Obes Relat Metab Disord.2003;27:1353–1358.

lxxxviii. Kitamura T, Onishi K, Dohi K, et al. Circadianrhythm of blood pressure is transformed froma dipper to a non-dipper pattern in shiftworkers with hypertension. J Hum Hypertens.2002;16:193–197.

lxxxix. Soteriades ES, Smith DL, Tsismenakis AJ, BaurDM, Kales SN. Cardiovascular disease in US

firefighters: a systematic review. Cardiology inReview. 2011;19 (4):202-215.

xc. Barnard RJ, Gardner GW, Diaco NV.“Ischemic” Heart Disease in Firefighters withNormal Coronary Arteries. JOM 1976;18:818-820.

xci. Puttonen S, Harma M, Hublin C. Shift workand cardiovascular disease -pathways fromcircadian stress to morbidity. Scand J WorkEnviron Health. 2010;36:96–108.

xcii. Manning JE, Griggs TR. Heart rates in firefighters using light and heavy breathingequipment: similar near-maximal exertion inresponse to multiple work load conditions. JOccup Med. 1983;25:215–218.

xciii. Sothmann MS, Saupe K, Jasenof D, et al. Heartrate response of firefighters to actualemergencies. Implications for cardiorespiratoryfitness. J Occup Med. 1992;34:797– 800.

xciv. Kuorinka I, Korhonen O. Firefighters’ Reactionto Alarm, An ECG and Heart Rate Study. JOM1981; 23:762-766.

xcv. Ainsworth BE, Haskell WL, et al. 2011Compendium of physical activities: a secondupdate of codes and MET values. Medicineand Science in Sports and Exercise,2011;43(8):1575-1581.

xcvi. Elsner KL, Kolkhorst FW. Metabolic demandsof simulated firefighting tasks. Ergonomics.2008;51:1418 –1425.

xcvii. Hurley B. Physical Attributes of FirefighterPerformance. Paper presented at: ResearchPresentation to DHS, R&D, PI Meeting;2008;Washington, DC.

xcviii. Soteriades ES, Smith DL, Tsismenakis AJ, BaurDM, Kales SN. Cardiovascular disease in USfirefighters: a systematic review. Cardiology inReview. 2011;19 (4):202-215.

xcix. Smith DL, Petruzzello SJ. Selected physiologicaland psychological responses to live-fire drills indifferent configurations of firefighting gear.Ergonomics. 1998;41:1141–1154.

c. Smith DL, Petruzzello SJ, Chludzinski MA, etal. Selected hormonal and immunologicalresponses to strenuous live-fire firefightingdrills. Ergonomics. 2005;48:55–65.

ci. Carter JM, Rayson MP, Wilkinson DM, et al.Strategies to combat heat strain during andafter firefighting. J Thermal Biol. 2007:109–116.

cii. Cheung S. Heat Stress. In: AdvancedEnvironmental Exercise Physiology. ci.Champaign, IL; Human Kinetics; 2010:27– 48.

ciii. Delaney K, Goldfrank L. Thermal extremes inthe work environment. In: Rom WN, ed.Environmental and Occupational Medicine.4th ed. Philadelphia, PA: WoltersKluwer/Lippincott Williams & Wilkins;2007:1337–1350.

civ. Smith DL, Manning TS, Petruzzello SJ. Effectof strenuous live-fire drills on cardiovascularand psychological responses of recruitfirefighters. Ergonomics. 2001;44:244–254.

cv. Smith DL, Petruzzello SJ. Selected physiologicaland psychological responses to live-fire drills indifferent configurations of firefighting gear.Ergonomics. 1998;41:1141–1154.

cvi. Selkirk GA, McLellan TM, Wong J. Activeversus passive cooling during work in warmenvironments while wearing firefightingprotective clothing. J Occup Environ Hyg.2004;1:521–531.

cvii. Smith DL, Goldstein E, Petruzzello SJ.Firefighter Fatalities and Injuries: The Role ofHeat Stress and PPE. Urban-Champaign, IL:University of Illinois Firefighter Life SafetyResearch Center; 2008.

cviii. Smith DL, Petruzello SJ, Goldstein E, et al.Effect of life-fire training on firefighters plateletnumber and function. Prehosp Emerg Care.2011;15(2):233-9.

23

Cardiovascular disease is the leadingcause of on-duty death among firefighters. Research studies have identifiedmultiple cardiovascular risk factors thatfire fighters face. Chapter 5 discussedpotential occupational cardiovascularhazards in fire fighters (See Table 6.1) andnon-occupational risk factors. There is apreponderance of scientific evidencedemonstrating that efforts to decreasemodifiable factors can decrease the risk ofheart disease. This chapter will discusshow lifestyle changes can help prevent ordecrease the development ofcardiovascular disease.

PHYSICAL ACTIVITY

Fire fighters must have a high level ofphysical fitness to perform their jobduties. While any exercise is preferable toinactivity, regular aerobic activity andmuscle strengthening exercises arenecessary for primary and secondaryprevention of heart disease. Benefits ofregular exercise include positive changesin body weight, blood pressure,cholesterol, glucose, mood andcardiovascular fitness. There are several methods to define

intensity of exercise. The AmericanCollege of Sports Medicine (ACSM)defines exercise intensity by percentage ofmaximum heart rate (MHR), rate ofperceived exertion, and METS.i Moderateactivity has been defined as 64% to76%MHR, vigorous activity as 77% to 95%MHR. The MHR can be calculated bysubtracting your age from 220. Forexample, a 40 year old has a MHR of 180,and for moderate activity the target heartrate is 115 to 137 heart beats a minute.METS refers to metabolic equivalents andis determined by measuring the amountof oxygen consumed (see Chapter 5). TheACSM rates exercise intensity usingMETS. For men (for women, mean valuesare one to two METS lower than formen), shown in Table 6.1.

Some examples of physical activities inMETS areii :

For the general adult population, theUSDA recommendations for physicalactivity are:iii

• Muscle-strengthening activities thatinvolve all major muscle groups on 2or more days a week.

• At least 150 minutes (2 hours and 30minutes) a week of moderate-intensity,or 75 minutes (1 hour and 15 minutes) a week of vigorous-intensityaerobic physical activity, or anequivalent combination of moderate- and vigorous-intensity aerobic activity.Aerobic activity should be performedin episodes of at least 10 minutes, andpreferably, it should be spreadthroughout the week.

• For additional and more extensivehealth benefits, adults should increasetheir aerobic physical activity to 300minutes (5 hours) a week ofmoderate-intensity, or 150 minutes aweek of vigorous-intensity aerobic physical activity, or an equivalentcombination of moderate- andvigorous-intensity activity.

To reach your goal fitness level, anyexercise regimen will vary depending onindividual factors. It is recommended thatbefore starting an exercise program, youshould consult a physician if:

• You are over 40 years old and are notregularly physically active

• You have a chronic illness or requiredaily medications

• You develop concerning symptomswith exertion that include but are notlimited to chest pain, difficultybreathing, or dizziness.

WELLNESS AT WORK

Fitness and wellness programs, ifproperly designed and administered, offeran opportunity for prevention ofcardiovascular disease. A comprehensiveprogram should emphasize healthy diets,regular physical activity and good sleephygiene, as well as provide continuingeducation and Employee AssistancePrograms (EAP) options.iv

The Fire Service Joint LaborManagement Wellness-Fitness Initiative(WFI) is a historic partnership betweenthe IAFF and the InternationalAssociation of Fire Chiefs (IAFC) as a wayto improve the wellness of firedepartment uniformed personnel. Tenpublic career fire departments from theUnited States and Canada participated.Each of these departments committedthemselves to this Wellness-FitnessInitiative by requiring mandatoryparticipation of all of their uniformedpersonnel in this program.

24

Heart Disease in the Fire ServicecHaPter 6 • Preventing Heart disease

AGE (years) # METS (moderate) # METS (vigorous)

20-39 4.8 - 7.1 7.2 - 10.1

40-64 4.0 - 5.9 6.0 - 8.4

65-70 3.2 - 4.7 4.8 - 6.7

Table 6.1 i

• Running, 4 mph (13 min/mile) 6 METS

• Walking, carrying 25 to 49 lb load, upstairs 8 METS

• Bicycling, 14-15.9 mph 10 METS

• Walking, carrying > 74 lb load, upstairs 12 METS

• Running, 9 mph (6.5 min/mile) 12.8 METS

The intention of the WFI is that itsimplementation should be a positiveindividualized program that isnon-punitive. All component results aremeasured against the individual’sprevious examinations and assessmentsand not against any standard or norm.However, medical practice standards maybe used when results indicate thatlifesaving intervention is required. Confidentiality of medical information is

the most critical aspect of the WFI. Theunauthorized release of personal detailswhich may be recorded as part of a medicalevaluation causes legal, ethical, andpersonal problems for the employee,employer and examining physician. Allinformation obtained from medical andphysical evaluations should be consideredconfidential, and the employer will onlyhave access to information regarding fitnessfor duty, necessary work restrictions, and ifneeded, appropriate accommodations.Also, all medical information must bemaintained in separate files from all otherpersonnel information.The WFI is a comprehensive program

that addresses the needs of the totalindividual in a program to build andmaintain fit fire fighters and EMSpersonnel. Fitness—physical, mental, andemotional— requires an effective wellnessprogram available to recruits, incumbents,and retirees. Components of the WFIinclude medical evaluation, fitness, injury/fitness/medical rehabilitation, behavioralhealth, and data collection.The WFI is designed to improve the

quality of life for all fire fighters whilesimultaneously seeking to prove the valueof investing wellness resources over time.The Cost Justification Chapter of the WFIThird Edition outlines the significant costsavings in lost work time, workerscompensation, and disability whenimplementing a comprehensivewellness-fitness program.

HIGH BLOOD PRESSURE

High blood pressure or hypertension is arecognized risk factor for heart disease.Untreated, elevated blood pressure canalso damage the brain, kidneys and eyes.While family history and genetics maycontribute to the incidence of high bloodpressure, the impact of lifestyle choicescannot be underemphasized. Adoption ofhealthy lifestyles is critical for theprevention of hypertension, essential for

the management of those with high bloodpressure, and has been shown to decreasecardiovascular risk.v

Major lifestyle changes that have beenshown to lower blood pressure includeweight loss in those who are overweightor obese; adoption of the DietaryApproaches to Stop Hypertension(DASH) eating plan; regular physicalactivity; moderation of alcohol andsodium consumption.vi Healthy behaviorsalso enhance the efficacy ofantihypertensive medications used totreat those with high blood pressures. Forexample, adoption of the DASH eatingplan has effects similar to a single drugtherapy, while combination of severallifestyle modifications can achieve evenbetter results.vii Adjunctive to behaviorchange, pharmacologic treatments havebeen shown to reduce the complicationsof hypertension. Clinical trials havedemonstrated that goal blood pressurelevels can be achieved in most patientswho are hypertensive, with many provenmedications to choose from.

PSYCHOLOGICAL STRESS

Fire fighters face many psychologicalstressors while performing duties thatinclude responding to fires, performingrescues, terrorism, etc. Excessive stressmay lead to increased heart rate, elevatedblood pressure and sleep disturbances.viii

Personal and occupational stressors canalso contribute to unhealthy behaviors

such as smoking, excessive eating, orincreased alcohol consumption.Susceptible fire fighters exposed toextreme stressors may developpost-traumatic stress disorder (PTSD). Although working conditions have a

primary role in causing job stress,individual and other situational factors canstrengthen or weaken this influence.ix Forexample, a sick family member or need towork a second job may intensify the effectsof work stressors. However, individualfactors can also help to reduce the effectsof occupational stressors, such as a balancebetween work and family or personal life, asupport network of friends and coworkers,and a relaxed and positive outlook.ix

There are many signs and symptoms ofdifficulty coping with stress. Learning torecognize when you or a coworker is havingdifficulty coping with stress is important socorrective action can be taken. Knowinghow and when to ask for assistance canavert negative consequences of stressors.Many departments have employeeassistance programs (EAPs) that provideconfidential, short term counseling. Because there are many causes of work

stressors, there are many strategies to reduceor prevent them. While it may not bepossible to immediately address the sourceof the stress, there are preventive steps thatcan be taken. The American PsychologicalAssociation suggests the following tipsx:

Identify the cause. You may find that yourstress arises from something that’s easy tocorrect. A psychologist can help you defineand analyze these stressors, and developaction plans for dealing with them.

Monitor your moods. If you feel stressedduring the day, write down what caused italong your thoughts and moods. Again,you may find the cause to be less seriousthan you first thought.

Make time for yourself at least two or threetimes a week. Even ten minutes a day of“personal time” can help refresh yourmental outlook and slow down your body’sstress response systems. Turn off the phone,spend time alone in your room, exercise, ormeditate to your favorite music.

Walk away when you’re angry. Before youreact, take time to mentally regroup bycounting to 10. Then look at the situationagain. Walking or other physical activitieswill also help you work off steam.

25

STEPS YOU CAN TAKE TODAY

• Aerobic and muscle strengtheningexercises that includes moderatephysical exertion for at least 30minutes on most days of the week.

• Maintain a healthy weight.

• Eat a healthy diet that limits sodiumto <1.5 grams a day.

• Don’t smoke.

• Limit daily alcohol use to < 2 drinksfor men and < 1 drink for women.

• Check your blood pressureperiodically as hypertension may nothave any symptoms.

• Treat high blood pressure if you havehypertension.

Analyze your schedule. Assess yourpriorities and delegate whatever tasks youcan (e.g., order out dinner after a busyday, share household responsibilities).Eliminate tasks that are “shoulds” but not“musts.”

Set reasonable standards for yourself andothers. Don’t expect perfection.

OBESITY

Overweight and obesity are terms forranges of weight that are greater thanwhat is generally considered healthy for agiven height.xi Being overweight or obeseis associated with increased risk of futureadverse health effects. There is a nationalobesity epidemic, with over two out ofevery three adults in the U.S. currentlyoverweight or obese.xii Analysis of datatrends from the Framingham Heart Studyrevealed that among normal weightadults between 30 and 59 years of age, thefour year rates of becoming overweightvaried from 26% to 30% in men and 14%to 19% in women.xiii

Among adults, overweight and obesityranges are commonly determined usingweight and height to calculate a bodymass index (BMI). BMI is used becausefor most people, it correlates with theamount of body fat. An adult with a BMIbetween 25 kg/m2 and 29.9 kg/m2 isconsidered overweight, while an adultwith a BMI of >30 kg/m2 is consideredobese. As an example, an adult who is5’9”tall and weighs 169 lbs. to 202 lbs. hasa BMI that is overweight, while an adultwho is 5’9” tall and weighs 203 lbs. ormore has a BMI that is obese. Eventhough BMI correlates with the amountof body fat, BMI does not directlymeasure body fat. Other methods ofestimating body fat and body fatdistribution include measurements ofskinfold thickness, waist circumference,calculation of waist-to-hip circumferenceratios, and other techniques such asultrasound, bioelectrical impedance,computed tomography, magneticresonance imaging and dual-emissionX-ray absorptiometry (DEXA or DXA). An ideal body weight with normal range

BMI can be obtained through acombination of diet and exercise sometabolic requirements are matched withcaloric intake. Healthy eating and physicalactivity are always the primary means toreach a healthy weight. The “Dietary

Guidelines for Americans” publishedjointly by the U.S. Department of Healthand Human Services (HHS) and the U.S.Department of Agriculture (USDA) offersguidance on developing a healthy eatingplan and tips for caloric intake (see nextsection on diet). Additionally, we haveincreasing knowledge that getting theproper amount of sleep is also importantto maintaining a healthy weight, and thatshort sleep and shift work can adverselyaffect metabolism and weight (see sleepsection page 29).

DIET

A healthy diet is an importantcomponent of preventing heart disease.In randomized controlled trials, dietaryhabits have been shown to affect manycardiovascular risk factors, such ascholesterol levels, blood pressure, glucoselevels and obesity. For example,individual nutritional determinantsassociated with adiposity or weight gaininclude larger portion sizes, higher intakeof sugar-sweetened beverages, and greaterconsumption of fast food andcommercially prepared meals.xiv

Consultation with a dietician can alsohelp personnel with designing samplemenus and healthy eating tips.The Fit to Survive (FTS) program, part of

the IAFF/IAFC Fire Service Joint LaborManagement Wellness-Fitness Initiative,was created to promote continuouseducation of fire fighters regarding healthydietary patterns and nutrition. Theworking environment of uniformedpersonnel presents unique challenges to themaintenance of healthy eating habits. TheFTS website offers expert advice andpractical information on staying fit andhealthy. The FTS menu planner providesrecipes for simple, healthy meals that canbe easily prepared on the job. The menuplanner also helps fire fighters plan aheadfor each day, week, and month, andprovides complete nutrition informationfor each recipe. Each day’s meals add up toapproximately 2,200 calories. The FTSprogram also provides information on howto make the healthiest choices when eatingon the run to help avoid fast foods that arehigh in carbohydrates, fats, and sodium.The “Dietary Guidelines for Americans,

2010” was published jointly by the U.S.Department of Health and HumanServices (HHS) and the U.S. Departmentof Agriculture (USDA). It contains

evidence-based nutritional guidance topromote health, reduce the risk of chronicdiseases, and reduce the prevalence ofoverweight and obesity through improvednutrition and physical activity.xv Keyrecommendations about food andnutrients are summarized in the followingparagraphs. Consult your physician forany questions or concerns that you mayhave about beginning a new diet.

SODIUM

Sodium, which is found in salt, is anessential nutrient, usually needed in onlysmall quantities. Generally, highersodium consumption is associated withhigher blood pressure. Evidence fromresearch documents that as sodium intakedecreases, so does blood pressure.xvi Mostpeople consume more sodium than theyneed. Sodium is added to food for

multiple reasons, such as baking,flavoring and curing meat. Most sodiumcomes from salt added to processedfoods. Individuals should reduce theirsodium intake to less than 2.3 grams aday; however, African Americans,individuals with hypertension, diabetes,or chronic kidney disease and individualsages 51 and older should limit sodiumintake to 1.5 grams a day.

FATS AND CHOLESTEROL

Fats are found in plant and animalfoods. Fats supply calories and aid in theabsorption of vitamins. Dietary

26

STEPS YOU CAN TAKE TODAY

• Read the Nutrition Facts label forinformation on the sodium contentof foods and purchase foods that arelow in sodium.

• Consume more fresh foods and fewerprocessed foods that are high insodium.

• Eat more home-prepared foods, anduse little or no salt or salt-containing seasonings when cooking or eatingfoods.

• When eating at restaurants, ask thatsalt not be added to your food ororder lower sodium options, ifavailable.

guidelines recommend that fats shouldaccount for 20% to 35% of daily caloricintake. Fats often contain a mixture offatty acids, which are categorized assaturated, trans, monounsaturated, orpolyunsaturated. The types of fatty acidsconsumed are more important inimpacting the risk of cardiovasculardisease than is the total amount of fat inthe diet. The “better” fats are unsaturatedfats. Foods from plants, except coconutoil, palm kernel oil, and palm oil, tend tohave more monounsaturated and/orpolyunsaturated fatty acids. Foods fromanimals, except seafood, tend to havemore saturated fatty acids. Most fats thathave a high percentage of saturated ortrans fatty acids are solid at roomtemperature and are referred to as “solidfats.” Solid fats are found in most animalfoods but also can be made fromvegetable oils through the process ofhydrogenation. Fats that have moreunsaturated fatty acids are usually liquidat room temperature and are referred toas “oils.” Most saturated fats that we eat come

from animals, such as beef, lamb, pork,poultry with skin, and dairy productsmade from whole or reduced-fat (2%)milk. These foods also containcholesterol. Baked and fried foods canalso have elevated levels of saturated fats.Some plant foods, such as palm oil, palmkernel oil, and coconut oil also containsaturated fats, but do not containcholesterol. Trans fats are found in manyfoods. While some trans fats are derivedfrom animal sources, most come frompartially hydrogenated fat that can befound in commercially baked productsand fried foods. There is strong evidencethat higher intake of most dietarysaturated and trans fatty acids areassociated with higher levels of bloodtotal cholesterol and low-densitylipoprotein (LDL) cholesterol, both arerisk factors for heart disease.xvi TheAmerican Heart Association recommendsindividuals should restrict their intake ofsaturated fats to less than 7 % of totaldaily calories and limit intake of trans fatsto as low as possible. This means youshould try to avoid eating foods thatcontain partially hydrogenated vegetableoils, and if you are eating foods fromanimals, try meals containing poultry,lean meats, and fish.Unsaturated fats or “good fats” can

either be monounsaturated or

polyunsaturated. Monounsaturated fatshave been used for millennia in olive oil,one of the fundamental components ofthe Mediterranean diet. Foods rich“good” fats include olive, canola,sunflower, soy, and corn oils; nuts, seeds,and fish. The American Heart Associationrecommends eating unsalted nuts,legumes and seeds at least 4 servings aweek. However, while unsaturated fats are“better” than saturated and trans fats,excessive consumption can lead tounwanted calories.Omega-3 fatty acid is a polyunsaturated

fat, which can be found in oily fish, suchas mackerel and sardines. Consumptionof omega-3 fatty acids have been shownto have a favorable cardiovascular profile.The American Heart Associationrecommends that people eat a variety offish, preferably oily fish (salmon, tuna,mackerel, herring and trout), at leasttwice a week. In addition to eating mealswith a variety of fish, individuals withcoronary artery disease or elevated serumtriglyceride levels should also consulttheir personal physicians regarding theadvisability of taking daily omega-3 fattyacid supplements.Cholesterol is a compound defined as a

waxy steroid of fat and is used in the bodyin cell membranes and hormones. Dietarysources of cholesterol are found in animalfoods. Dietary cholesterol has been shownto raise blood LDL cholesterol levels insome individuals, and moderate evidencedemonstrates a relationship betweenhigher intake of cholesterol and higherrisk of cardiovascular disease. However,this effect is reduced when saturated fattyacid intake is low, and the potential

negative effects of dietary cholesterol arerelatively small compared to those ofsaturated and trans fatty acids.xvi Totalcholesterol consumption should be < 300mg a day to help maintain normal bloodcholesterol levels, but in individuals at

higher risk of cardiovascular disease, totalconsumption should be < 200 mg a day.As an example, a medium egg has about185 mg of cholesterol and a large one hasabout 215 mg.

ADDED SUGARS

Carbohydrates are categorized as simple,including sugars, or complex, includingstarches and fibers. Some sugars occurnaturally in food, such as fruits and milk,while others are added to food for variousreasons, including sweetening the flavorof foods and for preservation purposes.Often added sugars supply calories butlittle essential nutrients or fiber. Dailyconsumption of carbohydrates shouldrange between 45% to 65% of totalcalories. The American Heart Association

recommends that no more than half ofyour daily discretionary calorie allowancecome from added sugars. Dailydiscretionary calories come from eatingfoods after daily nutrient needs arealready met, but do not contribute toweight gain. For most American women,this is less than 100 calories per day(about 6 teaspoons of added sugar) andless than 150 per day for men (about 9teaspoons of added sugar).

REFINED GRAINS

Foods that come from plants such aswheat, rice, corn or oats are grains. Thereare two main types of grain products:whole grains and refined grains. Wholegrains contain the entire grain, includingthe bran, germ and endosperm. Examplesinclude whole-wheat flour, oatmeal andbrown rice. Whole grains are a good sourceof vitamins, minerals and fiber. Dietaryfiber from whole grains helps reducecholesterol. It can be difficult to try andidentify foods with whole grains withoutlooking at the ingredient label. For manywhole-grains, the words “whole” willappear before the grain’s name in theingredient list, such as “whole grain.” Thewhole grain should be the first ingredientlisted. The American Heart AssociationWhole Grain heart-check mark on foodlabels identifies products with wholegrains. Refined grains have been milled, which

removes the bran and germ. Someexamples of refined grains are wheat flourand white rice. During the refining process

27

STEPS YOU CAN TAKE TODAY

• Consume < 7% of daily calories fromsaturated fatty acids.

• Keep trans fatty acid consumption aslow as possible.

• Consume less than 300 mg per day ofdietary cholesterol.

of whole grains, vitamins, minerals andfiber are lost. Many refined grains havevitamin and minerals added during thelater stages of refining, which return some,but not all of the beneficial ingredients. The number of recommended servings

of grains depends on your calorie needs.The recommended amount of grains thatsomeone should consume every day ismeasured as “ounce-equivalents” but iscommonly referred to as “ounces” (orservings) of grains. For example, a personwho needs to eat 2,000 calories each dayshould eat 6 to 8 servings of grains, at least

half should come from whole-grains. Therecommended amount of refined grains isno more than 3 ounce-equivalents a day,and whole grains should be added to thediet to account for at least half of all grainseaten.xvi The recommended amount offiber is 25 grams daily. A single serving ofgrains would be equal to 1 slice of bread, 1cup of cereal or ½ cup of pasta.

GENERAL TIPS FOR EATING HEALTHY

As discussed above, eating healthy meanshaving a diet containing a variety of fruits,vegetables, nuts and grain products, aswell as judicious amounts of fats.Learning how to read and understandfood labels can help you make healthierchoices. In addition to Table 6.2 thatsummarizes suggested serving sizes offoods for 1,600 and 2,000 calories a daydiets, the following are some general tipsfor healthier eating habits:

• Fruits and Vegetables: Eat a varietywith a goal of 4 ½ servings a day. Limitconsumption of potatoes, as theycontain starch, which has the samedeleterious effect on blood sugar asrefined grains and sweets.

• Grains: Choose whole grains, such aswhole wheat bread, and brown rice.Eating too much of refined grains, suchas white bread and white rice, can raisethe risk of heart disease.

• Proteins: Choose fish, poultry, beans, ornuts, which contain healthful nutrients.Limit red meat and avoid processedmeats. Keep saturated fats to <7 % oftotal calories a day.

• Oils: Use olive, canola, and other plantoils. Avoid trans fats.

• Nuts: Eat at least 4 servings of nuts,legumes and seeds a week

28

STEPS YOU CAN TAKE TODAY

• Eat foods containing fiber, with arecommended 25 grams of fiber daily.

• Eat 6 to 8 servings of grainsdaily, with no more than 3 servingsfrom refined grains.

Food Type

GrainsAt least half of yourservings should bewhole-grain.

VegetablesEat a variety of colors andtypes

FruitsEat a variety of colors andtypes

Fat-free or low-fat dairyProducts

Lean meats, poultry, and seafood

Fats and oilsUse liquid vegetable oilsand soft margarine mostoften

Nuts, seeds, andlegumes

Sweets and addedsugars

1,600 Calories

6 servings per day

3-4 servings per day

4 servings per day

2-3 servings per day

3-6 oz (cooked)per day

2 servings per day

3-4 servings per week

0 servings per week

2,000 Calories

6-8 servings per day

4-5 servings per day

4-5 servings per day

2-3 servings per day

Less than 6 oz per day

2-3 servings per day

4-5 servings per week

5 or fewer servings per week

Examples of One Serving

• 1 slice bread• 1 oz dry cereal (check nutrition label for cup

measurements of different products)• 1/2 cup cooked rice, pasta, or cereal (about the

size of a baseball)

• 1 cup raw leafy vegetables (about the size of asmall fist)

• 1/2 cup cut-up raw or cooked vegetables• 1/2 cup vegetable juice

• 1 medium fruit (about the size of a baseball)• 1/4 cup dried fruit• 1/2 cup fresh, frozen, or canned fruit• 1/2 cup fruit juice

• 1 cup fat-free or low-fat milk• 1 cup fat-free or low-fat yogurt• 1 and1/2 oz fat-free or low-fat cheese (about

the size of 6 stacked dice)

• 3 oz cooked meat (about the size of acomputer mouse)

• 3 oz grilled fish (about the size of a checkbook)

Examples of One Serving• 1 tsp soft margarine• 1 Tbsp mayonnaise• 1 tsp vegetable oil• 1 Tbsp regular or 2 Tbsp low-fat salad dressing

(fat-free dressing does not count as a serving)

• 1/3 cup or 1 and 1/2 oz nuts• 2 Tbsp peanut butter• 2 Tbsp or 1/2 oz seeds• 1/2 cup dry beans or peas

• 1 Tbsp sugar• 1 Tbsp jelly or jam• 1/2 cup sorbet and ices• 1 cup lemonade

Table 6.2 xvii

• Fluids: Drink water, tea, or coffee (withlittle or no sugar). Limit milk and dairyto 1-2 servings per day and juice to 1small glass a day. Avoid drinks withadded sugar.

ADDITIONAL NUTRITIONALINFORMATION

There are several well researched sourcesof information for those seeking to eathealthier. The American HeartAssociation publishes and maintainsonline information about nutrition,physical activity, smoking cessation andweight management. The U.S.government publishes “The DietaryGuidelines for Americans” that can befound online or ordered from the USDA.The USDA also provides resources to helpindividuals develop personalizednutrition plans, track food and physicalactivities, and get tips to support healthyeating choices. Nutrition experts at theHarvard School of Public Health inconjunction with Harvard HealthPublications have produced the HealthyEating Plate, a visual guide to help eathealthy (see Figure 6.1). The HealthyEating Plate also addresses deficiencies inthe USDA guidelines.

SLEEP HYGIENE

Sleep hygiene is a variety of differentpractices that are necessary to havenormal, quality night time sleep and fulldaytime alertness.xix Sleep hygiene isimportant for everyone and can preventthe onset of sleep disorders. Sleepdisturbances and daytime sleepiness aresigns of poor sleep hygiene. The mostimportant factor is maintaining a regularsleep and wake pattern. Most adultsrequire 7-8 hours of sleep each night.Workers will benefit from sleeping in a

dark, quiet room, at a cool andcomfortable temperature. Having aregular routine of preparing for sleep alsohelps. Night and shift workers may alsoconsider dark curtains and trying tominimize possible disturbances fromunwanted noise. Permanent nightworkers should also seek to maintain aregular sleep schedule, even on days off.Reverting to a daytime schedule whenoff-duty can make it more difficult tosleep during the day after resuming nightshifts.xx Individuals who rotate shifts canadjust their sleep schedules so they can

adapt to upcoming shift changes. Forexample, on the last few days of anevening shift, workers should delay theirbedtimes and rising times by 1 to 2 hours,so by the time they start a night shiftschedule, they have already began theprocess of adapting to the new schedule.xix

Those who staff on-call shifts faceadditional problems as they may not beable to anticipate their schedules, andmay benefit from napping if they areunable to maintain their sleep. Naps mayhelp offset some of the effects of sleepdeprivation and temporarily improvealertness, but they are not a substitute foradequate nightly sleep. Brief naps (lessthan 30 minutes) during a work shift arepreferred, as longer naps that allowdeeper sleep may briefly hinderperformance due to sleep inertia, which isthe body’s tendency to want to remain atrest between 15 minutes to an hour after

waking. Caffeine may be taken before abrief nap because it takes some time toachieve its stimulant effects and willfurther increase alertness uponawakening from the nap. This may beespecially important for those who haveto react immediately upon awakening.xix

In terms of adjuncts to a regular sleepcycle, occasional use of caffeine has beenshown to reduce sleepiness and enhancealertness, but it should not be consumedwithin 4 hours of nighttime sleep.Sleeping pills are often taken by shiftworkers, but long-term regular use is notrecommended because they do notaddress the underlying cause ofsleepiness, which is inadequate sleep.Furthermore, these drugs are notrecommended for use in public safetyworkers. Additionally, the effectiveness ofsleeping pills, such as benozodiazepinesand newer prescription sleep medications

29

Figure 6.1 xviii

can wane with time and dependencyissues can develop. In particular, peoplewith a history of addiction, or alcoholand drug abuse, are at an increased risk ofdependence from sleep aids.xxi Over thecounter sleep aids are not recommendedfor inducing sleep as many productscause prolonged drowsiness up to severalhours after awakening.xix Use of alcohol topromote sleep is also not recommended.While it can help initiate sleep, it causeslater sleep disruption as the alcohol ismetabolizes and arousal occurs.Work site conditions can also promote

alertness in shift workers. It isrecommended that workplaces be cool,with bright lighting. Healthy food choicesshould be available. Workers should avoid“junk food” including fried foods, butshould not try to go to sleep hungry orimmediately after eating a large meal.xix

Tips for Good Sleep Hygiene: xix, xx, xxi

• Try to go to bed at the same time every day

• Establish relaxing pre-sleep ritualssuch as a warm bath

• Make sure your bedroom is a quiet,dark, and relaxing environment

• Make sure your bed is comfortableand use it only for sleeping

• Try to keep a regular schedule, withregular times for eating, performingchores, etc.

• Exercise regularly, but not too close tobedtime

• Avoid large meals before bedtime.

TOBACCO

Smoking is the number-one cause ofpremature death and a significantcontributor to heart disease, lung diseaseand cancer. It causes 438,000 deaths inthe United States each year and 8.6million Americans live with serioussmoking-related illness. It is also theleading cause of fires, including fires that

have claimed the lives of IAFF members.Smokeless tobacco products, such as oraltobacco or “chew” and inhaled tobacco or“snuff”, are not safe alternatives tocigarettes. Recent evidence has implicatedsmokeless tobacco products in thedevelopment of cancer as well asreproductive health issues, includingdecreased sperm counts in men andpremature births during pregnancy.xxii

The good news is some health benefits ofquitting are immediate. Tobaccocessation, even among those who havesmoked for many years, can greatlyreduce the risk of dying from heartdisease. People who quit smoking can cutthe risk of dying from heart disease inhalf. When a smoker quits, the risk ofheart disease death begins to fall quicklyand approaches the risk of nonsmokersafter several years. Quitting also decreasesthe risk of other circulatory diseases, suchas abdominal aortic aneurysms andstrokes.xxiii

Given the many harmful effectsassociated with tobacco, the IAFF and theIAFC have adopted three main goals inour Wellness-Fitness Initiative TobaccoCessation Policy:

• All new fire department candidatesshall be tobacco free uponappointment and throughout theirlength of service to the department.

• Current fire department uniformedpersonnel shall not use tobaccoproducts inside the work-site, withinor on fire department apparatus, orinside training facilities.

• A fire department sanctioned tobaccocessation program shall be madeavailable to incumbent tobacco users.Tobacco cessation programs must benon-punitive and must include shortand long term goals.

The IAFF continues our efforts tobecome the first tobacco-free union inNorth America. This initiative encouragesIAFF members and their families to takeon healthier lifestyles by becoming smokeand tobacco free.

CONCLUSION

As a profession, fire fighters experience ahigher proportional mortality from heartdisease. Prevention is effective indecreasing the risk for developing heartdisease. Modifiable risk factors liketobacco cessation, maintaining healthyblood pressure, ideal body weight, healthydiet and regular physical activity canprevent or decrease the severity ofcardiovascular disease. The publishedfederal guidelines regardingrecommended preventive measures havean evidenced-based foundation. If theyare adopted on a widespread basis, therewill be a significant improvement in themorbidity and mortality due to heartdisease. You can lower your risk for heartdisease by following theserecommendations.

30

STEPS YOU CAN TAKE TODAY

• Visit www.iaff.org/smokefree to learnmore about becoming smoke-freeincluding:

• Information on the health risks ofsmoking and the benefits ofquitting.

• Tips on how friends and family canhelp a smoker quit.

• Information on how to encouragehealth insurance plans to make surethey cover smoking cessation.

• Consider combining cessationmedications and counseling. Thecombination of medication andcounseling is more effective forsmoking cessation than eithermedication or counseling alone.

31

i Garber CE, et al. Quantity and Quality of Exercisefor Developing and MaintainingCardiorespiratory, Musculoskeletal, andNeuromotor Fitness in Apparently Healthy Adults:Guidance for Prescribing Exercise. Medicine &Science in Sports & Exercise. July 2011. Volume 43,Issue 7, pp 1334-1359.

ii Glover MC, Leon AS. 2011 Compendium ofPhysical Activities: a second update of codes andMET values. Medicine and Science in Sports andExercise. 2011;43(8):1575-1581.

iii U.S. Department of Agriculture and U.S.Department of Health and Human Services.Dietary Guidelines for Americans, 2010. 7thEdition, Washington, DC: U.S. GovernmentPrinting Office, December 2010.

iv Soteriades ES, Smith DL, Tsismenakis AJ, BaurDM, Kales SN. Cardiovascular disease in USfirefighters: a systematic review. Cardiology inReview. 2011;19 (4):202-215.

v Joint National Committee on Prevention,Detection, Evaluation, and Treatment of HighBlood Pressure 6. NHLBI, NIH. NIH Publication98-4080. 1997.

vi Joint National Committee on Prevention,Detection, Evaluation, and Treatment of HighBlood Pressure 7. NHLBI, NIH. NIH Publication04-5230. 2004.

vii Sacks FM, Svetkey LP, Vollmer WM, et al. Effectson blood pressure of reduced dietary sodium andthe Dietary Approaches to Stop Hypertension(DASH) diet. DASH-Sodium CollaborativeResearch Group. N Engl J Med. 2001;344:3-10.

viii de Lange, et al. A hard day’s night: a longitudinalstudy on the relationships among job demandsand job control, sleep quality and fatigue. J SleepRes. 2009;18:374-383.

ix NIOSH. Stress . . . at work. U.S. DHHS (NIOSH),Cincinnati. Publication 99-101. 1999.

x Mind/Body Health: Stress. AmericanPsychological Association. Washington, DC.Accessed 10/5/12.http://www.apa.org/helpcenter/stress.aspx

xi Overweight and Obesity. Defining Overweight andObesity. U.S. Centers for Disease Control andPrevention. Atlanta, GA. Accessed 1/5/12.http://www.cdc.gov/obesity/defining.html.

xii Flegal KM, et al. Prevalence and trends in obesityamong US adults, 1999-2008. JAMA.2010;303:235-241.

xiii Vasan RS, et al. Estimated risks for developingobesity ion the Framingham Heart Study. AnnIntern Med. 2005;143:473-480.

xiv Roger VL, et al. Heart disease and strokestatistics—2011 update: a report from theAmerican Heart Association. Circulation. 2011,123:e18-e209.

xv USDA Office of Communications. Press Release:USDA and HHS Announce New DietaryGuidelines to Help Americans Make HealthierFood Choices and Confront Obesity Epidemic.USDA. January 31, 2011.

xvi U.S. Department of Agriculture and U.S.Department of Health and Human Services.Dietary Guidelines for Americans, 2010. 7thEdition, Washington, DC: U.S. GovernmentPrinting Office, December 2010.

xvii Suggested Servings from Each Food Group. TheAmerican Heart Association. Dallas, TX. Accessed1/5/12.http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/HealthyDietGoals/Suggested-Servings-from-Each-Food-Group_UCM_318186_Article.jsp.

xviii Copyright © 2008 Harvard University. For moreinformation about The Healthy Eating Pyramid,please see The Nutrition Source, Department ofNutrition, Harvard School of Public Health,http://www.thenutritionsource.org, and Eat,Drink, and Be Healthy, by Walter Willet, M.D. andPatrick J. Skerrett (2005), Free Press/Simon &Schuster Inc.

xix Michael Thorpy. Sleep Hygiene. Sleepmatters.Spring 2003.

xx American Sleep Disorders Association. Copingwith Shift Work. Washington, DC. 1994.

xxi Zee PC, et al. Sleeping Smart Myths and Facts. TheNational Sleep Foundation. Accessed February 28,2012.http://www.sleepfoundation.org/sleep-facts-information/myths-and-facts.

xxii World Health Organization. Smokeless Tobaccoand Some Tobacco-Specific N-Nitrosamines.International Agency for Research on CancerMonographs on the Evaluation of CarcinogenicRisks to Humans Vol. 89. Lyon (France): WorldHealth Organization, 2007.

xxiii U.S. Department of Health and Human Services.The Health Benefits of Smoking Cessation: AReport of the Surgeon General . Atlanta: U.S.Department of Health and Human Services,Centers for Disease Control and Prevention,Center for Chronic Disease Prevention and HealthPromotion, Office on Smoking and Health, 1990.

32

Heart Disease in the Fire ServicecHaPter 7 • Heart disease and fire figHter Benefits

The International Association of FireFighters has been addressing the issues offire fighters and cardiovascular disease fordecades. The IAFF has protected ourmembers by pursuing enactment oflegislation that provides protection andcompensation for those fire fighters whosehealth has deteriorated through theperformance of their firefightingoccupation. These laws have ranged fromfederal legislation, to providecompensation for the families of those firefighters who die or are severely disabled inthe line-of-duty, to state and provinciallegislation extending retirement and/orworker compensation benefits to thosewho become disabled from occupationallycontracted diseases.

FIRE FIGHTING ENVIRONMENT

Fire fighters, like most workers, have littleidea about the identity of many of thematerials they are potentially exposed to orthe hazards of such exposures.Nevertheless, fire fighters continue torespond to the scene and workimmediately to save lives and reduceproperty damage without regard to thepotential hazards that may exist. A fireemergency has no controls or occupationalsafety and health standards to reduce theeffect of toxic chemicals. It is anuncontrollable environment that is foughtby fire fighters using heavy, bulky andoften times inadequate personal protectiveequipment and clothing. The effect is notonly physically demanding, but involvesexposure to air contaminants, some ofwhich are known to cause diseases of thecardiovascular system.The fire fighting profession illustrates the

selective impact of past safety and healthinitiatives. Despite the advances made insafety and health areas, fire fighters are stillbeing killed, injured and diseased at analarming rate. Professional fire fightershave inordinate numbers of line-of-dutydeaths, deaths due to occupationaldiseases, forced retirements, andline-of-duty injuries.

IAFF POSITION ON HEART DISEASE

It is the position of the IAFF thatcardiovascular disease is exacerbated byfire fighting duties, and that fire fightingincreases the incidence of cardiovasculardisease in fire fighters. Fire fighters andemergency medical personnel face thepossibility of death or injury every timethey respond to an alarm. While risk maybe part of the profession, fire fighter andemergency medical personnel deaths,injuries, and occupational diseases shouldnot be part of the job.

STATE AND PROVINCIAL HEARTDISEASE PRESUMPTIVE LAWS

Presumptive disability laws state thatspecific diseases or conditions arepresumed to come from an individual’soccupation. In recognition of the causalrelationship between fire fighting andheart disease, 37 states and seven provinces(shown below in Table 7.1) have adoptedpresumptive laws to provide disabilitybenefits to fire fighters diagnosed withcardiovascular disease and relatedconditions. These laws presume thatcardiovascular disease is occupationallyrelated to fire fighting. Consequently, theirprovisions shift the burden of proof fromthe employee to the employer todemonstrate that the disease or conditionwas not in fact associated with theoccupation but with another cause. A firefighter diagnosed with heart diseasecovered by a presumptive disability lawwould be entitled to:

• Payment of medical expenses

• Disability retirement benefits

• Workers’ compensation benefits

• Lost wages or benefits for spouse and/orfamily

The benefits provided by presumptivedisability laws vary between states andprovinces. Additionally, many workers’compensation boards in Canada and theU.S. have established a history ofidentifying heart disease in fire fighters asemployment-related. While all these lawsrecognize heart disease as occupationallyrelated to fire fighting, some haveexclusions and prerequisites for obtainingbenefits. Many states and provincesrequire a minimum number of years ofservice before a condition or illness ispresumed to be associated with firefighting. Some laws also include rebuttalclauses that allow employers to challengethe job relatedness of a condition orillness. In this case the employer mustdemonstrate that the condition or illnessdid not arise from the occupation of firefighting but from some other cause. It isalso important to remember that despitethe presence of presumptive legislation,there is still no guarantee that the claimwill be approved. The IAFF maintains full copies of all state

and provincial laws or regulations and thenumber of worker compensation awardsfrom the United States and Canada thataddress heart disease. The IAFF alsoprovides assistance and information toobtain or maintain heart disease legislationand regulations.

PROVINCES WITH PRESUMPTIVE HEART LAWS

Alberta*

Manitoba

New Brunswick*

Ontario

Saskatchewan

Yukon*

Northwest Territories

33

STATES WITH PRESUMPTIVEHEART LAWS

* covers myocardial infarction/heartattack only

The following section summarizes thedifferent laws and benefit programsestablished in the U.S. for families of firefighters who are killed or permanentlydisabled from injuries sustained while inthe line of duty. The IAFF Division ofOccupational Health, Safety andMedicine will provide our affiliates andthe fire fighter’s family with assistance infiling for these benefits.

PUBLIC SAFETY OFFICER BENEFITS ACT

The Public Safety Officers Benefits(PSOB) Act (Public Law 94-430) becamelaw on September 29, 1976. Thelegislation provided for a $50,000 deathbenefit for fire fighters (paid andvolunteer) and law enforcement officerswho died in the line of duty (emergencyor non-emergency) from a traumaticinjury. The Act does not cover deathsresulting from occupational illness orpulmonary disease unless a traumaticinjury is a substantial factor to the death.

The PSOB Act has since been amended toincrease the benefit amount each year toreflect any increase in the consumer priceindex. On October 26, 2001, as part ofthe Patriot Act of 2001, the benefit wasincreased to $250,000 and maderetroactive to January 1, 2001.The Act did exclude federal fire fighters;

however on October 12, 1984 the Act wasamended to correct this exclusion.Likewise, on October 15, 1986 publicsector EMS personnel were also amendedinto the coverage of the Act. On June 25,2002, the Act was amended by theenactment of the Mychal Judge Police andFire Chaplains Safety Officers Benefit Act,which allows coverage of fire chaplainsunder the Act and authorizes allbeneficiaries of fallen fire fighters, not justparents, spouses or children to receivefederal compensation.

PSOB DISABILITY AMENDMENT

On November 29, 1990, Congressamended the PSOB Act to includepermanent and total disability. Theamendment was tightly drawn, sharplylimited in scope, and intended to coveronly those public safety officerspermanently unable to perform anygainful employment. The PSOB disability amendment

recognizes that state, local and agencybenefit programs are primarilyresponsible for the hundreds, perhapsthousands, of public safety officerdisability pensions awarded each year.The PSOB Act is clear that benefitsawarded are supplementary in nature andby law are not to offset any workercompensation payment or disabilitypension benefit. Even when an officer isdisabled by a severe, catastrophic injuryreceived in the line of duty, PSOB benefitsdo not come into play unless the injuriesare so disabling as to permanently preventany gainful employment. This standardrecognizes that in all but rare cases adisabled public safety officer will have thecapacity to supplement a state or localdisability pension with employmentearnings of varying degrees.On August 10, 2006 new regulations for

the PSOB were issued that incorporatedall prior amendments to the originalregulations and added the regulations forthe Hometown Heroes Act.

HOMETOWN HEROES SURVIVORS BENEFITS ACT

The Hometown Heroes SurvivorsBenefits Act of 2003 (HHA) amended thePSOB Act to cover deaths from heartattack and stroke that occur in theline-of-duty. The HHA establishes thepresumption that public safety officerswho suffer a fatal heart attack or strokeup to 24 hours, after engaging in a line ofduty activity or formal training exercisethat required non-routine stressful orstrenuous physical activity, died as adirect and proximate result of a personalinjury sustained in the line of duty.

The HHA defines “non-routine stressfulor strenuous physical activity” as:

• Activity that is not performed as amatter of routine.

• Entails an unusually high level ofphysical exertion.

• Engaging in line of duty activities thatpose or appear to pose significantthreats or involves reasonabilityforeseeable risks of threats.

• Participating in training exercises thatrealistically stimulate significantthreats or hazards.

• Provokes or causes an unusually highlevel of alarm, fear, or anxiety.

The HHA specifically excludes fatalitiesrelated to activities of a clerical,administrative, or non-manual nature.The HHA provision only covers deathsoccurring on or after December 15, 2003and is not retroactive; therefore it doesnot apply to deaths occurring before theaforementioned date.

POLICE, FIRE AND EMERGENCYOFFICERS EDUCATIONALASSISTANCE ACT

The Police, Fire and Emergency OfficersEducational Assistance (PSOEA) Act wassigned into law in October 1998. The lawwas created to provide financial assistancefor higher education to the dependents offederal, state, and local public safetyofficers who are killed or permanentlyand totally disabled as a result oftraumatic injury sustained in the line of

Alabama

Alaska

California

Connecticut

Florida

Georgia

Hawaii

Idaho

Illinois

Louisiana

Maine

Maryland

Massachusetts

Michigan

Minnesota

Missouri

Nebraska

Nevada

Ohio

Oklahoma

Oregon

South Carolina

South Dakota

Tennessee

Texas*

Utah

Vermont

34

duty and eligible for the PSOB death ordisability benefit. This is the only federallyfunded program that provides educationalbenefits for the spouse and children of firefighters killed in the line of duty. ThePSOEA program is administered by theU.S. Department of Justice’s Office ofSpecial Programs. This assistance is only available after the

PSOB death or disability claim process hasbeen completed and benefits have beenawarded. Further, the PSOEA applicantmust have received at least a portion of thePSOB benefits and be defined as theofficer’s spouse or child under the PSOBAct and regulations. In January 2000, thelaw further extended the retroactiveeligibility date for financial assistance.Accordingly, the law applies to the spousesor children of public safety officers whosedeaths or permanent and total disabilitiesare covered by the PSOB Program on orafter January 1, 1978. Public safety officers’children will no longer be eligible aftertheir 27th birthday, absent a finding by theAttorney General of extraordinarycircumstances. The PSOEA Program willprovide an educational assistanceallowance, which may be used solely todefray educational expenses, includingtuition, room and board, books, supplies,and education-related fees or costs.Finally, the IAFF has been attempting to

secure public safety officer benefits forCanadian fire fighters. The IAFF supportsthe creation of a federally funded PSOB inCanada which at this time has not beenaccepted at the federal level by anyministry. However, the establishment ofsuch a fund is well within the purview ofthe federal government, and the IAFFcontinues to work towardsimplementation.

SUMMARY OF LEGISLATION

The following summarizes legislationand precedent court cases that affected thelaw:

• Beverly Morrow, et al. v. The UnitedStates. U.S. Court of Claims case inwhich a fire fighter’s widow soughtbenefits following the death of herhusband of a heart attack six weeks afteran initial attack associated with a smokeinhalation incident. Benefits weredenied as death was attributed to heartdisease.

• Hubert Smykowski, et al. v. TheUnited States. U.S. Court of Claimscase in which a police officer died aftera struggle with a suspect. Court upheldthe Administrators ruling that the stressand strain of a struggle was not atraumatic injury as defined by thePSOB Act.

• Carrie Rose, etc. v. Arkansas StatePolice. The U.S. Supreme Court ruledthat any law that authorizes a state tooffset state worker compensationbenefits against benefits paid by theFederal PSOB program is in conflictwith the supplementary nature of thePSOB Act and is therefore invalid underthe supremacy clause of the U.S.Constitution.

• Public Safety Officers’ Benefits Act of1976, Part J. Original act detailing theprovision of death benefits. Introducedto the 94th Congress, September 29,1976.

• Federal Register, May 6, 1977, Part II.The rules adopted by the Law

• Enforcement Assistance Administrationfor implementation of the PSOB Act arewritten.

• Federal Register, Vol. 43, No. 180 -September 15, 1978. Results of meetingdetailing the contribution of carbonmonoxide and heart disease in thedeaths of public safety officers.

• Federal Register, Vol. 45, No. 51 - March13, 1980. Amendments to the hearingand appeal provisions of theregulations.

• Federal Register, Vol. 50, No. 128, July 3,1985. An amendment to the PSOB Actwhich transfers the administration ofthe Act from the LEAA to the Bureau ofJustice Assistance. In addition, federalpublic safety officers are now coveredunder the act and “gross negligence”and “intoxication” standards aredefined within this amendment.

• Federal Register, Vol. 53, No. 50, March15, 1988. Amendment to the PSOB Actwhich includes provision of deathbenefit coverage to members of publicrescue squads or ambulance crews. Also

an explanation of EMS coverage incorrespondence from the U.S.Department of Justice.

• Federal Register, Vol. 57, No. 113, June11, 1992. Amendment to the PSOB Actto include coverage for disabilitybenefits. Such disability is defined aspermanent and total as a direct result ofa catastrophic personal injury sustainedin the line of duty which will prevent anindividual from performing any gainfulwork.

• Public Law 107-37 - September 18,2001, [115 STAT. 219]. Amendment tothe PSOB Act to provide for theexpedited payment of PSOB benefits fora public safety officer who was killed orsuffered a catastrophic injury producingpermanent and total disability as adirect and proximate result of apersonal injury sustained in the line ofduty in connection with the terroristattacks of September 11, 2001.

• Public Law 107-56 - October 26, 2001,[115 STAT. 369]. Amendment to thePSOB Act to provide for the expeditedpayment of PSOB benefits for a publicsafety officer who was killed or suffereda catastrophic injury producingpermanent and total disability as adirect and proximate result of apersonal injury sustained in the line ofduty in connection with prevention,investigation, rescue, or recovery effortsrelated to any terrorist attack. Increasesthe PSOB program benefit payment to$250,000 retroactive to January 1, 2001.

• Public Law 107-196 - June 24, 2002,[116 STAT. 719]. Amendment to thePSOB Act to include coverage of firechaplains and allows all beneficiaries offallen fire fighters, not just parents,spouses or children to receive thefederal compensation.

• Public Law No: 108-182 December 15,2003 [117 STAT. 2649]. Amendment tothe PSOB Act to ensure that a publicsafety officer who suffers a fatal heartattack or stroke while on duty shall bepresumed to have died in the line ofduty for purposes of public safetyofficer survivor benefits. The legislationwas entitled the Hometown Heroes Act.

35

• Public Law 109–162 January 5, 2006[119 STAT. 2960, 3120]. Amendment tothe PSOB Act contained in the DOJReauthorization Act and containsseveral clarifying and conformingchanges. New definitions included theterm ‘‘member of a rescue squad orambulance crew’’ that is now defined as‘‘an officially recognized or designatedpublic employee member of a rescuesquad or ambulance crew.’’ It alsoamended the PSOB Act to ensure thatthe pre-existing statutory limitation onpayments to non-civilians referred tothe individual who was injured orkilled, and not to any potentialbeneficiaries. Finally, this legislationamended certain provisions of thePSOB Act regarding designation ofbeneficiaries when the officer dieswithout a spouse or eligible childrenand removed the need for a one-yearwaiting period to ensure payment to thebeneficiary of the officer’s ‘‘mostrecently executed life insurance policy.’’

• Federal Register, Vol. 71, No. 154, August10, 2006. The new regulations foradministration of all PSOB benefits thatincorporated all prior amendments tothe original regulations and added theprovisions of the Hometown Heroes Act.This document addresses the PSOB Actand regulations in five parts. The firstpart of this document describes thestructure and background of the PSOBProgram and aspects of the history of itsadministration. The second part coversthe recent changes to the PSOB Actcontained in Public Law 109–162. Thethird part addresses the commentsreceived by BJA that relate to theproposed provisions implementing theHometown Heroes Act, and explains thechanges being made in the final rule. Thefourth part is a specific discussion of theterms ‘‘line of duty’’ and ‘‘authorizedcommuting.” The last part addresses theremainder of the comments in asection-by-section analysis, indicatingwhere changes to provisions were made,or where BJA determined no changeswere necessary. n