Study finds daytime sleepiness may be linked to pre-dementia syndrome

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If you find yourself drowsiness during daily activities at an older age, you may have to accept this as more than an inconvenience, since fatigue may indicate that you are at higher risk of developing a condition that may lead to dementiashowed a new study.

Among participants who experienced excessive daytime sleepiness and lack of enthusiasmAccording to the study, 35.5% developed motor-cognitive risk syndrome, compared with 6.7% of people without such problems. study published Wednesday in the journal Neurology.

Motor cognitive risk syndrome, or MCR, is characterized by slow walking speed and complaints of memory problems among older people who do not already have dementia or limited mobility. Risk of developing dementia more than doubled in people with this syndrome, which was first described in 2013.

“Previous studies have shown an association between sleep disturbances and the risk of dementia,” first study author Dr. Victoria Leroy, assistant professor of geriatric medicine at the University Hospital of Tours in France, said in an email.

But according to the study, some of these scientific reports looked at this connection primarily at just one point in time. Little is known about the connection between some aspects of poor sleep and predementia syndromes, Leroy and the research team wrote, so they wanted to expand research in this area.

“Establishing the link between sleep dysfunction and risk of MCR is important because early intervention may offer the best hope of preventing dementia,” the authors said.

The results are based on 445 adults, with a mean age of 76 years, recruited from Westchester County in New York for the Central Monitoring of Mobility and Aging Study, which assesses cognitive processes and brain mechanisms that regulate mobility in aging. Participants walked on treadmills so their initial gait could be recorded and then assessed annually from 2011 to 2018.

The study authors also collected yearly data on participants’ recall of sleep quality and quantity in the two weeks preceding the assessments. Specifically, the team compiled details of seven components of the Pittsburgh Sleep Quality Index: subjective sleep quality, time taken to fall asleep, sleep duration, sleep efficiency (ratio of total hours slept to total hours in bed), sleep disturbances, use of sleep-inducing medications , and daytime dysfunction, such as trouble staying awake during activities or decreased enthusiasm for getting things done.

During the follow-up period, which averaged approximately three years, 36 participants developed motor-cognitive risk syndrome. Compared to good sleepers, poor sleepers had only a slightly higher risk of MCR. But when the authors looked at the seven sleep components separately, only daytime dysfunction was associated with a 3.3-fold increased risk of MCR.

The study’s findings could help doctors and patients ask more openly about sleep patterns and monitor walking speed more closely when making an early diagnosis, said Dr. Richard Isaacson, director of research at the Florida Institute for Neurodegenerative Diseases. Richardson was not involved in the study.

The study has several “serious” limitations, Dr. Tara Spiers-Jones, a professor of neurodegeneration and director of the Center for Brain Research at the University of Edinburgh in Scotland, said by email.

“Sleep measurements were taken by self-reporters, not by scientists, and these self-reports may be biased by people with memory problems,” said Spiers-Jones, who was not involved in the study. “The study participants were also mostly white and the group was much smaller than similar concurrent studies, so the results will be more compelling if they are confirmed in future studies.”

The authors acknowledged that although their study duration of approximately three years is longer than some previous studies, the follow-up period is still short.

Motor cognitive risk syndrome was recently discovered, so experts still have a lot to learn before they can explain it in detail what causes it and how it affects the body, Isaacson said. The situation is complicated by the lack of “defined pathological biomarkers” for MCR, Isaacson said.

But “several mechanisms could explain this association,” LeRoy said. “Sleep plays a role in clearing out neurotoxins accumulated in the brain. In addition, previous studies have shown greater accumulation of proteins associated with Alzheimer’s disease in sleep-deprived people.

“One possible alternative or complementary pathway is by activating the inflammatory response in the brain, which is seen in Alzheimer’s disease and related dementias,” LeRoy said.

It’s unclear why, of the seven sleep components, daytime dysfunction was the only one significantly associated with MCR risk, when one would think that the other six components, including sleep quality and quantity, would play a role in daytime dysfunction, experts say.

Spiers-Jones noted that a potential link between daytime dysfunction and MCR A reverse cause-and-effect relationship is also possible.

“Scientific evidence suggests that in the early stages of dementia, pathological changes in the brain disrupt sleep,” she added, meaning that “it is likely that it is an early disease that causes sleep disturbance rather than a disorder that causes disease.”

It is well known that sleep disorders such as REM sleep behavior disorder may be early predictors of conditions including Dementia with Lewy bodies or Parkinson’s disease, Isaacson said.

The study results show how valuable sleep is, LeRoy said.

People having sleep problems they should talk to their doctors, consider completing a sleep questionnaire and discuss whether a sleep study at home or in the hospital might be helpful, Isaacson said.

“There are now many treatments, both drug and non-drug, that can help depending on the specific problem found,” he added. “Treating sleep disorders should pay dividends for years, even decades, in overall brain health and dementia prevention.”

You can take other steps to protect your brain as you age.

“A healthy lifestyle, including eating right, maintaining a healthy weight, keeping the body and brain active, and treating any hearing loss are all ways to improve brain resilience and likely reduce the risk of dementia,” Spiers-Jones said.

“We don’t blame people with dementia for their lifestyle choices,” she added. “The best estimates suggest that less than half the risk of dementia is due to this type of modifiable risk factor, and the rest of the risk is likely due to genes that we inherit.”

However, given potential to change your risk and the growth in medical research and treatments, Spiers-Jones added, provides cause for hope.

According to Isaacson, if you’re already experiencing mobility problems, you may benefit from falls prevention, which may include evaluation of physical and occupational therapy, as well as at-home adaptations such as installing screens in the shower, removing clutter and use of night lights.