Abstract 18787: Population-Based Data from Western Alaska Native People Show High Rates of CHD and Stroke Mortality: The WATCH Study

Abstract

Background: Early low rates of CVD among Western Alaska native people were attributed to consumption of omega-3 rich foods. Mortality data suggest that rates are rising, but no population-based data have been reported. Methods: The Western Alaska Tribal Collaborative for Health (WATCH) combines three ongoing population-based studies - EARTH, CANHR, and GOCADAN, as well as data from the ASP. The consolidated cohort, the largest study of Western Alaska Native people, consists of 4,569 men and women >18 yrs of age who underwent baseline exams between 2000 and 2010 and were followed an average of 6.7 years (<1% lost to follow-up). CHD, stroke, and all CVD mortality were reviewed and adjudicated using standardized criteria. CHD deaths included MI, definite sudden death due to CHD, and definite fatal CHD. Stroke included those with evidence of rapid fatal onset of localized neurologic deficit or imaging consistent with stroke. CVD included CHD, stroke, and other fatal CVD. Age-adjusted rates (to the 2000 US census) were compared with those of US Whites and Blacks. Results: The baseline cohort was 54% female (mean age 40y for men and 42y for women) (Table). After an average 6.7 years, there were a total of 48 CVD deaths, 30 from CHD, and 17 from stroke. In Western Alaska native people, CHD mortality was similar to that of US Whites, with mortality in men exceeding that in women, but somewhat lower than rates for US Blacks; stroke mortality was similar in men and women, exceeding rates in both US Whites and Blacks. Conclusions: These results demonstrate high rates of CVD mortality, especially for stroke, compared with US Whites and Blacks, suggesting increasing rates in Western Alaska native people. Longer follow up to increase sample sizes is needed to confirm this trend, and the role of risk factors in these changes needs investigation. However, even these limited data suggest that community-based CVD prevention is needed in these populations.