A new study revealed that frequent or regular napping for an extended time throughout the day may be connected to signs of early dementia in elderly adults.
The study published last Thursday in “Alzheimer’s and Dementia,” the Journal of the Alzheimer’s Association, revealed a relationship between excessive daytime napping and dementia. According to the study, older adults who napped at least once a day or more than an hour a day had 40% more chances to develop Alzheimer’s symptoms than those who did not take a daily nap or napped less than an hour a day.
We found the association between excessive daytime napping and dementia remained after adjusting for nighttime quantity and quality of sleep.
Dr. Yue Leng, Assistant Professor of Psychiatry at the University of California, San Francisco
When people age, sleep quality and quantity declines due to pain or complications from chronic conditions (e.g., bathroom breaks). This is why older adults have a higher need of taking naps than they did when they were younger. However, Dr. Leng clarified that day naps can also be a sign of brain changes that are unrelated to nighttime sleep.
Excessive napping may be one of the many clues that a person could be on the road to cognitive decline, and trigger an in-person evaluation with a treating physician.
Dr. Richard Isaacson, Director of the Alzheimer’s Prevention Clinic in the Center for Brain Health at Florida Atlantic University’s Schmidt College of Medicine
The study is based on data collected over 14 years by the Rush Memory and Aging Project, which gathered information on more than 1,400 people with an average age of 81. For 14 days every year, the study’s participants wore a tracker that allowed researchers to capture data on their movements. No movement signs for an extended period between 9 am and 7 pm were interpreted as a nap time.
Speaking with CNN, Leng specified that they have created a unique algorithm to differentiate naps from no activity, such as watching TV. She added that they were more focused on the total nap minutes accumulated throughout the day, and the change in the naps’ length over the years.
Regardless of the reason, falling asleep during the day or excessive napping raises my antenna to focus on whether the person may be at higher risk for Alzheimer’s disease or cognitive decline.
Dr. Richard Isaacson, Director of the Alzheimer’s Prevention Clinic in the Center for Brain Health at Florida Atlantic University’s Schmidt College of Medicine
The new study found that over the 14 years, daytime napping increased on average by 11 minutes per year for adults who did not develop cognitive impairment. However, people who were diagnosed with mild cognitive impairment napped on average 24 minutes a day, while participants who were diagnosed with Alzheimer’s napped on average 68 minutes a day.
Dr. Leng added that she does not believe the study provides enough evidence to conclude that it’s the napping itself that causes cognitive aging, although extended daytime naps might be a signal of accelerated cognitive aging process. For this reason, adults should limit any daytime naps to 15/20 minutes before 3 pm.
The results of the new study are in line with the findings of a previous research (“Objective napping, cognitive decline, and risk of cognitive impairment in older men”) conducted by Dr. Leng. The study found that men who napped for more than 2 hours a day were 66% more likely to develop cognitive impairment in 12 years.