OSA severity, LC-NE function, DNA methylation and Neurodegeneration Risk
How does sleep apnea affect brain systems involved in alertness and stress, and how might this contribute to brain aging and Alzheimer’s disease?
Background
Obstructive sleep apnea is a common sleep disorder in which breathing repeatedly stops and starts during sleep. These breathing problems cause frequent awakenings, poor sleep quality, and daytime tiredness. Sleep apnea is especially common in older adults, yet many people do not know they have it. Research suggests that poor sleep from sleep apnea may speed up brain changes linked to memory loss and neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, and Progressive Supranuclear Palsy.. One brain system that may be especially affected is a small region in the brainstem called the locus coeruleus–norepinephrine (LC-NE) system, which helps control alertness, attention, stress, and sleep. This region is also one of the first parts of the brain damaged in Alzheimer’s disease. Ongoing strain on this system, combined with long-term stress and social challenges, may place additional stress on the brain and contribute to faster biological aging, which can be measured using blood tests. Despite these links, scientists still do not fully understand how sleep apnea leads to these brain changes or how sleep, stress, and brain aging work together to increase risk of developing neurodegenerative disease.
Research Plan
The researchers will study older adults with and without moderate-to-severe sleep apnea to better understand how sleep problems affect brain health. Participants will take part in overnight sleep studies, memory testing, brain scans, and blood tests. The brain scans will be used to examine brain structure and measure levels of tau, a brain protein linked to Alzheimer’s disease and others, as well as to assess the brain system involved in alertness and stress. Blood samples will be collected to estimate biological aging. The study will also account for stress levels and social factors that may influence brain health. By bringing these different measures together, the researchers aim to clarify how sleep apnea may lead to faster brain aging.
Impact
This study could help explain why sleep apnea is linked to memory loss diseases like Alzheimer’s disease and other dementias. The findings may support earlier identification of people at higher risk and guide new approaches that focus on improving sleep and reducing stress to protect brain health as people age.