Hypertension

By Alexandre Sloukgi

More than ¼ of the world’s population is hypertensive

Africa

Europe

Oceania

Asia

America

Worldwide

0% 5% 10% 15% 20% 25% 30% 35%

33%

29%

26%

25%

22%

27%

2World Health Organization, 2012. (http://www.who.int/gho).

Hypertension: a growing disease

Kearney PM, Whelton M, Reynolds K, Muntner P, Whelton PK, He J. Lancet. 2005;365(9455):217-223.

2000 20250

200400600800

10001200140016001800

972 M

1560 M

Num

ber

of h

yper

tens

ives

(m

illio

n)

•Increased population

•Increased life-expectancy

+60%

Risk factors•Obesity•Diabetes•…

Hypertension: a growing disease

Kearney PM, Whelton M, Reynolds K, Muntner P, Whelton PK, He J. Lancet. 2005;365(9455):217-223.

2000 20250

200400600800

10001200140016001800

972 M

1560 M

Num

ber

of h

yper

tens

ives

(m

illio

n)

•Increased population

•Increased life-expectancy

+60%

Risk factors•Obesity•Diabetes•…

Prevalence: 26%

Prevalence: 30%

DefinitionChronic medical condition in which the blood

pressure of the arteries is persistently elevated.

Arterial hypertension example:

Systolic blood pressure(SBP)= 158mmHgDiastolic blood pressure(DBP)=99mmHg

While normal blood pressure: 120/80 mmHg

Signs and symptoms

Headaches, lightheadedness, vertigo, tinnitus(buzzing or hissing of the ears), fainting episodes.

Hypertensive crisis: severe elevated blood pressure(180/110) is categorized as hypertensive emergency or urgency according to presence or absence of end organ damage.

Pathophysiology1. Renin-angiotensin system : Ang II acts on

musculature of arteries and raises resistance=> blood pressure.

2. Endothelial dysfunction3. Autonomic nervous system: regulating

peripheral vasculature and kidney function. Excessive activity of sympathetic nervous system increases blood pressure=> hypertension

Risk factors Age Heredity Gender(male) Obesity

Smoking High cholesterol Diabetes Physical inactivity

EtiologyPrimary hypertension :

BP rises with aging mostly.

Environmental factors that influence :Stress, depression...

Events in early life can influence as well :low birth weight, maternal smoking.

Secondary hypertension :results from identifiable cause :

Kidney disease (most common)

Endocrine conditions such as :hyper/hypothyroidism, hyperaldosteronism,

hyperparathyroidism

Other causes: illegal drugs, pregnancy, obesity, sleep apnea, narrowing of aorta

Consequences of hypertension

End organ damage

Prevention Maintain normal body weight Reduce dietary sodium(<6g of NaCl/day) Engage in physical activities(>30 mins/day) Limit alcohol consumption (2-3 units/day =>

20-30 mL of pure alcohol /day ) Consume a diet rich in fruit and vegetables (at

least 5 portions a day)

Treatment

Dietary program for patients: limiting wine, meat, pastries, low-energy diet

Antihypertensive agents : calcium channel blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers and renin inhibitors, beta blockers, diuretics.

ACE inhibitors: a complete mode of action on RAAS and kallikrein-kinin system

Ang II

VasodilationAntiremodeli

ngAntioxidant

Antithrombotic

Ang I

Renin Angiotensin

AT1 AT2

ChymasesCathepsin G

CAGE

Dominyak and Unger (eds) in Ang II-AT1- Receptor Antagonists. Steinkopff ;1997.

Inactive peptides

Bradykinin

ACEinhibitor

Sartan

++

+

Effective 24 h bloodpressure control

Controls central aorticblood pressure

Prevents cardiacremodeling

Corrects left ventricularhypertrophy

Restores endothelialfunction

Early prevention ofatherosclerotic plaques

Reduces arterialstiffness

Stiff artery Elastic artery

References

https://www.drinkaware.co.uk/understand-your-drinking

http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/WhyBloodPressureMatters/Why-Blood-Pressure-Matters_UCM_002051_Article.jsp