OBJECTIVE: To investigate the available evidence on the components of sarcopenia in geriatric rehabilitation, and to examine whether changes in different settings are associated with sarcopenia. DATA SOURCES: PubMed, the Cochrane Central Register of Controlled Trials in the Cochrane Library, and EMBASE were searched from initiation to August 30th, 2021. STUDY SELECTION: We included randomized controlled trials (RCTs) of older adults receiving geriatric rehabilitation that included strength exercise training. DATA EXTRACTION: The following study contents were extracted: study design, patient characteristics, sample size, description of the rehabilitation setting, follow-up timepoint and outcomes. The main outcomes were muscle mass, muscle strength and physical performance. DATA SYNTHESIS: Weighted mean difference for 'Timed up-and-go' score and standardized mean difference for other parameters were calculated. CONCLUSIONS: Center-based geriatric rehabilitation improved lower limb strength and Timed up-and-go test score to a greater extent than home-based geriatric rehabilitation in elderly people. Center-based training seems to show a minor superior effect on gait speed in prolonged follow-up rather than at the endpoint of intervention. To draw a stronger conclusion, further high-quality trials with standard protocols and longer follow-up are needed.

(1) Background: To review the associated factors of sarcopenia in community-dwelling older adults. (2) Methods: PubMed, Embase, Web of Science, and four Chinese electronic databases were searched for observational studies that reported the associated factors of sarcopenia from inception to August 2021. Two researchers independently selected the literature, evaluated their quality, and extracted relevant data. The pooled odds ratio (OR) and its 95% confidence interval (CI) were calculated for each associated factors of sarcopenia using random-effects/fixed-effects models. Publication bias was assessed using funnel plot and the Eggers test. We performed statistical analysis using Stata 15.0 software. (3) Results: A total of 68 studies comprising 98,502 cases were included. Sociodemographic associated factors of sarcopenia among community-dwelling older adults included age (OR = 1.12, 95% CI: 1.10-1.13), marital status (singled, divorced, or widowed) (OR = 1.57, 95% CI: 1.08-2.28), disability for activities of daily living (ADL) (OR = 1.49, 95% CI: 1.15-1.92), and underweight (OR = 3.78, 95% CI: 2.55-5.60). Behavioral associated factors included smoking (OR = 1.20, 95% CI: 1.10-1.21), physical inactivity (OR = 1.73, 95% CI: 1.48-2.01), malnutrition/malnutrition risk (OR = 2.99, 95% CI: 2.40-3.72), long (OR = 2.30, 95% CI: 1.37-3.86) and short (OR = 3.32, 95% CI: 1.86-5.93) sleeping time, and living alone (OR = 1.55, 95% CI: 1.00-2.40). Disease-related associated factors included diabetes (OR = 1.40, 95% CI: 1.18-1.66), cognitive impairment (OR = 1.62, 95% CI: 1.05-2.51), heart diseases (OR = 1.14, 95% CI: 1.00-1.30), respiratory diseases (OR = 1.22, 95% CI: 1.09-1.36), osteopenia/osteoporosis (OR = 2.73, 95% CI: 1.63-4.57), osteoarthritis (OR = 1.33, 95% CI: 1.23-1.44), depression (OR = 1.46, 95% CI: 1.17-1.83), falls (OR = 1.28, 95% CI: 1.14-1.44), anorexia (OR = 1.50, 95% CI: 1.14-1.96), and anemia (OR = 1.39, 95% CI: 1.06-1.82). However, it remained unknown whether gender (female: OR = 1.10, 95% CI: 0.80-1.51; male: OR = 1.50, 95% CI: 0.96-2.34), overweight/obesity (OR = 0.27, 95% CI: 0.17-0.44), drinking (OR = 0.92, 95% CI: 0.84-1.01), hypertension (OR = 0.98, 95% CI: 0.84-1.14), hyperlipidemia (OR = 1.14, 95% CI: 0.89-1.47), stroke (OR = 1.70, 95% CI: 0.69-4.17), cancer (OR = 0.88, 95% CI: 0.85-0.92), pain (OR = 1.08, 95% CI: 0.98-1.20), liver disease (OR = 0.88, 95% CI: 0.85-0.91), and kidney disease (OR = 2.52, 95% CI: 0.19-33.30) were associated with sarcopenia. (4) Conclusions: There are many sociodemographic, behavioral, and disease-related associated factors of sarcopenia in community-dwelling older adults. Our view provides evidence for the early identification of high-risk individuals and the development of relevant interventions to prevent sarcopenia in community-dwelling older adults.

BACKGROUND: Beta-hydroxy-beta-methylbutyrate (HMB), a metabolite of the branched-chain amino acid leucine, has been investigated as a potential supplement to improve muscle quality; however, whether HMB supplementation has beneficial effects on muscle loss in older adults remains unclear. DESIGN: Systematic review with meta-analysis. SETTING: PubMed, Medline and EMBASE databases were searched from the earliest possible year to September 2014. PARTICIPANTS: Individuals aged 65 years and older that reported absolute changes in body composition with use of HMB. MEASUREMENTS: Two review authors working independently reviewed the trials, and standard mean difference was calculated using a fixed effects model. RESULTS: A total of seven randomized controlled trials were included, in which 147 older adults received HMB intervention and 140 were assigned to control groups. The meta-analysis showed greater muscle mass gain in the intervention groups compared with the control groups (standard mean difference=0.352kg; 95% confidence interval: 0.11, 0.594; Z value=2.85; P=0.004). There were no significant fat mass changes between intervention and control groups (standard mean difference=-0.08kg; 95% confidence interval: -0.32, 0.159; Z value=0.66; P=0.511). CONCLUSION: Beta-hydroxy-beta-methylbutyrate supplementation contributed to preservation of muscle mass in older adults. HMB supplementation may be useful in the prevention of muscle atrophy induced by bed rest or other factors. Further studies are needed to determine the precise effects of HMB on muscle strength and physical function in older adults