Napping too long could be a sign of dementia

In a recent cohort study, published in the journal Alzheimer’s & Dementia, researchers found that taking naps for more than an hour or taking them several times a day could be an early sign of Alzheimer’s disease.

a warning sign

Research suggests that excessive daytime napping shares a bidirectional relationship with cognitive decline, reflecting and shaping changes in the brain.

The researchers, from Harvard and California University in San Francisco, USA, tested two hypotheses: (1) participants take longer and/or more frequent naps with age, and the changes are even more rapid with the progression of Alzheimer’s disease; and (2) participants with excessive daytime naps have a higher risk of developing Alzheimer’s disease. The participants wore a mobility tracker for a two-week period once a year, with follow-up for up to 14 years. The volunteers also underwent a series of neuropsychological tests to assess cognition once a year.

“The daytime sleep behaviors of older adults are often ignored, and a consensus for daytime napping in clinical practice and healthcare is still lacking ,” said Peng Li, co-author of the paper.

Analyzing the nap

By comparing daytime sleep patterns, they found that nappers were at higher risk of developing Alzheimer’s.

The experts noted that the participants (1,401 seniors with an average age of 81) tended to nap longer and more frequently as they got older; More importantly, the progression of Alzheimer’s dementia appeared to accelerate this aging effect by doubling or even more than annual changes in nap duration/frequency, producing a “vicious circle” between afternoon naps and afternoon naps. memory-robbing disorder

Specifically, those older people who took a nap once a day were 40% more likely to develop Alzheimer’s, which is the most common type of dementia. But sleep duration was also important, as the study results also showed that longer and more frequent daytime naps were associated with a higher risk of developing Alzheimer’s. Sleeping more than one hour a day of siesta was comparable to the highest percentage of risk for the elderly.

Is napping bad for the brain?

Although, according to the authors, the study does not show any evidence that napping can age the brain, it does show that “excessive daytime naps could be a sign of an accelerated aging process or cognitive aging.” experts clarify.

In fact, excessive daytime sleepiness, which may be the cause of longer and more frequent naps, has also been linked to faster cognitive decline or the accumulation of Alzheimer’s disease pathology. This is because arousal deficiency due to neuronal and neurotransmitter loss in wake-promoting neurons causes sleep and wake disorders and a greater propensity for daytime naps.

Referencia: Peng Li et al. Daytime napping and Alzheimer’s dementia: A potential bidirectional relationship. Alzheimer’s & Dementia, published online March 17, 2022; doi: 10.1002/alz.12636