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Take a nap frequently or for a long time during the day could be a sign of Alzheimer’s or dementia, reveals a study published in the Journal of Alzheimer’s Disease on Thursday.
The study authors believe it is more likely that Excessive naps are a ‘warning sign’ of declining cognitive healthpointed out one of the researchers, Yue Leng, an assistant professor of psychiatry at the University of California, quote it the Guardian.
You data was collected over 14 years fur Memory and Aging Project, from Rush University in the United States, to more than 1,400 people between the ages of 74 and 88, an average of 81 years. For 14 days a year, participants wore a device that tracked their movements, and each period of prolonged inactivity from 9 a.m. to 7 p.m. was interpreted as a nap.
In addition, at the start of the survey, 76% of the elderly had no cognitive deficit, 20% had only mild disorders and 4% had Alzheimer’s disease.
During the study period, naps increased by an average of 11 minutes per year for adults who did not develop suspicious behaviors. However, people diagnosed with Alzheimer’s nearly tripled their nap time to an average of 68 minutes a day. Those with a slight deficit started sleeping 24 minutes a day.
In general, older people who took a nap at least once a day or more than an hour were 40% more likely to develop Alzheimer’s disease than those who have not slept or slept less.
Insomnia and poor nighttime sleep patterns are common in people with dementia, but recent work has shown that “the association between prolonged naps and dementia persisted after sleep adjustment,” Leng said. “This suggests that the role of the daytime nap is important in itself”. Besides, previous surveys highlighted the benefits of a nap on mood, attention, and performance on mental tasks.
The assistant professor of psychiatry, however, noted that that there is neither “sufficient evidence” nor “any obvious biological mechanism” to trace a causal relationship that “it is the nap itself that causes cognitive aging”. He only specified that it is “a sign” of the existence of dementia or Alzheimer’s disease.
Already in another studyLeg had concluded that those who slept two hours a day had an increased risk of cognitive impairment compared to those who slept less than 30 minutes.