Scientific Reports · Jan 9, 2025

The impact of brain-systemic oxygenation coupling in sleep-disordered breathing on cognitive function in elderly

By Kawai M, Hosseini SMH, Buck C et al.

BACKGROUND: Intermittent hypoxia, a consequence of sleep-disordered breathing (SDB), may contribute to an increased risk of cognitive decline. However, the association between SDB and cognition remains highly variable. METHODS: Fifty-two community-dwelling healthy older adults (28 women) were recruited. All participants underwent neuropsychiatric evaluations, simultaneous ambulatory polysomnography (PSG), and near-infrared spectroscopy (NIRS) recordings. We quantified the average coherence between oxy-Hb and SpO₂ signals during SDB events to determine whether it could predict cognitive outcomes in healthy older adults, where higher coherence indicates reduced protection against systemic hypoxia. RESULTS: The mean (SD) coherence of oxy-Hb and SpO₂ was 0.16 (0.07). Linear regression analysis showed a significant association between mean coherence and worse Stroop Color Word Test scores (t=-0.304, p = .004). In contrast, oxy-Hb reduction alone and conventional SDB parameters did not show a significant association with cognition. CONCLUSION: This is the first report to demonstrate an association between a novel parameter of brain-systemic oxygenation coherence in SDB and cognition in older adults. A higher coherence rate of cortical oxy-Hb and systemic SpO₂ during SDB may reflect a loss of compensatory mechanisms against systemic hypoxia and could help stratify older adults with a higher risk for cognitive decline.

doi.org/10.1038/s41598-024-84305-3Open accessPubMed 39789019Biomarkers