Disrupted sleep may directly harm brain blood vessels and accelerate the progression of dementia, according to findings from Canadian researchers at Sunnybrook Health Sciences Centre and the University of Toronto. Their study, published in the journal Brain, is the first to demonstrate at a cellular level how fragmented sleep impacts cerebral blood flow.
The Research Behind the Findings
The study involved over 600 elderly participants whose sleep activity was monitored using wearable sensors. Following their deaths, their brains were analyzed for alterations in pericytes – specialized cells that regulate permeability and blood flow within brain vessels, crucial for maintaining a healthy brain environment.
Fragmented Sleep: A Causal Link?
It was discovered that individuals with the most disturbed sleep exhibited an imbalance in pericytes. This cellular change correlated with a more rapid decline in cognitive functions during their final years. Researchers emphasize that fragmented sleep, characterized by frequent awakenings throughout the night, might not merely be a symptom of existing brain issues but a direct cause of vascular impairments and neurodegeneration.
Pathways to Prevention
The authors suggest that improving sleep quality and specifically targeting pericytes could open new avenues for dementia prevention and treatment. The next crucial step involves clinical trials to assess the impact of various sleep therapies on brain vascular biomarkers, paving the way for potential interventions.
Beyond Fragmented Sleep: The Dangers of Oversleeping
Adding another layer to the understanding of sleep and brain health, separate research from May also identified that excessively long sleep can be detrimental. Scientists found that sleeping nine hours or more per night is associated with impaired memory and thinking abilities, indicating that both too little and too much sleep can negatively affect cognitive function.
