Baseline* (1987–89) characteristics of Atherosclerosis Risk in Communities participants enrolled in Medicare fee-for-service, overall and by source of incident atrial fibrillation diagnosis.

*Baseline age is age upon meeting enrollment criteria for the present analysis. All other characteristics are from the initial ARIC study exam (1987–1989).ARIC = Atherosclerosis Risk in Communities.CMS = Centers for Medicare and Medicaid Services.Continuous variables presented as mean ± standard deviation (SD).P-values from testing the null hypothesis of independence from chi-square (categorical) and F-test (continuous).