[Isolated systolic hypertension: a significant risk factor of cerebral apoplexy and acute myocardial infarction. A prospective population based study].

The aim of this prospective population based study was to determine the prevalence of isolated systolic hypertension (ISH) and associated cardiovascular risk. ISH was defined as systolic blood pressure > or = 160 mmHg and diastolic blood pressure < 90 mmHg. The associated risk of stroke and myocardial infarction (MI) was assessed using a multivariate Cox regression model. Subjects (n = 6621) were included if aged 50 or older, without antihypertensive or cardiac medicine, and without a previous stroke or MI. The prevalence of ISH increased from 3% among fifty-year olds to 13% among seventy-year olds. No sex difference was found. Adjusted relative risk of stroke was 3.0 (95% CI 1.6-5.3) for women and 2.7 (1.8-4.3) for men when compared to normotensives. Adjusted relative risk of MI was 0.8 (0.3-2.0) for women and 1.6 (1.0-2.5) for men. Population attributable risk percent for stroke associated with ISH is up to 30%.