Reena Mehra, MD: Hypoxia, a Consistent Driver of Atrial Fibrillation

In an interview with HCPLive, Reena Mehra, MD, MS, director, professor of medicine, at the Sleep Disorders Center, Cleveland Clinic, discussed the accumulation of data that led to multiple presentations at SLEEP 2023 in Indianapolis, IN.

Sleep apnea has a high magnitude of established associations with AF, and the development of new AF. There's also evidence indicating the apneas and hypopneas, are linked with discrete episodes of cardiac arrhythmias.

"In total, (these) data really support a causal relationship based upon the data that has accrued over the last several decades," Mehra said.

However, it is crucial to recognize that obstructive sleep apnea is often underdiagnosed, despite its high prevalence.

"It is highly prevalent, with nearly 1 billion people worldwide afflicted with sleep apnea, but it's estimated that about 85% of individuals with sleep apnea have not been diagnosed," she explained. "So, this is a problem because atrial fibrillation, in particular, is an epidemic–it will increase by fivefold by the year 2050 compared to where it is now."

The possibility that sleep apnea could be one of the unrecognized factors exacerbating the growing rates of AF emphasizes the necessity of awareness, screening, diagnosing, and treating sleep apnea, according to Mehra.

The latest investigation, led by Catherine Heinzinger, DO, evaluated the Cleveland Clinic's registries of approximately 170,000 sleep studies, to assess the relationship between sleep apnea and AF. The results showed an emphasis on the role of hypoxia, rather than any subtypes of sleep apnea.

"The percentage of time spent below a threshold of 90% oxygen saturation, (Heinzinger) found, was the strongest factor that was predictive of the development of atrial fibrillation, beyond the traditional metric that we use called the Apnea-Hypopnea Index (AHI)," she explained.