UNASSIGNED: Muscle ultrasound has emerged as a promising method in the diagnostic work-up of sarcopenia. The objective of this scoping review was to explore the validity of muscle ultrasound against the latest sarcopenia definitions among older adults.
UNASSIGNED: We adhered to the PRISMA guidelines for scoping reviews. A systematic search of databases was performed by two independent reviewers. All articles comparing the performance of ultrasound to an internationally acknowledged sarcopenia definition among older adults (≥60 years) and published between 2019/01/01 (the year updated sarcopenia definitions were introduced) and 2023/11/15 were included. Data were extracted and collated by muscle and muscle parameters.
UNASSIGNED: Out of 2290 articles screened, six studies comprising 24 validity tests among a total of 1619 older adults (mean age 74.1 years, 52.2% female) were included. The validity tests investigated the rectus femoris (n = 7), biceps brachii (n = 5), gastrocnemius medialis (n = 4), tibialis anterior (n = 4), soleus (n = 3), and rectus abdominis (n = 1). The parameter muscle thickness (MT) (n = 14) was most commonly measured. The latest European and Asian sarcopenia definitions (EWGSOP2, AWGS2) were applied as reference standards in four validity tests each. None of the studies used the Sarcopenia Definition and Outcome Consortium (SDOC) criteria. The highest area under the curve AUC (0.92, 95% confidence interval [CI] 0.89-0.94) was found for the muscle thickness of the rectus femoris muscle. Due to substantial heterogeneity among the studies, pooling of data using a meta-analytic approach was not feasible.
UNASSIGNED: Limited number of studies have examined the validity of muscle ultrasound for diagnosing sarcopenia based on recent definitions among older adults. Thereby, muscle thickness of the rectus femoris showed promising results regarding validity. Further studies are needed to investigate the validity of key muscles and to validate muscle ultrasound among older hospitalized patients.

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia\'s pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway\'s role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

To discern the diagnostic accuracy between the updated diagnostic consensus of the Asian Working Group for Sarcopenia (AWGS) in 2019 (AWGS 2019) and the previous AWGS 2014 guidelines.
A prospective population-based cohort study.
The study included 731 older community-dwelling adults aged ≥ 65 years who participated in face-to-face interviews and were followed up for 11-year mortality until 31 Mar 2022.
We utilized a handgrip strength dynamometer to measure participants\' muscle strength, while their walking speed was determined by a timed 6-meter walk test at their usual pace. Additionally, muscle mass was measured using dual-energy X-ray absorptiometry scanning. Sarcopenia was defined as the presence of low muscle mass in combination with weakness and/or slowness both by AWGS 2014 and 2019 criteria.
The present study followed 731 participants (mean age 73.4 ± 5.4 years, men predominant 52.8%) over a period of 11 years, yielding 5927 person-years and 159 deaths. Prevalence of sarcopenia defined by AWGS 2019 and 2014 criteria were 8.5% and 6.8%, respectively. Sarcopenia defined by AWGS 2019 (HR 1.62, 95% CI 1.04-2.54, p=0.034) but not AWGS 2014 was significantly associated with mortality in community-living older adults after adjusting for potential confounders such as age, sex, education, drinking, disease burden and serum level of testosterone. The study also found that the AWGS 2019 criteria had a better model fitness than AWGS 2014 criteria in predicting mortality.
AWGS 2019 criteria outperformed AWGS 2014 in identifying sarcopenia risk and predicting mortality. Screening for sarcopenia in older adults may improve health outcomes by identifying those at increased mortality risk.

BACKGROUND: The aim of the study was to investigate a prevalence of sarcopenia in patients with gynecological cancer in accordance with current diagnostic criteria of sarcopenia.
METHODS: A series of 513 patients with gynecological cancer who were intended to newly receive initial or salvage treatment were recruited in a prospective study. Eligible patients were examined with dual energy X-ray absorptiometry and underwent handgrip strength test and the Short Physical Performance Battery before treatment. Sarcopenia was defined as both low skeletal muscle mass (skeletal muscle mass index) and low muscle strength (handgrip strength of <18.0 kg) or both low skeletal muscle mass index and low physical performance (Short Physical Performance Battery score of ≤9).
RESULTS: A total of 475 patients (92.6%) were completely assessed in this study. Eligible patients\' median age was 60 years (range: 29-89 years). Frequencies of patients with low skeletal muscle mass index, low hand grip strength and low Short Physical Performance Battery were 118 (24.8%), 70 (14.7%) and 80 (16.8%), respectively. Sarcopenia was finally identified in 45 patients (9.5%), which accounted for 38.1% of patients with low skeletal muscle mass index, 64.3% of the patients with low hand grip strength and 56.3% of the patients with low physical performance, respectively.
CONCLUSIONS: The prevalence of sarcopenia of 9.5% in patients with gynecological malignancy who were scheduled to newly receive an initial or a salvage treatment. A large-scale, nation-wide study might be planned to elucidate an accurate prevalence of sarcopenia among gynecologic cancer patients.

The number of patients on maintenance hemodialysis (HD) diagnosed with sarcopenia has been increasing through as individuals age. Recent focus is on the condition termed, \"dynapenia,\" which reduces only muscle function, as opposed to sarcopenia, which reduces both muscle mass and function. However, the association between dynapenia and cardio-cerebrovascular (CV) events in patients undergoing HD is largely unknown. The purpose of this study was to evaluate whether sarcopenia and dynapenia are associated with the onset of CV events in patients undergoing HD. We retrospectively analyzed 342 patients undergoing HD between January and December 2018. Patients who underwent HD thrice per week for > 3 months were included in the analysis. We adopted the Asian Working Group on Sarcopenia criteria for the diagnosis of sarcopenia and dynapenia. In this study, 244 patients undergoing HD were enrolled. The prevalence of sarcopenia was 38.5%. Sarcopenia was determined to be an independent contributor to CV events in patients undergoing HD. To investigate the clinical relevance of dynapenia in patients with HD, patients without sarcopenia were further divided into dynapenia and non-dynapenia groups. Among 150 patients without sarcopenia, 46 were diagnosed with dynapenia. In the Kaplan-Meier analysis, the rate of CV events was significantly different among the three groups in a stratified manner, with the highest rate in the sarcopenia group and the lowest rate in the non-sarco-dynapenia group. Both patients with sarcopenia and dynapenia had significantly increased CV events compared to those with non-sarco-dynapenia (HR 8.00; 95% CI 2.73-34.1; p < 0.0001 vs. HR 4.85; 95% CI 1.28-23.0; p < 0.02). Both sarcopenia and dynapenia resulted in significantly higher CV events than non-sarco-dynapenia in patients undergoing HD. Therefore, clinicians should evaluate muscle function in addition to muscle quantity to estimate CV events in patients undergoing HD.

OBJECTIVE: Sarcopenia is defined as a combination of low skeletal muscle mass index (SMI), weak muscle strength, and reduced physical function. Recently, many studies have reported that the creatinine/cystatin C ratio (Cr/CysC) is useful for evaluating muscle mass. We designed a cross-sectional study with separate model development and validation groups to develop a prediction equation to estimate bioimpedance analysis (BIA)-measured SMI with Cr/CysC.
METHODS: The current study was a retrospective cross-sectional study.
METHODS: The model development group included 908 subjects (288 men and 620 women) from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, and the validation group included 263 subjects (112 men and 151 women) from participants in the medical checkup program at the Anti-Aging Center in Ehime Prefecture.
METHODS: Multivariate regression analysis indicated that age, hemoglobin (Hb), body weight (BW), and Cr/CysC were independently associated with SMI in both men and women. The SMI prediction equation was developed as follows: Men:4.17-0.012×Age+1.24×(Cr/CysC)-0.0513×Hb+0.0598×BW Women:3.55-0.00765×Age+0.852×(Cr/CysC)-0.0627×Hb+0.0614×BW RESULTS: The SMI prediction equation was applied to the validation group and strong correlations were observed between the BIA-measured and predicted SMI (pSMI) in men and women. According to the receiver operator characteristic (ROC) analysis, the areas under the curve were 0.93 (specificity 89.0%, sensitivity 87.2%) among men and 0.88 (specificity 83.6%, sensitivity 79.6%) among women for using pSMI to identify low SMI in the model development group. The pSMI also indicated high accuracy in ROC analysis for low SMI in the validation group. The Bland-Altman plot regression showed good agreement between BIA-measured and pSMI.
CONCLUSIONS: Our new prediction equation to estimate SMI is easy to calculate in daily clinical practice and would be useful for diagnosing sarcopenia.

Sarcopenia is a disorder associated with age that reduces the mass of skeletal muscles, the strength of muscles, and/or physical activity. It increases the risk of fall incidence which can result in fractures, hospitalizations, limited movement, and considerably decreased quality of life. Hence, it is needed to explore candidate screening tools to evaluate sarcopenia in the initial phases. The reported studies have been revealed that the sensitivity and specificity of the Ishii score chart are higher. However, the Ishii score chart is principally based on the European Working Group on Sarcopenia in Older People (EWGSOP) consensus. Recently, the Asian Working Group for Sarcopenia (AWGS) 2019 consensus has updated its diagnostic criteria for sarcopenia,which was previously similar to the EWGSOP. Hence, it is necessary to determine whether the Ishii score chart is appropriate for use among the elderly population in China. The current study aimed to validate the precision of the Ishii score chart, within the Chinese old aged community to establish an effective model for the evaluation of sarcopenia.
The AWGS2019 sarcopenia diagnostic criteria were used as a standard, and among the elderly community, the accuracy of the Ishii score chart was determined by using indicators, including specificity, sensitivity, negative and positive predictive values, negative and positive likelihood ratios, Youden index, and receiver operating characteristic (ROC) curve.
In the elderly Chengdu community, the prevalence rate of sarcopenia was 18.38 %, 19.91 % for males and 16.91 % for females. The Ishii score chart predicts sarcopenia at an AUC value of 0.84 with 95 % confidence interval (CI), ranging between 0.80 and 0.89 for females, and at an AUC value of 0.81 with 95 % CI, ranging between 0.75 and 0.86 for males.According to the original cut-off, which was set at 120 points for females, the corresponding sensitivity was 46.91 % and the specificity was 93.22 %. The 105 cut-off points (original) set for males revealed a corresponding sensitivity of 64.94 % and the specificity of 85.46 %. However, the original cut-off value exhibited low sensitivity, hence, we selected a new cut-off value. With the new cut-off value, the sensitivity, specificity, positive and negative predictive values for sarcopenia were 75.31 %, 79.9 %, 43 %, and 94 % for females, and 70.65 %, 81.35 %, 49 %, and 92 % for males, respectively.
The Ishii score chart was used for the prediction of sarcopenia in the old-age people of the Chengdu community and the obtained results showed a high value of predictability. Hence, more than 95 and 102 points were suggested for males and females, accordingly which can set to be the diagnostic cut-off values for the prediction of sarcopenia.

Malnutrition and sarcopenia are prevalent and growing health issues in older populations. Early detection is important to implement proper interventions. However, little is known about malnutrition and sarcopenia in daycare facilities, the most dominant long-term care service. In this study, the prevalence of and factors associated with malnutrition and sarcopenia in older individuals who commute to community daycare facilities were evaluated. The cross-sectional study included 62 older individuals screened for malnutrition and sarcopenia on their first day in a daycare facility in Japan. Daily physical activity and basal diseases were also evaluated. According to Global Leadership Initiative on Malnutrition (GLIM) criteria, 40.3% (25/62) of patients were malnourished and 59.7% (37/62) were well nourished. The Asian Working Group for Sarcopenia 2019 evaluation found that 12.9% (8/62) of patients showed no sarcopenia, whereas 87.1% (54/62) had sarcopenia. The prevalence of well-nourished sarcopenic individuals was the highest (45.2% (28/62)), followed by malnourished sarcopenia individuals (40.3% (25/62)). All malnourished individuals were sarcopenic and 14.5% (9/62) were well nourished and nonsarcopenic. Daily physical activity was significantly lower among sarcopenic individuals. Subgroups showed no significant difference in comorbidities. The prevalence of malnutrition and sarcopenia was relatively high. Activity-related sarcopenia seemed to precede malnutrition. Early detection of malnutrition and sarcopenia in daycare facilities should be encouraged for early intervention.

UNASSIGNED: This 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.
UNASSIGNED: Patients (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.
UNASSIGNED: Sarcopenia 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).
UNASSIGNED: We 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.

OBJECTIVE: We evaluated several sarcopenia-related hormones, cytokines and uremic toxins to identify the humoral factors associated with sarcopenia and frailty in Japanese hemodialysis patients.
METHODS: Twenty Japanese patients aged ≥65 years who underwent maintenance hemodialysis therapy at Uonuma Kikan Hospital for more than 6 months were included in this retrospective cross-sectional study. Clinical data, including physical function and mental state, were obtained from the clinical records collected during the regular evaluation at the beginning of each hemodialysis therapy session, 3 days after the previous hemodialysis therapy. The diagnosis of sarcopenia and frailty was based on the Asian Working Group for Sarcopenia 2019 and the Japanese version of the Cardiovascular Health Study, respectively. The mental state of patients was evaluated using the Japanese version of the Patient Health Questionnaire 9 (J-PHQ-9).
RESULTS: In univariate analyses, plasma brain-derived neurotrophic factor (BDNF) levels were significantly lower in patients with severe sarcopenia and frailty. The plasma BDNF concentration was correlated with muscle strength and physical performances, such as the 6-m walk test, Short Physical Performance Battery and 5-time chair stand test. BDNF was also correlated with body weight, hemodialysis vintage, and serum levels of total protein and indoxyl sulfate but not with body mass index, appendicular skeletal muscle mass, serum interleukin 6 levels, or J-PHQ-9 scores. The odds ratio per 100 pg/mL of BDNF for the prevalence of frailty was 0.353.
CONCLUSIONS: BDNF is associated with decreased physical performance and the prevalence of severe sarcopenia and frailty in Japanese maintenance hemodialysis patients. Geriatr Gerontol Int 2021; 21: 27-33.