Minimum National Prevalence of Diagnosed Atrial Fibrillation Inferred From California Acute Care Facilities

Abstract

BackgroundPrevalence estimates of atrial fibrillation (AF) from large populations have not been updated for >2 decades. Using data from 1996 to 1997, a previous study projected that there would be 3.3 million adults with AF in the United States in 2020. ObjectivesThe purpose of this study was to determine the contemporary age-, sex-, and race-standardized prevalence and the number of adults with diagnosed AF in the United States. MethodsWe merged California’s state-wide health care databases to assemble a cohort of adults aged ≥20 years who received hospital-based care in California from 2005 to 2019. International Classification of Diseases codes were used to identify AF and other comorbidities. After accounting for deaths, we utilized the U.S. Census to calculate the national age-, sex-, and race-standardized estimates of diagnosed AF. ResultsOf 29,250,310 patients (mean age 50.6 ± 19.8 years, 53.8% women, 50.1% White), 2,003,867 (6.8%) had an AF diagnosis. The proportion of patients with diagnosed AF increased from 4.49% in 2005 to 2009 to 6.82% in 2015 to 2019. Over time, AF patients became relatively younger, were less likely to be female or White, and were more likely to have hypertension and diabetes. Standardizing based on age-, sex-, race-, and ethnicity-based proportions to the U.S. population, we estimate that the current national prevalence of diagnosed AF is at least 10.55 million (95% CI: 10.48-10.62 million), comprising 4.48% (95% CI: 4.47%-4.49%) of the adult population. ConclusionsThe prevalence of diagnosed AF in the United States is higher than previously estimated. More efficient prevention and treatment strategies are needed to curb the burden of AF in the United States.