Napping characteristics and cognitive performance in older adults

Abstract

Objectives: To determine the association of napping intention, frequency, and duration with cognition in a nationally-representative sample of U.S. older adults. Methods: We performed a cross-sectional analysis of community-dwelling Medicare beneficiaries aged ≥65 years from Rounds 3 or 4 (2013–2014) of the National Health and Aging Trends Study (N=2,549). Participants reported past-month napping intention (intentional/unintentional), napping frequency (rarely/never [non-nappers], some days [infrequent nappers], most days/every day [frequent nappers]), and average nap duration (we categorized as ≤30 minutes [short]; 31–60 minutes [moderate]; and >60 minutes [long]). Cognitive outcomes were performance on immediate and delayed word recall tests (IWR and DWR, respectively), the Clock Drawing Test (CDT), and self-rated memory (score: 1[excellent]-5[very poor]). Results: After adjustment for potential confounders, unintentional nappers had poorer immediate word recall test performance than non-nappers (B=−0.23, p<0.01) and intentional nappers (B=−0.26, p<0.01). After further adjustment for daytime sleepiness, frequent nappers reported poorer self-rated memory than non-nappers (B=0.14, p<0.05). Compared to short nappers, long nappers had poorer IWR (B=−0.26, p<0.05) and CDT scores (B=−0.17, p<0.05). Except for the association of nap duration with IWR and CDT, these associations remained after excluding participants with dementia and/or proxy respondents. Among participants undiagnosed with dementia or proxies, moderate-duration naps were associated with better DWR than short naps (B=0.24, p<0.05). Neither napping intentionality nor frequency were associated with CDT performance. Conclusions: Among older adults, distinct aspects of napping are associated with cognitive performance. Prospective research, with objective measures of napping, is needed to elucidate the link between napping and cognitive trajectories.

Short Daytime Napping Reduces the Risk of Cognitive Decline in Community-Dwelling Elderly Individuals: a 5-Year Longitudinal Study

“…Cross et al [9] reported that longer napping is signi cantly correlated with increased levels of cognitive de cits in 133 adults aged >50 years. Similarly, Owusu et al [11] showed that unintentional, longer naps were correlated with poorer performance on cognitive tests in 2,549 community-dwelling adults aged ≥65 years. While these studies suggested the unfavorable effect of longer napping, shorter napping reportedly had a favorable effect on cognitive performance [21].…”

“…According to recent reviews and meta-analyses, sleep duration and sleep disturbance are determinants of cognitive decline and dementia [3][4][5][6][7]. Moreover, daytime napping is reportedly associated with cognitive function in older adults [8][9][10][11]. However, previous study ndings have been somewhat inconsistent; some reported possible adverse effects of napping, especially long napping, on cognitive function [9,11], whereas others reported possible bene cial effects of napping, especially short napping [8,10].…”

“…Moreover, daytime napping is reportedly associated with cognitive function in older adults [8][9][10][11]. However, previous study ndings have been somewhat inconsistent; some reported possible adverse effects of napping, especially long napping, on cognitive function [9,11], whereas others reported possible bene cial effects of napping, especially short napping [8,10]. Furthermore, except for one longitudinal study [8], only cross-section studies [9][10][11] have been conducted.…”

“…However, previous study ndings have been somewhat inconsistent; some reported possible adverse effects of napping, especially long napping, on cognitive function [9,11], whereas others reported possible bene cial effects of napping, especially short napping [8,10]. Furthermore, except for one longitudinal study [8], only cross-section studies [9][10][11] have been conducted. More longitudinal studies are awaited to accumulate evidence of higher levels.…”

Relationship between afternoon napping and cognitive function in the ageing Chinese population

“…Longer daytime sleep develops the habit of sitting for a long time, reducing social activity and cognitive function. 18 It had also been found 20 that unintentional nappers had an immediate poorer performance in the word recall test than non-nappers and intentional nappers. A number of factors, such as the timing, duration, frequency, and planned or unplanned nature of naps, need to be considered when determining the benefit of daytime napping.…”