Poor Sleep in Older Adults Linked to Disruptions in the Brain’s Waste Removal System, Study Finds

Researchers at The University of Hong Kong (HKU) have discovered a significant connection between poor sleep quality in older adults and dysfunction in the brain’s natural waste clearance system. A recent study, led by Professor Tatia M.C. Lee, Chair Professor of Psychological Science and Clinical Psychology and May Professor in Neuropsychology at HKU, provides critical insights into how sleep quality influences brain health and cognitive function.

While previous studies have linked poor sleep with cognitive decline, Professor Lee’s team focused on the glymphatic system—a fluid transport network responsible for clearing toxic waste from the brain. The efficiency of this system is vital for brain health, particularly in aging populations.

The research explored how glymphatic dysfunction in poor sleepers contributes to memory decline. An impaired glymphatic system can lead to the accumulation of toxic proteins, which has been linked to neurological disorders such as Alzheimer’s disease, Parkinson’s disease, and epilepsy.

“Sleep quality, brain activity, and glymphatic function are interconnected,” said Professor Lee. “Understanding how sleep affects this waste clearance system and brain networks provides valuable insight into the neurophysiological mechanisms behind age-related memory changes.”

The study involved 72 older adults, who underwent functional MRI scans and sleep recordings. The findings revealed that poor sleep disrupts normal brain function by impairing the glymphatic system’s restorative processes, ultimately affecting memory performance.

“The results clearly demonstrate how sleep influences the brain’s network via the glymphatic system, which in turn impacts memory in older adults,” Professor Lee explained. “Maintaining an efficiently functioning glymphatic system is crucial for supporting healthy aging.”

These findings contribute to the growing body of evidence linking sleep quality to cognitive health through complex neural interactions. “Memory impairment is a common issue among older adults with poor sleep,” Professor Lee noted. “Our study offers a novel perspective on the relationship between sleep, the glymphatic system, and multimodal brain networks.”

This research was recently published in Molecular Psychiatry under the title “Effects of Sleep on Glymphatic Functioning and Multimodal Human Brain Networks Affecting Memory in Older Adults.”

Source: https://www.hku.hk/press/news_detail_28168.html