Don’t sleep on this research.
Excessive napping among older adults is strongly correlated with increased risk for Alzheimer’s disease, according to a study published Thursday.
Elderly adults who averaged more than an hour of sleep during the daytime were 40 percent more likely to develop signs of dementia than people who didn’t nap or napped less than an hour, the study in Alzheimer’s and Dementia: The Journal of the Alzheimer’s Association found.
Researchers described it as a “vicious cycle”: More sleep led to an increased risk for dementia, and more dementia led to more sleep for study participants.
“The vicious cycle we observed between daytime sleep and Alzheimer’s disease offers a basis for better understanding the role of sleep in the development and progression of Alzheimer’s disease in older adults,” lead researcher Peng Li said.
More than 1,400 people, with an average age of 81, were involved in the study. Data was gathered through 14 years of research, with participants wearing wristbands that tracked their movement—or lack thereof.
The study found that nap times and dementia risk increased with age. Each year, nap time increased by an average of 11 minutes among participants. But even after accounting for the year-over-year nap increase, signs of dementia still increased, researchers found.
“I don’t think we have enough evidence to draw conclusions about a causal relationship, that it’s the napping itself that caused cognitive aging, but excessive daytime napping might be a signal of accelerated aging or cognitive aging process,” co-author Yue Leng told CNN.
A 2019 study led by Leng found a similar connection between daytime sleep and cognitive decline.
