Differences in the incidence of congestive heart failure by ethnicity: The multi-ethnic study of atherosclerosis

Background: The relationship between incident congestive heart failure (CHF) and ethnicity as well as racial/ ethnic differences in the mechanisms leading to CHF have not been demonstrated in a multiracial, population-based study. Our objective was to evaluate the relationship between race/ethnicity and incident CHF. Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) is a cohort study of 6814 participants of 4 ethnicities: white (38.5%), African American (27.8%), Hispanic (21.9%), and Chinese American (11.8%). Participants with a history of cardiovascular disease at baseline were excluded. Cox proportional hazards models were used for data analysis. Results: During a median follow-up of 4.0 years, 79 participants developed CHF (incidence rate: 3.1 per 1000 person-years). African Americans had the highest incidence rate of CHF, followed by Hispanic, white, and Chinese American participants (incidence rates: 4.6, 3.5, 2.4, and 1.0 per 1000 person-years, respectively). Although risk of developing CHF was higher among African American compared with white participants (hazard ratio, 1.8; 95% confidence interval, 1.1-3.1), adding hypertension and/or diabetes mellitus to models including ethnicity eliminated statistical ethnic differences in incident CHF. Moreover, African Americans had the highest proportion of incident CHF not preceded by clinical myocardial infarction (75%) compared with other ethnic groups (P=.06). Conclusions: The higher risk of incident CHF among African Americans was related to differences in the prevalence of hypertension and diabetes mellitus as well as socioeconomic status. The mechanisms of CHF also differed by ethnicity; interim myocardial infarction had the least influence among African Americans, and left ventricular mass increase had the greatest effect among Hispanic and white participants.