Excessive Napping in the Elderly May Be an Early Sign of Alzheimer’s Dementia

Table of Contents

1 Daytime sleepiness, or the urge to sleep during the day
2 Daytime sleepiness is independent of nighttime sleep
3 Increased napping duration after Alzheimer’s diagnosis
4 Those who take more naps are more likely to develop Alzheimer’s
- - 4.0.1 References

In the US, 5.8 million people were affected by Alzheimer’s disease in 2020, according to the CDC. This pathology is caused by the degeneration of neurons in the brain and is characterized by several symptoms: memory problems, the execution of simple movements, orientation in time and space, and cognitive functions. Some patients also suffer from sleep disturbances. The latter is very important for many neurodegenerative diseases. According to a study published in Alzheimer’s and Dementia: The Journal of the Alzheimer’s Association, people who suffer from excessive daytime sleepiness are actually more likely to suffer from dementia and Alzheimer’s disease in the future.

A Woman With Alzheimer

Daytime sleepiness, or the urge to sleep during the day

Daytime sleepiness is a classic phenomenon of aging. It is a problem suffered by some people – often older people – who tend to fall asleep in the middle of the day. If they are young and active and therefore cannot take as many naps as they need, they often have to fight this urge to sleep. Daytime sleepiness is usually caused by the need to compensate for poor sleep at night. But that is not the researchers’ theory.

Daytime sleepiness is independent of nighttime sleep

We observed that the link between the need to take naps – due to excessive daytime sleepiness – and dementia did not change, even when people had sufficient quality and quantity of sleep at night “, explains Yue Leng, one of the authors. This suggests that daytime sleepiness plays an important role in itself and is independent of nighttime sleep.”

According to the researchers, daytime sleepiness may, in some cases, be a precursor to future dementia, such as Alzheimer’s disease. And once diagnosed, this need for sleep will increase even more with age.

Increased napping duration after Alzheimer’s diagnosis

To reach this conclusion, the researchers analyzed data from 1,401 older people, who were 81 years old on average and about three-quarters of whom were women. They were followed for several years, up to 14 years. All of these participants wore a watch-like device connected to a continuous unit that recorded their activity for about 14 days a year. At the same time, they also underwent neuropsychological tests to assess the evolution of their cognitive abilities. At the beginning of the study, 75.7% of the participants had no cognitive impairment, 19.5% had mild cognitive impairment, and 4.1% had Alzheimer’s disease.

At the end of the study, participants who had not developed a cognitive impairment took an extra 11 minutes of nap time. In contrast, after a diagnosis of cognitive impairment, this increase was 24 minutes, and for those with Alzheimer’s disease, 68 minutes.

Those who take more naps are more likely to develop Alzheimer’s

The researchers sought to understand whether sleep also had a link to the development of the disease. They found that participants who took a nap more than an hour a day before becoming ill had a 40 percent higher risk of developing Alzheimer’s disease than those who took a nap less than an hour a day. In addition, those who slept at least once a day were also 40 percent more likely to develop the disease than those who slept less than once a day.
“I don’t think we have enough evidence to conclude that there is a link between napping and cognitive aging, but excessive daytime sleepiness may be a sign of accelerated aging or a cognitive aging process,” Yue Leng concludes. The researchers now want to continue their research to further assess the impact of daytime sleepiness on neurodegenerative diseases.