Blood pressure predicts stroke risk for all groups

NEW YORK (Reuters Health) - Systolic blood pressure is an important predictor of stroke risk among men and women and across racial groups, according to a report in the American Journal of Hypertension.

Systolic blood pressure -- the top reading of the blood pressure -- has been shown to be a better predictor of stroke than diastolic blood pressure - the lower reading -- among apparently healthy white men, the authors explain, but it is unclear whether this holds true for women and African Americans.

Dr. David W. Brown and colleagues from the Centers for Disease Control and Prevention in Atlanta, investigated whether various blood pressure parameters -- individually and in combination -- improved the prediction of stroke events, using data from the Second National Health and Nutrition Examination Survey (NHANES II) Mortality Study.

The study population included 3295 men and 3462 women. Over a median follow-up of nearly 15 years, 113 fatal strokes occurred.

Brown's team found that increasing systolic blood pressure, diastolic blood pressure, pulse pressure, and mean arterial pressure were individually associated with an increased risk of fatal stroke.

Adding any other parameter to systolic blood pressure did not improve its ability to predict stroke, the results indicate. Specifically, for every 10 mm Hg increase in systolic blood pressure, the relative risk of stroke was 1.19 for men, 1.15 for women, 1.17 for whites, and 1.28 for African Americans.

These results "agree with those from previous studies and show that systolic blood pressure is an important risk predictor for fatal stroke...and provide further evidence of the need to control systolic blood pressure in the population," the investigators conclude.

SOURCE: American Journal of Hypertension, March 2007.