GUEST EDITORIAL

The scope of hypertension

RENATA CIFKOVA1 & KALINA KAWECKA-JASZCZ2

1Department of Preventive Cardiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic, and2Department of Cardiology I, Institute of Cardiology, College of Medicine, Jagiellonian University, Krakow, Poland

Hypertension is the most prevalent cardiovascular

disorder affecting 20–50% of the adult population in

developed countries (1). Whenever we compare the

prevalence of hypertension, we should be aware

that this is heavily dependent on the definition of

hypertension, population examined, number of

blood pressure readings taken on each occasion

and, finally, on the number of visits.

A recent comparative analysis of hypertension

prevalence and blood pressure levels in six European

countries, Canada and the USA, based on the

second blood pressure reading, showed a 60%

higher prevalence of hypertension in Europe com-

pared with the USA and Canada in population

samples aged 35–64 years (2). There were also

differences in the prevalence of hypertension among

European countries, with the highest prevalence in

Germany (55%), followed by Finland (49%), Spain

(47%), England (42%), Sweden (38%) and Italy

(38%). Prevalences in the USA and Canada were

half of the rates in Germany (28% and 27%,

respectively).

Findings from the WHO MONItoring trends

and determinants in CArdiovascular diseases

(MONICA) Project showed a remarkably higher

prevalence of hypertension in Eastern Europe, and

virtually no difference in the rates of controlled

hypertension among Eastern and Western popula-

tions (3).

Hypertension is a well-established risk factor for

the development of all clinical manifestations

of atherosclerosis. Elevated blood pressure is a

common and powerful predisposing factor for the

development of coronary heart disease, stroke,

peripheral arterial disease and heart failure (4).

Randomized clinical trials of blood pressure low-

ering using different drugs have convincingly shown

that the risks associated with rising blood pressure

can be substantially reduced, particularly for stroke

but, also, for coronary heart disease and heart

failure.

The impact of hypertension on the incidence of

cardiovascular disease in the general population is

best evaluated from the population-attributable risk.

The statistics take into account both the prevalence

of the risk factor (hypertension) and the strength of

its impact (risk ratio) on cardiovascular disease.

Because of the high prevalence of hypertension in

the general population and its risk ratio, approxi-

mately 35% of atherosclerotic events are attributable

to hypertension. The odds ratio or the relative risk to

the individual increases with the severity of hyper-

tension, but the attributable risk is greatest for mild

hypertension because of its greater prevalence in the

general population. Therefore, the burden of cardi-

ovascular disease that arises from hypertension in the

general population comes from those with relatively

mild blood pressure elevation (5). About half of the

cardiovascular events in the general population

occur at blood pressure levels below those recom-

mended for treatment with antihypertensive

medications. This indicates a need for vigorous

non-pharmacological treatment of persons with

high-normal blood pressure and for initiating drug

treatment in the vast majority of patients with mild

hypertension based on their total cardiovascular risk.

The 2003 European Society of Hypertension–

European Society of Cardiology Guidelines for the

Correspondence: Renata Cıfkova, Department of Preventive Cardiology, Institute for Clinical and Experimental Medicine, Vıde ska 1958/9, 140 21 Prague 4,

Czech Republic. Tel: +420-2-617-11-399. Fax: +420-2-617-10-666. E-mail: recf@medicon.cz

Blood Pressure. 2005; 14 (Suppl 2): 3–5

ISSN 0803-7051 print/ISSN 1651-1999 online # 2005 Taylor & Francis

DOI: 10.1080/08038020500429672

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management of arterial hypertension (6) suggest to

initiate drug treatment in patients with high-normal

blood pressure and high total cardiovascular risk

(post-stroke, coronary heart disease and diabetic

patients).

Only few countries have data on trends in the

prevalence of hypertension in the general popula-

tion. The National Health and Examination Survey

(NHANES) suggests that the prevalence of hyper-

tension in the USA has declined progressively

since 1972 and that blood pressure distribution has

shifted downward between 1960 and 1988 (7,8).

Unfortunately, the most recent report (9) shows an

increase in the prevalence of hypertension in the US

population. The increased prevalence of hyperten-

sion in the USA between 1988 and 1991 and 1999–

2000 appears to be partially related, but not solely

due to the increase in body mass index.

Finnish population data also show a decrease in

the prevalence of hypertension in 1992–1997 (10).

Five independent cross-sectional population surveys

conducted in the Czech Republic in 1985, 1988,

1992, 1997/98 and 2000/01 showed a significant

decrease in the prevalence of hypertension (11). The

prevalence of hypertension appears to diminish also

in Poland. The recent NATPOL project has shown

that current prevalence of hypertension, diagnosed

on basis of three separate visits, is 29% with

treatment efficacy of 12.5% (12).

Hypertension is poorly controlled worldwide (1),

with less than 25% controlled in developed coun-

tries, and less than 10% in developing countries.

Hypertension control rates also vary within countries

by age, gender, race/ethnicity, socio-economic

status, education and quality of healthcare (13).

Awareness of hypertension has improved in the USA

and other Western countries over the past decade,

but remains inadequate as only a proportion of those

who are aware of their diagnosis are treated, and an

even smaller number of those receiving treatment are

treated adequately. Sadly, however, the most impor-

tant parameter that is likely to have an impact on

public health is neither the number who are aware of

their hypertension nor the number taking steps to

improve it but, rather, the percentage whose blood

pressure is under control (14).

Hypertension can be prevented by complementary

application of strategies targeting the general popu-

lation and individuals at higher risk of developing

hypertension. Lifestyle interventions are more likely

to be successful, and the absolute reductions in risk

of hypertension are likely to be greater when

targeting the elderly and individuals at high risk of

developing hypertension. However, preventive

measures applied early in life provide the greatest

long-term potential for reducing the overall burden

of blood pressure-related complications in the

community (15).

A population-based approach aimed at achieving a

downward shift in the distribution of blood pressure

in the general population is an important component

for any comprehensive plan to prevent hypertension.

A small decrement in the distribution of systolic

blood pressure is likely to reduce the burden of

blood pressure-related illness (16).

An analysis based on the Framingham Heart

Study reported that a 2-mmHg reduction in diastolic

blood pressure in a white cohort aged 35–64 years

would result in a 17% decrease in the prevalence of

hypertension, a 14% reduction in the risk of stroke

and transient ischaemic attacks and a 6% reduction

in the risk of coronary heart disease (17).

The current recommendations for primary pre-

vention of hypertension involve a population-based

approach and an intensive targeted strategy focused

on individuals at high risk of hypertension. These

two strategies are complementary and emphasize six

approaches with proven efficacy for prevention of

hypertension: engage in moderate physical activity,

maintain normal body weight, limit alcohol con-

sumption, reduce sodium intake, maintain adequate

intake of potassium, and consume a diet rich in

fruits, vegetables and low-fat diary products, and

reduced saturated and total fat. Applying these

approaches to the general population as a compo-

nent of public health and clinical practice can help

prevent blood pressure from increasing, and can

help decrease elevated blood pressure levels in

individuals in high-normal blood pressure or hyper-

tension.

References

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Worldwide prevalence of hypertension: A systematic review. J

Hypertens. 2004;22:11–19.

2. Wolf-Maier K, Cooper RS, Banegas JR, Giampaoli S,

Hense H-W, Joffres M, et al. Hypertension prevalence and

blood pressure levels in 6 European countries, Canada and

the United States. JAMA. 2003;289:2363–2369.

3. Strasser T. Hypertension: The East European experience. Am

J Hypertens. 1998;11:756–758.

4. Kannel WB. Blood pressure as a cardiovascular risk factor:

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5. Kannel WB. Update on hypertension as a cardiovascular risk

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