Bone mineral density and stroke.

BACKGROUND AND PURPOSE We sought to assess the long-term predictive usefulness of bone mineral density (BMD) for stroke incidence and stroke mortality. METHODS The First National Health and Nutrition Examination Survey data were obtained from a nationally representative sample of noninstitutionalized civilians. A cohort of 3402 white and black subjects 45 through 74 years of age at baseline (1971 to 1975) was observed through 1992. Hospital records and death certificates were used to identify a total of 416 new stroke cases. RESULTS Results were evaluated to determine the relative risk (RR) for stroke per 1-SD decrease in BMD, after controlling for age at baseline, smoking status, alcohol consumption, history of diabetes, history of heart disease, education, body mass index, recreational physical activity, and blood pressure medication. In Cox proportional-hazards analyses, incidence of stroke was not associated with a decrease in BMD in any of the 3 race-sex groups: white men (RR, 1.01; 95% CI, 0.86 to 1.19; P=0.88), white women (RR, 1.13; 95% CI, 0.93 to 1.38; P=0.21), or blacks (RR, 0.93; 95% CI, 0.72 to 1.21; P=0.60). No association between BMD and stroke mortality was found (RR, 1.03; 95% CI, 0.86 to 1.23; P=0.77). CONCLUSIONS In a large national study, no significant associations of BMD and stroke incidence or mortality were found for whites or blacks.