Researchers Uncover Why Some People Face Greater Brain Damage From Poor Sleep - Video

Think losing sleep only makes you tired? Your genes might remember it for years.

Poor sleep may accelerate brain changes linked to Alzheimer's disease in people carrying specific genetic variants, according to a new study published in Alzheimer's & Dementia. Researchers from Edith Cowan University (ECU) found that the interaction between sleep habits and variations in the aquaporin-4 (AQP4) gene may influence brain health years before symptoms of dementia appear.

The AQP4 gene helps regulate fluid movement in the brain and supports the brain's natural waste-clearing system, which becomes most active during sleep. This system helps remove harmful proteins, including those associated with Alzheimer's disease.

The researchers examined 13 common AQP4 gene variants, along with participants' self-reported sleep habits, brain MRI scans, and cognitive test results.

They found that people carrying certain AQP4 variants experienced faster loss of grey matter when they reported shorter sleep duration. Grey matter contains many of the brain cells responsible for memory, learning, decision-making, and movement. Reduced grey matter volume is considered an early sign of structural brain changes.

In some participants, taking longer to fall asleep was also associated with lower brain volume. Cognitive performance changed differently depending on both sleep quality and the specific AQP4 variant an individual carried. Some gene variants appeared to make poor sleep more harmful, while others showed different patterns of brain and cognitive change.

The findings suggest that genetics may influence how strongly poor sleep affects the brain, meaning two people with similar Alzheimer's risk could respond differently to the same sleep habits.

The researchers emphasize that the results do not support routine genetic testing at this stage. Instead, they highlight the need for larger studies to confirm the findings and determine whether improving sleep can reduce genetically driven Alzheimer's risk. If confirmed, the research could pave the way for personalized Alzheimer's prevention.

REFERENCE: Tenielle Porter, Ayeisha Milligan Armstrong, et al.; Evidence for direct and sleep‐moderated relationships between aquaporin‐4 genetic variants and Alzheimer-'s disease phenotypes. Alzheimer-'s, 2026; 22 (6) DOI: 10.1002/alz.71516