Relative Handgrip Strength Diminishes the Negative Effects of Excess Adiposity on Dependence in Older Adults: A Moderation Analysis

Associations of body mass index, waist circumference and the weight-adjusted waist index with daily living ability impairment in older Chinese people: A cross-sectional study of the Chinese Longitudinal Healthy Longevity Survey

AIM

To investigate the associations of body mass index (BMI), waist circumference (WC) and the weight-adjusted waist index (WWI) with the impairment of activities of daily living (ADL) in older Chinese people.

METHODS

A total of 13 260 participants aged 65 years and older from the 2018 Chinese Longitudinal Healthy Longevity Survey were included in this cross-sectional study. BMI, WC and the WWI were calculated from measurements of height, weight and WC. Binary logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Non-linear correlations were investigated using restricted cubic spline curves.

RESULTS

In multivariate logistic regression fully adjusted for confounding variables, our analyses revealed significant associations between WC and WWI and ADL impairment, with adjusted ORs (95% CI) of 1.01 (1.00, 1.01) and 1.08 (1.03, 1.12), respectively. Meanwhile, participants with a high WWI had a higher risk of ADL impairment compared with those with a low WWI, with an adjusted OR (95% CI) of 1.12 (1.02, 1.23). Subgroup analyses showed that only the association between WWI and ADL impairment did not differ in any of the different populations. In addition, we found that BMI, WC and WWI were non-linearly associated with ADL impairment.

CONCLUSIONS

There are significant associations between WC and WWI and ADL impairment in older Chinese people. The findings show the ability of the WWI to serve as a comprehensive and effective indicator of obesity in older Chinese people and emphasize the importance of assessing WWI in screening and preventing ADL impairment in older people.

[Association of grip strength and knee extensors with nutritional status of community-dwelling older adults]

AIM

To determine the association of hand grip strength and knee extensor strength with the nutritional status of community-dwelling older adults.

MATERIAL AND METHODS

Observational cross-sectional study. Weight and height of 847 older adults were analyzed according to body mass index and classified into four nutritional categories according to the Chilean Ministry of Health. Hand grip and knee extensors strength for both extremities were evaluated. Strength was normalized by body mass. Spearman's correlation between body mass index and muscle strength was used.

RESULTS

The sample was 582 women, 265 men and an average age of 71.72±7.09. The women had a BMI of 30.03±5.48 and the men of 27.64 ± 4.05, the most numerous category was normal weight (n = 288) and the lowest low weight (n = 74). Hand grip strength presented a higher correlation than knee extensors, specifically, right hand grip strength (r: -0.40). The highest correlation and significance were presented by the obese category for all strength measurements, with right hand grip strength being the highest (r: -0.29).

CONCLUSIONS

The increase in the nutritional status of older adults has a negative influence on muscle strength. The best association between body mass index and muscle strength was the right hand grip. The finding of the increase in life expectancy as the nutritional status of the sample decreases stands out. Future studies are needed to generate percentiles and normalized values in the Chilean population.

Association Between Handgrip Strength and Type 2 Diabetes: A Prospective Cohort Study and Systematic Review With Meta-analysis

BACKGROUND

Both absolute (kg) and relative (kg per kg of body weight) handgrip strength (HGS) have been used as indicators of HGS. Multiple studies have explored HGS associations with type 2 diabetes (T2DM); however, prognostic values were inconsistent. We aimed to examine the associations between both absolute and relative HGS and incident T2DM.

METHODS

A total of 12,957 participants aged 40 years and older (mean age 51.0 years, 58.4% men) were followed and enrolled in the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) Cohort Study. Cox proportional hazards regression models were used to examine the association of HGS with incident T2DM. Other prospective studies on HGS and risk of T2DM were identified by searching several electronic databases up to November 31, 2021. Meta-analysis was performed by combining the results from the TCLSIH study and previous prospective cohort studies.

RESULTS

From the TCLSIH Cohort study, after adjustment, relative HGS was inversely associated with T2DM (hazard ratio per 0.1 higher relative HGS 0.667, 95% confidence interval [CI] 0.616, 0.722). However, no significant association between absolute HGS and incident T2DM was found. The meta-analyses showed that per 5 kg higher HGS was associated with a 5% (95% CI 2%, 8%) lower risk of T2DM and each 0.1 higher relative HGS was associated with a 22% (95% CI 14%, 29%) lower risk of T2DM.

CONCLUSION

The results from our cohort study and meta-analysis suggest that relative HGS was better than absolute HGS in predicting incident T2DM. Adiposity was an important factor that mediates the association between HGS and T2DM.

Relative Sit-to-Stand Muscle Power Predicts an Older Adult's Physical Independence at Age of 90 Yrs Beyond That of Relative Handgrip Strength, Physical Activity, and Sedentary Time: A Cross-sectional Analysis

OBJECTIVES

Muscle power is important for an older adult's physical independence and can be easily estimated using the sit-to-stand test. This investigation aimed to assess whether muscle power estimated using the sit-to-stand test could identify older adults at risk of losing physical independence beyond handgrip strength, physical activity, and sedentary time and to develop minimal sit-to-stand power thresholds.

DESIGN

Physical independence was assessed cross-sectionally in older adults using a composite physical function questionnaire. Muscle power was calculated using the 30-sec sit-to-stand test. Muscle strength was determined using a handgrip dynamometer. Physical activity and sedentary time were assessed by accelerometry. Multiple logistic regression was used to assess the independent association between sit-to-stand power and projected physical independence ( n = 737). Receiver operator characteristic curves were used to develop sit-to-stand power cut points ( N = 1748).

RESULTS

Sit-to-stand power proved to be the best predictor of physical independence in later life regardless of handgrip strength, physical activity, and sedentary time (standardized B = 0.45, -0.02, 0.12, -0.28, respectively). Sex- and age-specific cutoffs for sit-to-stand power had good discriminatory ability (area under the curve = 0.75-0.78 [women], 0.76-0.82 [men]).

CONCLUSIONS

Sit-to-stand power can be used as a simple and practical screening tool to assess an older adult's future physical independence.

Can Muscle Mass Be Maintained with A Simple Resistance Intervention in the Older People? A Cluster Randomized Controlled Trial in Thailand

The aging population is rapidly increasing worldwide. Sarcopenia is a common and important health problem among older people. The prevalence of sarcopenia among older Thai adults is increasing. Exercise intervention for sarcopenia prevention may significantly improve muscle strength, body balance, and muscle mass. Therefore, this study aimed to investigate the effects of a simple resistance intervention (SRI) program in preventing sarcopenia on physiological outcomes among community-dwelling older Thai adults. This study was a 12-week randomized controlled trial, which included 80 community-dwelling older adults in Chiang Mai, Thailand, who were randomly assigned into control (40 participants who performed usual exercise) and intervention (40 participants who performed the SRI program) groups. The SRI program was a home-based program consisting of 30 min of resistance exercise three times/week for 12 weeks, health education on sarcopenia. After 12 weeks, all physiological outcomes were measured and were significantly improved in the intervention group compared with baseline; hand grip, skeletal muscle mass index, and walking speed were significantly improved in the intervention group compared with the control group. Based on our results, the SRI program may prevent muscle weakness in community-dwelling older people in Thailand.

Comparison of methods to identify individuals with obesity at increased risk of functional impairment among a population of home-dwelling older adults

Obesity is associated with increased muscle mass and muscle strength. Methods taking into account the total body mass to reveal obese older individuals at increased risk of functional impairment are needed. Therefore, we aimed to detect methods to identify obese older adults at increased risk of functional impairment. Home-dwelling older adults (n 417, ≥ 70 years of age) were included in this cross-sectional study. Sex-specific cut-off points for two obesity phenotypes (waist circumference (WC) and body fat mass (FM %)) were used to divide women and men into obese and non-obese groups, and within-sex comparisons were performed. Obese women and men, classified by both phenotypes, had similar absolute handgrip strength (HGS) but lower relative HGS (HGS/total body mass) (P < 0·001) than non-obese women and men, respectively. Women with increased WC and FM %, and men with increased WC had higher appendicular skeletal muscle mass (P < 0·001), lower muscle quality (HGS/upper appendicular muscle mass) (P < 0·001), and spent longer time on the stair climb test and the repeated sit-to-stand test (P < 0·05) than non-obese women and men, respectively. Absolute muscle strength was not able to discriminate between obese and non-obese older adults. However, relative muscle strength in particular, but also muscle quality and physical performance tests, where the total body mass was taken into account or served as an extra load, identified obese older adults at increased risk of functional impairment. Prospective studies are needed to determine clinically relevant cut-off points for relative HGS in particular.

Association between handgrip strength and the risk of new-onset metabolic syndrome: a population-based cohort study

OBJECTIVES

A lower relative handgrip strength (HGS) may disrupt metabolic homeostasis and then lead to metabolic syndrome (MetS). There is a paucity of longitudinal studies to examine whether relative HGS at baseline is linked to incident MetS. Thus, the purpose of the present study was to explore the association between relative HGS and new-onset MetS.

DESIGN

This is an observational and longitudinal research.A nationally representative sample of population in China.

PARTICIPANTS

A total of 3350 subjects without MetS were selected for analysis in the present study. Data are from the China Health and Retirement Longitudinal Study (2011-2015).

OUTCOME MEASURES

We calculated the relative HGS by dividing the HGS by body weight. Participants were divided into gender-specific quartiles. We estimated HRs for MetS and its components using Cox proportional hazard models according to the relative HGS categories.

RESULTS

After multiple adjustment, the risk of MetS increased with the lower quartile of relative HGS in both sexes. Using the highest quartile (Q4) as a reference, the HR for quartile Q3-1 was 1.49 (0.95, 2.34), 1.67 (1.08, 2.59) and 1.76 (1.12, 2.78), respectively, in men, and 1.14 (0.82, 1.58), 1.30 (1.02, 1.57) and 1.28 (1.03, 1.55), respectively, in women. Additionally, we observed that relative HGS was negatively or inversely associated with the risk of abdominal obesity in both sexes.

CONCLUSIONS

The current study demonstrated that relative HGS was inversely and independently associated with an increased risk of MetS and abdominal obesity, suggesting a possible role of relative HGS as a useful and simple index for muscle strength in the prediction of occurrence of MetS.

Circulating Cytokines and Lower Body Muscle Performance in Older Adults at Hospital Admission

BACKGROUND

Aging-related traits, including gradual loss of skeletal muscle mass and chronic inflammation, are linked to altered body composition and impaired physical functionality, which are important contributing factors to the disabling process. We sought to explore the potential relationship between lower-body muscle strength decline and inflammatory mediators in older adults.

METHODS

We performed a cross-sectional analysis in 38 older adults admitted to an acute care of the elderly unit (57.9% women, mean age=87.9±4.9 years; mean body mass index [BMI]=26.5±4.7 kg/m2). Clinical and functional outcomes including weight, height, BMI, dependence, physical and cognitive performance, and muscle strength measured by one-repetition maximum (1RM) for leg-extension, leg-press, chest-press and handgrip strength, were assessed. Blood serum content of 59 cytokines, chemokines and growth factors was assessed by protein arrays. Multivariate linear regression analyses were used to examine the relationship between cytokine concentrations and muscle strength parameters.

RESULTS

After controlling for confounding factors (age, sex, BMI, cumulative illness rating score and physical performance score), 1RM leg-press had a significant negative relationship with GRO (CXCL2) (β= -18.13, p=0.049), MIG (CXCL9) (β= -13.94, p=0.004), IGF-1 (β= -19.63, p=0.003), CK-BETA 8 (CCL23) (β= -28.31, p=0.018) and GCP-2 (CXCL6) (β= -25.78, p=0.004). Likewise, 1RM leg-extension had a significant negative relationship with IGFBP-1 (β= -11.49, p=0.023).

CONCLUSIONS

Thus, several serum cytokines/chemokines and growth factors are negatively associated with lower muscle strength in older patients. Further investigation is required to elucidate the mechanism of elevated inflammatory mediators leading to lower muscle strength.