Atrial Fibrillation More Prevalent in US Than Previously Estimated: Daily Dose

Patient Care brings primary care clinicians a lot of medical news every day—it’s easy to miss an important study. The Daily Dose provides a concise summary of one of the website's leading stories you may not have seen.


On September 13, 2024, we reported on a study published in the Journal of the American College of Cardiology that examined the contemporary age-, sex-, and race-standardized prevalence and the number of adults with diagnosed atrial fibrillation (AF) in the US.

The study

Researchers used statewide health care databases in California to create a cohort of patients aged 20 years and older who received hospital-based care between 2005 and 2019, using International Classification of Diseases codes to identify patients with AF and comorbidities. Data from the US Census were used to calculate the prevalence of diagnosed AF.

The findings

Out of a total of 29 250 310 patients, AF was diagnosed in 2 003 867 for a prevalence of 6.8%. In 2005 to 2009, 4.49% of patients were diagnosed, with the proportion of affected individuals increasing to 6.82% in 2015 to 2019.

The researchers' overall estimate of the current national prevalence of AF is at least 10.55 million individuals (95% CI, 10.48-10.62 million). This translates to 4.48% of adults in the US (95% CI, 4.47%-4.49%). These estimates put the prevalence of AF 3 times higher than what was projected in the study using 1996 to 1997 data.

Authors' comment

"The 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."

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