Exploring the Role of Muscle Mass,Obesity, and Age in the Relationship Between Muscle Quality and Physical Function

BackgroundDivergent conclusions emerge from the literature regarding the relationship between muscle quality (defined as muscle strength per unit of muscle mass) and physical function. These contrasted results may be due to the influence of factors such as age, obesity, and muscle mass itself. Consequently, the aim of the present study was to explore the role of these factors in the relationship between muscle quality (MQ) and physical function.MethodsData are from 312 individuals (97 men and 215 women) aged 50 years and older. Body composition (dual energy X-ray absorptiometry) and knee extension strength of the right leg (1 repetition maximum) were assessed. Appendicular lean body mass index (AppLBMI) and MQ (knee extension strength /right leg lean mass) were calculated. A composite score of physical function was created based on the timed up-and-go, alternate step, sit-to-stand, and balance tests.ResultsMQ was significantly associated with physical function when AppLBMI (β = 0.179; P = .004) and body mass index (BMI) (β = 0.178; P = .003), but not age (β = 0.065; P = .26), were included in regression analysis. AppLBMI (β = 0.221; P < .001), BMI (β = 0.234; P < .001), and age (β = 0.134; P = .018) significantly interacted with MQ to determine physical function.ConclusionsOur results show that muscle mass, obesity, and age influence the relationship between MQ and physical function, suggesting that these factors should be taken into account when interpreting MQ. Even so, higher levels of MQ were associated with higher physical function scores. Nutritional and physical activity interventions may be designed in this regard.     

Acute Muscle Mass Loss Predicts Long-Term Fatigue,Myalgia, and Health Care Costs in COVID-19 Survivors

ObjectiveWe examined the impact of loss of skeletal muscle mass in post-acute sequelae of SARS-CoV-2 infection, hospital readmission rate, self-perception of health, and health care costs in a cohort of COVID-19 survivors.DesignProspective observational study.Setting and ParticipantsTertiary Clinical Hospital. Eighty COVID-19 survivors age 59 ± 14 years were prospectively assessed.MethodsHandgrip strength and vastus lateralis muscle cross-sectional area were evaluated at hospital admission, discharge, and 6 months after discharge. Post-acute sequelae of SARS-CoV-2 were evaluated 6 months after discharge (main outcome). Also, health care costs, hospital readmission rate, and self-perception of health were evaluated 2 and 6 months after hospital discharge. To examine whether the magnitude of muscle mass loss impacts the outcomes, we ranked patients according to relative vastus lateralis muscle cross-sectional area reduction during hospital stay into either “high muscle loss” (?18 ± 11%) or “low muscle loss” (?4 ± 2%) group, based on median values.ResultsHigh muscle loss group showed greater prevalence of fatigue (76% vs 46%, P = .0337) and myalgia (66% vs 36%, P = .0388), and lower muscle mass (?8% vs 3%, P < .0001) than low muscle loss group 6 months after discharge. No between-group difference was observed for hospital readmission and self-perceived health (P > .05). High muscle loss group demonstrated greater total COVID-19-related health care costs 2 ($77,283.87 vs. $3057.14, P = .0223, respectively) and 6 months ($90,001.35 vs $12, 913.27, P = .0210, respectively) after discharge vs low muscle loss group. Muscle mass loss was shown to be a predictor of total COVID-19-related health care costs at 2 (adjusted β = $10, 070.81, P < .0001) and 6 months after discharge (adjusted β = $9885.63, P < .0001).Conclusions and ImplicationsCOVID-19 survivors experiencing high muscle mass loss during hospital stay fail to fully recover muscle health. In addition, greater muscle loss was associated with a higher frequency of post-acute sequelae of SARS-CoV-2 and greater total COVID-19-related health care costs 2 and 6 months after discharge. Altogether, these data suggest that the loss of muscle mass resulting from COVID-19 hospitalization may incur in an economical burden to health care systems.     

Daily Supplementation With Whey,Soy, or Whey-Soy Blended Protein for 6 Months Maintained Lean Muscle Mass and Physical Performance in Older Adults With Low Lean Mass

BackgroundFew studies have investigated the effect of long-term protein supplementation alone on muscle health in older adults with low lean mass.ObjectiveTo determine the effect of whey, soy or whey-soy blended protein supplementation on lean muscle mass and physical performance in older adults with low lean mass.DesignA 4-arm randomized controlled trial.Participants/settingChinese older adults (n = 123, 65-79 years) with low lean mass (appendicular skeletal muscle index < 7.0 kg/m² in men and < 5.4 kg/m² in women) living in the urban area of Guangzhou participated between October 2015 and June 2016.InterventionParticipants were randomly assigned to receive approximately 16 g/d of whey, soy, or whey-soy blend protein or maintained habitual diets in control group for 6 months.Main outcome measuresLean mass, handgrip strength, and physical performance (gait speed, chair stand test, and Short Physical Performance Battery) were assessed at baseline and 6 months.Statistical analysesTwo-way analysis of variance with the main effects of treatment and time and treatment × time interaction and analysis of covariance was used to determine differences in outcomes.ResultsAppendicular skeletal muscle index, lean mass, percent lean mass in legs and appendicular areas, gait speed, and Short Physical Performance Battery score were maintained in the treatment groups and decreased in the control group, resulting in significant reduction in these variables from baseline in the control compared with treatment groups (all P < .01; percent differences between treatment and control groups ranged from 80% to 156%). The chair stand test time at month 6 decreased from baseline in the treatment groups and increased in the control group, resulting in a significant increase in the control compared with treatment groups (all P < .01; percent differences between treatment and control groups ranged from 132% to 155%). Handgrip strength remained unchanged. There were no significant differences in outcomes among treatment groups.ConclusionsSupplementation with whey, soy, or whey-soy blended protein for 6 months equally maintained lean muscle mass and physical performance in older adults with low lean mass.     

Four-Month Course of Soluble Milk Proteins Interacts With Exercise to Improve Muscle Strength and Delay Fatigue in Elderly Participants

BackgroundThe benefit of protein supplementation on the adaptive response of muscle to exercise training in older people is controversial.ObjectiveTo investigate the independent and combined effects of a multicomponent exercise program with and without a milk-based nutritional supplement on muscle strength and mass, lower-extremity fatigue, and metabolic markers.DesignA sample of 48 healthy sedentary men aged 60.8 ± 0.4 years were randomly assigned to a 16-week multicomponent exercise training program with a milk-based supplement containing, besides proteins [total milk proteins 4 or 10 g/day or soluble milk proteins rich in leucine (PRO) 10 g/day], carbohydrates and fat. Body composition, muscle mass and strength, and time to task failure, an index of muscle fatigue, were measured. Blood lipid, fibrinogen, creatine phosphokinase, glucose, insulin, C-reactive protein, interleukin-6, tumor necrosis factor-α soluble receptors, and endothelial markers were assessed.ResultsBody fat mass was reduced after the 4-month training program in groups receiving 10 g/day of protein supplementation (P < .01). The training program sustained with the daily 10 g/day PRO was associated with a significant increase in dominant fat free mass (+5.4%, P < .01) and in appendicular muscle mass (+4.5%, P < .01). Blood cholesterol was decreased in the trained group receiving 10 g/day PRO. The index of insulin resistance (homeostasis model assessment–insulin resistance) and blood creatine phosphokinase were reduced in the groups receiving 10 g/day PRO, irrespective of exercise. The inflammatory and endothelial markers were not different between the groups. Training caused a significant improvement (+10.6% to 19.4%, P < .01) in the maximal oxygen uptake. Increased maximum voluntary contraction force was seen in the trained groups receiving 10 g/day of proteins (about 3%, P < .05). Time to task failure was improved in the trained participants receiving a 10 g/day supplementation with PRO (P < .01).ConclusionsSoluble milk proteins rich in leucine improved time to muscle failure and increase in skeletal muscle mass and strength after prolonged multicomponent exercise training in healthy older men.     

Sarcopenia,Low Handgrip Strength,and Low Absolute Muscle Mass Predict Long-Term Mortality in Older Hospitalized Patients: An Observational Inception Cohort Study

ObjectiveSarcopenia is highly prevalent in hospitalized older patients and associated with short-term mortality. This study aimed to investigate whether sarcopenia and its measures handgrip strength (HGS) and muscle mass at hospital admission were associated with long-term mortality in a cohort of hospitalized older patients.DesignObservational, prospective, longitudinal inception cohort study.Setting and ParticipantsAcademic teaching hospital; patients age ≥70 years admitted to the internal medicine, acute admission, trauma, or orthopedic wards.MethodsHGS and muscle mass were measured at admission using a hand dynamometer and bioelectrical impedance analysis. Sarcopenia was determined based on the European Working Group on Sarcopenia in Older People definition. HGS and muscle mass (skeletal muscle mass index, appendicular lean mass, relative skeletal muscle mass) were expressed as sex-specific tertiles. The associations of sarcopenia, HGS, and muscle mass with mortality (during a follow-up of 3.4-4.1 years) were analyzed using Cox regression, adjusted for age, sex, comorbidity, and weight or height. Associations of HGS and muscle mass were stratified by sex.ResultsOut of 363 patients [mean age: 79.6 years (standard deviation: 6.4), 49.9% female] 49% died. Probable sarcopenia (prevalence of 53.7%) and sarcopenia (prevalence of 20.8%) were significantly associated with long-term mortality [hazard ratio (HR) 1.53, 95% confidence interval (CI) 1.08?2.17 and 1.71 95% CI 1.12?2.61, respectively]. Low HGS, skeletal muscle mass index, and appendicular lean mass were associated with a higher mortality risk (lowest tertile vs highest tertile: HR 2.660, 95% CI 1.40?5.05; HR 1.95, 95% CI 1.06?3.58 and HR 1.99 (95% CI 1.12?3.53) in male patients. No statistically significant associations of relative muscle mass with mortality were found.Conclusions and ImplicationsSarcopenia and its measures (low HGS and low absolute muscle mass at admission) predict long-term mortality in older hospitalized patients.     

Muscle Density,but Not Size,Correlates Well With Muscle Strength and Physical Performance

ObjectivesThere is increasing evidence that muscle volume and mass are poor predictors of muscle strength and physical performance. Other assessments of muscle quality such as skeletal muscle density measured by computed tomography (CT) may be more important. The aim of this study was to explore associations of muscle size and density with handgrip strength (HGS) and the Timed Up and Go test (TUG). We also hypothesized that the strength of these associations would depend on the specific muscle of muscle group, namely trunk, hip, and mid-thigh muscles.DesignCross-sectional study.Setting and ParticipantsUniversity hospital; 316 volunteers aged 59 to 85 years.MethodsHGS, TUG, and quantitative CT imaging of the lumber, hip, and mid-thigh were performed in volunteers. From the CT images, cross-sectional area and attenuation were determined for the gluteus muscle, trunk muscle at vertebrae L2 level, and mid-thigh muscle.ResultsIn men and women, associations of muscle area with TUG were insignificant after adjustment for age, height, and weight. Associations with HGS were only significant in men for the gluteus maximus and the mid-thigh but slopes were rather low (β < 0.20). Associations between muscle density and TUG/HGS were more pronounced, in particular for HGS. After adjustment, associations with TUG were significant in women for the gluteus maximus and trunk muscle even (β ?0.06, P .001 and β ?0.07, P .031, respectively).Conclusions and ImplicationsMuscle density is more strongly associated with muscle strength than muscle size andin women muscle density was also more strongly associated than muscle size with physical performance. Therefore, muscle density may represent a more clinically meaningful surrogate of muscle performance than muscle size. Muscle density measurements of trunk and gluteus muscles can be easily obtained from routine CT scan and, therefore, may become an important measurement to diagnose and screen for sarcopenia.     

Depression is Associated With Sarcopenia Due to Low Muscle Strength: Results From the ELSA-Brasil Study

ObjectivesTo investigate the association of sarcopenia and its defining components with depression in Brazilian middle-aged and older adults.DesignCross-sectional study.Setting and ParticipantsThis analysis included 5927 participants from the ELSA-Brasil Study second data collection, aged 55 years and older, with complete data for exposure, outcome, and covariates.MeasuresMuscle mass was evaluated by bioelectrical impedance analysis and muscle strength by hand-grip strength. Sarcopenia was defined according to the Foundation for the National Institutes of Health (FNIH) criteria. Depression was assessed using the Clinical Interview Scheduled Revised (CIS-R). Information on sociodemographic characteristics, lifestyle, and clinical comorbidities were also obtained.ResultsThe frequencies of sarcopenia, presarcopenia, low muscle mass, low muscle strength, and low muscle strength without loss of muscle mass was 1.9%, 18.8%, 20.7%, 4.8%, and 2.9%, respectively. After adjustment for sociodemographic characteristics, clinical conditions, and lifestyle factors, depression was associated with sarcopenia (odds ratio [OR] = 2.23, 95% confidence interval [CI] = 1.11-4.48, P = .024) and low muscle strength (OR = 1.94, 95% CI = 1.20-3.15, P = .007), but it was not associated with presarcopenia, low muscle mass, and low muscle strength without loss of muscle mass.ConclusionsDepression is associated with sarcopenia defined by the FNIH criteria mainly because of its association with weakness. Future studies are needed to clarify the temporal relationship between both conditions.     

Effectiveness of a Diet and Resistance Exercise Intervention on Muscle Health in Older Adults: ProMuscle in Practice

ObjectivesClinical studies show that resistance exercise and a protein-rich diet can counteract the age-related decline of muscle mass, strength, and physical performance. The aim of the ProMuscle in Practice study was to test effectiveness of a resistance exercise and dietary protein intervention for older adults implemented in a real-life setting.DesignA randomized controlled multicenter intervention study.Setting and ParticipantsOne hundred sixty-eight community-dwelling older adults were included (age 75 ± 6 years). A 12-week intensive support intervention including progressive resistance exercise supervised by a physiotherapist and dietitian guidance on increasing protein intake was followed by a voluntary 12-week moderate support intervention to continue the adapted lifestyle pattern. The control group received no intervention.MethodsCompliance was measured through attendance lists and 3-day food records. Physical functioning, leg strength (3-repetition maximum, knee extension strength), lean body mass [(LBM) dual-energy X-ray absorptiometry], and quality of life (5-level EQ-5D) were measured at baseline, and after 12 and 24 weeks. Differences in change between groups were assessed with linear mixed model analysis.ResultsThe intervention group increased protein intake and attended 83.6% of the training sessions. Short Physical Performance Battery score slightly increased in intervention participants [from 10.1 (95% confidence interval 9.7–10.5) to 10.4 (10.0–10.8) at week 12 and 10.6 (10.2–10.9) at week 24], where control participants decreased (time × treatment interactions, P < .05). Improvements in intervention group compared with controls were also observed for Timed Up-and-Go, strength and LBM at both time points (time × treatment interactions, P < .05). No difference between groups was found for the 6-Minute Walking Test, activities of daily living, and quality of life.Conclusions and ImplicationsProMuscle in Practice was effective on improving muscle strength and LBM, with small changes in the composite function score in community-dwelling older adults in a real-life setting. Further research should explore feasibility of real-life implementation, as well as improving long-term compliance.     

Effect of a Simple Exercise Program on Hospitalization-Associated Disability in Older Patients: A Randomized Controlled Trial

ObjectiveHospitalization-associated disability [HAD, ie, the loss of ability to perform ≥1 basic activities of daily living (ADLs) independently at discharge] is a frequent condition among older patients. The present study assessed whether a simple inpatient exercise program decreases HAD incidence in acutely hospitalized very old patients.DesignIn this randomized controlled trial (Activity in Geriatric Acute Care) participants were assigned to a control or intervention group and were assessed at baseline, admission, discharge, and 3 months thereafter.Setting and ParticipantsIn total, 268 patients (mean age 88 years, range 75–102) admitted to an acute care for older patients unit of a public hospital were randomized to a control (n = 125) or intervention (exercise) group (n = 143).MethodsBoth groups received usual care, and patients in the intervention group also performed simple supervised exercises (walking and rising from a chair, for a total duration of ∼20 minutes/day). We measured ADL function (Katz index) and incident HAD at discharge and after 3 months (primary outcome) and Short Physical Performance Battery, ambulatory capacity, number of falls, rehospitalization, and death during a 3-month follow-up (secondary outcomes).ResultsMedian duration of hospitalization was 7 days (interquartile range 4 days). The intervention group had a lower risk of HAD with reference to both baseline [odds ratio (OR) 0.36; 95% confidence interval (CI) 0.17–0.76, P = .007] and admission (OR 0.29; 95% CI 0.10–0.89, P = .030). A trend toward an improved ADL function at discharge vs admission was found in the intervention group compared with controls (OR 0.32; 95% CI ‒0.04 to 0.68; P = .083). No between-group differences were noted for the other endpoints (all P > .05).Conclusion and ImplicationsA simple inpatient exercise program decreases risk of HAD in acutely hospitalized, very old patients.     

Protein Supplementation Improves Physical Performance in Frail Elderly People: A Randomized,Double-Blind,Placebo-Controlled Trial

ObjectivesProtein supplementation has been proposed as an effective dietary strategy to increase skeletal muscle mass and improve physical performance in frail elderly people. Our objective was to assess the impact of 24 weeks of dietary protein supplementation on muscle mass, strength, and physical performance in frail elderly people.Design/setting/participantsA total of 65 frail elderly subjects were included and randomly allocated to either daily protein or placebo supplementation (15 g protein at breakfast and lunch).MeasurementsSkeletal muscle mass (DXA), muscle fiber size (muscle biopsy), strength (1-RM), and physical performance (SPPB) were assessed at baseline, and after 12 and 24 weeks of dietary intervention.ResultsSkeletal muscle mass did not change in the protein- (from 45.8 ± 1.7 to 45.8 ± 1.7 kg) or placebo-supplemented group (from 46.7 ± 1.7 to 46.6 ± 1.7 kg) following 24 weeks of intervention (P > .05). In accordance, type I and II muscle fiber size did not change over time (P > .05). Muscle strength increased significantly in both groups (P < .01), with leg extension strength tending to increase to a greater extent in the protein (57 ± 5 to 68 ± 5 kg) compared with the placebo group (57 ± 5 to 63 ± 5 kg) (treatment × time interaction effect: P = .059). Physical performance improved significantly from 8.9 ± 0.6 to 10.0 ± 0.6 points in the protein group and did not change in the placebo group (from 7.8 ± 0.6 to 7.9 ± 0.6 points) (treatment × time interaction effect: P = .02).ConclusionDietary protein supplementation improves physical performance, but does not increase skeletal muscle mass in frail elderly people.     

One Week of Hospitalization Following Elective Hip Surgery Induces Substantial Muscle Atrophy in Older Patients

Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Effect of Angiotensin System Inhibitors on Physical Performance in Older People – A Systematic Review and Meta-Analysis

ObjectivePreclinical and observational data suggest that angiotensin converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs) may be able to improve physical performance in older people via direct and indirect effects on skeletal muscle. We aimed to summarize current evidence from randomised controlled trials in this area.DesignSystematic review and meta-analysis.Setting and ParticipantsRandomized controlled trials enrolling older people, comparing ACEi or ARB to placebo, usual care or another antihypertensive agent, with outcome data on measures of physical performance.MethodsWe searched multiple electronic databases without language restriction between inception and the end of February 2020. Trials were excluded if the mean age of participants was <65 years or treatment was targeting specific diseases known to affect muscle function (for example heart failure). Data were sought on measures of endurance and strength. Standardized mean difference (SMD) treatment effects were calculated using random-effects models with RevMan software.ResultsEight trials (952 participants) were included. Six trials tested ACEi, 2 trials tested ARBs. The mean age of participants ranged from 66 to 79 years, and the duration of treatment ranged from 2 months to 1 year. Trials recruited healthy older people and people with functional impairment; no trials specifically targeted older people with sarcopenia. Risk of bias for all trials was low to moderate. No significant effect was seen on endurance outcomes [6 trials, SMD 0.04 (95% CI –0.22 to 0.29); P = .77; I² = 53%], strength outcomes [6 trials, SMD –0.02 (95% CI –0.18 to 0.14), P = .83, I² = 21%] or the short physical performance battery [3 trials, SMD –0.04 (95% CI –0.19 to 0.11), P = .60, I² = 0%]. No evidence of publication bias was evident on inspection of funnel plots.Conclusions and ImplicationsExisting evidence does not support the use of ACE inhibitors or angiotensin receptor blockers as a single intervention to improve physical performance in older people.     

Effect of Protein Supplementation on Physical Performance in Older People With Sarcopenia–A Randomized Controlled Trial

ObjectivesTo test the long-term effects of whey-enriched protein supplementation on muscle and physical performance.DesignA 12-month randomized controlled double blind trial with a 43-month of post-trial follow-up.SettingPorvoo, Finland.ParticipantsA total of 218 older (>74 years of age) community-dwelling people with sarcopenia.Intervention(1) Control with no supplementation; (2) isocaloric placebo; and (3) 20 g × 2 whey-enriched protein supplementation. All participants were given instructions on home-based exercise, dietary protein, and vitamin D supplementation of 20 μg/d.MeasurementsPhysical performance was assessed by short physical performance battery and continuous summary physical performance scores. Hand grip strength and calf intracellular resistance based skeletal muscle index were measured by bioimpedance spectroscopy. The measurements were performed at 0, 6, and 12 months. The post-trial follow-up was performed by a postal questionnaire and national census record data.ResultsThe participants were older (75-96 years of age) and mostly women (68%). The test supplements had no significant effects on physical performance; the 12-month changes for short physical performance battery were −0.55, −.05, and 0.03 points in control, isocaloric, and protein groups (P = .17), respectively. The changes in continuous summary physical performance scores were similar between the intervention groups (P = .76). The hand grip strength decreased significantly in all intervention groups, and the 12-month changes in calf intracellular resistance-based skeletal muscle index were minor and there were no differences between the intervention groups. One-half of the patients (56%) in both supplement groups reported mild gastrointestinal adverse effects. Differences were found neither in the all-cause mortality nor physical functioning in the post-trial follow-up.ConclusionsThe whey-enriched protein supplementation in combination with low intensity home-based physical exercise did not attenuate the deterioration of muscle and physical performance in community-dwelling older people with sarcopenia.     

Protein Supplementation Increases Muscle Mass Gain During Prolonged Resistance-Type Exercise Training in Frail Elderly People: A Randomized,Double-Blind,Placebo-Controlled Trial

ObjectivesProtein supplementation has been proposed as an effective dietary strategy to augment the skeletal muscle adaptive response to prolonged resistance-type exercise training in elderly people. Our objective was to assess the impact of protein supplementation on muscle mass, strength, and physical performance during prolonged resistance-type exercise training in frail elderly men and women.Design/setting/participantsA randomized, double-blind, placebo-controlled trial with 2 arms in parallel among 62 frail elderly subjects (78 ± 1 year). These elderly subjects participated in a progressive resistance-type exercise training program (2 sessions per week for 24 weeks) during which they were supplemented twice daily with either protein (2 1 15 g) or a placebo.MeasurementsLean body mass (DXA), strength (1-RM), and physical performance (SPPB) were assessed at baseline, and after 12 and 24 weeks of intervention.ResultsLean body mass increased from 47.2 kg (95% CI, 43.5–50.9) to 48.5 kg (95% CI, 44.8–52.1) in the protein group and did not change in the placebo group (from 45.7 kg, 95% CI, 42.1–49.2 to 45.4 kg, 95% CI, 41.8–48.9) following the intervention (P value for treatment × time interaction = .006). Strength and physical performance improved significantly in both groups (P = .000) with no interaction effect of dietary protein supplementation.ConclusionsProlonged resistance-type exercise training represents an effective strategy to improve strength and physical performance in frail elderly people. Dietary protein supplementation is required to allow muscle mass gain during exercise training in frail elderly people. Trial Registration: clinicaltrials.gov identifier: NCT01110369.     

Association of Creatinine-to-Cystatin C Ratio with Myosteatosis and Physical Performance in Older Adults: The Japan Shimanami Health Promoting Program

ObjectiveSarcopenia is a risk factor for poor outcomes in older adults. Identification of plasma markers may facilitate screening of sarcopenia. We previously reported that creatinine-to-cystatin C ratio is a simple marker of muscle mass. To further assess the clinical relevance of the creatinine-to-cystatin C ratio, we investigated its association with myosteatosis and physical performance.DesignObservational study.Setting and ParticipantsCross-sectional analysis of the dataset obtained from a Japanese population consisting of 1468 older (≥60 years of age) community residents.MethodsThe mean attenuation values of the skeletal muscle calculated from computed tomography images of the midthigh were used as an index of myosteatosis, while the cross-sectional area of the muscle was used as a proxy for muscle mass. Physical performance was assessed by 1-leg standing time.ResultsCreatinine-to-cystatin C ratio was positively associated with the cross-sectional area of muscle fiber-rich muscles, while it showed an inverse association with fat-rich muscle areas, resulting in the positive association between creatinine-to-cystatin C ratio and the mean attenuation value of the skeletal muscle [creatinine-to-cystatin C ratio quartiles (Q), Q1: 47.4 ± 4.8, Q2: 48.9 ± 4.4, Q3: 49.8 ± 4.1, Q4: 50.9 ± 3.7, P < .001]. The results of the linear regression analysis adjusted for major covariates (including muscle cross-sectional area) identified creatinine-to-cystatin C ratio as an independent determinant of the mean attenuation value (Q1: reference, Q2: β = 0.07, P = .019, Q3: β = 0.11, P < .001, Q4: β = 0.16, P < .001). Low creatinine-to-cystatin C ratio was independently associated with 1-leg standing time, although the association was attenuated substantially by adjusting for skeletal muscle cross-sectional area and mean attenuation value.Conclusion and ImplicationsCreatinine-to-cystatin C ratio was associated with myosteatosis in older adults, independent of the muscle mass. Creatinine-to-cystatin C ratio may serve as a convenient marker of sarcopenia.     

Predictors of In-Hospital Mortality in Older Patients With COVID-19: The COVIDAge Study

ObjectiveTo determine predictors of in-hospital mortality related to COVID-19 in older patients.DesignRetrospective cohort study.Setting and ParticipantsPatients aged 65 years and older hospitalized for a diagnosis of COVID-19.MethodsData from hospital admission were collected from the electronic medical records. Logistic regression and Cox proportional hazard models were used to predict mortality, our primary outcome. Variables at hospital admission were categorized according to the following domains: demographics, clinical history, comorbidities, previous treatment, clinical status, vital signs, clinical scales and scores, routine laboratory analysis, and imaging results.ResultsOf a total of 235 Caucasian patients, 43% were male, with a mean age of 86 ± 6.5 years. Seventy-six patients (32%) died. Nonsurvivors had a shorter number of days from initial symptoms to hospitalization (P = .007) and the length of stay in acute wards than survivors (P < .001). Similarly, they had a higher prevalence of heart failure (P = .044), peripheral artery disease (P = .009), crackles at clinical status (P < .001), respiratory rate (P = .005), oxygen support needs (P < .001), C-reactive protein (P < .001), bilateral and peripheral infiltrates on chest radiographs (P = .001), and a lower prevalence of headache (P = .009). Furthermore, nonsurvivors were more often frail (P < .001), with worse functional status (P < .001), higher comorbidity burden (P < .001), and delirium at admission (P = .007). A multivariable Cox model showed that male sex (HR 4.00, 95% CI 2.08-7.71, P < .001), increased fraction of inspired oxygen (HR 1.06, 95% CI 1.03-1.09, P < .001), and crackles (HR 2.42, 95% CI 1.15-6.06, P = .019) were the best predictors of mortality, while better functional status was protective (HR 0.98, 95% CI 0.97-0.99, P = .001).Conclusions and implicationsIn older patients hospitalized for COVID-19, male sex, crackles, a higher fraction of inspired oxygen, and functionality were independent risk factors of mortality. These routine parameters, and not differences in age, should be used to evaluate prognosis in older patients.     

Validity and Reliability of Tools to Measure Muscle Mass,Strength, and Physical Performance in Community-Dwelling Older People: A Systematic Review

BackgroundThis study critically appraises the measurement properties of tools to measure muscle mass, strength, and physical performance in community-dwelling older people. This can support the selection of a valid and reliable set of tools that is feasible for future screening and identification of sarcopenia.MethodsThe databases PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Cochrane were systematically searched (January 11, 2012). Studies were included if they investigated the measurement properties or feasibility, or both, of tools to measure muscle mass, strength, and physical performance in community-dwelling older people aged ≥60 years. The consensus-based standards for the selection of health status measurement instruments (COSMIN) checklist was used for quality appraisal of the studies.ResultsSixty-two publications were deemed eligible, including tools for muscle mass (n = 16), muscle strength (n = 15), and physical performance (n = 31). Magnetic resonance imaging, computed tomography, and a 4-compartment model were used as gold standards for muscle mass assessment. Other frequently used measures of muscle mass are dual-energy x-ray and the bioelectrical impedance (BIA); however, reliability data of the BIA are lacking. Handheld dynamometry and gait speed or a short physical performance battery provide a valid and reliable measurement of muscle strength and physical performance, respectively.ConclusionsIt can be concluded that several tools are available for valid and reliable measurements of muscle mass, strength, and performance in clinical settings. For a home-setting BIA, handheld dynamometry and gait speed or a short physical performance battery are the most valid, reliable, and feasible. The combination of selected instruments and its use for the screening and identification of sarcopenia in community-dwelling older people need further evaluation.     

Vitamin D and Muscle Function: Is There a Threshold in the Relation?

ObjectivesFirst, to determine the association between serum 25 hydroxyvitamin D (25OHD) concentration and muscle mass, strength, and performance. Second, to explore if there is a threshold in the association.DesignCross-sectional, single-center study.SettingThe central part of the Netherlands (52° Northern latitude).ParticipantsA total of 802 independently living men and postmenopausal women 40 to 80 years of age.MeasurementsHealth-related and lifestyle factors, including physical activity, 25OHD concentration, lean mass, handgrip strength, knee extension strength, and physical performance were determined.ResultsOverall, higher 25OHD level was significantly associated with higher lean mass (22.6 g per nmol/L, 95% CI 7.3–37.9), handgrip strength (0.020 kg per nmol/L, 95% CI 0.001–0.038), and physical performance (0.006 points per nmol/L, 95% CI 0.001–0.012), after adjustment for various confounders. This association was most pronounced below a 25OHD level of 60 nmol/L, with lean mass increase 79.6 g per nmol/L (95% CI 40.8–118.4, P < .01), handgrip strength 0.09 kg per nmol/L (95% CI 0.045–0.141, P < .01), and physical performance 0.02 points per nmol/L (95% CI 0.005–0.032, P < .01), and these significant associations attenuated to null above this threshold.ConclusionIn middle-aged men and (postmenopausal) women, a higher 25OHD level was significantly associated with higher lean mass, muscle strength, and performance. These associations were most pronounced below 60 nmol/L and absent above 60 nmol/L, indicating a ceiling effect.     

Physical Resilience in Daily Functioning Among Acutely Ill Hospitalized Older Adults: The Hospital-ADL Study

ObjectivesInsight into older adults’ physical resilience is needed to predict functional recovery after hospitalization. We assessed functional trajectories in response to acute illness and subsequent hospitalization and investigated baseline variables and dynamic variables associated with these trajectories.DesignProspective observational cohort study (Hospitalization-Associated Disability and impact on daily Life Study).Setting and ParticipantsThis study included 207 older adults (aged 79.8 ± 6.9 years, 49% female, 57% frail) acutely hospitalized in 6 Dutch hospitals.MethodsFunctional disability was assessed using the 15-item modified activities of daily living index retrospectively 2 weeks before admission, and prospectively from admission up to 3 months after discharge. Baseline variables including frailty, somatic, physical, and psychosocial factors were assessed at admission. Dynamic variables (step count, pain, fatigue, and fear of falling) were continuously or repeatedly assessed during hospitalization. We performed individual spline modeling using random effects. Baseline variables and within-person mean levels and variability in the dynamic variables were assessed as predictors of functional trajectories.ResultsFunctional disability significantly increased before admission and decreased from admission to 3 months post discharge. Frail participants had a significantly higher increase in functional disability before admission compared with nonfrail participants. Lower step count, higher pain scores, and higher within-person variability in fear of falling were significantly associated with higher increase in functional disability before admission. Higher within-person variability in fear of falling was associated with more recovery.Conclusions and ImplicationsOlder adults increase in functional disability before hospitalization and start to recover from admission onward. Frailty and dynamic variables are associated with a higher increase in functional disability after acute illness. Our findings give more insight into older adults’ physical resilience, which may improve the prediction of functional recovery and may improve therapeutic decision-making and rehabilitation strategies to improve functional recovery after acute hospitalization.     

Frailty,Sarcopenia, and Malnutrition Frequently (Co-)occur in Hospitalized Older Adults: A Systematic Review and Meta-analysis

ObjectivesThe purpose of this systematic review and meta-analysis was to summarize the prevalence of, and association between, physical frailty or sarcopenia and malnutrition in older hospitalized adults.DesignA systematic literature search was performed in 10 databases.Setting and ParticipantsArticles were selected that evaluated physical frailty or sarcopenia and malnutrition according to predefined criteria and cutoffs in older hospitalized patients.MeasuresData were pooled in a meta-analysis to evaluate the prevalence of prefrailty and frailty [together (pre-)frailty], sarcopenia, and risk of malnutrition and malnutrition [together (risk of) malnutrition], and the association between either (pre-)frailty or sarcopenia and (risk of) malnutrition.ResultsForty-seven articles with 18,039 patients (55% female) were included in the systematic review, and 39 articles (8868 patients, 62% female) were eligible for the meta-analysis. Pooling 11 studies (2725 patients) revealed that 84% [95% confidence interval (CI): 77%, 91%, I² = 98.4%] of patients were physically (pre-)frail. Pooling 15 studies (4014 patients) revealed that 37% (95% CI: 26%, 48%, I² = 98.6%) of patients had sarcopenia. Pooling 28 studies (7256 patients) revealed a prevalence of 66% (95% CI: 58%, 73%, I² = 98.6%) (risk of) malnutrition. Pooling 10 studies (2427 patients) revealed a high association [odds ratio (OR): 5.77 (95% CI: 3.88, 8.58), P < .0001, I² = 42.3%] and considerable overlap (49.7%) between physical (pre-)frailty and (risk of) malnutrition. Pooling 7 studies (2506 patients) revealed a high association [OR: 4.06 (95% CI: 2.43, 6.80), P < .0001, I² = 71.4%] and considerable overlap (41.6%) between sarcopenia and (risk of) malnutrition.Conclusions and ImplicationsThe association between and prevalence of (pre-)frailty or sarcopenia and (risk of) malnutrition in older hospitalized adults is substantial. About half of the hospitalized older adults suffer from 2 and perhaps 3 of these debilitating conditions. Therefore, standardized screening for these conditions at hospital admission is highly warranted to guide targeted nutritional and physical interventions.