Moderate-to-Severe OSA Tied to Doubled Risk of Brain Microbleeds: Daily Dose

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On November 6, 2025, we reported on a study published in JAMA Network Open that was designed to examine the association between obstructive sleep apnea (OSA) severity and risk of incident cerebral microbleeds (CMBs) in middle-aged and older adults.

The study

Researchers drew participants from the Korean Genome and Epidemiology Study (KoGES), an ongoing longitudinal investigation. Between 2011 and 2014, participants underwent baseline in-home polysomnography and brain MRI, with follow-up assessments at 4-year intervals through 2022. The prospective cohort study included 1441 adults.

OSA severity was categorized by apnea-hypopnea index (AHI) as: no OSA (0-4.9 events/hour), mild OSA (5.0-14.9 events/hour), and moderate to severe OSA (15.0 or more events/hour). The study excluded participants with baseline microbleeds, history of cerebrovascular or cardiovascular disease, or missing covariates.

The findings

The cumulative incidence of CMBs was:

• At 4 years: 1.85% (no OSA), 1.61% (mild), 4.66% (moderate-to-severe)

• At 8 years: 3.33% (no OSA), 3.21% (mild), 7.25% (moderate-to-severe)

In multivariable models that adjusted for demographics, cardiovascular risk factors, white matter changes, and longitudinal changes in AHI and BMI, only the 8-year risk for moderate to severe OSA remained significantly elevated.

Authors' comments

"In this study, moderate to severe OSA was independently associated with an increased risk of incident CMBs over an 8-year follow-up. These results add to the evidence for the importance of sleep apnea to brain health."

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