Overview

• A study published in Neurology finds that oxygen drops during REM sleep in obstructive sleep apnea (OSA) are linked to small vessel brain damage and memory-region degeneration.
• Researchers observed increased white matter hyperintensities, markers of small vessel disease, in individuals with REM-specific hypoxemia.
• Structural brain changes included hippocampal shrinkage and entorhinal cortex thinning, both critical for memory consolidation.
• Sleep-dependent memory deficits were associated with reduced entorhinal cortex thickness, suggesting functional consequences of the observed brain damage.
• While the study establishes a strong association, causality remains unproven, and results may not generalize due to the predominantly white and Asian study sample.