Sleep Difficulties and Cognition for 10 Years in a National Sample of U.S. Older Adults

Abstract

Background and Objectives Sleep difficulties are common among older adults and are associated with cognitive decline. We used data from a large, nationally representative longitudinal survey of adults over the age of 50 in the U.S. to examine the relationship between specific sleep difficulties and cognitive function over time. Research Design and Methods Longitudinal data from the 2004-2014 waves of the Health and Retirement Study were used in the current study. We examined sleep difficulties and cognitive function within participants and across time (n=16,201). Sleep difficulty measures included difficulty initiating sleep, nocturnal awakenings, early morning awakenings, and waking feeling rested from rarely/never (1) to most nights (3). The modified Telephone Interview for Cognitive Status (TICS-m) was used to measure cognitive function. Generalized Linear Mixed Models (GLMM) were used with time varying covariates to examine the relationship between sleep difficulties and cognitive function over time. Results In covariate-adjusted models, compared to “never” reporting sleep difficulty, difficulty initiating sleep “most nights” was associated with worse cognitive function over time (Year 2014: b=-0.40, 95%CI: -0.63 to -0.16, p<.01) as was difficulty waking up too early “most nights” (Year 2014: b=-0.31, 95%CI: -0.56 to -0.07, p<.05). In covariate-adjusted analyses, compared to “never” reporting waking up feeling rested, cognitive function was higher among those who reported waking up feeling rested “some nights” (Year 2010: b=0.21, 95%CI: 0.02 to 0.40, p<.05). Discussion and Implications Our findings highlight an association between early morning awakenings and worse cognitive function, but also an association between waking feeling rested and better cognitive function over time. Translational Significance Sleep difficulties are common among older adults yet reduce quality of life and also contribute to the development of and potentially accelerate cognitive decline. This study examines specific sleep difficulties (e.g., difficulty falling asleep) and their unique relationship to cognition over time among older adults in the U.S. The primary aim of this work is to illuminate the specific sleep difficulties that are most concerning from the standpoint of cognitive impairment so as to inform the design of future tailored sleep improvement programs for older adults.

Subjective cognitive decline and self‐reported sleep problems: The SCIENCe project

“…1 A growing body of evidence suggests that sleep problems are associated with cognitive impairment and progression to Alzheimer's disease (AD) dementia. 2,3 Sleep disturbances are common in patients with AD dementia; among two-thirds of AD dementia patients report sleep problems, and it is associated with poorer daily functioning. 4 Sleep disturbances have even been suggested as an early symptom of AD.…”

“…There were differences in total sleep time and sleep efficiency between the any sleep problem (6.7 hours ± 1.2, 83 ± 14%) and no sleep problem group (7.7 hours ± 0.8, 93 ± 7%; all P < .001). There was no difference in time spent in bed (CES-D median [interquartile range (IQR)]: 10[5][6][7][8][9][10][11][12][13][14][15][16] vs. 4[2][3][4][5][6][7]) and anxiety [HADS-A] 5[2][3][4][5][6][7][8][9][10] vs. 2 [0.) than those without sleep problems.…”

Examining sleep deficiency and disturbance and their risk for incident dementia and all-cause mortality in older adults across 5 years in the United States

“…Both sleep disturbances and abnormal sleep duration, although both often modifiable, are associated with the development and progression of Alzheimer’s disease [ 2 ]. Furthermore, recent work suggests that older adults (above age 65) who report signs of good sleep health (i.e., reports of waking and feeling refreshed) demonstrate better cognitive function [ 3 ], which may buffer against the development of Alzheimer’s disease and dementia. According to the National Sleep Foundation, there is more sleep disturbance reported among older adults than any other age group [ 4 ].…”

Insomnia symptoms, fatigue, and future job exit in American older adults

“…Insomnia symptoms are prevalent nocturnal complaints in older adults that influence different aspects of life. Difficulty falling asleep during the night (initial insomnia type) has been found in older adults to predict depressive cases, 42 persistent severe fatigue, 10 and decreased cognitive function 43 and increased risk for all‐cause mortality after 4–19 years of follow‐up 44 . Related to occupational functioning, our study found that older workers who reported difficulty falling asleep at the beginning of the study were 1.29 times at increased odds to retire from the labor force.…”