Hypertension updateWhich guideline to

follow? 

Dr Sunita DodaniDepartment of Family

MedicineAga Khan University

Karachi, PakistanFebruary 23,2003

Presentation outline World Wide Epidemic: Some Figures Epidemiological Transition &

Hypertension Data From Developing Countries EMRO Work Statistics From Pakistan: NHSP Hypertension Guidelines

Currently available guidelines Similarities in guidelines Differences in guidelines

Presentation outline

Hypertension Guidelines (Cont’d)

Still Unanswered Questions What is needed in Pakistan Epidemiologic research Which guideline to follow? JNC VI guideline (1994) Risk stratification

Worldwide Epidemic: Some Figures affect all ages, but primarily occurs in

adults.20% prevalence,approximately 690m

people have hypertension world wide major risk factor for stroke, coronary

heart disease and kidney failure 30% of deaths worldwide (15 million) are

due to cardiovascular diseases 5 million deaths / year worldwide due to

strokes alone, with another 30 million suffering from its disabling effects.

(Geneva, Switzerland November 15-16, 1999)

Epidemiological Transition & Hypertension

 Developing countries experiencing rapid health transition, escalating relative and absolute burdens of CVD

Determinants of transition a) demographic (increased life expectancy)b) lifestyle changes c) urbanization, industrialization and

globalization

Epidemiological Transition & Hypertension (Cont’d)

In developing countries ,steady increase in hypertension prevalence over the last 50 years, more in urban than in rural areas (WHO report 2002)

WHO Regions

World regions according to WHO

•

Eastern Mediterranean region (EMR)

(Jordan, Iran, Srilanka, Pakistan, Egypt Oman, Saudi Arabia , Bangladesh etc)

Paucity of large, authentic, epidemiological studies

Limited data available in the form of small studies

Majority of studies done have shortcomings

differing examination techniques differing diagnostic criteria

screening blood pressure values used

The studies are not representative of the total population Limited to single centers or single community

EMR (cont'd…)

Majority of third world countries lack sufficient national estimates of the prevalence of hypertension

In developing countries ,steady increase in hypertension prevalence over the last 50 years, more in urban than in rural areas

EMR…. Some prevalence figuresSaudi Arabia 10-15%

(EMRO bulletin 2001)

Riyadh city 15.4% (27% unaware)Bangladesh (> 70 yrs) 65%

(multi center trail, hypertension study group, 2000)

Egypt (national estimates) 26%> 70 yrs 56.6% (Ibrahim MM , Cairo university Egypt, 1998)

Iran(population based) 18% (Sarraf-Zadegan N, East Mediterr Health J 1999)

Hypertension figures in Pakistan

National Health Survey of Pakistan 1990-1994

Some data available, some in re-analysis phase10.8 million hypertensives (pop 91m,1991)

5.5 million men5.3 million women

12 million hypertensives (pop 130m,1998)

17.9% ( 15 yrs)21.5%………….. Urban16.2%………….. Rural

Hypertension figures in Pakistan NHSP ( 1990-1994)58% ( 65 yrs females)1 in every 3 Pakistanis (>45 yrs)Prevalence is lower in females than

males at younger ages, but exceed after 35-44 yrs of age

(This cross over is at later age in US population)

>3% of the hypertensive patients have BP controlled to the conventional recommendations of under 140/ 90 mmHg

Hypertension figures in Pakistan

Prevalence of hypertension (PMRC)

Rural

0

10

20

30

40

50

60

15-24 25-34 35-44 45-64 65+

Female

Male

Hypertension figures in Pakistan

Prevalence of hypertension (PMRC)URBAN

0

10

20

30

40

50

60

15-24 25-34 35-44 45-64 65+

Female

Male

Early detection,awareness & treatment

(Need for guidelines)help to limit the subjective element in

decision making & assist clinicians to provide better care

define the best clinical decisions and the minimal level of acceptable care in order to ensure appropriate quality

formulated based upon the evidence collected from available literature, and agreement among experts in areas where literature is deficient

Hypertension Guidelines Several guidelines for the management of

hypertension were published in the last few years

Many were recent revisions and updated versions of old ones, modified according to new evidence from clinical trials

Provided answers to many clinical questions. a) Isolated systolic hypertension in the

elderly is dangerous & should be treated

b) aggressive lowering of blood pressure is

required in patients with risk factors

Hypertension GuidelinesJNC VI 1994 {Hypertension Detection and Follow-up Program (HDFP)}

WHO/ISH 1999British hypertension Society 1999

{Medical Research Council (MRC)}

Canadian Cardiac Society 1999

LocalPakistan hypertension league 1998(First Report of National Task Force)

Hypertension Guidelines

These four major guidelines are based on the strong evidence from almost the same literature and the large randomized mega trials, they agree and disagree on a number of important issues

Hypertension GuidelinesThese guidelines agree on many

aspects1. All guidelines agree upon the definition

of hypertension.

2. The type of routine tests needed for the evaluation of hypertensive patients

3. The need for global risk assessment & the target blood pressure

4. The importance of life style modification5. Individualization of antihypertensive

therapy6. Need for indefinite follow-up

Hypertension GuidelinesDifferences in the guidelines

JNC VI 1994 WHO/ISH 1999

BHS 19991. Drug therapy in mild hypertensives if BP remains 140/90 after non pharmacological treatment

Continuing monitoring without medication for subjects without other risk factors if pressures are not greater than 150/95 mm H

Add drug therapy if BP is greater than 160/90

2. Recommend diuretics or B-blocker as initial drug therapy

all classes of medication are suitable initial therapy, despite the lack of morbidity and mortality data

Diuretics as first line therapy

Hypertension GuidelinesStill Unanswered Questions how to avoid over treatment of patients at very

low risk? what is the best simple approach for accurate

cardiovascular risk assessment? Decisions to initiate therapy are based on the

absolute cardiovascular risk profile of the hypertensive patient ? risk assessment are based on the Framingham data? risk scoring equations are incomplete & complicated? do not account for racial and genetic differences.

Hypertension Guidelines

Still Unanswered Questions management of patients with

uncomplicated mild hypertension

? duration period of observation

? the number of office visits? blood pressure measurements

? the average blood pressure threshold during the period of monitoring

role of ambulatory blood pressure is not settled

how to adjust for racial, genetic, geographic, age gender and socioeconomic differences

Hypertension GuidelinesStill Unanswered Questions optimal blood pressure reduction ? what is the desired level of blood pressure

? It is not necessarily the same level in all individuals.

? Race, age and gender may influence our target blood pressure.

? We might need more aggressive reduction in blood pressure in special groups, e.g.,

diabetics, blacks and patients with end-organ damage.

Hypertension GuidelinesPopulation data:Priorities in

Epidemiologic research define the magnitude of the hypertension

problem in Pakistan with evidenced based data

prevalence among different age groups, geographic areas, socioeconomic classes and the influence of factors like gender, ethnicity

Its risk factors e.g. Obesity, excessive salt intake, alcohol intake, psychosocial stress, low levels of education, poor SES, should be recognized & examined

Hypertension Guidelines

Epidemiologic research the type and prevalence of hypertensive

cardiovascular complications. might be influenced by environment, race and other demographic characteristics

identify the susceptible groups which are most vulnerable to complications

How close are these complications related to the level of blood pressure and what are the other mechanisms involved

develop methods to improve detection and control of hypertension

Hypertension Guidelines

which guideline to follow?Considering several meta analysisoutcome data from major clinical

trial

strongest outcome data support the JNC VI recommendations

Hypertension GuidelinesTable 1 – Classification of Blood Pressure*

CategorySystolic(mm Hg)

Diastolic(mm Hg)

Normal Values of Blood Pressure**Optimal less than 120 less than 80

Normal less than 130 less than 85

High normal 130 - 139 85 - 89Stages of Hypertension**

Stage 1 (Mild) 140 - 159 90 - 99

Stage 2(Moderate) 160 - 179 100 - 109

Stage 3 (Severe) 180 or higher 110 or higher

*

Hypertension GuidelinesRisk factors stratification

In populations & in individual patients, the benefit from antihypertensive treatment is determined by the absolute cardiovascular risk

Blood pressure by itself is a very weak predictor of risk or benefit from treatment

simple but accurate risk assessment tools for estimating cardiovascular risk, similar to that in the New Zealand guidelines

Hypertension Guidelines

Presentation available at

http://www.pitt.edu/~super1&

http://www.pitt.edu/~super1/pakistan/pakistan.htm

Presentation references1. Ramsay LE. Williams B, Johnston GD, et al.

Guidelines for management of hypertension: report from the third working party of the British Hypertension Society. J Hum Hypertens 1000; 13:569-592.

1. Fieldman RD, Campbell N, Larochell P. Burgess ED, et al. 1999 Canadian recommendations for the management of hypertension CMAJ 1999; 161 (12 suppl): S1-S17

1. Joint National Committee on Prevention, Detection, Evaluation, and treatment of High Blood Pressure. The Sixth report. Arch Intern Med 1997; 157:2413-2446.

Presentation references• Carretero OA. Oparil S. Essential hypertension

Part II: treatment. Circulation 2000; 101:446-453.

• Reddy KS. Implementation of international guidelines on hypertension: the Indian experience.Clin Exp Hypertens. 1999 Jul-Aug;21 (5-6):693-701.

• O’Brien E. Critical appraisal of the JNC VI, WHO/ISH and BHS guidelines for essential hypertension.Expert Opin Pharmacother. 2000 May;1(4):675-82.

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