An increasing number of studies have highlighted the association between obstructive sleep apnea (OSA) and cognitive dysfunction.¹ Proposed mechanisms include intermittent hypoxia, excessive daytime sleepiness, and sleep fragmentation, leading to cardiovascular and metabolic injury which may increase Alzheimer's disease neuropathology and impair sleep-supported cognitive processes.¹ Despite the established links between OSA and cognitive impairment, there remains a knowledge gap in understanding this relationship at a national population level.¹ During the AAN (AAN) 2024 Annual Meeting, Dr. Dominique Low from the Boston Medical Center, United States (US), presented the findings from a cross-sectional study that investigated the relationship between sleep apnea symptoms and cognitive symptoms in adults.¹

In this study, data from the 2017-2018 National Health and Nutrition Examination Survey, a nationally representative sample of US civilian, non-institutionalized adults, were analyzed.¹ Participants who reported snorting, gasping, or breathing pauses during sleep were categorized as experiencing sleep apnea symptoms, while those who reported memory problems, confusion, concentration problems, or decision-making difficulties were classified as having memory or cognitive symptoms.¹

In total, 4,257 adults ranging from 20 to ≥80 years completed the questionnaire, of which 24.9% had sleep apnea symptoms and 21.5% had cognitive problems.¹ Memory or cognitive problems were more frequently reported among those with sleep apnea symptoms compared to those without (30.1% vs. 18.7%), indicating a pronounced association between sleep apnea and these symptoms (odds ratio [OR]=1.88; 95% CI: 1.48-2.37; p<0.001).¹ This association remained significant even after adjusting for age, gender, race, and education (adjusted OR=2.02; 95% CI: 1.58-2.59; p<0.001).¹ The findings of this study, whose study population was a nationally representative sample of community-dwelling adults in the US, were consistent with prior research suggesting associations between untreated OSA and executive dysfunction in middle-aged men, as well as sleep-disordered breathing and increased risk of developing cognitive impairment in older women.¹

In summary, in this nationally representative survey of US adults, individuals who reported experiencing symptoms of sleep apnea, such as snorting, gasping or breathing pauses during sleep, were more likely to also report having memory, confusion, concentration, or decision-making difficulties compared to those without sleep apnea symptoms.¹ This observed association between sleep apnea symptoms and cognitive problems remained statistically significant even after accounting for factors like age, gender, race and education level.¹

While these cross-sectional findings suggest a link between sleep-disordered breathing and cognitive impairment in the general US population, further research is needed to better understand this relationship over time and with more detailed clinical assessments.¹ Longitudinal studies examining the national prevalence and trajectory of this issue could provide important insights into the potential cognitive consequences of untreated sleep apnea.¹