Atrial fibrillation is estimated to be three times more common than previously thought

Atrial fibrillation, a fast, irregular heartbeat that can lead to stroke or sudden death, is three times more common than previously thought and affects nearly 5% of the population, or 10.5 million U.S. adults, according to new estimates from UC San Francisco.

A-Fib, as the condition is commonly known, has been on the rise over the past decade, driven by an aging population and rising rates of hypertension, diabetes and obesity. Previous projections had estimated that 3.3 million American adults had atrial fibrillation, but these have not been updated in more than two decades.

The study will be published on September 11 JACC.

“Atrial fibrillation doubles the risk of mortality, is one of the most common causes of stroke, increases the risk of heart failure, myocardial infarction, chronic kidney disease and dementia, and results in a lower quality of life,” said first author Jean Jacques Noubiap. M.D., Ph.D., a postdoctoral fellow at UCSF with a specialty in global cardiovascular health.

“Fortunately, atrial fibrillation is preventable and early detection and appropriate treatment can significantly reduce its adverse effects,” he said.

The rising numbers reflect the need for better prevention and treatment

UCSF researchers reviewed the medical records of nearly 30 million adult patients who received some form of acute or procedural care in California from 2005 to 2019. About 2 million of these people had been diagnosed with A-Fib, and this number grew over time, rising from 4.49% of patients treated between 2005 and 2009 to 6.82% of patients treated between 2015 and 2019.

The data was standardized to reflect the entire country, and researchers estimate the current national prevalence to be at least 10.55 million. They also found that during the study period, A-Fib patients were younger, less likely to be female, and more likely to have hypertension and diabetes.

A-Fib has a wide spectrum of complications, from shortness of breath and light-headedness to blood clots, strokes and even heart failure. Studies have shown that people with A-Fib are up to five times more likely to have a stroke. The authors say that by outlining the scope of the problem, these new estimates can help guide health care planning, resource allocation and public health interventions.

“Physicians recognize that atrial fibrillation is common in virtually every field,” says senior and corresponding author Gregory M. Marcus, MD, MAS, a cardiologist and electrophysiologist at UCSF Health. “These data provide objective evidence showing that previous projections have seriously underestimated how often it actually occurs.”

Digital technologies may reveal that this is even more common than current analysis suggests.

“With the growing use of consumer wearables designed to detect atrial fibrillation, combined with safer and more effective means to treat it, this current prevalence of atrial fibrillation in healthcare may soon be dwarfed by future healthcare utilization that will occur as a result of the disease. Marcus said.

The other authors are Janet J. Tang, Ph.D., MPH; Justin T. Teraoka; and Thomas A. Dewland, MD, all Departments of Cardiology at UCSF.