The Connection Between AFib and Sleep Apnea

August 04, 2023

Two health problems – atrial fibrillation (AFib) and obstructive sleep apnea – often go hand in hand. In fact, it’s estimated that half of people with AFib also have sleep apnea, according to the Heart Rhythm Society. The prevalence of both disorders is on the rise, likely due to increases in obesity and cardiovascular disease.

“The more untreated sleep apnea a person has, the more they likely have AFib,” says Shashank Jain, MD, a cardiac electrophysiologist with University Hospitals Harrington Heart & Vascular Institute. Diagnosing and treating both conditions is important because each elevates the risk of stroke and premature death.

Sleep Apnea and AFib: A Common Set of Risk Factors

AFib is an irregular heartbeat caused by faulty electrical signals that make the upper chambers of the heart (the atria) quiver instead of contracting properly. Obstructive sleep apnea happens when breathing starts and stops or becomes critically shallow during sleep.

“There is about a four times higher association between people with obstructive sleep apnea and AFib, and it seems to be independent of other factors,” says Dr. Jain.

The overlap between the conditions is not yet fully understood. The two disorders share common risk factors, including obesity, older age, heart failure, high blood pressure and heavy alcohol use. Dr. Jain said the clearest understanding is that interrupted breathing during sleep triggers changes in the heart.

“There are a lot of prevailing theories, but a big part of it is believed to be injury to the heart during sleep apnea, especially untreated sleep apnea. There may be microscopic injury to cardiovascular structures, including the atria (upper heart chambers), which allows AFib to occur.”

Evaluation for Sleep Apnea

Jessica Guggenbiller, CNP, a University Hospitals sleep medicine certified nurse practitioner, says some patients with AFib are referred by cardiology for evaluation for sleep apnea.

Evaluation involves a series of questions for patients and their partners about symptoms such as paused breathing, snoring, frequent awakening, daytime sleepiness and frequent heart palpitations.

“Patients may be referred for a sleep study, which involves monitoring breathing, heartbeat, blood oxygen levels, brain waves and other measures, depending on the type of study,” says Guggenbiller. “Some patients are sent home with portable monitors, while others spend a night at a sleep lab for more sophisticated testing.”

For sleep medicine patients who have not been diagnosed with AFib, a sleep study done in a lab may include an EKG (electrocardiogram), which would detect signs of AFib.

Does Sleep Apnea Treatment Improve AFib?

There is evidence that CPAP (continuous positive airway pressure) – the primary treatment for sleep apnea – may reduce recurrence of AFib. The connection is somewhat unclear, but the strongest evidence comes from studies where patients were treated for both AFib and sleep apnea, Dr. Jain says.

Patients who underwent catheter ablation procedures for AFib had less recurrence if they were also treated with CPAP. Ablation destroys small areas of heart tissue responsible for faulty electrical signals that cause irregular heartbeat.

“We know that people with untreated sleep apnea haver a higher risk of recurrence of AFib after ablations. We also think that in people treated with CPAP, there seems to be a reduction in their AFib recurrence,” Dr. Jain says.

Studies also suggest that untreated sleep apnea reduces the effectiveness of medications for AFib. “Treatment for sleep apnea can make the treatments for AFib work a little better,” Guggenbiller says.

While treatment for both disorders may by lifelong, lifestyle changes such as weight loss, diet and exercise can reduce severity. In the case of sleep apnea, weight loss can reduce the need for CPAP in some patients.