A80-1-01 Blunted Brain Response to Respiratory Events Is Associated With Decreased Global Cognitive Function; The Multiethnic Study of Atherosclerosis

Abstract Rationale There is substantial variability in the electroencephalographic (EEG) response to apneas and hypopneas among individuals with obstructive sleep apnea (OSA). A previous cross-sectional clinical study has demonstrated that a blunted brain response to respiratory events is associated with cognitive impairment. In this study, we examined both cross-sectional and longitudinal associations between EEG responses to respiratory with cognition in a large, multiethnic, community-based cohort. Methods Participants in the multi-site Multi-Ethnic Study of Atherosclerosis (MESA) Sleep Study underwent in-home full polysomnography as part of the MESA Sleep ancillary (MESA Exam 5, n≈2200; 2010-2013). EEG responses to respiratory events were quantified using the power ratio, defined as the median absolute power after the event divided by the median absolute power preceding the event, calculated across EEG frequency bands (theta, alpha, and beta). An overall Brain Response to Event (BReTE) metric was computed by summing the averaged within-individual responses across all frequency bands and served as the primary exposure. Standardized cognitive assessments were performed at MESA Exam 5 and repeated at Exam 7 (n≈900; 2022-2024). The Global Cognitive Composite (GCC), a summary measure combining all available cognitive test scores, was the primary outcome. We employed multivariable linear regression models controlling for age, sex, race and ethnicity, body mass index, AHI, education, income, smoking status, respiratory events’ baseline EEG activity, medications known to influence cognition, and comorbidities. Cross-sectional analyses were conducted using data from Exam 5. For longitudinal analyses, we evaluated whether Exam 5 EEG response predicted cognitive scores at Exam 7, adjusting for Exam 5 cognitive performance. Results We studied data from 1,880 participants (53% female) with a median IQR age of 67 61,75 years, AHI of 18 9,32 event/h, and BReTE of 4.47 3.97,5.15. Cross-sectional analyses suggested that a lower level of BReTE was associated with poor cognitive performance. Longitudinal analyses also showed similar associations. Specifically, a one standard deviation reduction in BReTE at exam 5 was associated with a -0.05 -0.09, -0.01 SD decrease on exam 7 GCC scores (Table 1). As an exploratory analysis, similar results were found for all frequency bands’ power ratios. Conclusion Blunted OSA-related brain response is associated with reduced global cognitive function in aging adults. This association may reflect effects of accelerated brain aging or a higher arousal threshold from chronic exposure to OSA. Future prospective studies are needed to confirm these findings and explore the mechanisms underlying these associations. This abstract is funded by: NIH