Community surveillance of stroke in persons under 70 years old: contribution of uncontrolled hypertension.

In 1979, a community-wide hospital surveillance system was established in Monroe County, New York (population 702,000), to investigate the continuing contribution of uncontrolled high blood pressure (HBP) to the occurrence of stroke. This paper reports findings among 200 consecutive strokes in persons under 71 years of age. Average age was 58. There was a prestroke history of HBP in 129 (65 per cent) cases. Two-thirds of the 129 had other predisposing conditions (heart disease, diabetes, previous cerebrovascular accident) and 95 per cent had one or more other cardiovascular risk factors (smoking, elevated cholesterol, obesity). Over 90 per cent had visited a physician during the year prior to stroke (average of four visits). Elevated pressures (DBP greater than or equal to 95 or SBP greater than or equal to 160) were recorded at half or more of the visits for 45 per cent of the patients; these cases were classified as uncontrolled. Reduction of "unnecessary" strokes in persons under age 71 should be achievable by giving increased attention to those already under medical care for hypertension who have co-existing stroke risk conditions and cardiovascular risk factors.