Prediction of Atrial Fibrillation in a Racially Diverse Cohort: The Multi-Ethnic Study of Atherosclerosis (MESA)

Background-Existing equations for prediction of atrial fibrillation (AF) have been developed and validated in white and African-American populations. Whether these models adequately predict AF in more racially and ethnically diverse populations is unknown. Methods and Results-We studied 6663 men and women 45 to 84 years of age without AF at baseline (2000-2002) enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA). Of these, 38% were non-Hispanic whites, 28% non-Hispanic African Americans, 22% Hispanics, and 12% Chinese Americans. AF during follow-up was ascertained from hospitalization discharge codes through 2012. Information collected at baseline was used to calculate predicted 5-year risk of AF using the previously published simple CHARGE-AF model, which only includes clinical variables, and a biomarker-enriched CHARGE-AF model, which also considers levels of circulating N-terminal of the prohormone B-type natriuretic peptide and C-reactive protein. For comparison purposes, we also assessed performance of the 10-year Framingham AF model. During a mean follow-up of 10.2 years, 351 cases of AF were identified. The C-statistic of the CHARGE-AF models were 0.779 (95% CI, 0.744-0.814) for the simple model and 0.825 (95% CI, 0.791-0.860) for the biomarker-enriched model. Calibration was adequate in the biomarker-enriched model (chi(2)=7.9; P=0.55), but suboptimal in the simple model (chi(2)=25.6; P=0.002). In contrast, the 10-year Framingham score had a C-statistic (95% CI) of 0.746 (0.720-0.771) and showed poor calibration (chi(2)=57.4; P<0.0001). Conclusion-The CHARGE-AF risk models adequately predicted 5-year AF risk in a large multiethnic cohort. These models could be useful to select high-risk individuals for AF screening programs or for primary prevention trials in diverse populations.