A new study finds sleeping on your back could increase your risk for neurodegenerative disorders, such as Alzheimer’s disease and Parkinson’s disease

Does Sleeping on Your Back Affect Brain Health? New Study Suggests Possible Link Here's why sleeping on your back might increase your risk of neurodegeneration and how you can find out if you’re a back sleeper

A new study finds sleeping on your back could increase your risk for neurodegenerative disorders, such as Alzheimer’s disease and Parkinson’s disease

• A new study found sleeping in a supine position may be associated with neurodegeneration, such as Alzheimer’s disease, Parkinson’s disease, and other neurodegenerative disorders.
• Experts suggest that sleeping on your back might be linked to neurodegeneration because it can result in less efficient removal of brain toxins, which can accumulate and worsen over time.
• More research is needed to determine if sleeping on your back, along with other positions, might increase the risk of neurodegeneration.

It’s well established that getting adequate sleep at night is crucial for good health—but when it comes to the brain, it may not just be the amount of shut-eye you get that matters but the position you sleep in, too. 

That’s the finding of a recent exploratory study presented at the 2024 Alzheimer’s Association International Conference that suggests that sleeping on your back, known as the supine position, may be linked to an increased risk of Alzheimer’s disease, Parkinson’s disease, and other neurodegenerative disorders.

“Our research has established a strong association between supine sleep and neurodegeneration, but it’s yet to be proven whether supine sleep causes neurodegeneration,” said lead author Daniel J. Levendowski, president and co-founder of Advanced Brain Monitoring, a company that sells neuro-diagnostic devices and funded the research.

The study appears to strengthen pre-existing evidence of a connection between back sleeping and a higher risk of neurodegenerative diseases. However, the research hasn’t been peer-reviewed and has other significant limitations, according to Diego R. Torres-Russotto, MD, chair of neurology at Baptist Health Miami Neuroscience Institute, part of Baptist Health South Florida.

Here’s what you need to know.

Finding a Link Between Back Sleeping and Neurodegenerative Disease

The connection between back sleeping and neurodegenerative disease was first discovered back in 2015, Levendowski said, when an experiment using mice found that sleeping in the supine position could contribute to neurodegeneration.

In 2019, Levendowski and his colleagues investigated the question using 45 humans with neurogenerative disease. They found that sleeping in a supine position—specifically, for more than two hours a night—was associated with a higher risk of neurodegenerative diseases.

For the newest study, Levendowski and his colleagues dug in even further, this time recruiting about a hundred relatively healthy people to serve as a control group and roughly 200 participants with mild cognitive impairment, progressive supranuclear palsy, and Alzheimer’s disease. Some participants also had Parkinson’s spectrum disorders (PSD), an umbrella term for disorders characterized by abnormal accumulation of proteins.

Researchers studied the participants at home using the Sleep Profiler, a device developed by Advanced Brain Monitoring. The device tracked how many hours per night the participants spent sleeping in a supine position.

“The Sleep Profiler software extracts nine key biomarkers useful in characterizing neurodegenerative disorders subtypes,” Levendowski said. “Time spent sleeping in the supine position is one of the nine biomarkers.”

They found that participants with neurodegenerative conditions slept on their backs for over two hours more often than people in the control group.

“This study provides further evidence for a relatively strong association between supine sleep and neurodegeneration in PSD, [Alzheimer’s disease,] and [mild cognitive impairment] cohorts,” the authors wrote in their presentation.

They also noted, however, that more studies are needed to find out if sleeping on your back causes the development of neurodegenerative diseases.

The Limitations

While the findings are intriguing and could suggest that sleep position might be a modifiable risk factor for developing neurodegenerative diseases, there are important limitations to be aware of, Torres-Rusotto told Health.

First, the results have only been presented as abstracts at a scientific meeting and still need more rigorous peer review before they can be published. Torres-Russotto also noted that the participants with neurodegenerative conditions and the control group weren’t well matched; for example, the control group was younger and had more female participants.

“These and other limitations could mean that the differences seen between the sleeping positions in this study could be due to the two populations not being statistically comparable,” Torres-Russotto said.

“Lastly,” he said, “an important consideration is that this study was presented, written, and sponsored by officers of a company that sells devices for sleep, and therefore there could be additional bias to the results.”

Why Sleeping on Your Back Could Influence Brain Health

Back sleeping may be detrimental to brain health because it leads to conditions that reduce the body’s ability to effectively clear out neurotoxins, Levendowski said.

These neurotoxins, produced by the brain during the day, typically get flushed out during sleep through a process called glymphatic clearance, often called the brain’s “waste management system.” The process starts to become less efficient around midlife, typically 15 to 20 years before people notice any early signs of cognitive decline related to neurodegeneration.

Sleeping on your back may further slow it down, per Levendowski, because the positioning doesn’t easily allow blood to drain from the brain to the heart like it should.

A 2019 study, however, showed that this isn’t the case when people sleep on their sides, Nikhil Palekar, MD, director of the Stony Brook Center of Excellence for Alzheimer’s Disease, told Health in an email. That research showed that side sleeping causes a vein near the heart to partially collapse, helping to improve blood flow and the removal of waste from the brain. “This effect was not seen in the supine sleeping position,” he said.

Another study (albeit on animals) found that back sleeping was specifically less effective at clearing beta-amyloid protein from the brain, which is important because this protein is linked to Alzheimer’s disease, Palekar told Health in an email.

What’s more, Levendowski said, sleeping on your back can worsen sleep apnea, which disrupts sleep and leads to even more toxin buildup.

“Thus, our research suggests inefficient neurotoxin clearance resulting from back sleeping over many years contributes to neurodegeneration,” Levendowski said.

Torres-Russotto noted that while many studies have examined sleep quality and patterns to determine their relationship to brain disorders, “the results so far have been inconsistent, and more data is needed to understand this relationship.”

How To Avoid Sleeping on Your Back

Some people might be well aware that they sleep on their backs, while others have no idea how their body moves during shuteye. Fortunately, you can figure out if you’re a back sleeper or if you tend to sleep on your side or belly. Strategies include:

• Checking your position: When you wake up, take note of your position. If you’re lying flat on your back with your arms at your sides, it could be a sign that you’re sleeping in a supine position. 
• Asking someone: Another way to know is to ask a partner what position you tend to sleep in, Torres-Russotto said.
• Using a sleep tracker: Some devices, such as the Sleep Profiler used in this study, along with other fitness trackers and sleep apps, can help monitor your sleep position and quality, Palekar said.

While there’s no definitive conclusion as to whether sleeping on your back can contribute to the development of neurological disorders, experts said reducing supine sleep is certainly possible if that’s something you’re interested in.

One way to put a stop to your back sleeping habit is to place pillows—whether regular or body ones—on either side of your body that you can hug while you sleep. This could potentially encourage side sleeping, Palekar said.

Levendowski also recommends placing a tennis ball in the back of your pajama top. “The tennis ball in the back or padding to restrict supine sleep uses pain as the deterrent,” Levendowski said. That discomfort may work to your advantage, enticing you to make the switch from supine to side.

This story originally appeared on: Health News - Author:Alyssa Hui