Total Homocyst(e)ine Concentration and the Likelihood of Nonfatal Stroke

Abstract

Background and Purpose —Elevated serum total homocyst(e)ine [H(e)] is an independent risk factor for stroke. Few studies, however, have examined this association in blacks. Methods —Data from the Third National Health and Nutrition Examination Survey (n=4534), a nationally representative sample of US adults, were used to examine the relationship between H(e) and a physician diagnosis of stroke (n=185) in both black and white adults. Multivariate-adjusted logistic regression analyses were used to examine this relationship. Results —Serum vitamin B 12 and folate concentrations were significantly lower among participants in the highest H(e) quartile (≥12.1 μmol/L) than among participants in the lowest quartile (≤7.4 μmol/L). Those in the highest quartile were older, had higher mean cholesterol and blood pressure levels, and were more likely to smoke and to have completed <12 years of education. After adjustment for age, the odds ratio (OR) for stroke was 2.9 (95% confidence interval [CI], 1.4 to 5.7; highest versus lowest quartile). Adjustment for gender, race/ethnicity, education, systolic blood pressure, cholesterol, diabetes mellitus, and smoking reduced the magnitude of the association (OR, 2.3; 95% CI, 1.2 to 4.6). The association between H(e) and stroke did not differ by race [ P =0.265 for race-H(e) interaction term]. The multivariate adjusted OR for the highest quartile versus the lowest was 2.5 (1.1 to 5.5) among whites and 1.4 (0.4 to 4.7) among blacks. Conclusions —In this nationally representative sample of US adults, H(e) concentration was independently associated with an increased likelihood of nonfatal stroke. This association was present in both black and white adults.