Excessive napping may signal cognitive decline
Napping may indicate cognitive decline in elderly adults in the long run, a recent study has shown.
The study included 2,751 community-dwelling elderly men (mean age, 76.0 years), in whom napping was assessed using wrist actigraphy. Cognition was assessed over a 12-year period. Clinically significant impairment in cognition was defined as a physician diagnosis or the use of Alzheimer’s disease medication.
Overall, the mean napping duration of the entire study was 42.0 minutes. Majority (51.2 percent; n=1,490) of the participants napped for <30 minutes per day and only 5.4 percent (n=253) recorded napping lengths of ≥120 minutes per day. Those who napped longer tended to have higher body mass index and greater depressive symptoms.
Over 12 years of follow-up, the scores in the Modified Mini Mental State Examination were 4.2, 5.2, 4.3 and 5.6 in men who napped for <30, 30–59, 60–119 and ≥120 minutes per day, respectively. The trend was statistically significant (p<0.001).
After controlling for age, education, smoking, physical activity and other confounders, multivariable logistic regression analysis showed that relative to those who napped for <30 minutes per day, men who spent 30–59 (odds ratio [OR], 1.21, 95 percent CI, 0.89–1.64) and 60–119 (OR, 1.18, 0.85–1.63) minutes napping were nominally more likely to develop cognitive impairment.
Notably, the risk difference was statistically significant in those who napped for ≥120 minutes per day (OR, 1.66, 1.09–2.54).
“Future studies are needed to examine the underlying mechanisms of these associations,” researchers said. “This might provide insights into the early detection of dementia and open up new opportunities for prevention of dementia through better management of 24-hour sleep-wake cycles.”