Association between rest-activity rhythm and cognitive function in the elderly: The U.S. National Health and Nutrition Examination Survey, 2011-2014

Abstract

BackgroundCircadian rhythm plays an essential role in various physiological and pathological processes related to cognitive function. The rest-activity rhythm (RAR) is one of the most prominent outputs of the circadian system. However, little is known about the relationships between RAR and different domains of cognitive function in older adults. The purpose of this study was to examine the relationships between RAR and various fields of cognitive function in older Americans.MethodsThis study included a total of 2090 older adults ≥ 60 years old from the National Health and Nutrition Examination Survey (NHANES) in 2011-2014. RAR parameters were derived from accelerometer recordings. Cognitive function was assessed using the word learning subtest developed by the Consortium to Establish a Registry for Alzheimer’s disease (CERAD W-L), the Animal Fluency Test (AFT) and the Digital Symbol Substitution Test (DSST). Linear regression was used to determine the relationships between RAR parameters (IS, IV, RA, L5, M10) and cognitive function scores (CERAD W-L, AFT, DSST).ResultsAfter adjusting for potential confounders, lower IS and M10 were associated with lower CERAD W-L scores (P=0.033 and P=0.002, respectively). Weaker RA and higher L5 were associated with lower AFT scores (P<0.001 and P=0.001, respectively). And lower IS, RA, and higher L5 were associated with lower DSST scores (P=0.019, P<0.001 and P<0.001, respectively). In addition, the results of sensitivity analysis were similar to those of our main analyses. The main correlation results between the RAR indicators and cognitive function were robust.ConclusionsThis study suggested that the weakened and/or disrupted RAR was associated with cognitive decline in different domains in Americans over the age of 60.

Associations between circadian alignment and cognitive functioning in a nationally representative sample of older adults

“…Our results regarding DSSS are also supported by literature regarding the cognitive effects of circadian disruption in those subjected to jet lag and nightshift schedules 7 , 8 , 11 , 12 . Overall, these studies along with ours elucidate the importance of normal sleep–wake schedules that are more strongly aligned with light and dark cues from the environment for better cognition 11 , 12 , 27 , 33 .…”

“…Sun et al, also using the NHANES data, investigated the relationships between rest-activity rhythm metrics and cognitive function in the elderly population. Consolidated rest-activity rhythms were significantly associated with lower cognitive scores across different domains 33 . These results are consistent with the associations found in our analysis, which established that phasor magnitude as a measure of circadian alignment is an important predictor of cognitive functioning.…”

Associations of Circadian Rest-Activity Rhythms With Affect and Cognition in Community-Dwelling Stroke Survivors: An Ambulatory Assessment Study

“…For example, bright light therapy is a well-established circadian intervention that has demonstrated success in strengthening the circadian rhythm to improve rhythm stability, timing, and robustness. 58 It has been shown to reduce cognitive decline 58 and prevent affective disorders. 59 Establishing a structured daily routine and wake-sleep schedule can help to regulate the times for daytime activities and sleep.…”

Selected routine laboratory tests in the clinical assessment of patients with obstructive sleep apnea

“…According to studies performed on animal models, hypoxia induces glycolysis and glycogenolysis with consequent elevation of blood glucose concentration [66]. There is correlation between AHI and glycaemic variability [67]. According to Saito et al, the glycaemic variability is more dependent on the time during sleep spent in hypoxemia (SpO2<90%), rather than on AHI [68].…”