There are currently more than 55 million peopleTrusted Source around the world living with dementia, and researchers estimate that someone in the world develops dementia every three seconds. As the number of people with dementia is expected to hit about 153 million by 2050Trusted Source, researchers have been working hard to find more ways to lower a person’s risk of developing this neurological disease. Now, a new study provides more proof by finding that as little as a 1% reduction in deep sleep — also called slow-wave sleep — each year for people over 60 years of age equals a 27% increased risk of developing dementia.
For this study, researchers from Monash University in Melbourne, Australia examined data from 346 study participants over the age of 60 enrolled in the Framingham Heart Study. All of the chosen participants had completed two overnight sleep studies, with about five years between each sleep study.
Researchers reported that, on average, the amount of deep sleep each participant had declined between the two studies, indicating slow-wave sleep loss due to aging.
Scientists also followed the study participants from the time of their second sleep study until 2018, looking for dementia diagnoses. “Responding to the rising prevalence of dementia is one of the most critical challenges of our time,” Dr. Matthew Pase, associate professor at the Monash School of Psychological Sciences and the Turner Institute for Brain and Mental Health in Melbourne, Australia, and senior author of this study told Medical News Today.
“Since we don’t have any readily available curative treatments to halt or reverse dementia permanently, we were interested in understanding ways in which dementia can be prevented in the first instance,” he said.
“For the purpose of informing dementia prevention guidelinesTrusted Source, we were interested in clarifying how sleep changed with aging and whether changes in sleep with aging were associated with dementia risk,” he added.
Even after adjusting for a variety of factors, including age, sex, and sleeping medication use, researchers found each percentage decrease in deep sleep each year was associated with a 27% increase in the risk of dementia.
