Sarcopenia Consensus Research Articles

Development and Validation of PRE-SARC (PREdiction of SARCopenia Risk in Community Older Adults) Sarcopenia Prediction Model

ObjectiveReliable identification of high-risk older adults who are likely to develop sarcopenia is essential to implement targeted preventive measures and follow-up. However, no sarcopenia prediction model is currently available for community use. Our objective was to develop and validate a risk prediction model for calculating the 1-year absolute risk of developing sarcopenia in an aging population. MethodsOne prospective population-based cohort of non-sarcopenic individuals aged 60 years or older were used for the development of a sarcopenia risk prediction model and model validation. Sarcopenia was defined according to the 2019 Asian Working Group for Sarcopenia consensus. Stepwise logistic regression was used to identify risk factors for sarcopenia incidence within a 1-year follow-up. Model performance was evaluated using the area under the receiver operating characteristics curve (AUROC) and calibration plot, respectively. ResultsThe development cohort included 1042 older adults, among whom 87 participants developed sarcopenia during a 1-year follow-up. The PRE-SARC (PREdiction of SARCopenia Risk in community older adults) model can accurately predict the 1-year risk of sarcopenia by using 7 easily accessible community-based predictors. The PRE-SARC model performed well in predicting sarcopenia, with an AUROC of 87% (95% CI, 0.83-0.90) and good calibration. Internal validation showed minimal optimism, with an adjusted AUROC of 0.85. The prediction score was categorized into 4 risk groups: low (0%-10%), moderate (>10%-20%), high (>20%-40%), and very high (>40%). The PRE-SARC model has been incorporated into an online risk calculator, which is freely accessible for daily clinical applications (https://sarcopeniariskprediction.shinyapps.io/dynnomapp/). ConclusionsIn community-dwelling individuals, the PRE-SARC model can accurately predict 1-year sarcopenia incidence. This model serves as a readily available and free accessible tool to identify older adults at high risk of sarcopenia, thereby facilitating personalized early preventive approaches and optimizing the utilization of health care resources.

The useful lean tissue and appendicular skeletal muscle mass indices related to physical performance in patients undergoing hemodialysis

BACKGROUND: Low muscle quantity commonly seen in patients undergoing hemodialysis (HD) is the key contributor of declined physical performance and increases the risk of morbidity and mortality. However, how to normalize muscle mass for operational criteria in this population remains unknown. OBJECTIVE: To identify the clinically useful whole body lean tissue mass (LTM) and appendicular skeletal muscle mass (ASM) indices pertinent to physical performance in patients undertaking HD. METHODS: Whole body LTM in 38 and ASM in 22 patients undergoing HD were measured by body composition monitor (BCM) and dual-energy X-ray absorptiometry (DXA), respectively. Physical performance was assessed by handgrip strength, the incremental shuttle walk test, sit-to-stand tests, gait speed, Short Physical Performance Battery and Duke Activity Status Index. Besides crude LTM and ASM, the other muscle indices were utilized normalizing for height, height squared, weight, body mass index (BMI), fat mass and body fat%. RESULTS: Regardless of BCM or DXA being used, the relationships between different muscle mass indices and physical function were not consistent. While the most useful LTM index which was strongly associated with physical function involved adjustment for height, the strongest (and most useful) ASM index was normalization for BMI. CONCLUSION: The superiority of adjustment for BMI or height (height2) recommended by international sarcopenia consensus is also suitable for patients undergoing HD. Patients’ BMI or fat mass should be considered in estimating prevalence of sarcopenia and evaluating relationship between muscle mass and physical performance.

DEVELOPMENT AND VALIDATION OF A RISK PREDICTION MODEL FOR SARCOPENIA IN COMMUNITY-DWELLING OLDER ADULTS

Abstract Reliable identification of older populations at high risk of sarcopenia is essential for initiating targeted preventive measures and follow-up, but no sarcopenia risk prediction model is available. Our objective was to develop and validate a prediction model for calculating the 1-year absolute risk of sarcopenia occurrence for older people in the community. The analytic samples for the prediction model derivation were conducted on data from one prospective population-based cohort. The main outcome was the development of sarcopenia within 1 year (defined by 2019 Asian Working Group for Sarcopenia consensus). Multivariate logistic regression analysis was conducted to examine those independent risk factors for sarcopenia and the sarcopenia risk-predicting model was developed using the R software. In the development cohort, 1042 non-sarcopenia residents were enrolled, of whom the mean age was 66.6±5.0 years, 631 participants were women, and 87 participants developed sarcopenia at the 12-month follow-up. The final model contains 7 risk factors-age, gender, BMI, low physical activity, malnutrition, pain, and calf circumference. The model showed excellent discrimination (AUROC 87%, 95% CI 0.83–0.90), calibration capability (slope 0.93) and clinical utility. Internal validation was conducted using 200 times bootstrapping technique and showed a stable discriminative ability (corrected AUROC of 0.85). High risk thresholds of 10% or more were able to identify high-risk individuals of sarcopenia, and low risk thresholds less than 2.5% were useful to rule out the likelihood of sarcopenia. In summary, the sarcopenia risk-predicting model for community-dwelling older people consists of 7 readily available predictors and has an excellent predictive ability.

Osteosarcopenia later in life: Prevalence and associated risk factors

The identification of risk factors for osteosarcopenia in older adults is important for planning preventative strategies in clinical practice. Therefore, our study aimed to investigate the prevalence and risk factors associated with osteosarcopenia in older adults using different diagnostic criteria. The sample included 171 community-dwelling older adults with a mean age of 79.4±5.9 years and mean body mass index of 25.67±4.70kg/m2. We analyzed sociodemographic, biomarkers, lifestyle, and health condition data from participants of the "Projeto Idosos - Goiânia" cohort study. The outcome osteosarcopenia was defined as the simultaneous occurrence of sarcopenia and osteopenia. Osteopenia was diagnosed by low lumbar spine bone mineral density (BMD) using dual-energy X-ray absorptiometry (DEXA). Sarcopenia was diagnosed using handgrip dynamometry and appendicular skeletal mass index assessed by DEXA following the criteria of the two European consensuses on sarcopenia (2010 and 2018). Two osteosarcopenia outcome variables were evaluated: OsteoSarc1 and OsteoSarc2 using the 2010 and 2018 European sarcopenia consensus criteria, respectively. Multivariate Poisson regression analysis was used to calculate the prevalence ratios (PRs). The prevalence of OsteoSarc1 and OsteoSarc2 were 12.8% and 7.2%, respectively, with no significant gender differences. OsteoSarc1 was associated with low potassium (PR: 3.39, 95% confidence interval [CI]: 1.10-10.43) and malnutrition (PR: 3.84, 95% CI: 1.78-8.30). OsteoSarc2 was associated with being ≥80 years (PR: 7.64, 95% CI: 1.57-37.07), >4 years of education (PR: 3.25, 95% CI: 1.03-10.22), alcohol consumption (PR: 2.41, 95% CI: 1.01-5.77), low potassium (PR: 2.22, 95% CI: 1.45-6.87), low serum vitamin D (PR: 4.47, 95% CI: 1.68-11.88), and malnutrition (PR: 5.00, 95% CI: 1.06-23.51). OsteoSarc1 had a higher prevalence. The risk factors associated with the two outcomes were malnutrition and potassium level, as well as other risk factors, such as alcohol consumption and low vitamin D level. These findings may contribute to the prevention or treatment of this health condition in older adults.

Indoxyl sulfate mediates low handgrip strength and is predictive of high hospitalization rates in patients with end-stage renal disease.

Sarcopenia has a higher occurrence rate in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD) than in the general population. Low handgrip strength-and not sarcopenia per se-is associated with clinical outcomes in patients with CKD, including cardiovascular mortality and hospitalization. The factors contributing to low handgrip strength are still unknown. Accordingly, this study aimed to determine whether uremic toxins influence low handgrip strength in patients with CKD. This cohort study lasted from August 2018 to January 2020. The participants were divided into three groups: the control group [estimated glomerular filtration rate (eGFR) ≥ 60 ml/min], an advanced CKD group (eGFR = 15-60 ml/min), and an ESRD group (under maintenance renal replacement therapy). All participants underwent handgrip strength measurement, dual-energy X-ray absorptiometry, and blood sampling for myokines (irisin, myostatin, and interleukin 6) and indoxyl sulfate. Sarcopenia was defined according to the Asian Working Group for Sarcopenia consensus as low appendicular skeletal muscle index (appendicular skeletal muscle/height2 of < 7.0 kg/m2 in men and < 5.4 kg/m2 in women) and low handgrip strength (< 28 kg in men and < 18 kg in women). Among the study participants (control: n = 16; CKD: n = 17; and ESRD: n = 42), the ESRD group had the highest prevalence of low handgrip strength (41.6 vs. 25% and 5.85% in the control and CKD groups, respectively; p < 0.05). The sarcopenia rate was similar among the groups (12.5, 17.6, and 19.5% for the control, CKD, and ESRD groups, respectively; p = 0.864). Low handgrip strength was associated with high hospitalization rates within the total study population during the 600-day follow-up period (p = 0.02). The predictions for cardiovascular mortality and hospitalization were similar among patients with and without sarcopenia (p = 0.190 and p = 0.094). The serum concentrations of indoxyl sulfate were higher in the ESRD group (227.29 ± 92.65 μM vs. 41.97 ± 43.96 μM and 6.54 ± 3.45 μM for the CKD and control groups, respectively; p < 0.05). Myokine concentrations were similar among groups. Indoxyl sulfate was associated with low handgrip strength in univariate and multivariate logistic regression models [univariate odds ratio (OR): 3.485, 95% confidence interval (CI): 1.372-8.852, p = 0.001; multivariate OR: 8.525, 95% CI: 1.807-40.207, p = 0.007]. Handgrip strength was lower in the patients with ESRD, and low handgrip strength was predictive of hospitalization in the total study population. Indoxyl sulfate contributed to low handgrip strength and counteracted the benefits of myokines in patients with CKD.

Diagnostic Value of Sarcopenia Computed Tomography Metrics for Older Patients with or without Cancers with Gastrointestinal Disorders.

The diagnostic utility of poor body composition measures in sarcopenia remains unclear. We hypothesize that the skeletal muscle gauge [combination of skeletal muscle index (SMI) and skeletal muscle density (SMD); SMG= SMI× SMD] would have significant diagnostic and predictive value in certain muscle regions and populations. Prospective cross-sectional study. We examined inpatients age ≥60years with or without cancer and with gastrointestinal disorders. We used computed tomography (CT) image metrics in the 12th thoracic (T12), third lumbar (L3), erector spinae muscle (ESM), and psoas muscle (PM) regions to establish correlations with the 2019 Asian Working Group for Sarcopenia Consensus and used receiver operating characteristic area under the curve (AUC) to compare differences between metrics. Associations between CT metrics and mortality were reported as relative risk after adjustments. We evaluated 385 patients (median age, 69.0years; 60.8% men) and found consistent trends in cancer (49.6%) and noncancer (50.4%) cohorts. SMG had a stronger correlation with muscle mass than SMD [mean rho: 0.68 (range, 0.59‒0.73) vs 0.39 (range, 0.28‒0.48); all P < .01] in T12, L3, and PM regions and a stronger correlation with muscle function than SMI [mean rho: 0.60 (range, 0.50‒0.77) vs 0.36 (range, 0.22‒0.58); all P < .05] in T12, ESM, and L3 regions. SMG outperformed SMI in diagnostic accuracy in all regions, particularly for L3 (AUC: 0.87‒0.88 vs 0.80‒0.82; both P < .05). PMG (PM gauge) and L3SMG did not differ, whereas EMG (ESM gauge) or T12SMG and L3SMG did (AUC: 0.80‒0.82 vs 0.87‒0.88; all P < .05). L3SMI, L3SMD, T12SMG, EMG, and PMG showed no association with 1-year cancer-related mortality after adjusting for confounders; however, L3SMG [relative risk= 0.92 (0.85‒0.99); P=.023) was. L3SMG covers all features of sarcopenia with more diagnostic value than other metrics, allowing a complete sarcopenia assessment with CT alone and not just in populations with cancer.

Dose-Dependent Association between Sarcopenia and Moderate-To-Severe Thoracic Vertebral Fragility Fracture in Older Adults

Introduction: Sarcopenia and vertebral fracture affect a large number of older adults and can be debilitating. However, the correlation between sarcopenia and vertebral fracture has not been well studied. Thus, this study investigates the correlation between vertebral fragility fracture and the severity of sarcopenia. Method: This cross-sectional study included 300 community-dwelling older adults with risk higher than 10-year probability of 3% for a hip fracture and 20% for a major osteoporotic fracture by FRAX score. Sarcopenia was defined according to the Asian Working Group for Sarcopenia consensus. Bone mineral density (BMD) was classified into normal or abnormal groups (T score ≤ −1.0) according to WHO criteria. Vertebral fracture was graded mild, moderate, and severe by a standardized semi-quantitative method. The association between sarcopenia and vertebral fragility fracture was investigated using a logistic regression model adjusted for confounding factors. Results: Compared with the normal BMD group, the abnormal BMD group had a significantly higher prevalence of sarcopenia (7.4 vs. 26.6%, p < 0.001), poorer muscle mass (p < 0.001), and poorer hand grip (p < 0.001). The prevalence of moderate-to-severe fracture was significantly different (p = 0.006) among severe sarcopenia (16.7%), sarcopenia (6.9%), and non-sarcopenia (3.7%) for thoracic vertebrae. In the logistical regression model adjusted for confounding factors, sarcopenia plus severe sarcopenia was identified as a risk factor for moderate-to-severe thoracic vertebral fragility fracture (odds ratio [OR] = 3.29, 95% CI: 1.23–8.78, p = 0.018). We further classified the participants into normal, sarcopenia, and severe sarcopenia and found that sarcopenia and severe sarcopenia had a dose-dependent association with prevalence of thoracic vertebral fragility fractures with ORs of 2.56 (95% CI: 0.66–9.91) and 4.04 (95% CI: 1.24–13.20), respectively; p for trend = 0.014. Conclusion: Sarcopenia is a potential risk factor for and has a dose-dependent association with moderate-to-severe thoracic fragility fracture in older adults at increased risk for fractures.

Exploring biomarkers of osteosarcopenia in older adults attending a frailty clinic

Osteosarcopenia is a new definitional approach that can increase the risk of falls and fractures in elderly compared with that of osteoporosis and sarcopenia alone. However, biomarkers for osteosarcopenia have not been well identified. Thus, we aimed to explore the biomarkers of osteosarcopenia, including bone, muscle, and geriatric markers. Outpatients attending a frailty clinic were enrolled in the study. Osteosarcopenia was defined as the coexistence of osteoporosis and sarcopenia. Osteoporosis was defined according to the criteria of the Japan Osteoporosis Society. Sarcopenia was defined according to the Asian Working Group for Sarcopenia consensus (2019). We selected 35 blood/serum pathological parameters, including bone, inflammation, nutritional, and aging markers for the study. Logistic regression analysis for osteosarcopenia was performed to explore the biomarkers of osteosarcopenia. Of the total 600 patients with a mean age of 76.6 years, 595 were enrolled in the registry during the study period. Logistic regression analysis for osteosarcopenia showed that elevated thyroid-stimulating hormone (TSH) (odds ratio [OR]:1.375; 95 % confidence interval [CI]: 1.092–1.731), bone-specific alkaline phosphatase (BAP) (OR: 1.059; 95 % CI: 1.002–1.120), and estimated glomerular filtration rate (eGFR) (OR: 1.029; 95 % CI: 1.007–1.053) increased the likelihood of osteosarcopenia. On the other hand, elevated 25-hydroxyvitamin D (25OHD) (OR: 0.905; 95 % CI: 0.841–0.974), blood urea nitrogen (BUN) (OR: 0.895; 95 % CI: 0.829–0.966) and K (OR: 0.241; 95 % CI: 0.081–0.717) decreased the likelihood of osteosarcopenia. It is worthwhile to examine these biomarkers for older adult outpatients attending a frailty clinic for screening osteosarcopenia. Further studies are needed to investigate the effects of other markers of bone metabolism.

Sarcopenia diagnosis in patients receiving hemodialysis: Agreement among different consensuses.

There are many consensuses to diagnose sarcopenia, and their agreement in patients receiving hemodialysis (HD) is not clear. We described the sarcopenia prevalence in patients receiving HD using different consensuses and analyzed their level of agreement. Sixty-seven patients (43 men, 55 ± 14.6 years) were evaluated for appendicular skeletal muscle mass using dual-energy x-ray absorptiometry and muscle strength using handgrip strength. Patients were classified according to different sarcopenia consensuses (European Working Group on Sarcopenia in Older People [EWGSOP], Revised EWGSOP [EWGSOP2], Foundation for the National Institutes of Health Project [FNIH], and Asian Working Group for Sarcopenia 2019 [AWGS2]). Kappa analysis identified the level of agreement. The prevalence of sarcopenia ranged from 1.5% to 11.9% depending on the sarcopenia consensus. The agreement between the different consensuses ranged from poor to almost perfect. FNIH and EWGSOP showed the lowest agreement (κ = 0.20; 95% CI, -0.14 to 0.54; P < 0.05), whereas EWGSOP2 and AWGS2 had the largest κ = 0.90 (95% CI, 0.71 to 1.00; P < 0.001). When stratified by age (≥60 years), the sarcopenia prevalence was higher in the older group (27% vs 2%; P = 0.004). In addition, male participants seemed to be more prone to sarcopenia compared with female counterparts, but this difference was not statistically confirmed (16% vs 4%; P = 0.242). The sarcopenia consensuses showed from poor to almost perfect agreement, which varied the sarcopenia prevalence rates in patients receiving HD. EWGSOP2 and AWGS2 showed the largest agreement.

Getting to grips with grip strength: A scoping review of patients mapped against sarcopenia consensus cut points

Purpose: Sarcopenia is a progressive and generalised skeletal muscle disorder that is associated with increased likelihood of adverse outcomes including falls and fractures. In 2019 a new European consensus document was published that allowed effective diagnosis of sarcopenia in a clinical setting (Cruz-Jentoft et al., 2019). As sarcopenia is a disorder that can be improved by physical interventions, it is important that physiotherapists working with older adults consider assessment for sarcopenia.

Relationship between malnutrition and possible sarcopenia in the AWGS 2019 consensus affecting mortality in hemodialysis patients: a prospective cohort study

BackgroundThe first objective of this study was to determine the relationship between muscle strength or physical performance and mortality, and the second objective was to show the relationship of Geriatric Nutritional Risk Index (GNRI) to muscle strength and physical performance decline.MethodsWe examined handgrip, the 5-times chair stand test, and GNRI in 635 maintenance hemodialysis patients and followed up for 72 months. Predictors for all-cause death were examined using Kaplan-Meier analysis and Cox proportional analysis. The relationship between possible sarcopenia and nutritional disorder (GNRI) was constructed receiver operating characteristic (ROC) curve. We used the Youden index to determine the optimal cutoff points for GNRI.ResultsThe multivariate Cox proportional hazard analysis revealed that the GNRI did not show any significance, although handgrip (HR 3.61, 95% CI 1.70–7.68, p < 0.001) and the 5-times chair stand test (HR 1.71 95% CI 1.01–2.90, p = 0.045) were significant predictors for mortality. On the evaluation of possible sarcopenia by handgrip strength, the area under curve (AUC) on ROC curve analysis were 0.68 (95% CI 0.64–0.72), and 5-chair stand, the AUC on ROC were 0.55 (95% CI 0.51–0.60). The cut-off value for the GNRI discriminating those at possible sarcopenia by handgrip strength based on the Youden index was 91.5.ConclusionsOur study suggests that the handgrip strength test of the AWGS 2019 sarcopenia consensus was a simple and useful tool to predict mortality in chronic hemodialysis patients. Furthermore, GNRI assessment can be a useful tool for screening before assessing possible sarcopenia when it is difficult to perform SARC-F to all patients.

Status of Constipation and Its Association with Sarcopenia in Older Adults: A Population-Based Cohort Study.

(1) Background: As the clinical relevance of constipation and sarcopenia is not well studied, we aimed to investigate the association between them in older adults. (2) Methods: A cross-sectional study was conducted on 1278 community-dwelling older adults in South Korea. The Rome IV criteria were used to identify patients with clinically defined constipation, while sarcopenia was defined by the Asian Working Group for Sarcopenia consensus. The cohort was classified into three groups: no constipation, self-reported constipation only, and clinically defined constipation. (3) Results: The presence of constipation was associated with sarcopenia and slow gait speed (p < 0.001). After adjustment for possible covariates, the association with sarcopenia attenuated, while that for slow gait speed persisted. In terms of geriatric parameters, both groups with clinically defined and self-reported constipation had a higher burden of cognitive impairment, IADL disability, and lower QOL scores (p < 0.05) compared with those without constipation. (4) Conclusions: Sarcopenia and slow gait speed associated with constipation in community-dwelling older adults. Individuals with self-reported constipation symptoms alone showed comparable sarcopenic and geriatric burden to those with clinically defined constipation. Clinical suspicion for possible co-existing sarcopenia is warranted in older patients with constipation.

According to Revised EWGSOP Sarcopenia Consensus Cut-Off Points, Low Physical Function Is Associated With Nutritional Status and Quality of Life in Maintenance Hemodialysis Patients

The aim of this study is to assess the association of nutritional status and quality of life with low physical function, according to the revised European Working Group on Sarcopenia in Older People (EWGSOP) - sarcopenia consensus cut-offs in maintenance hemodialysis patients. This is a cross-sectional study including patients on maintenance hemodialysis. Participants were submitted to a single evaluation of physical function, nutritional status, and quality of life. Handgrip strength, Short Physical Performance Battery (SPPB), sit-to-stand test, and gait speed were performed to evaluate physical function. Cut-offs proposed by the revised EWGSOP consensus were considered. Malnutrition Inflammation Score was used to assess nutritional status. Quality of life was assessed by the 36-Item Short Form Health Survey. Seventy-seven patients were enrolled, 64.9% male, mean age 55±14years. According to the cut-offs proposed by the most recent EWGSOP consensus, 55.8% of patients presented SPPB <8, 48.1% gait speed test ≤0.8m/seconds, sit-to-stand test >15seconds, and 39.0% handgrip strength <27 kg and <16kg for men and women, respectively. Malnutrition Inflammation Score was significantly associated with all physical function parameters, except gait speed, in receiver operating characteristic curve and logistic regression. The 36-Item Short Form Health Survey domains or component summary were associated with SSPB, gait speed, and handgrip strength in logistic regression. Poor nutritional status and quality of life are associated with low physical function (according to the cut-offs proposed by EWGSOP) in hemodialysis patients.

Prevalence of sarcopenia according to EWGSOP1 and EWGSOP2 in older adults and their associations with unfavorable health outcomes: a systematic review.

The European Working Group on Sarcopenia in Older People (EWGSOP) recently updated the definition and diagnostic criteria to assess sarcopenia, which can result in important changes in sarcopenia prevalence in older adults. To compare the prevalence of sarcopenia through the diagnostic criteria and definition proposed by the first (EWGSOP1) and recent (EWGSOP2) European consensus in older adults. We also aimed to evaluate which sarcopenia consensus is better associated with unfavorable health outcomes. The review followed PRISMA guidelines. Embase, Medline (PubMed), Scopus and Web of Science were searched from 2018 to February 2021. The systematic review protocol was registered at PROSPERO (CRD42020213303). The search, selection, and evaluation processes were done in a duplicate and independent manner. Of the 298 potentially eligible articles, 9 were included in this review. The prevalence of sarcopenia was 17.7% by EWGSOP1 and 11% by EWGSOP2. Evaluating all the studies, the sarcopenia prevalence ranged from 6.2 to 35.3% for the EWGSOP1, and from 3.2 to 26.3% for the EWGSOP2. Five studies have evaluated the association between the prevalence of sarcopenia (EWGSOP1 versus EWGSOP2) and unfavorable health outcomes, in which three studies showed that EWGSOP1 was better associated with increased risk of hospitalization and/or mortality. In comparison with EWGSOP1, the prevalence of sarcopenia in older adults decreased when diagnosed according to EWGSOP2. Based on limited evidence, EWGSOP2 seems to be worse for predicting unfavorable outcomes compared with EWGSOP1.

&lt;p&gt;Prevalence of Sarcopenia in Community-Dwelling Older Adults According to Simplified Algorithms for Sarcopenia Consensus Based on Asian Working Group for Sarcopenia&lt;/p&gt;

PurposeThis study sought to identify the prevalence of sarcopenia in community-dwelling Korean older adults and validate two simplified diagnostic algorithms based on the Asian Working Group for Sarcopenia (AWGS) algorithm for identifying sarcopenia.Patients and MethodsPatients (n = 338) aged ≥65 years participated in this cross-sectional study. Muscle strength was measured by hand grip strength, physical performance by gait speed, and muscle mass by the skeletal muscle mass index (SMI). Sarcopenia was assessed using the AWGS-recommended algorithm and two simplified algorithms (A and B). Algorithms A and B were validated with respect to the AWGS-recommended algorithm using the chi-square test, and the sensitivity and specificity were obtained.ResultsSarcopenia prevalence, determined using the AWGS-recommended algorithm, was 40.3% and 41.3% in men and women, respectively. The overall prevalence of sarcopenia was 41.0% by the AWGS-recommended algorithm, 37.6% by algorithm A, and 37.6% by algorithm B; 111 participants were diagnosed with sarcopenia using all three methods (p = 0.157).ConclusionWe established sarcopenia prevalence among rural community-dwelling adults in Korea and confirmed that the simplified algorithms were suitable for the identification of sarcopenia in rural community-dwelling older adults in Korea. Further studies are needed to assess whether these simplified algorithms are applicable to older Asian adults with functional and/or cognitive impairment and nursing home residents.

Unfavorable body composition and quality of life among community-dwelling middle-aged and older adults: What really matters?

ObjectiveTo evaluate the impact of individual components of unfavorable body composition and their combinations on quality of life (QoL) among middle-aged and older adults. MethodsData from 1779 participants (53.1 % female; mean age 63.9 ± 9.2 years) from the I-Lan Longitudinal Aging Study were analyzed in this study. Demographic characteristics of all participants and data from anthropometric measurements, functional assessments, dual-energy X-ray absorptiometry scans, and surveys of QoL were obtained. Low skeletal muscle mass was defined by the Asian Working Group of Sarcopenia consensus, and obesity was defined by waist circumference (WC), body fat percentage, or body mass index (BMI). QoL was assessed by the 12-Item Short Form Health Survey version 2, which was divided into the physical component summary (PCS) and mental component summary (MCS). The composite score was determined based on the items of unfavorable body composition. Independent associations between unfavorable body composition components and QoL were evaluated by the multivariate linear regression model. Z transformation was performed to facilitate evaluation between different components of body composition and their relationship with QoL. ResultsAll definitions of obesity were significantly associated with a lower PCS score (WC: β=-1.2, SE = 0.3, p < 0.001; body fat percentage: β=-1.0, SE = 0.3, p < 0.001; BMI: β=-0.9, SE = 0.3, p = 0.002 in the fully adjusted model). The PCS score decreased linearly as the composite score of unfavorable body composition increased, especially when obesity was defined by WC (score = 1: β=-0.7, SE = 0.4, p = 0.053, score = 2: β=-1.1, SE = 0.4, p = 0.008; score = 3: β=-2.4, SE = 1.0, p = 0.013). After Z transformation, obesity was significantly negatively associated with the PCS score (β=-0.9∼-0.2, SE = 0.1∼0.2, p values all less than 0.01). In contrast, a one-standard-deviation increase in WC was associated with a significantly higher MCS score (β = 0.3, SE = 0.1, p = 0.019). ConclusionsCommunity-dwelling middle-aged and older people with obesity had significantly lower PCS scores, and the effect was enhanced when low skeletal muscle mass or osteopenia/osteoporosis was present. Central obesity was the only unfavorable body composition parameter with negative effects on both the physical and the mental domains of QoL. Further longitudinal or intervention studies are needed to evaluate the impact on QoL of changes in body composition that occur with aging.

Sarcopenia in COPD: a systematic review and meta-analysis.

COPD is associated with a progressive loss of muscle mass and function. However, there is an unmet need to define and standardise methods to estimate the prevalence of sarcopenia in COPD patients.We performed a systematic review and meta-analysis of the prevalence of this extrapulmonary manifestation in COPD patients. We searched Embase, Medline (Ovid), CINAHL (EBSCO), Web of Science, Scopus and Google Scholar for studies published up to January 17, 2019, assessing sarcopenia in COPD patients based on low muscle mass and decreased muscle function. Interventional studies, in vitro experiments, protocols or reviews and meta-analyses were excluded. We estimated heterogeneity (I2) and assessed significance (Q) using a Chi-squared test for estimates obtained from random-effects models.4465 articles were initially identified. After removing the duplicates and applying the selection criteria, we reviewed 62 full-text articles. Finally, 10 articles (n=2565 COPD patients) were included in this systematic review and meta-analyses. Overall, the prevalence of sarcopenia in patients with COPD was 21.6% (95% CI 14.6-30.9%, I2=94%), ranging from 8% in population-based to 21% in clinic-based studies, and 63% in COPD patients residing in nursing homes.Sarcopenia is frequently observed in COPD patients, with varying prevalence across population settings. Sarcopenia in COPD should be assessed using standardised tests and cut-off points from sarcopenia consensus criteria for clinical practice and international comparisons.

Cut-off points for weight and body mass index adjusted bioimpedance analysis measurements of muscle mass

Low skeletal muscle mass (LMM) is a criterion to define both sarcopenia and malnutrition. Muscle mass varies with gender, height, weight or fat mass, and many indices of adjusted-muscle mass have been proposed. We aimed to find reference cut-off points of the skeletal muscle mass index (SMMI) adjusted for weight and body mass index (BMI) in Turkish population. Adults between 18 and 39years of age and community-dwelling older adults of 60-99years of age were included. Body composition was assessed with bioimpedance analysis (BIA). SMMI adjusted for weight and BMI were calculated [SMMI (weight) and SMMI (BMI)]. Muscle strength was assessed by hand-grip-strength with hand dynamometer. SMMI (weight) cut points were calculated from the healthy young adults' data as "mean SMMI-2 standard deviation (SD)". SMMI (BMI) cut points that predict low muscle strength were calculated with ROC analysis. To define low muscle strength, we used three currently suggested low muscle-strength thresholds, i.e., 32kg/22kg, 30kg/20kg, 26kg/16kg in males/females, respectively. 301 healthy young adults (187 male, 114 female) and 992 older people (308 male, 684 female) were included. LMM cut points for SMMI (weight) were 37.4% and 33.6% for males and females, respectively. SMMI (BMI) cut points that best predict the low grip-strength for 32kg/22kg; 30kg/20kg; 26kg/16kg thresholds were1.017kg/BMI and 0.677kg/BMI; 1.014kg/BMI and 0.710kg/BMI; 1.036kg/BMI and 0.770kg/BMI for males and females, respectively. Muscle-mass adjustment methods and techniques show diversity among the studies and have impact on the LMM cut-off points. This study presents population specific LMM thresholds for skeletal muscle mass adjusted for weight and BMI aiming to increase and improve the general applicability of the leading sarcopenia consensus definitions.

Systematic review: Prevalence of sarcopenia in ageing people using bioelectrical impedance analysis to assess muscle mass

ObjectiveTo examine the published scientific literature regarding the prevalence of sarcopenia in ageing people, with different diagnostic criteria, using bioelectrical impedance analysis (BIA) to assess the muscle mass. Methods and materialA systematic review was carried out following the PRISMA Statement. Three online databases were searched during May 2015 using pre-defined search terms. Prevalence studies of sarcopenia in well-defined populations of adults ≥50 years, using BIA to measure body composition, were selected. ResultsFifty-four articles were eligible for a full reading, and after a second round of exclusions a total of twelve studies met all the inclusion criteria. Eight were carried out in community-dwelling elderly people, two in nursing home residents, one in a convalescence and rehabilitation unit and one in hospitalized population. Five studies of sarcopenia's prevalence according to EWGSOP criteria were found, and in four of them the prevalence was higher in men. Prevalence of sarcopenia was higher in convalescence and rehabilitation units (77.6%), followed by elderly people living in nursing homes (32.8%). ConclusionsSarcopenia is highly prevalent in older individuals, especially in rehabilitation units. All the studies of prevalence carried out before the current sarcopenia consensus are studies to establish cutoff points of low muscle mass but they do not reflect sarcopenia's prevalence because they do not take into account muscle function.

Searching for a relevant definition of sarcopenia: results from the cross-sectional EPIDOS study.

With great interest, we read the recent paper by Dupuy et al. ‘Searching for a relevant definition of sarcopenia: results from the cross‐sectional EPIDemiologie de l'OSteoporose study’.1 The authors examined the prevalence of sarcopenia by using six different definitions of sarcopenia in 3025 non‐disabled women aged 75 years or older participating in the EPIDemiologie de l'OSteoporose study. The analysis revealed sarcopenia prevalence ranging from 3.3% to 20% depending on one of the six used definitions, where only 3.1% of the patients were identified as sarcopenic according to all of these definitions. This paper highlights the current problems in sarcopenia research in general and creates an academic discussion. Indeed, after Baumgartner et al. defined sarcopenia as muscle mass being two standard deviations below the normal appendicular muscle mass divided by height squared,2 a number of consensus definitions combining low muscle mass with parameters of physical performance (e.g. low gait speed or low hand grip strength) have been proposed.3, 4, 5 A wide range of diagnostic criteria of sarcopenia definition and diversity of the methods for muscle mass assessments leads per se to a high variety of the sarcopenia prevalences.2, 6, 7, 8 However, all of sarcopenia definitions are mainly directed to condition observed in elderly individuals. Nonetheless, loss of muscle mass has been observed beyond mere ageing‐related changes in a number of acute and chronic diseases. Evaluation of sarcopenia prevalence in specific cohorts of patients, for example, suffering from chronic kidney disease,9, 10 chronic heart failure,11 hip fractures,1 or hemiparetic stroke,12 is difficult because of lack of an appropriate disease‐related sarcopenia definition. Thus, in the present paper, the patients with walking or femoral neck fracture disabilities were excluded. This seems a clinical shortcoming as identification of sarcopenia especially in these patients and its prevention and or treatment might contribute a lot to the therapeutic success. Recently, two new terms for disease‐associated muscle wasting, such as myopenia and ‘muscle‐wasting disease’ have been suggested.13, 14 However, the principle difference between both terms and the sarcopenia consensus definitions is that these new terms do not reflect a reduction of muscle strength that contributes to physical disability.6, 15 The sarcopenia definition of Baumgartner et al. as well as early studies investigating the sarcopenia in community dwelling elderly considered only the reduced muscle mass but ignored functional decline. In the present study, the authors concluded that regardless of which of the six definitions of sarcopenia was applied, no increment in the predictive information on self‐reported physical difficulties could be obtained. If this holds true, the clinical relevance of adding functional capacity to the sarcopenia definition might be questioned. This study included only female subjects. In contrast, a previous study, examining sarcopenia in a cohort with 998 male and female subjects, revealed an association between functional impairment and poor health outcome in sarcopenic patients.16 Therefore, in our opinion, further work is needed to clarify if including of both muscle mass and measures of physical performance are more reliable for diagnosing of sarcopenia.