Reference
Tighe CA, Brindle RC, Stahl ST, Wallace ML, Bramoweth AD, Forman DE, Buysse DJ. Multidimensional Sleep Health and Physical Functioning in Older Adults. Gerontol Geriatr Med. 2021 May 20;7:23337214211016222. doi: 10.1177/23337214211016222. PMID: 34095350; PMCID: PMC8142238.
At a glance
The new paradigm of multidimensional sleep health has aroused the interest of the scientific community in various fields, including aging. The purpose of this analysis was to examine the association between sleep health and physical functioning in older adults. To do this, physical functioning was assessed using objective parameters such as gait speed, grip strength and lower limb strength. Sleep health was conceptualized as a “multidimensional model”, which included the following factors: sleep times, regularity of sleep times, quality of sleep, daytime alertness, sleep efficiency and duration of sleep. The findings of this study suggest that multidimensional sleep health may contribute to physical functioning in older adults.
The context
One of the most significant challenges for contemporary society is the aging of the population. This demographic revolution has led to a growing interest in so-called “positive” or “successful aging”. Such aging is determined by the sharing of various factors, including: a low risk of disease and related disability, maintenance of high cognitive and physical capabilities, and active participation in society. With this perspective, sleep health is one of the factors that can contribute to physical functioning. The approach to sleep through a multidimensional view describes an individual’s experience of sleep-wake behavior more comprehensively than the evaluation of single aspects. Indeed, there may be a disturbance in the domain of sleep health, while the other domains remain unchanged.
Several studies in the literature have linked “multidimensional sleep health” with cardio-metabolic morbidity, all-cause mortality, and cardiovascular mortality. Moreover, one study has linked improved multidimensional sleep health to better physical functioning. That study only uses self-reported measures, however, which by definition are subjective. The purpose of this analysis was to evaluate, through objective measures, the existence of an association between multidimensional sleep health and physical performance in an elderly population.
Characteristics of the study
The authors analyzed data from two longitudinal studies in the United States (MIDUS 2 e MIDUS Refresher), which included 158 adults aged 65 years or more. All study participants underwent anamnestic interviews, self-administered questionnaires, and physical exams. Physical functioning was assessed using the following measures: gait speed during a 50-foot timed walk, lower extremity strength via chair stand test (consisting of 5 repetitions of stands-up from a chair), and grip strength via hand-held dynamometers. Data relating to the domains of sleep health were obtained through sleep diaries and wrist actigraphy over a period of one week. Composite scores of multidimensional sleep health were then derived. Data were adjusted for age, sex, race, body mass index (BMI), depressive symptoms and comorbid symptoms / conditions and then correlated to parameters of sleep health.
Results
Most of the sample (65.8%) had good sleep health on at least four of the six considered domains (sleep times, regularity of sleep times, quality of sleep, daytime alertness, sleep efficiency and duration of sleep), suggesting a relatively high level of sleep health overall. Multidimensional sleep health was significantly related to gait speed (higher levels of sleep health were associated with faster gait speed), but not to measures of lower limb extremity strength or grip strength. In particular, it was observed that the domains of sleep efficiency and sleep duration were those mainly involved in determining the speed of gait.
Study limitations
What’s new
The results of this study conservatively suggest that multidimensional sleep health may be a determinant of physical functioning in the elderly.
The prospects
These data represent a foundation on which to better define the relationship between sleep health and physical functioning, which is likely multifactorial and bidirectional.
Moreover, intervention studies could help to evaluate whether multidimensional sleep health is modifiable. If so, further assessment could help explain whether improved multidimensional sleep health might favorably impact physical performances and, ultimately, promote healthy aging.
Edited by Francesca Boarda
