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Rebecca Corey

This heart condition is 3 times more common than we thought, researchers say


Atrial fibrillation, an irregular heartbeat, is three times more common than previously thought, according to a new study published on Wednesday.


Estimates from more than two decades ago had projected that atrial fibrillation (or A-fib) affects 3.3 million adults in the U.S. But researchers at the University of California, San Francisco found that A-fib affects 10.5 million adults, or nearly 5% of the adult U.S. population.


What did the study say?

The researchers at UCSF reviewed the medical records of nearly 30 million adults who received “acute or procedural care” in California from 2005 to 2019, and found that about 2 million of those patients had been diagnosed with A-fib. The number of diagnoses increased over time — from nearly 4.5% of patients between 2005 and 2009 to 6.8% of patients between 2015 and 2019. The data was then standardized to be nationally representative, giving researchers a final estimate of at least 10.5 million A-fib cases nationwide.


A-fib is one of the most common causes of stroke and can lead to increased risk of heart failure, blood clots, chronic kidney disease and dementia.


Dr. Gregory Marcus, a senior author of the study and cardiologist at UCSF Health, tells Yahoo Life that researchers suspected A-fib was more common than previously estimated — “but we were surprised by the large magnitude of the actual difference observed” in the study.


“These data also help to provide some comfort to the millions of patients contending with the disease, so they know they are not alone,” he says.


Marcus hopes the study’s findings will lead to more allocation of resources to help A-fib patients, including more funding for research and treatment. “For example, there is now strong evidence that physical activity can reduce the burden of this disease, and yet Medicare does not cover cardiac rehabilitation programs for atrial fibrillation,” he says.


What’s behind the increase in A-fib numbers?

Experts say the increase is likely due to a combination of more cases and enhanced detection of the disease.


  • There’s an uptick in known risk factors. “The longer people live with many chronic conditions, such as high blood pressure, diabetes, metabolic syndrome, obesity, sleep apnea and other medical problems, the more likely they are to develop A-fib,” Dr. Paul Wang, director of the Stanford Cardiac Arrhythmia Service, tells Yahoo Life. Dr. Rod Passman, director of the Center for Arrhythmia Research at Northwestern University, adds that obesity — which is also on the rise in the U.S. — is often responsible for A-fib cases in younger patients.

  • Detection methods are improving. Not only are medical-grade monitors picking up more instances of A-fib, but consumer wearables like Apple Watches and Fitbits are bringing more cases to clinicians’ attention. “Barely a week goes by in my office where someone doesn’t come in and say, ‘My Apple Watch told me I had atrial fibrillation and I didn’t feel anything,’” Passman tells Yahoo Life. But don’t just rely on a diagnosis from your smartwatch; Passman notes that it’s important to visit a doctor and get confirmation.

  • Everyone is aging. “A-fib is known to increase with age,” Wang says. “As the population ages, A-fib is expected to increase.”


How can you reduce your risk of developing A-fib?

Healthy habits can decrease your chances of an A-fib diagnosis.


  • Keep chronic conditions under control. Wang says that managing chronic conditions that are associated with developing A-fib may help. “For example, treating diabetes and hypertension may reduce A-fib,” he says. Dr. Frederick Ehlert, a cardiac electrophysiologist and associate professor of medicine at Columbia University, tells Yahoo Life that patients should control their blood pressure with medication, if necessary, and monitor blood glucose levels.

  • Make good lifestyle choices. Passman and Ehlert recommend staying in shape and maintaining a healthy weight — “physical activity is key,” Passman says — along with getting a good night’s sleep, reducing stress and staying hydrated.

  • Cut back on drinking and smoking. “Moderate or even eliminate substances that can trigger atrial fibrillation, especially alcohol, caffeine and nicotine,” Ehlert says. This is especially true for people who have A-fib and notice that it triggers their symptoms, he adds.


However, as Ehlert points out, “sometimes you can do everything possible and still get atrial fibrillation.”


What should you do if you have it?

While wearable tech like an Apple Watch or a Fitbit might pick up signs of A-fib, it’s formally diagnosed by a clinician using tests like an electrocardiogram (or EKG), which measures the electrical activity of the heart.


Early detection and treatment is important as it can reduce the risk of serious outcomes, such as stroke and blood clots.


“There are now many evidence-based effective treatments for the disease, such as catheter ablation, and well-tolerated medicines to help avoid the [worst] consequences,” Marcus says.

Ehlert adds that while A-fib is “rarely an immediately life-threatening condition,” if you feel your heart “racing” or experience shortness of breath or lightheadedness, it’s best to seek medical attention for help with treating those symptoms.


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