Isolated systolic hypertension--epidemiology and impact in clinical practice.
OBJECTIVE
To study the frequency, distribution and determinants of isolated systolic hypertension (ISH).


METHODS
Cross-sectional study, in two stages. First, consecutive patients of the Portuguese national health system aged 60 or over were selected (1999). The second stage covered people aged up to 60 years (2000).


METHODS
Health Centers--primary care (Regional Health Administration--Lisbon).


METHODS
3228 patients, 1100 male (439 aged up to 60 years and 661 aged > or = 60 years) and 2128 female (860 aged up to 60 years and 1268 aged > or = 60 years).


METHODS
Categories of hypertension. Risk stratification. Cardiovascular morbidity. Predictors of isolated systolic hypertension.


RESULTS
The definition and staging of hypertension changed between 1988 and 1997/99 and as a consequence, there has been, in hypertensives, an increase in ISH frequency from 13% to 44% (2.4 times greater). This form of hypertension is far more frequent than grades 1 (mild hypertension = 22%), 2 (moderate hypertension = 15%) or 3 (severe hypertension = 7%). The proportion of hypertensives with ISH increases from 19% in people aged up to 40, to 30% in the fourth decade, 34% in the fifth decade, 44% in the sixth decade, 51% in the seventh decade, and 57% in those over 80 years of age. In hypertensives aged up to 50, ISH is more frequent in females. However, in those over age 50 it is predominant in males. ISH represents 60% and 37% respectively of untreated and treated hypertensives. Among untreated hypertensives, age was associated with ISH (p < 0.001; OR = 1.051 and 95% CI 1.037-1.065). In the over-60 subgroup, the following factors were associated: age (p = 0.013; OR = 1.048 and 95% CI 1.010-1.087); gender--male (p = 0.004; OR = 2.578 and 95% CI 1.361-4.881) and height (p = 0.044; OR = 0.966 and 95% CI 0.933-0.999).


CONCLUSIONS
Isolated systolic hypertension is the most common form of hypertension and the most often untreated. The constitutional characteristics associated with isolated systolic hypertension in the elderly are age, gender (male) and body mass index (height). The extent of the problem justifies more attention to control of systolic blood pressure, both in research (efficacy) and in clinical practice (effectiveness).
Rocha
Evangelista
E
Instituto de Medicina Preventiva e Departamento de Biomatemática da Faculdade de Medicina de Lisboa. evangelistarocha@hotmail.com
Mello e Silva
Alberto
A
Gouveia-Oliveira
A
A
Nogueira
Paulo
P
D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D017678:Sex Distribution; D012737:Sex Factors