Your Sleep Need May be Driven by Poor Drainage of Brain Waste

Jun 21, 2021 | Blog, Science Simplified

Study highlights potential new treatment approaches for sleepiness

Sleep is a crucial part of our health and wellbeing. Not only do we feel rested after a good night’s sleep, but behind the scenes, important functions are taking place which help keep us healthy. Our brain clears out the day’s metabolic waste while we sleep. This clearance is believed to be carried out though the flow of the cerebrospinal fluid (CSF) – traveling through the brain’s small blood vessels and passing through perivascular spaces that surround some of these vessels.

A recent ONDRI study1 suggests that the efficiency of this waste drainage system could be one determinant of a person’s sleep need. If the perivascular spaces are blocked – preventing proper drainage – then a person may need more sleep to feel rested. While the focus of the findings was on people living with cerebrovascular disease (CVD), this connection could be true for the general population.

Why is this important?

“This research finding paves the way for a potential new treatment modality for people who suffer from excessive sleepiness, along with the harmful impacts that poor sleep has on the body. If we can improve CSF drainage for people who require it, then we may be able to improve their sleep efficiency. This means they could gain all the benefits of a good night’s sleep, while sleeping fewer hours”, said Dr. Andrew Lim, Staff Neurologist with a research focus on Sleep, at Sunnybrook Health Sciences Centre.

“This area of sleep medicine is new and exciting and needs to be explored further,” continued Dr. Lim.

More on the research

This ONDRI research analyzed the data set of 151 people living with CVD, who participated in ONDRI’s Foundational Study. Researchers compared perivascular space (PVS) volumes, which were quantified based on MRIs, to the groups’ reported sleep history and sleep behaviour.

When corrected for every other factor, the study found that participants with greater enlarged PVS volumes (suggesting blockage), slept more hours per night than participants with lower volumes of PVS.

The ONDRI study’s high-quality MRIs and comprehensive neuroimaging protocols enabled clinicians and researchers to more clearly visualize these tiny perivascular spaces. In addition, whereas in other studies researchers often simply count the number of perivascular spaces – for a crude measure of PVS burden – ONDRI researchers quantified the actual volumes of these perivascular spaces. This allowed a higher degree of sensitivity of results.

This measurement of volume was facilitated through advanced techniques that were developed in the same lab in years prior.2

The convergence of brain and sleep sciences is an exciting, emerging area, that is highly relevant, particularly as the population ages and dementia becomes a growing societal burden.

And let’s face it, with everything going on these days, couldn’t we all benefit from a better night’s sleep?

Andrew Lim, MD

Andrew Lim, MD