The Association Between Sleep Duration and Hand Grip Strength in Community-Dwelling Older Adults: The Yilan Study, Taiwan

Prevalence, dimensions, and correlates of excessive daytime sleepiness in community-dwelling older adults: the Yilan study, Taiwan

BACKGROUND

Daytime sleepiness is an important health problem. However, the dimensionality of the Epworth Sleepiness Scale (ESS) in older adults remains unclear. This study aimed to determine the prevalence of ESS-defined excessive daytime sleepiness in older adults. Furthermore, the dimensionality of ESS and its respective correlates were also compared.

MATERIALS AND METHODS

This is a community-based survey in which community-dwelling older adults aged ≥ 65 years participated. Excessive daytime sleepiness was assessed using the ESS and was defined as an ESS score of > 10. Exploratory factor analysis was performed to identify the ESS factors. Multiple logistic regression analysis was used to examine the independent correlates of the ESS-defined and factor-specific correlates of excessive daytime sleepiness.

RESULTS

In total, 3978 older adults participated in this study. The mean age was 76.6 ± 6.7 years, with 53.8% ≥ 75 years, and 57.1% were female. The prevalence of ESS-defined excessive daytime sleepiness was 16.0%. An exploratory factor analysis revealed two factors in the ESS, which were designated as 'passive' and 'active' according to the soporific levels of ESS items loaded in each factor. Multiple logistic regression showed that male, illiteracy, depression, disability, short sleep duration and no exposure to hypnotics were risk indicators for ESS-defined excessive daytime sleepiness. However, the correlates for passive and active factor-defined excessive daytime sleepiness differ in pattern, especially in variables related to education, exercise, mental health, and sleep.

CONCLUSIONS

The prevalence of ESS-defined excessive daytime sleepiness is high, and its correlates vary among older adults. This study also suggests a dual ESS structure in community-dwelling older adults.

Association of sleep quality with physical and psychological health indicators in overweight and obese rural Indians

Objective

To measure the association of sleep quality with physical (i.e., grip strength, functional mobility, balance) and psychological (depression, anxiety) health indicators in an overweight/obese population.

Methods

Baseline data of 2337 participants (1382 overweight/obese and 955 normal weight) from an aging cohort in rural southern India (CBR-SANSCOG) was analyzed retrospectively. Assessment tools included the Pittsburgh Sleep Quality Index (PSQI) for sleep quality, dynamometry for Hand Grip Strength (HGS), Timed Up-and-Go (TUG) for functional mobility, Chair Stand Test (CST) for lower limb strength, Geriatric Depression scale (GDS-30) for depressive symptoms and Generalized Anxiety Disorder scale (GAD-7) for anxiety symptoms. Linear regression models, adjusted for known confounders, were used to examine the association of sleep quality with the health parameters in overweight/obese and normal-weight groups.

Results

In the fully adjusted model, higher global PSQI score was associated with higher TUG time (β = 0.06, 95 % CI: 0.004,0.12), higher scores on GDS (β = 1.08, 95 % CI: 0.96,1.20) and GAD (β = 0.71, 95 % CI: 0.62,0.79), and lower scores on CST (β = -0.12, 95 % CI: -0.19,-0.06) in overweight/obese individuals. The sleep disturbance sub-component of PSQI was associated with most of the physical (TUG, CST) and psychological (GDS and GAD) health indicators. Sleep duration and use of sleep medication showed no significant association with any of the health indicators.

Conclusion

The concurrent presence of poor sleep quality and overweight/obesity could worsen physical and psychological health in middle-aged and older adults. We highlight the importance of early detection and timely management of sleep problems in this population to reduce physical and psychological morbidities.

Lower motor performance is linked with poor sleep quality, depressive symptoms, and grey matter volume alterations

Motor performance (MP) is essential for functional independence and well-being, particularly in later life. However, the relationship between behavioural aspects such as sleep quality and depressive symptoms, which contribute to MP, and the underlying structural brain substrates of their interplay remains unclear. This study used three population-based cohorts of younger and older adults (n=1,950) from the Human Connectome Project-Young Adult (HCP-YA), HCP-Aging (HCP-A), and enhanced Nathan Kline Institute-Rockland sample (eNKI-RS). Several canonical correlation analyses were computed within a machine learning framework to assess the associations between each of the three domains (sleep quality, depressive symptoms, grey matter volume (GMV)) and MP. The HCP-YA analyses showed progressively stronger associations between MP and each domain: depressive symptoms (unexpectedly positive, r=0.13, SD=0.06), sleep quality (r=0.17, SD=0.05), and GMV (r=0.19, SD=0.06). Combining sleep and depressive symptoms significantly improved the canonical correlations (r=0.25, SD=0.05), while the addition of GMV exhibited no further increase (r=0.23, SD=0.06). In young adults, better sleep quality, mild depressive symptoms, and GMV of several brain regions were associated with better MP. This was conceptually replicated in young adults from the eNKI-RS cohort. In HCP-Aging, better sleep quality, fewer depressive symptoms, and increased GMV were associated with MP. Robust multivariate associations were observed between sleep quality, depressive symptoms and GMV with MP, as well as age-related variations in these factors. Future studies should further explore these associations and consider interventions targeting sleep and mental health to test the potential effects on MP across the lifespan.

Identifying characteristics and clinical conditions associated with hand grip strength in adults: the Project Baseline Health Study

Low hand grip strength (HGS) is associated with several conditions, but its value outside of the older adult population is unclear. We sought to identify the most salient factors associated with HGS from an extensive list of candidate variables while stratifying by age and sex. We used data from the initial visit from the Project Baseline Health Study (N = 2502) which captured detailed demographic, occupational, social, lifestyle, and clinical data. We applied MI-LASSO using group methods to determine variables most associated with HGS out of 175 candidate variables. We performed analyses separately for sex and age (< 65 vs. ≥ 65 years). Race was associated with HGS to varying degrees across groups. Osteoporosis and osteopenia were negatively associated with HGS in female study participants. Immune cell counts were negatively associated with HGS for male participants ≥ 65 (neutrophils) and female participants (≥ 65, monocytes; < 65, lymphocytes). Most findings were age and/or sex group-specific; few were common across all groups. Several of the variables associated with HGS in each group were novel, while others corroborate previous research. Our results support HGS as a useful indicator of a variety of clinical characteristics; however, its utility varies by age and sex.

The differential pattern of associations between nighttime sleep disturbances with dimensions of daytime sleepiness in community-dwelling older adults, the Yilan study, Taiwan

BACKGROUND

The association between nighttime sleep disturbance and daytime sleepiness remains unclear. This study aimed to examine the relationships between various domains of nighttime sleep disturbance, daytime sleepiness, and their specific dimensions.

METHODS

This was a community-based cross-sectional study. The participants were adults aged 65 years and older from Yilan City, Taiwan. Daytime sleepiness (DS) was defined using the Epworth Sleepiness Scale (ESS) with scores ≥ 11. The ESS dimensions were further examined using exploratory factor analysis. The highest 15% factor scores for each factor were defined as factor-specific DS. Various domains of nighttime sleep disturbance were assessed using the Pittsburgh Sleep Quality Index. Logistic regression analysis was used to examine the independent relationships among various nighttime sleep disturbances, ESS, and its dimensions.

RESULTS

Of the 2585 participants, a total of 59.0% were women. Two factors were identified by exploratory factor analysis and were designated as 'passive factor' and 'active factor'. Multiple logistic regression analyses elucidated that short sleep duration was a common risk indicator for ESS-defined (odds ratio (OR): 2.01; 95% confidence interval (CI): 1.43-2.83), passive factor-defined (OR: 2.23, 95% CI: 1.65-3.00), and active factor-defined DS (OR: 1.47, 95% CI: 1.07-2.00). Hypnotic use was associated with a lower risk of both ESS-defined (OR: 0.66, 95% CI: 0.47-0.92) and passive factor-defined DS (OR:0.69, 95% CI: 0.52-0.92). Bathroom use (OR: 1.41, 95% CI: 1.04-1.91), coughing or snoring (OR: 2.14, 95% CI: 1.01-4.56), and sleep efficiency (OR: 0.42; 95% CI: 0.31-0.57) were uniquely associated with active factor-defined DS.

CONCLUSION

Two factors were identified in the ESS, revealing factor-specific correlates of DS. Specifically, ESS- and passive factor-defined DS shared similar correlates. In contrast, some correlates seem unique to active-factor-defined DS.

Different dimensions of daytime sleepiness predicted mortality in older adults: Sex and muscle power-specific risk in Yilan Study, Taiwan

OBJECTIVES

This study aimed to investigate the relationship between daytime sleepiness and mortality risk among older adults. The moderating effects of sex and physical function were examined.

METHODS

This 9-year follow-up study was conducted with community-dwelling individuals aged ≥65 years. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). Exploratory factor analysis (EFA) was used to examine the ESS factors. Handgrip strength was measured to assess physical function, and the highest quartile was defined as good muscle power. Cox regression analysis was used to estimate the 9-year all-cause mortality risk. The interaction terms were examined to evaluate their moderating effect.

RESULTS

In total, 2588 individuals participated in the study. The EFA explored two factors: the passive factor (PF) and the active factor (AF). After controlling for various covariates, the cutoff-defined daytime sleepiness (ESS≥11), total raw scores, and factor scores of the ESS all failed to predict mortality risk. The 3-way interaction terms showed statistical significance in terms of [sex × PF × muscle power (p = 0.03)] but not for [sex × AF × muscle power (p = 0.11)]. Specifically, PF predicted mortality risk in women with good muscle power (hazard ratio (HR): 1.48; 95 % confidence interval (CI): 1.04-2.10), which is female-specific. In contrast, AF predicted mortality risk only in men with good muscle power (HR: 1.35; 95 % CI: 1.02-1.78).

CONCLUSIONS

The ESS-measured daytime sleepiness in older adults is multidimensional. The mortality risk for each dimension was determined based on sex and physical function.

Handgrip strength is associated with mortality in community-dwelling older adults: the Yilan cohort study, Taiwan

INTRODUCTION

Hand grip strength (HGS) is one of the methods to help early identification of physical frailty and sarcopenia, the major concerns in the aging societies. It is also crucial to evaluate its impact on mortality. However, the available evidence regarding such impact among specific age cohorts (65 to 74 years and above) is limited. This study tried to investigate the relationship between HGS and mortality among specific cohorts of the community-dwelling older individuals in Yilan, Taiwan.

METHODS

A seven-year longitudinal follow-up study was conducted involving 2,468 community-dwelling older individuals in Yilan. The participants were divided into two groups based on their quartiles of hand grip strength: with poor HGS and with good HGS. The association between HGS and mortality was examined using Cox proportional hazards models.

RESULTS

The analysis revealed that age, HGS, gender, medical history of cardiovascular diseases, body mass index, and wrist-hip ratio had significant impacts on seven-year survival. Specifically, individuals with poor HGS exhibited increased mortality, with an adjusted hazard ratio (HR) of 1.87 (95% CI: 1.52-2.30). Furthermore, the adverse effect of poor HGS on mortality was more pronounced in males aged 65-74 years (adjusted HR 4.12, 95% CI: 2.16-7.84), females aged 75 years or older (2.09, 1.43-3.04) and males aged 75 years or older (1.49, 1.07-2.07).

CONCLUSION

Poor hand grip strength is an independent risk factor for mid-term mortality among community-dwelling older individuals in Yilan. The assessment of HGS can serve as a valuable tool in identifying older individuals at higher risk of death.

Sleep duration and depressive symptoms in Chinese middle-aged and older adults: The moderating effects of grip strength

BACKGROUND

Evidence on the combined effect of sleep duration and grip strength on depressive symptoms is scarce. This study aimed to explore the moderating effect of grip strength on the association between sleep duration and depressive symptoms in a large cohort of middle-aged and older adults.

METHOD

Data were extracted from the China Health and Retirement Longitudinal Study (CHARLS) 2011-2018 wave. Grip strength and sleep duration were assessed by dynamometer and self-report, respectively. Depressive symptoms were determined by the Centre for Epidemiological Studies Depression scale (CESD-10). Multivariable cox regression model was used to explore the associations between sleep duration, and depressive symptoms, and assess moderation by grip strength.

RESULTS

A total of 4337 participants aged 57.0 ± 8.1 years (45.1 % females) were included in this study. During the 7-year follow up period, 1508 participants developed depressive symptoms. Short sleep duration (<6 h/d) was significantly associated with an increased risk of depressive symptoms [Hazard ratio (HR):1.24, 95 % confidence interval (CI):1.09, 1.40)]. This association remained in individuals with the low (HR:1.22, 95%CI:1.00, 1.49) and middle grip strength (HR:1.32, 95%CI: 1.07, 1.63), but attenuated in individuals with high grip strength (HR:1.11, 95%CI: 0.86, 1.43).

CONCLUSIONS

High grip strength mitigated the association between short sleep duration and higher risk of depressive symptoms. Thus, improving sleep duration and strengthening muscle strength are recommended to prevent depressive symptoms in middle-aged and older adults.

Is There a Relationship Between Waking Up from Sleep and the Onset of Testicular Torsion?

Testicular torsion is a serious urologic emergency that can present with unusual or atypical history and examination. Classical pain from testicular torsion is of sudden onset, significantly severe, and is accompanied by nausea and vomiting. However, in some patients, the initial scrotal pain appears to considerably subside within the next few hours. In others, testicular torsion tends to occur while sleeping, and many patients recount a history of being woken up from sleep by intense pain. Furthermore, some patients in this subset can resume normal activities and even sleep through the night with little or no discomfort, without a perceived need for pain medications. Other patients initially experience mild pain, which worsens over time. Consequently, these patients are less likely to be evaluated immediately. In view of these atypical cases, the question remains unanswered regarding sleep as a predisposing factor for testicular torsion. This narrative review focuses on exploring the association between sleep and testicular torsion.

Reduced grip strength potentially indicates depression: Investigating multicontinental databases

BACKGROUND

Multi-national studies in the association between handgrip strength and depression in middle and older aged adults are limited. Hence, Brazil, China, Europe, Korea, United Kingdom (UK) and United States (US) datasets were utilized to investigate this association.

METHODS

A cross-sectional study was conducted with 51,285 participants aged >45 years. Handgrip strength scores were divided into quartiles, groups 1 (highest) to 4 (lowest) in each database, and depression measures converted to binary scores.

RESULTS

Males in China and UK reported higher adjusted odds ratios (aORs) of depression for groups 2, 3, and 4 than for group 1. Brazil, US, and Korea reported greater aORs in groups 3 and 4 whereas Europe demonstrated increased aORs for group 4 only. Among females, China, Brazil, US, and Korea showed high aORs across all groups, while UK and Europe reported increased aORs for group 4 only. Highest ORs were reported from Korea in group 4 for males (aOR: 3·09; 95 % CI: 2·15-4·43; p < 0·001) and females (aOR: 3·74; 95 % CI: 2·78-5·03; p < 0·001). When removing the regional factor, aORs were higher in lower groups, with the highest reported from group 4 for males (aOR: 2·32; 95 % CI: 2·09-2·58; p < 0·001) and females (aOR: 2·11; 95 % CI: 1·95-2·29; p < 0·001).

LIMITATIONS

Being a cross-sectional study, the results were not able to establish the causal direction between handgrip strength and depression.

CONCLUSION

Lower handgrip strength was associated with an increased likelihood of depression. Early assessment of handgrip strength may identify populations at-risk for depression among middle and older aged adults.

Association between Sleep Duration and Grip Strength in U.S. Older Adults: An NHANES Analysis (2011-2014)

Handgrip strength has been shown an indispensable biomarker for older adults. Furthermore, the association between sleep duration and grip strength in special populations (e.g., type 2 diabetics) has been previously documented. However, the association between sleep duration and grip strength has been less studied in older adults and the dose-response relationship is unclear. Therefore, we drew 1881 participants aged 60 years and older from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 to explore their association and the dose-response relationship. Sleep duration was obtained through self-report. Grip strength data were obtained through a grip test using a handgrip dynamometer and divided into two categories: low grip strength and normal grip strength. Thus, dichotomized grip strength was used as a dependent variable. Poisson regression and restricted cubic spline were used for the main part of the analysis. We found that long sleep duration (≥9 h) was associated with a higher prevalence of low grip strength than the normal sleep duration (7-<9 h) group (IRR: 1.38, 95% CI: 1.12-1.69). Moreover, the gender-stratified analysis did not change the original results. This association was particularly pronounced and further strengthened among participants with normal weight (BMI < 25) (IRR: 2.30, 95% CI: 1.64-3.22) and participants aged 60-70 (IRR: 1.76, 95% CI: 1.40-2.22). In addition, with the increase in sleep duration, the multivariate-adjusted IRRs of low grip strength had a general downward trend at first, followed by a brief period of stability, and then presented an upward trend (p-value for non-linearity = 0.001). According to this study, we found that older adults who had long sleep duration had a higher risk of low grip strength. Muscle insulin utilization and muscle glucose metabolism are closely related to grip strength, so our research emphasizes the importance of maintaining normal sleep duration in older adults and suggests that older adults who sleep for a long period should pay more attention to their muscle health.

Association between Sleep Duration and Hand Grip Strength among COPD Patients

This study aimed to evaluate the association between night-time sleep duration and hand grip strength (HGS) among patients with chronic obstructive pulmonary disease (COPD). Participants aged ≥45 years were included in a nationally representative investigation clinical study in 2015. HGS was measured using dynamometers. The data on night-time sleep duration, sociodemographic information, and health-related variables were systematically collected. For analysis, sleep duration was categorized as <5 h, 5-7 h, 7 h, 7-9 h, and >9 h. Multivariable linear regression models were used to determine the possible association between the night-time sleep duration and HGS. Our results indicated that the shortest (<5 h) or the longest sleep duration (>9 h) was relevant to high risk of weaker HGS in females. In males, the shortest (<5 h) sleep duration was correlated to lower HGS. Thus, our findings clearly suggest that health care providers should focus on the potential influence of sleep duration on HGS among COPD patients.

Association between Sleep Duration and Physical Fitness in Children Aged 3-6 Years: A Cross-Sectional Study from China

Aim: To explore associations between sleep duration and physical fitness (PF) of children aged 3−6 years. Methods: This study investigated the sleep duration and PF data of children aged 3−6 years by stratified random sampling. The restricted cubic spline model and binary logistic regression analysis were mainly used for the empirical analysis of the correlation effect between sleep duration and PF. The final data had a total of 21,857 children, of which 11,245 (51.45%) were boys and 10,612 (48.55%) were girls. Results: The PF level of the children in this study showed a relatively positive level (pass rate = 93.6%), and 19.7% of them had abnormal sleep duration; the results of the restricted cubic spline showed an inverted U-shaped association between the level of PF and the risk of abnormal sleep duration (X2 = 28.13, p < 0.0001). The results of logistic regression analysis showed that children with abnormal sleep duration were more likely to have a low PF, body morphology and motor ability levels at an OR (95% CI) of 1.077 (1.023−1.133), 1.077 (1.016−1.142) and 1.035 (1.08−1.062), respectively. The results of the bias correlation analysis showed varying degrees of correlation between sleep duration and various components of children’s PF. Conclusion: Insufficient or excessive amounts of sleep were significantly associated with PF in children, with abnormal sleep duration leading to reduced levels of PF and its components.

Sleep Duration and Frailty Risk among Older Adults: Evidence from a Retrospective, Population-Based Cohort Study

OBJECTIVES

Frailty and sleep duration complaints are both prevalent and often coexist among older adults. The purpose of this study was to examine the prospective association between sleep duration and frailty risk in a nationally representative cohort study.

DESIGN

Prospective cohort study, ten-year follow-up.

SETTING

Community-based setting in 23 provinces of China.

PARTICIPANTS

A total of 7623 older adults age 65 and over without frailty at baseline were included in the analysis.

MEASUREMENTS

The participants were divided into three groups according to self-reported sleep duration: short (≤6 hours per day), middle (>6 but <10 hours per day) and long (≥10 hours per day). Frailty was measured according to the accumulation of health deficits by the construction of a frailty index of 38 items with 0.25 as the cutoff. A Cox proportional hazard model, a competing risk model and a generalized estimating equation (GEE) model with multiple adjustments were performed to evaluate the association between sleep duration and frailty risk.

RESULTS

During a median follow-up period of 4.4 years (IQR 2.9-9.0), 2531 (33.2%) individuals developed frailty. Compared with participants with middle sleep duration, the risk of frailty was increased among participants with long sleep duration (HR 1.26, 95% CI 1.14-1.38) in the fully adjusted Cox proportional hazard model. However, short sleep duration was insignificantly associated with frailty risk. The competing risk model and the GEE model yielded similar results.

CONCLUSION

Long sleep duration is significantly associated with frailty incidence among older adults even after adjustment for confounding factors. This study provides reinforcing longitudinal evidence for the need to design sleep quality improvement interventions in health care programs to prevent frailty among older adults.

Sleep duration and progression to sarcopenia in Japanese community-dwelling older adults: a 4 year longitudinal study

BACKGROUND

Identifying factors that contribute to the development of sarcopenia in older adults is a public health priority. Although several studies have examined the association between sleep duration and sarcopenia, additional evidence is needed to reveal the causality of this association, especially from a longitudinal study. The purpose of the present study was to examine whether sleep duration was associated with the progression to sarcopenia and its subcomponents among community-dwelling older adults in Japan.

METHODS

A total of 3918 older community-dwelling people (mean age: 73.2 ± 6.0 years, 51.8% female) included in the National Center for Geriatrics and Gerontology Study of Geriatric Syndromes were analysed. Sleep duration was assessed using a self-reported questionnaire. Logistic regression analysis was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of progression of sarcopenia at Wave 2 (4 years later), according to the three categories of sleep duration [short: ≤6.0 h, medium: 6.1-8.9 h (control), & long: ≥9.0 h)] at Wave 1.

RESULTS

The numbers in each group in the second wave among the total sample were as follows: short 403 (10.3%), medium 2877 (73.4%), and long 638 (16.3%). Significant associations with the progression of sarcopenia were found in the long sleep duration group compared with the medium one, even after adjustment for other covariates (OR 1.66, 95% CI: 1.02-2.69, P = 0.040). Long sleep duration was significantly associated with slow gait (OR: 1.55, 95% CI: 1.17-2.06, P = 0.002) and low grip strength (OR: 1.34, 95% CI: 1.00-1.78, P = 0.047) but was not associated with low muscle mass (OR: 1.33, 95% CI: 0.74-2.38, P = 0.343).

CONCLUSIONS

This study revealed that long sleep duration was associated with an increased risk of progression to sarcopenia among older adults.

Using hand grip strength to detect slow walking speed in older adults: the Yilan study

Background

Walking speed is an important health indicator in older adults, although its measurement can be challenging because of the functional decline due to aging and limited environment. The aim of this study was to examine whether hand grip strength can be a useful proxy for detecting slow walking speed in this population.

Methods

A cross-sectional study was conducted using the cohort from the Yilan Study in Taiwan. Community-dwelling older adults aged 65 years and older were included. Slow walking speed was defined as a 6-meter walking speed < 1.0 m/s, according to the 2019 Asian Working Group for Sarcopenia diagnostic criteria. Stepwise multiple linear regression was used to determine the most significant variables associated with walking speed. Receiver operating characteristic analysis was used to determine the optimal cutoff values for hand grip strength in detecting slow walking speed.

Results

A total of 301 participants with an average age of 73.9 ± 6.8 years were included; 55.1 % participants were women. In stepwise multiple linear regression analysis that included various variables, hand grip strength was found to be the most explainable factor associated with walking speed among all participants and among participants of each sex. The optimal cutoff values for hand grip strength in the detection of slow walking speed were 19.73 kg for all participants (sensitivity: 55 %, specificity: 83 %, area under the curve: 0.74, accuracy: 66.9 %), 35.10 kg for men (sensitivity: 92 %, specificity: 42 %, area under the curve: 0.70, accuracy: 66.4 %), and 17.93 kg for women (sensitivity: 62 %, specificity: 80 %, area under the curve: 0.76, accuracy: 67.9 %).

Conclusions

Hand grip strength was found to be a useful proxy for the identification of slow walking speed in older adults.

Association of Sleep and β-Amyloid Pathology Among Older Cognitively Unimpaired Adults

IMPORTANCE

Disrupted sleep commonly occurs with progressing neurodegenerative disease. Large, well-characterized neuroimaging studies of cognitively unimpaired adults are warranted to clarify the magnitude and onset of the association between sleep and emerging β-amyloid (Aβ) pathology.

OBJECTIVE

To evaluate the associations between daytime and nighttime sleep duration with regional Aβ pathology in older cognitively unimpaired adults.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, screening data were collected between April 1, 2014, and December 31, 2017, from healthy, cognitively unimpaired adults 65 to 85 years of age who underwent florbetapir F 18 positron emission tomography (PET), had APOE genotype information, scored between 25 and 30 on the Mini-Mental State Examination, and had a Clinical Dementia Rating of 0 for the Anti-Amyloid Treatment in Asymptomatic Alzheimer Disease (A4) Study. Data analysis was performed from December 1, 2019, to May 10, 2021.

EXPOSURES

Self-reported daytime and nighttime sleep duration.

MAIN OUTCOMES AND MEASURES

Regional Aβ pathology, measured by florbetapir PET standardized uptake value ratio.

RESULTS

Amyloid PET and sleep duration information was acquired on 4425 cognitively unimpaired participants (mean [SD] age, 71.3 [4.7] years; 2628 [59.4%] female; 1509 [34.1%] tested Aβ positive). Each additional hour of nighttime sleep was associated with a 0.005 reduction of global Aβ standardized uptake value ratio (F1, 4419 = 5.0; P = .03), a 0.009 reduction of medial orbitofrontal Aβ (F1, 4419 = 17.4; P < .001), and a 0.011 reduction of anterior cingulate Aβ (F1, 4419 = 15.9; P < .001). When restricting analyses to participants who tested Aβ negative, nighttime sleep was associated with a 0.006 reduction of medial orbitofrontal Aβ (F1,2910 = 16.9; P < .001) and a 0.005 reduction of anterior cingulate Aβ (F1,2910 = 7.6; P = .03). Daytime sleep was associated with a 0.013 increase of precuneus Aβ (F1,2910 = 7.3; P = .03) and a 0.024 increase of posterior cingulate Aβ (F1,2910 = 14.2; P = .001) in participants who tested Aβ negative.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, the increased risk of Aβ deposition with reduced nighttime sleep duration occurred early, before cognitive impairment or significant Aβ deposition. Daytime sleep may be associated with an increase in risk for early Aβ accumulation and did not appear to be corrective for loss of nighttime sleep, demonstrating a circadian rhythm dependence of sleep in preventing Aβ accumulation. Treatments that improve sleep may reduce early Aβ accumulation and aid in delaying the onset of cognitive dysfunction associated with early Alzheimer disease.

Daytime activity and sleep are associated with motor function in older intensive care unit survivors

BACKGROUND

Hospitalized older intensive care unit (ICU) survivors are often inactive and experience sleep disturbances.

OBJECTIVE

We explored associations between post-ICU activity, sleep/rest, and motor function among hospitalized older ICU survivors.

METHODS

We enrolled 30 older ICU survivors, ages 65 and older, within 24-48 h of ICU discharge. Actigraphy measured post-ICU activity and sleep/rest. Selected measures from the National Institutes of Health Toolbox Motor Battery assessed grip strength and dexterity. Multivariate regression examined associations between post-ICU activity, sleep/rest, and motor function, adjusting for covariates.

RESULTS

Lower daytime activity (β = 0.258, p = .035) and greater daytime sleep/rest (β = -0.295, p = .022) were associated with worse grip strength. Lower daytime activity (β = -0.376, p = .037) and greater daytime sleep/rest (β = 0.409, p = .026) were associated with worse dexterity.

CONCLUSION

Post-ICU inactivity and prolonged rest periods are associated with worse motor function in hospitalized older ICU survivors.

Correlation between Handgrip Strength and Depression in Older Adults-A Systematic Review and a Meta-Analysis

Background: Depression remains an important health problem among older adults and it may be correlated with the deterioration of physical fitness, whose chief indicator is hand grip strength (HGS). The aim of the study was to investigate the relationship between depression and HGS among older populations using the available literature. Methods: PubMed, Web of Science and Science Direct databases were searched. The inclusion criteria were as follows: written in English and published after 2009, subject age: ≥60 years, HGS measured using a hand dynamometer, assessment of the depressive symptoms using a validated tool. The following articles were excluded: studies conducted among institutionalized subjects and/or populations with a specific disease. Results: The total combined effect of 33 results presented in 16 studies included in the meta-analysis, converted to the correlation coefficient, was OEr = −0.148 (SE = 0.030, 95%CI: −0.206–−0.091), indicating a weak, negative correlation between HGS and depressive symptoms. Conclusions: The review of the literature and the meta-analysis demonstrated a relationship between low muscle strength and intensified depressive symptoms in older populations. Bearing in mind that depression is often unrecognized or underdiagnosed among older patients, lowered muscle strength should be an important sign for physicians and an incentive to screen them for depression.

Associations between longitudinal trajectories of insomnia symptoms and sleep duration with objective physical function in postmenopausal women: the Study of Women's Health Across the Nation

STUDY OBJECTIVES

Examine the association between trajectories of self-reported insomnia symptoms and sleep duration over 13 years with objective physical function.

METHODS

We utilized data from 1627 Study of Women's Health Across the Nation (SWAN) participants, aged 61.9±2.7 y at the end of the 13-y follow-up. Latent class growth models identified trajectories of insomnia symptoms (trouble falling asleep, frequent night-time awakenings, and/or early-morning awakening) and sleep duration over 13 y. Physical function tests were performed at the end of the 13-y period: 40-ft walk, 4-m walk, repeated chair stand, grip strength, and balance. Multivariable regression analyses examined each physical function measure according to the insomnia symptom or sleep duration trajectory group.

RESULTS

Five insomnia symptom trajectories and two sleep duration trajectories were identified. Women with a consistently high likelihood of insomnia symptoms and women with a decreased likelihood of insomnia symptoms (i.e., improving) had slower gait speed (3.5% slower 40-ft walk [consistently high], 3.7% slower 4-m walk [improving]; each P≤.05) than those with a consistently low likelihood of insomnia symptoms. In contrast, women with a steep increase in the likelihood of insomnia symptoms over time and women with persistent insufficient sleep duration had lower odds of having a balance problem (odds ratio [OR]=0.36 and OR=0.61, respectively; each P<.02) compared to those with a consistently low likelihood of insomnia symptoms and those with persistent sufficient sleep duration, respectively.

CONCLUSION

These results suggest that women's sleep during midlife has important implications for maintaining physical function during the transition into older adulthood.

Association between objectively measured sleep duration and physical function in community-dwelling older adults

STUDY OBJECTIVES

The aim of this research was to investigate the relationships between objectively measured sleep duration and physical function in older adults.

METHODS

We recruited community-dwelling older adults aged ≥ 60 years old in Taipei City, Taiwan. Sleep duration was measured with accelerometers and recorded as the total hours of sleep per night for each participant. The following physical functions were assessed: 1) grip strength (measured by handgrip dynamometer), 2) balance (1-leg standing test), 3) lower body strength (5-timed chair stand), 4) basic mobility (timed up and go test), 5) gait speed (5-m walk test). The relationships between sleep duration and physical function outcomes were analyzed using generalized additive models, controlling for objectively measured sedentary behavior and moderate-to-vigorous physical activity, and other sociodemographic variables.

RESULTS

A total of 121 older adults (men = 28.9%; mean age = 70.0 ± 5.0 years) was included in this study. A positive association of sleep duration with grip strength was found after adjusting for covariates (P = .005). No significant associations were observed between sleep duration and the other physical function outcomes.

CONCLUSIONS

For older adults, lengthening their sleep duration may be helpful to enhance the grip strength. This result has implications for improving their health by targeting better performance in specific physical functions. Further studies of sleep duration and physical function among older adults should investigate the underlying mechanisms.

Subjective sleep quality and association with depression syndrome, chronic diseases and health-related physical fitness in the middle-aged and elderly

Background

As a complex phenomenon, sleep quality is difficult to objectively define and measure, and multiple factors related to sleep quality, such as age, lifestyle, physical activity, and physical fitness, feature prominently in older adult populations. The aim of the present study was to evaluate subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) and to associate sleep quality with health-related physical fitness factors, depressive symptoms, and the number of chronic diseases in the middle-aged and elderly.

Methods

We enrolled a total of 283 middle-aged and elderly participants from a rehabilitation clinic or health examination department. The PSQI was used to evaluate sleep quality. The health-related fitness assessment included anthropometric and physical fitness parameters. Depressive symptoms were measured with the Center for Epidemiologic Studies Depression Scale (CES-D) short form. Data were analyzed with SPSS 18.0, and descriptive statistics and logistic regression analysis were used for the analyses.

Results

Overall, 27.9% of participants in this study demonstrated bad sleepers (with a PSQI score of > 5), 10.2% of study participants frequently used sleep medication to help them fall asleep, and 6.0% reported having significant depressive symptoms (with a CES-D score of ≥10). There are two major findings: (1) depression symptoms, the number of chronic diseases, self-rated health, and arthritis were significantly associated with a poor sleep quality, and (2) the 2-min step test was associated with longer sleep latency. These results confirmed that the 2-min step was associated with a longer sleep latency among the health-related physical fitness items.

Conclusions

Our study found that depressive syndrome, chronic disease numbers, a poor self-rated health status, and arthritis were the main risk factors that influenced subjective sleep quality.

Role of physical activity and fitness on sleep in sedentary middle-aged adults: the FIT-AGEING study

The association of physical activity and fitness with sleep still remains unclear since there is a lack of studies in this field of research using objective measurements of these variables. This study aimed to investigate the association of objectively-measured sedentariness, physical activity levels, and physical fitness with sleep quantity and quality in sedentary middle-aged adults. A total of 74 volunteers (52.7% women; aged 53.7 ± 5.1) were recruited for the present study. Cardiorespiratory fitness was measured through a maximal treadmill test, and muscular strength by extension and flexion peak torque, and by the hand grip test. Physical activity and objective sleep parameters were determined through accelerometry, and subjective sleep by the Pittsburgh Sleep Quality Index (PSQI). Reduced levels of sedentariness, greater VO_2max, and greater muscular strength were positively related to improved objective sleep quantity and quality (all P ≤ 0.05). Furthermore, higher levels of overall physical activity, VO_2max, and muscular strength were related to better subjective sleep quantity and quality (all P ≤ 0.05). Reduced sedentariness and increased physical activity and fitness may be a potential prevention and/or treatment pathway to reduce sleep disturbances and, in general, to improve patients physical and psychological health for a successful aging process.

The Development of a Rapid Classification Scale for Sleep Quality in Community-Dwelling Older Adults - The Yilan Study, Taiwan

OBJECTIVE

Poor sleep quality is prevailing, deleterious, but heterogeneous in older adults. This study aimed to develop a simplified instrument to screen and classify poor sleep quality in community-dwelling older adults, by which stepped care with needs-based interventions could be implemented.

METHODS

Cohorts of adults aged 65 years and older were used to develop the Rapid Classification Scale for Sleep Quality (RCSSQ). Poor sleep quality was defined with the Pittsburgh Sleep Quality Index (PSQI). Established subgroups of poor sleep quality in the development dataset (n = 2622) were used as the criterion standard. Two independent validation datasets (n = 964 and 193, respectively) were used to examine the external validity. Questions in the PSQI were examined by the stepwise multinomial logistic regressions to determine the optimal numbers of items in the RCSSQ. On the premise of item parsimony and instrument validity, the optimal combination of reduced items was determined.

RESULTS

In the development dataset, the 4-item RCSSQ (RCSSQ-4) was the optimal predictive model. In terms of internal validity, the accuracy rates to identify PSQI-defined poor sleep quality and its subgroups in the developmental dataset by the RCSSQ-4 were 89.0% and 79.9%, respectively. Meanwhile, the RCSSQ-4 also had good external validity in the validation datasets to detect PSQI-defined poor sleep quality (accuracy rates: 89.1-90.7%). Furthermore, the profiles of PSQI component scores and comorbid conditions for the predicted subgroups in the validation dataset were comparable with the criterion standard.

CONCLUSION

The RCSSQ-4 is a valid instrument for screening and subgrouping poor sleep quality in community-dwelling older adults. The RCSSQ-4 may help guide tailored interventions under the context of stepped care in the community.

Poor sleep quality and physical performance in older adults

OBJECTIVES

This study aimed to examine the association between sleep quality and physical performance among a group of UK community-dwelling older adults, according to sex.

METHODS

Sleep quality was assessed using the Pittsburgh Sleep Quality Index. Physical performance was assessed using a short physical performance battery (SPPB), a timed up-and-go, and a hand-grip strength test.

RESULTS

Of 591 eligible study members, 401 completed the Pittsburgh Sleep Quality Index. In regression analyses, men who reported poor sleep quality were significantly more likely to have a poor SPPB score, even after adjustment for confounding factors (OR = 2.54, 95% CI 1.10-5.89, P= .03). The direction of the relationship was reversed among women, where those who reported poor sleep were less likely to have a low SPPB score (OR = 0.36, 95% CI 0.15-0.85, P = .02). Poor sleep quality was associated with poorer hand-grip strength among women (regression coefficient = -0.34 z score, 95% CI -0.64, -0.04, P = .03), but this relationship was not observed among men (regression coefficient = 0.28 z score, 95% CI -0.01, 0.57, P = .06).

CONCLUSION

We found evidence of an association between poor sleep quality and poorer physical performance in older adults, though there appear to be important sex differences.

Association between muscle strength and sleep quality and duration among middle-aged and older adults: a systematic review

PURPOSE

To examine the relationship between sleep quality and duration and muscle strength among community-dwelling middle-aged and older adults.

METHODS

A systematic review was conducted from March 2020 until May 2020. Searches were done for peer-reviewed and English-written articles reporting results of studies in PubMed, Embase, Scopus, Cochrane Library, and in article references lists. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses was used as well as the Newcastle-Ottawa Scale (NOS) to appraise the methodological quality.

RESULTS

Twenty-one cross-sectional, three prospective studies and a total of 92,363 subjects were included. The majority of the included studies are classified as "high quality". Handgrip strength is the main method of muscle strength assessment. Sleep assessment is usually conducted using subjective measures, such as validated sleep scales or self-reported questionnaires. Actigraphy, as an objective measure, is used less often. Most studies support strong evidence on the association between weak muscle strength and poor sleep quality and duration among middle-aged and older adults; whereas the results for the gender-specific association and the impact of short or long sleep duration were inconclusive.

CONCLUSION

This review has identified strong evidence on the relationship between sleep quality and duration and muscle strength among middle-aged and older adults. Health professionals should consider this relationship as a component of geriatric assessment in community practice and geriatric settings. Future rigorous research with a combination of subjective and objective measurements is needed to explore whether gender and specific sleep duration are related to muscle strength.

Associations of physical fitness and physical activity with sleep among middle-aged women

BACKGROUND

Sleep is an important component of health. Sleep disturbances increase in women as they enter menopause. Physical activity has been associated with improved sleep among older populations. The purpose of this study was to determine if physical activity and/or physical fitness are associated with sleep quantity and quality in middle-aged women.

METHODS

This study recruited 114 healthy women, aged 30-55 (43±8 y) from Saskatoon, Saskatchewan, from 2015-2019. Sleep quantity and quality were evaluated. Participants were classified on their aerobic fitness, based on estimated peak aerobic capacity, as high or low grip strength and, as active or inactive.

RESULTS

The high aerobic fitness group had a greater mean sleep duration of 7.04±1.02 h compared to the low fit group 6.61±1.00 h after adjusting for age, Body Mass Index, waist circumference and menstrual status (P=0.01). The percentage of high aerobic fitness women who felt rested was greater than low aerobic fitness women (67±6% vs. 45±7%, P=0.03), after adjusting for age, Body Mass Index, waist circumference and menstrual status. Our study found a significant difference between women with higher aerobic fitness levels getting more sleep each night and feeling more rested.

CONCLUSIONS

The continued examination of physical fitness and its relationship to sleep holds importance for women's health.

Low one-repetition-maximum knee extension is significantly associated with poor grip strength, female sex, and various aging-related syndromes

OBJECTIVE

Muscle strength in older adults is usually measured according to grip strength, which demonstrates upper muscle strength only. In this study, we used one-repetition-maximum (1-RM) knee extension as a measure of lower limb strength and assessed its relationship with grip strength and various geriatric syndromes.

METHODS

One hundred outpatients over the age of 65 years were recruited from a geriatric medicine center in India. The 1-RM knee extension was measured along with grip strength. Various geriatric conditions were measured, such as: nutrition (using the Mini Nutritional Assessment), cognition (Hindi Mental State Questionnaire), depression (5-item Geriatric Depression Scale), frailty (Fried and Rockwood models), and osteoporosis (dual-energy X-ray absorptiometry scan). Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria.

RESULTS

The mean age of participants was 72.5 years with 69% of them male. Median values of 1-RM knee extension and grip strength were 2.29 (0.5-10.0) and 17.5 (0-78), respectively. The 1-RM knee extension had moderate correlation with grip strength (r = 0.491, P < 0.001). Among demographic details, only female sex (P < 0.001) was significantly associated with lower 1-RM values. Further, after adjusting for age and sex, lower value of log10 1-RM knee extension was found to be significantly associated with malnutrition (P = 0.001), dementia (P = 0.016), depression (P = 0.047), frailty (Rockwood: P = 0.049; Fried: P = 0.011), and sarcopenia (P < 0.001).

CONCLUSION

The 1-RM knee extension has only moderate correlation with grip strength. A lower 1-RM knee extension value is significantly associated with female sex and various geriatric conditions, such as malnutrition, dementia, depression, frailty, and sarcopenia.

The associations between various sleep-wake disturbances and depression in community-dwelling older adults- the Yilan study, Taiwan

Objectives: Given the close relationship between sleep-wake disturbances and depression, an in-depth investigation of such a relationship is imperative. The present study aims at elucidating the relationship between various sleep-wake disturbances and depression in older adults and at examining the influence of co-occurring anxiety on such associations.Method: A community-based survey using the cohort from the Yilan Study in Taiwan was conducted from August 2013 to November 2016. Adults aged 65 and older were randomly selected to participate in the study. The Hospital Depression and Anxiety Scale was used to measure clinical depressive and anxiety symptoms. Insomnia and daytime sleepiness were defined through the Athens Insomnia Scale and the Epworth Sleepiness Scale, respectively. Furthermore, the use of hypnotics, subjective sleep duration and sleep-wake scheduling were evaluated. Their relationship with depression was examined through logistic regression analyses.Results: There were 2620 participants surveyed and 247 (9.4%) had depression. Before controlling for anxiety, insomnia (OR: 1.78, 95% CI: 1.23-2.55), daytime sleepiness (OR: 1.79, 95% CI: 1.27-2.53), and long sleepers (OR: 1.77, 95% CI: 1.24-2.53) have a higher likelihood for depression in the multivariable regression analysis. However, when including anxiety into the multivariable regression model, only those with daytime sleepiness and long sleepers had an elevated risk for depression. Therefore, the association between insomnia and depression turned to be statistically non-significant.Conclusion: In older adults, various sleep-wake disturbances differ in their relationship with depression. In addition, daytime sleepiness and long sleep duration were mostly characteristic of depression when co-occurring anxiety was considered.

Normative data and associated factors of hand grip strength among elderly individuals: The Yilan Study, Taiwan

Weak grip strength is associated with subsequent mortality in elderly populations. The normative data and associated factors of HGS in community-dwelling elderly Taiwanese populations require further evaluation. From February 2012 until the end of 2016, all residents of Yilan City, Taiwan aged 65 years or older were randomly selected for a population-based community health survey. A total of 2,470 older adults were enrolled in this study. The relationships between HGS and various anthropometric and sociodemographic correlates were examined. The results showed that HGS was higher in men than in women. The mean HGS exhibited a decreasing trend with advanced age in both men and women. HGS was significantly associated with height, weight, and exercise habits. The physical as well as the mental component summary measures of health-related quality of life (HRQoL) were positively associated with HGS. After HRQoL was integrated into the regression model, female sex, age, waist circumference, and diabetes mellitus were significantly negatively associated with HGS. In conclusion, HGS significantly decreased with advanced age. among community-dwelling Taiwanese elderly people, Various factors had different effects on HGS.

Subgrouping Poor Sleep Quality in Community-Dwelling Older Adults with Latent Class Analysis - The Yilan Study, Taiwan

The manifestation of older adults with poor sleep quality is heterogeneous. Using data-driven classifying methods, the study aims to subgroup community-dwelling older adults with poor sleep quality. Adults aged 65 and older participated in the Yilan study. Poor sleep quality was defined using the Pittsburgh Sleep Quality Index. Latent class analysis with the 7 subscores of the Pittsburgh Sleep Quality Index as the indicators was used to generate empirical subgroups. Differences in comorbidity patterns between subgroups were compared. A total of 2622 individuals, of which 1011 (38.6%) had Pittsburgh Sleep Quality Index -defined poor sleep quality, participated. Three groups for poor sleep quality were specified in the latent class analysis: High Insomnia (n = 191, 7.3%), Mild Insomnia (n = 574, 21.9%), and High Hypnotics (n = 246, 9.4%). The High Insomnia and Mild Insomnia groups shared similar profiles but different severities in the 7 domains of the Pittsburgh Sleep Quality Index. In contrast, the High Hypnotics group had the lowest Pittsburgh Sleep Quality Index total scores and insomnia severity but had similar mental and physical comorbid patterns as the High Insomnia group. This finding suggests that poor sleep quality in community-dwelling older adults had various feature-based subgroups. It also implicates the development of group-centered interventions.

Associations of OSA and Nocturnal Hypoxemia with Strength and Body Composition in Community Dwelling Middle Aged and Older Men

PURPOSE

Reduced hand grip strength (HGS) is associated with poorer health in chronic conditions, yet there has been little research examining the association with hand grip strength and obstructive sleep apnea (OSA). Further, these studies have not examined, nor adjusted, for muscle mass. The aim of this study was to determine associations between OSA indices, HGS, muscle mass, and fat mass.

PARTICIPANTS AND METHODS

A total of 613 participants (age range 41-88, BMI 28.6 ± 4.3) from the population-based Men Androgen Inflammation Lifestyle Environment and Stress Study underwent in-home overnight polysomnography, assessment of dominant and non-dominant HGS, and dual x-ray absorptiometry to determine whole body muscle mass and fat mass. Linear models determined cross-sectional associations of polysomnographic-derived OSA indices with hand grip strength, muscle mass, and fat mass, whilst adjusting for lifestyle information (income, smoking status, diet, self-reported physical activity), blood sample derived testosterone and systemic inflammation (C-reactive protein), cardiometabolic health (cardiovascular disease, hypertension, type 2 diabetes), and depression.

RESULTS

In adjusted models, reduced dominant HGS was associated with lower oxygen nadir (unstandardised β [B] = 0.19, 95% confidence interval [CI] 0.08 to 0.29), greater time spent below 90% oxygen saturation (B = -0.08, 95% CI -0.14 to -0.02), and increased apnea duration (B = -0.3, 95% CI -0.23 to -0.02). By contrast, there were no associations between HGS and both AHI and REM AHI. Fat mass was consistently associated with worsening OSA indices, whereas muscle mass demonstrated no associations with any OSA index.

CONCLUSION

Our findings suggest impairments in HGS may be related to fat infiltration of muscle, hypoxemia-induced reductions in peripheral neural innervation, or even endothelial dysfunction, which is a common outcome of hypoxemia. Longitudinal data are needed to further examine these hypotheses and establish if reduced grip strength in patients with OSA is associated with long-term adverse health outcomes.

Effect of Sleep Quality on the Prevalence of Sarcopenia in Older Adults: A Systematic Review with Meta-Analysis

Sarcopenia is an age-related condition. However, the prevalence of sarcopenia may increase due to a range of other factors, such as sleep quality/duration. Therefore, the aim of the study is to conduct a systematic review with meta-analysis to determine the prevalence of sarcopenia in older adults based on their self-reported sleep duration. Methods: Three electronic databases were used-PubMed-Medline, Web of Science, and Cochrane Library. We included studies that measured the prevalence of sarcopenia, divided according to sleep quality and excluded studies (a) involving populations with neuromuscular pathologies, (b) not showing prevalence values (cases/control) on sarcopenia, and (c) not including classificatory models to determine sleep quality. Results: high prevalence values in older adults with both long and short sleep duration were shown. However, prevalence values were higher in those with inadequate sleep (<6-8 h or low efficiency) (OR 0.76; 95% CI (0.70-0.83); Q = 1.446; p = 0.695; test for overall effect, Z = 6.01, p < 0.00001). Likewise, higher prevalence levels were shown in men (OR 1.61; 95% CI (0.82-3.16); Q = 11.80; p = 0.0189) compared to women (OR 0.77; 95% CI (0.29-2.03); Q = 21.35; p = 0.0003). Therefore, the prevalence of sarcopenia appears to be associated with sleep quality, with higher prevalence values in older adults who have inadequate sleep.

Grip Strength: An Indispensable Biomarker For Older Adults

Grip strength has been proposed as a biomarker. Supporting this proposition, evidence is provided herein that shows grip strength is largely consistent as an explanator of concurrent overall strength, upper limb function, bone mineral density, fractures, falls, malnutrition, cognitive impairment, depression, sleep problems, diabetes, multimorbidity, and quality of life. Evidence is also provided for a predictive link between grip strength and all-cause and disease-specific mortality, future function, bone mineral density, fractures, cognition and depression, and problems associated with hospitalization. Consequently, the routine use of grip strength can be recommended as a stand-alone measurement or as a component of a small battery of measurements for identifying older adults at risk of poor health status.

The Relationship Between Sleep Duration, Falls, and Muscle Mass: A Cohort Study in an Elderly Chinese Population

Epidemiological studies report that more than half of the people over the age of 65 years suffer from variable sleep problems. In this study, we conducted a cohort study to investigate the relationship between sleep duration, muscle mass, and function within a community-dwelling, elderly Chinese population. Our study population consisted of residents living in the township central hospital of suburban Tianjin, China. We measured muscle strength and walking speed. We divided sleep duration into the following four groups: <7 hours, 7-8 hours, >8-9 hours, and >9 hours. A total of 902 participants completed the 3-year follow-up. We observed a U-shaped relationship between sleep duration and fall risk. Compared with the 7-8-hour group, fall risk within the <7-hour group was 3.67 (2.59, 5.42) times higher and fall risk within the >9-hour group was 2.35 (1.29, 3.52) times higher. After adjustment, muscle mass declined by -6.82% (-11.27%, -3.83%) in the <7-hour group. In summary, we observed a U-shaped relationship between sleep duration and falls. Short sleep duration has a negative relationship with muscle mass decline in a community-dwelling, elderly Chinese population.

Sleep Quality and Attention May Correlate With Hand Grip Strength: FARM Study

OBJECTIVE

To determine the socio-demographic, psychologic, hematologic, or other relevant factors associated with hand grip strength in Korean farmers.

METHODS

A total of 528 healthy Korean farmers were enrolled. Hand grip strength was measured in both hands using a hydraulic dynamometer. Socio-demographic characteristics were assessed and anthropometric measurements were obtained. Psycho-cognitive measurements such as sleep quality (Pittsburgh Sleep Quality Index) and Go/No-Go test response time were conducted. In addition to physical measurements, serologic parameters including insulin-like growth factor 1 were measured. The factors associated with hand grip strength were analyzed using multiple linear regression analysis after adjusting for age, height, and weight.

RESULTS

The mean hand grip strength was associated with the Pittsburgh Sleep Quality Index total score (β=-0.12, p=0.01), the Go/No-Go test response time (β=-0.18, p=0.001), vitamin D (β=0.12, p=0.02), and insulin-like growth factor 1 levels (β=0.1, p=0.045). In female farmers, hand grip strength was only associated with the Pittsburgh Sleep Quality Index total score (β=-0.32, p<0.001).

CONCLUSION

The results of this study demonstrate that hand grip strength was associated with sleep quality and attention in Korean farmers.

Relationship between muscle strength and fall episodes among the elderly: the Yilan study, Taiwan

Background

Fall episodes are not unusual among community residents, especially the elderly, and lower muscle strength is an important issue to address in order to prevent falls.

Methods

A community health survey was conducted in a suburban area of Taiwan, and 1067 older adults were selected for enrollment in the present study. All the enrolled subjects had been visited at their homes; the subjects’ strength of both hands and muscle mass of both legs were measured and well-established questionnaires were finished by certificated paramedic staffs.

Results

The incidence of fall episodes in the previous 1 year in the Yilan elderly population was 15.1%, and the female predominance was significant. A significantly higher prevalence of cataracts was found in group who experienced a fall in the past year (64% vs. 54.9% in the non-fall group). Mild or more severe dementia was much more prevalent in the group who experienced a recent fall (33.8% vs. 25.7% in the non-fall group). The strength of both hands tested as the physical function was 17.6 ± 8.0 kg in the recent fall group, significantly weaker than that in the non-fall group (20.7 ± 8.7 kg). Multivariate regression analysis revealed a greater weekly exercise duration and greater strength of both hands reduced the occurrence of falls among the whole and the female population. The standardized effect sizes of hand grip strength between both groups, not trivial, were 0.29 and 0.37 for the total population and the female subpopulation respectively.

Conclusions

Less weekly exercise duration and weaker muscle strength were f ound to be independent risk factors of fall episode(s) in an elderly Taiwanese population, especially in the female sub-population. Muscle strength, measured by average of both hands grip strength, was the most significantly factor of one-year fall episode(s) accessed retrospectively.

Predictors of Change in Self-Reported Sleep Duration in Community-Dwelling Older Adults: The Shih-Pai Sleep Study, Taiwan

The present study aims to examine and compare the predictors of changes in self-reported sleep duration in older adults. A total of 2,294 participants over the age of 65 in the Shih-Pai Sleep Study were followed-up for an average of 3 years. According to the self-reported sleep duration at baseline and the results of a follow-up survey conducted 3 years later, participants were classified into three categories: mid-range sleepers (6–7 hours), short sleepers (≤5 hours), and long sleepers (≥8 hours). The main outcome variable was the sleep duration at the follow-up survey. A comparison of the results of the baseline and follow-up surveys revealed that only 45.9% of participants remained in the same spectrum of sleep duration in both surveys, with baseline long sleepers having the lowest consistency rate (27.6%). Only incident diseases, with the exception of prevalent diabetes and physical disability, predicted shortening of sleep duration. In contrast, prevalent morbidities or baseline characteristics correlated with the lengthening of sleep duration. The findings suggested that the self-estimated sleep duration fluctuated in a significant proportion of study participants over time. Predictors of lengthening of sleep duration were essentially different from predictors of shortening of sleep duration.