The research, led by Associate Professor Matthew Pase, highlights the importance of slow wave sleep in maintaining cognitive health as we age.
The Study’s Key Discovery
The study focused on 346 participants over the age of 60, who were part of the Framingham Heart Study. The individuals completed two overnight sleep studies between 1995-1998 and 2001-2003, with an average of five years between the two sessions. Over the course of 17 years, researchers monitored the participants for the development of dementia.
The researchers made a startling revelation: even a mere 1 percent annual reduction in deep sleep, also known as slow wave sleep, corresponded to a staggering 27 percent increase in the risk of dementia. This suggests that the maintenance or enhancement of deep sleep can play a crucial role in preventing dementia.
The Importance of Slow-Wave Sleep
Deep sleep, or slow wave sleep, offers extensive support to the ageing brain. During this phase of sleep, the brain clears metabolic waste, including proteins associated with Alzheimer’s disease.
Slow wave sleep is essential for overall brain health, and its loss has been linked to cognitive decline.
“We know that sleep augments the clearance of metabolic waste from the brain, including facilitating the clearance of proteins that aggregate in Alzheimer’s disease,” explains Associate Professor Pase.
One of the key takeaways from this research is that slow wave sleep loss may be a modifiable risk factor for dementia. This implies that there are strategies and lifestyle adjustments that individuals can adopt to maintain their cognitive health as they age.
Unique Insights from the Framingham Heart Study
The Framingham Heart Study stands out as a unique community-based cohort that allowed researchers to monitor participants’ sleep patterns over time. This extensive dataset provided invaluable insights into how slow wave sleep changes with ageing and its impact on dementia risk.
The study also explored the role of genetic factors in Alzheimer’s disease and their connection to changes in slow-wave sleep. The researchers found that a genetic risk factor for Alzheimer’s disease was associated with accelerated declines in slow wave sleep.
This groundbreaking study underscores the significance of deep sleep in the fight against dementia. With the knowledge that slow wave sleep loss may be a modifiable risk factor, older adults and healthcare professionals have a new avenue to explore in preserving cognitive health.