Racial Differences in Risks for First Cardiovascular Events and Non-Cardiovascular Death: The Atherosclerosis Risk in Communities Study (ARIC), the Cardiovascular Health Study (CHS), and the Multi-Ethnic Study of Atherosclerosis (MESA)
Background—No studies have compared first CVD events and non-CVD death between races in a competing risks framework, which examines risks for numerous events simultaneously.
Methods and Results—We used competing Cox models to estimate hazards for first CVD events and non-CVD death within and between races in three multi-center, NHLBI-sponsored cohorts. Of 14569 ARIC study participants aged 45-64y with mean follow up of 10.5y, 11.6% had CVD and 5.0% had non-CVD death as first events; among 4237 CHS study participants aged 65-84y and followed for 8.5y, these figures were 43.2% and 15.7%, respectively. Middle-aged blacks were significantly more likely than whites to experience any CVD as a first event; this disparity disappeared by older adulthood and after adjustment for CVD risk factors. The pattern of results was similar for MESA participants. Traditional Cox and competing risks models yielded different results for CHD risk. Black men appeared somewhat more likely than white men to experience CHD using a standard Cox model (HR 1.06; 95% CI 0.90, 1.26) whereas they appeared less likely than white men to have a first CHD event using a competing risks model (HR 0.77; 95% CI 0.60, 1.00).
Conclusions—CVD affects blacks at an earlier age than whites; this may be partially attributable to elevated CVD risk factor levels among blacks. Racial disparities in first CVD incidence disappear by older adulthood. Competing risks analyses may yield somewhat different results than traditional Cox models and provide a complementary approach to examining risks for first CVD events.
- Received July 20, 2011.
- Accepted May 2, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited