Brain HealthSleep Apnea Linked to Poorer Memory and Higher Dementia Risk in Middle Age
A cross-sectional study of 2,795 cognitively unimpaired Australians aged 40–70 found that those with self-reported obstructive sleep apnea (OSA) scored significantly worse on memory tests and had higher CAIDE dementia risk scores than those without OSA. The memory deficit was attenuated after adjusting for vascular risk factors like obesity, hypertension, and high cholesterol, suggesting OSA's cognitive impact is partly mediated through cardiovascular pathways. Notably, carrying the APOE ε4 allele — the strongest genetic risk factor for Alzheimer's — did not worsen or modify the OSA-cognition relationship. The findings support routine OSA screening in midlife as a practical tool for identifying individuals at elevated dementia risk before symptoms emerge.
