Translational epidemiology

Venkat Narayan, K. M. et. al Diabetes Care. 2000; 23:1794-8

Translation research for chronic disease: the case of diabetes

Translation research for chronic disease

Diabetes Care. 2000; 23:1794-8

Diabetes mellitus

• Diabetes is a “wonderful” affliction• not very frequent among men• being a melting down of the flesh and limbs into

urine. – patients never stop making water – disease is chronic – long period to form – death speedy– Life is disgusting and painful; thirst unquenchable;

excessive drinking, • Its cause is of a cold and humid nature as in

dropsy Aretaeus the Cappadocian (c. AD 30-90)

Diabetes mellitus: a clinical syndrome (signs and symptoms)

w3.ouhsc.edu/phar5442/Lectures/Diabetes.html

Diabetes mellitus: a clinical syndrome

ADA criteria for the diagnosis of diabetes mellitus: Case definition

In the absence of unequivocal hyperglycemia, these criteria should be confirmed by repeat testing on a different day. The third measure (OGTT) is not recommended for routine clinical use.

1. Symptoms of diabetes plus casual plasma glucose concentration ≥  200 mg/dl (11.1 mmol/l). Casual is defined as any time of day without regard to time since last meal. The classic symptoms of diabetes include polyuria, polydipsia, and unexplained weight loss.OR

2. FPG ≥ 126 mg/dl (7.0 mmol/l). Fasting is defined as no caloric intake for at least 8 h.OR3. 2-h postload glucose ≥ 200 mg/dl (11.1 mmol/l) during an OGTT. The test should be performed as described by WHO, using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water.

Banting, FG, Best CH. The internal secretion of the pancreas. J Lab Clin Med, 1922; 7:467-468

Insulin

Insulin is secreted by the pancreatic islet beta cell

Incidence of Diagnosed Diabetes per 1,000 Population Aged 18–79 Years, by Age, United States, 1980–2010

From 1980 through 2010, the incidence of diagnosed diabetes increased in adults aged 18–44 years and adults aged 65–79 years. Among adults aged 45–64 years, incidence of diagnosed diabetes showed little change during the 1980s, but increased beginning in the 1990s through 2010

Centers for Disease Control and Prevention

Crude and Age-Adjusted Incidence of Diagnosed Diabetes per 1,000 Population Aged 18–79 Years, United States, 1980–2010

From 1980 to 2010, the crude incidence of diagnosed diabetes increased 161% from 3.3 to 8.6 per 1,000 population. Similarly, the age–adjusted incidence increased 140% from 3.5 to 8.4 per 1,000 population, suggesting that the majority of the change was not due to the aging of the population. However, from 1980 to 2010, incidence did not increase at a constant rate. Both crude and age–adjusted incidence remained unchanged in the 1980s, and then increased in the 1990s through 2010. From 2008 through 2010, both crude and age–adjusted incidence has shown little change.

Centers for Disease Control and Prevention

Estimated prevalence of diagnosed and undiagnosed diabetes in people aged 20 years

or older, by age group, United States, 2007

2.6

10.8

23.8

0

5

10

15

20

25

20-39 40-59 60+Age Group

Perc

ent

CDC. National Diabetes Fact Sheet, 2007.Source: 2003–2006 National Health and Nutrition Examination Survey estimates of total prevalence (both diagnosed and undiagnosed) were projected to year 2007.

Crude and Age-Adjusted Percentage of Civilian, Noninstitutionalized Population with Diagnosed Diabetes, United States, 1980–2010

From 1980 through 2010, the crude prevalence of diagnosed diabetes increased by 176% (from 2.5% to 6.9%). During this period, increases in the crude and age-adjusted prevalence of diagnosed diabetes were similar, indicating that most of the increase in prevalence was not because of changes in the population age structure.

Centers for Disease Control and Prevention

0

10

20

30

40

50

60

Men Women

Perc

ent

Total Non-Hispanic WhiteNon-Hispanic Black Hispanic

Narayan et al, JAMA, 2003

Estimated lifetime risk of developing diabetes for individuals born in the United States in 2000

Complications of diabetes mellitus

Diabetic ketoacidosis and hyperosmolar (nonketotic) coma

Heart disease and stroke• Heart disease and stroke: 65 percent of deaths in diabetics.

– Heart disease death rates about 2 to 4 times higher – Stroke risk 2 to 4 times higher

Blindness• Diabetes is the leading cause of new cases of blindness among adults and causes

12,000 to 24,000 new cases of blindness each year.

Kidney disease• Diabetes is the leading cause of kidney failure, accounting for 44 percent of new

cases in 2002.

Nervous system disease• About 60 to 70 percent of diabetics have mild to severe forms of nerve damage.

– impaired sensation or pain in the feet or hands– Amputation

Some characteristics of chronic diseases• Person

– Multiple, non-specific risk factors– Disability prominent– Impact on quality of life important– Primary, secondary and tertiary prevention

• Time– Duration of disease– Epidemic curve – Long latency– Fetal/childhood origin– Time dependency of risk factors

• Place– Asynchrony of epidemic in different populations

• Societal– Expensive half-way technologies

• Medication• Organ replacement therapy

Risk factors for Type 2 DM: Multifactorial etiology

• Familial/Genetic predisposition– Identical twin: High concordance (~100%)– Sib: Moderate concordance (~30%)

• Fetal origins hypothesis • Gender/gestational diabetes • Race• Obesity• Sedentary lifestyle

Long latency

Risk factors for diabetes over the life course

advanced glycation end (AGE) products Hg A1c

Measuring glucose control

Effect of intensified glycemic control on the risk for any type of macrovascular event in type 1 and type 2 DM: RCTs

Am Heart J. 2006;152:27-38.

EBM clinical practice guidelines:American Diabetes Association.Standards of medical care in diabetes. Diabetes Care 2004; 27 (Suppl. 1): S15–34

Amundson GM, O'Connor PJ, Solberg LI, Asche SE, Woods RC, Parker ED, Crain AL. Diabetes care quality: insurance, health plan, and physician group contributions. Am J Manag Care. 2009 Sep;15(9):585-92.

• Increase • diagnosed diabetes• who receive formal diabetes education• glycosylated hemoglobin at least twice a year• annual dilated eye examination•annual foot examination•annual dental examination•self-blood-glucose-monitoring at least once /day

• Reduce•diabetes death rate. •lower extremity amputations•Undetected microalbuminuria

Healthy People 2020: Objectives Retained From Healthy People 2010

Healthy People 2020: New and modified Objectives

• Reduce •the annual number of new cases of diabetes•the diabetes death rate

•Among diabetics improve •glycemic control•blood pressure control•lipid control

•Increase % engaged in diabetes prevention behaviors among at-risk population

Copyright restrictions may apply.

Shojania, K. G. et al. JAMA 2006;296:427-440.

Community interventions:Postintervention Differences in Serum HbA1c Values After Adjustment for Study Bias and

Baseline HbA1c Values