Impact of diet on mortality from stroke: results from the U.S. multiethnic cohort study.

OBJECTIVES: Stroke is the fourth leading cause of death in the United States and stroke mortality rates vary by ethnicity. The purpose of this study was to examine the associations between food group consumption and risk of death from stroke among 5 ethnic groups in the United States. METHODS: The Multiethnic Cohort includes >215,000 participants, the majority of whom are African American, Native Hawaiian, Japanese American, Latino, and Caucasian men and women recruited by mail survey in Hawaii and Los Angeles in 1993-1996. Deaths from stroke were identified by linkage to the state death files and the U.S. National Death Index. Diet was assessed using a validated food frequency questionnaire. Associations were examined using multivariable Cox proportional hazards models, stratified by ethnicity and gender. RESULTS: A total of 860 deaths from stroke were identified among the cohort participants. Vegetable intake was associated with a significant reduction in risk for fatal stroke among African American women (relative risk [RR]=0.60; 95% CI: 0.36-0.99). Among Japanese American women only, high fruit intake was significantly associated with a risk reduction for stroke mortality (RR=0.43; 95% confidence interval [CI]: 0.22-0.85), whereas meat intake increased risk (RR=2.36; 95% CI: 1.31-4.26). Among men, a significant reduction in stroke mortality was observed among Native Hawaiians (RR=0.26; 95% CI: 0.07-0.95). After pooling the data for the ethnic groups, the findings support an elevated risk for high meat intake among women overall (RR=1.56; 95% CI: 1.12-2.16); no significant effects of dietary intake on risk for fatal stroke were observed among men. CONCLUSIONS: Although some variations were observed for the associations between diet and stroke mortality among ethnic groups, the findings suggest that these differences are not substantial and may be due to dietary intake of specific food subgroups. Additional investigations including dietary subgroups and nutrients sources are needed to clarify these findings.