The Sleep System That Could Influence Dementia Risk

Published: 05 September. The English Chronicle Desk

Recent research suggests that the brain’s own waste removal system, known as the glymphatic system, may play a crucial role in reducing the risk of dementia, and that quality sleep could be key to its effectiveness. While most studies have been conducted in mice, evidence increasingly indicates that disrupted sleep may hinder the clearance of toxins from the brain, potentially increasing vulnerability to conditions such as Alzheimer’s disease.

The glymphatic system functions similarly to the lymphatic system elsewhere in the body, moving cerebrospinal fluid around the brain to collect and remove waste. Among the waste products cleared is amyloid beta (Aβ) protein, which can accumulate in plaques, a hallmark of Alzheimer’s disease. Research in both humans and animals shows that levels of Aβ rise during waking hours and fall during sleep, reinforcing the importance of restorative sleep for brain health.

However, some recent studies in mice challenge the assumption that the system is exclusively more active at night, prompting ongoing debate about the precise mechanisms and timing of toxin clearance in humans. Nevertheless, sleep is known to support memory and cognitive function, and a single night of sleep deprivation has been shown to increase Aβ in the human hippocampus, suggesting the system’s activity is indeed influenced by sleep.

Sleep disorders such as sleep apnoea, which causes repeated interruptions in breathing and chronic sleep deprivation, may further compromise the brain’s ability to eliminate harmful proteins. Yet it remains uncertain whether treating these conditions directly reduces dementia risk. Current research is exploring how interventions, including sleep disorder treatments and medications like orexin receptor antagonists, might enhance the glymphatic system’s efficiency.

While the science is still developing, these findings underscore the importance of consistent, high-quality sleep for brain health. Individuals concerned about their sleep or cognitive well-being are encouraged to consult medical professionals for guidance and support.