IS DIASTOLIC HYPERTENSION AN INDEPENDENT RISK FACTOR FOR STROKE IN THE PRESENCE OF NORMAL SYSTOLIC BLOOD-PRESSURE IN THE MIDDLE-AGED AND ELDERLY

In a prospective population-based study from the Copenhagen City Heart Study, the role of diastolic blood pressure as an independent risk fa ctor of stroke, in the presence of normal systolic blood pressure, was assessed in 6,545 subjects aged 50 to 80 years. Follow-up was 12 year s. Subjects were divided into various blood pressure categories accord ing to both diastolic and systolic blood pressure. The risk of stroke was assessed using a multivariate Cox proportional hazards model, taki ng into account various cardiovascular risk factors (age, sex, smoking , diabetes mellitus, body mass index, and levels of serum cholesterol) . After adjustment for risk factors, only subjects with elevated systo lic blood pressure had a significantly increased risk of future stroke . The risk of stroke according to blood pressure categories further re flected increasing levels of pulse pressure, with the highest risk of stroke in subjects with the greatest pulse pressure. We conclude that systolic blood pressure is a better predictor of stroke than is diasto lic blood pressure, and question whether diastolic blood pressure, in the presence of normal systolic blood pressure, is an independent risk factor for stroke in the middle-aged and elderly. (C) 1997 American J ournal of Hypertension, Ltd.