FAMILIAL HISTORY OF STROKE AND STROKE RISK - THE FAMILY HEART-STUDY

Background and Purpose Although familial history of stroke is generall y perceived to be an important marker of stroke risk, very few epidemi ological studies have been published to address this hypothesis. We so ught to examine whether familial history of stroke is associated with the prevalence of stroke in the Family Heart Study, a National Heart, Lung, and Blood Institute-supported multicenter study of the familial, genetic, and nongenetic determinants of cardiovascular disease in pop ulations. Methods The personal and familial histories of stroke were a ssessed in 3168 individuals (probands) who were at least 45 years old and 29 325 of their first-degree relatives with the use of a standardi zed questionnaire. Results The age-, ethnicity-, and sex-adjusted stro ke prevalences were 4.8%, 4.9%, and 3.9% in probands with a positive f amilial, paternal, and maternal history of stroke, respectively, in co mparison with 2.0% in probands without any positive familial history ( P<.01). The age-, ethnicity-, and sex-adjusted odds ratios (95% confid ence interval) of stroke were 2.00 (1.13, 3.54) for a positive paterna l and 1.41 (0.80, 2.50) for a positive maternal history of stroke. Add itional statistical adjustment for the proband's history of elevated c holesterol level, cigarette smoking status, history of coronary heart disease, hypertension, and diabetes did not alter the associations. A similar pattern was seen for African Americans and European Americans. Conclusions The increased risk of stroke among persons with a positiv e familial history of stroke compared with those without a familial hi story of stroke is consistent with the expression of genetic susceptib ility, a shared environment, or both in the etiology of stroke.