Sarcopenia: European consensus on definition and diagnosis: Report of the European Working Group on Sarcopenia in Older People

Mapping Knowledge Landscapes and Emerging Trends of Sarcopenic Obesity in Older Adults: A Bibliometric Analysis From 2004 to 2023

Background The prevalence of obesity in combination with sarcopenia, the age-related loss of muscle mass and strength or physical function, is on the rise among adults aged 65 years and older. A significant portion of this demographic now falls under the classification of sarcopenic obesity, a high-risk geriatric syndrome predominantly seen in an aging population vulnerable to compounded complications from both sarcopenia and obesity. It is essential to promptly evaluate the impact of academic research in this field, taking into account factors such as geographical regions, authors, journals, and institutions. Furthermore, exploring current topics and identifying potential areas that could inspire future researchers to conduct additional studies is crucial for advancing overall health in this population. Methodology A search was conducted in the Web of Science Core Collection database to identify English language articles and reviews focusing on sarcopenic obesity in older adults, published between January 1, 2004, and December 31, 2023. Bibliometric analysis was performed using VOSviewer (v.1.6.18) and CiteSpace (v.6.1.R2). Results A total of 985 original English-language articles were collected, consisting of 783 articles and 202 reviews. The volume of research publications in this field has shown significant growth since 2012. The United States leads in contributions, with 239 articles (24.3% of the total) and the highest number of citations at 18,403, along with the highest total link strength. The University of Melbourne in Australia stands out with 25 published articles (2.5% of the total). University of Verona in Italy has the most citations at 9,405, and Monash University in Australia has the highest total link strength at 53. Among prolific authors, John A. Batsis from Duke University is the most productive with 24 articles (2.4% of the total). The journal "Nutrients" has the most articles on sarcopenic obesity in older adults, publishing 54 articles (5.5% of the total). Key topics in this area include sarcopenia, obesity, sarcopenic obesity, and elderly. Recent interventions focus on "nutrition" and "exercise" for sarcopenic obesity in older adults. Conclusions Research on sarcopenic obesity in older adults has seen significant growth on a global scale from 2004 to 2023, indicating a promising area for further study with potential benefits from current advancements. Although academic inquiries have shed light on various aspects of sarcopenic obesity in older adults, there remains a noticeable dearth of clinical research and evidence-based medicine on the effective management of this condition in elderly individuals. Future studies could focus on developing tailored interventions for older adults with sarcopenic obesity.

Start with muscle mass or muscle strength in diagnosis and management of sarcopenia? A systematic review of guidance documents

BACKGROUND AND OBJECTIVES

Sarcopenia has garnered extensive attention in clinical practice since its high prevalence and significant impact on clinical outcomes. Multiple organizations have published guidance documents on sarcopenia, offering evidence-based recommendations for clinical practice and/or research. We aimed to appraise the methodological quality of the included documents and synthesize available recommendations for the screening, diagnosis, and intervention of sarcopenia.

METHODS AND STUDY DESIGN

We conducted a search on PubMed, Embase, Scopus, Cochrane Library, China National Knowledge Infrastructure, guideline database, and guideline organizations and professional societies websites for clinical practices, consensus statements and position papers in terms of sarcopenia, muscle atrophy or muscle loss published before April 17, 2023. The AGREE II instrument was used by three independent reviewers to assess the methodological quality of these documents.

RESULTS

Thirty-six guidance documents published between 2010 and 2023 were included. Seven documents fulfilled ≥ 50% of all the AGREE II domains. Seven underwent a Delphi process and six graded the strength of the recommendations. The process of screening (n=21), early diagnosis of sarcopenia (n=12), diagnosis of sarcopenia and severe sarcopenia (n=10), and management (n=21) were increasingly recommended. SARC-F (n=14) was the most recommended screening tool, and the assessment of muscle function was considered the first step in diagnosing sarcopenia. The management strategy for both age-related and disease-related sarcopenia mainly focused on exercise and nutrition intervention.

CONCLUSIONS

The guidance documents have provided referential recommendations that have great guiding significance. But the inconsistency in recommendations and variation in methodological rigour suggests that high-quality evidence is lacking yet.

Causal associations between sarcopenia-related traits and intervertebral disc degeneration: a two-sample mendelian randomization analysis

BACKGROUND

Sarcopenia (SP) and intervertebral disc degeneration (IVDD) have a higher incidence in the elderly population. Previous studies have indicated a potential association between SP and IVDD. The objective of this study is to elucidate the potential causal relationship between sarcopenia-related traits and IVDD through Two-sample Mendelian randomization (MR) analysis.

METHODS

We utilized a genome-wide association study conducted on the European population to collect aggregated data on sarcopenia and IVDD. Inverse variance weighting was primarily employed, supplemented by MR Egger, weighted median, simple model, and weighted model methods. Additionally, sensitivity analysis was performed to assess the robustness of the findings.

RESULTS

Appendicular lean mass is positively associated with "Other intervertebral disc disorders" (OIDD) and "Prolapsed or slipped disc" (POSD) (OIDD: p = 0.002, OR = 1.120; POSD: p < 0.001, OR = 1.003), while grip strength (GS) is positively associated with POSD (left: p = 0.004, OR = 1.008; right: p < 0.001, OR = 1.010). It is worth mentioning that walking pace has significant causal relationship with "Low back pain" (LBP), "Lower back pain or/and sciatica" (LBPOAS), "Sciatica with lumbago" (SWL) and OIDD (LBP: p < 0.001, OR = 0.204; LBPOAS: p < 0.001, OR = 0.278; SWL: p = 0.003, OR = 0.249; OIDD: p < 0.001, OR = 0.256).

CONCLUSION

The present study revealed the causal relationship between SP-related traits and IVDD and recommended to prevent and treat sarcopenia as a means of preventing IVDD in clinic practice.

Cutoff values for appendicular skeletal muscle mass using dual-energy x-ray absorptiometry in a reference group of Turkish adults

BACKGROUND

The aim of this study is to determine cutoff values for different appendicular skeletal muscle mass index (ASMI) methods measured by dual-energy x-ray absorptiometry (DXA) in a reference group of the Turkish population.

METHODS

Body composition analyses were performed with DXA, and appendicular skeletal muscle mass (ASM) was adjusted to body size as ASMI using height squared (ASM/ht2), weight (ASM/wt), and body mass index (BMI) (ASM/BMI). Sex-specific cutoff values were obtained as 1 and 2 standard deviations (SDs) below the mean values of ASM/ht2, ASM/wt, and ASM/BMI.

RESULTS

A total of 207 (106 women and 101 men) healthy adults were enrolled. Sex-specific cutoff values based on 1 SD below the mean values of ASM, ASM/ht2, ASM/BMI, and ASM/wt were 14.44, 5.45, 0.61, and 24.07 in women and 22.63, 7.22, 0.90, and 29.04 in men, respectively; 2 SDs below the mean values of ASM, ASM/ht2, ASM/BMI, and ASM/wt were 11.96, 4.65, 0.51, and 21.75 in women and 19.26, 6.40, 0.78, and 26.55 in men, respectively. ASM, ASM/BMI, ASM/ht2, and ASM/wt were statistically significant positively correlated with handgrip strength (r = 0.81, r = 0.78, r = 0.73, and r = 0.67, respectively; P < 0.001).

CONCLUSION

In this study, ASM/BMI was found to be the most suitable ASM adjustment method to predict muscle strength.

Agreement and diagnostic differences among three definitions of sarcopenia in patients with chronic hepatitis C

BACKGROUND

There is neither a gold standard definition nor a universal consensus to diagnose sarcopenia in patients with chronic hepatitis C. Thus, we aimed to compare the prevalence of sarcopenia and the agreement and discrepancies between European Working Group on Sarcopenia in Older People (EWGSOP1), EWGSOP2, and Foundation for the National Institutes of Health Biomarkers Consortium Sarcopenia Project (FNIH) definitions in chronic hepatitis C.

METHODS

Dual-energy x-ray absorptiometry was used to assess muscle mass by quantifying appendicular lean mass (ALM) adjusted for squared height (ALM/ht2) or for body mass index (ALMBMI). Muscle function was evaluated by handgrip strength. Subjective Global Assessment was used to assess the nutrition status.

RESULTS

This cross-sectional study included 103 outpatients (mean age, 50.6 ± 11.3 years; 33.0% with compensated cirrhosis). Sarcopenia prevalence was 8.7%, 9.7%, and 9.7%, according to EWGSOP1, EWGSOP2, and FNIH definitions, respectively. There was neither a sex- nor a liver disease severity-specific difference in the prevalence of sarcopenia between the criteria applied. Sixteen (15.5%) patients fulfilled at least one of these criteria, and 3 out of 16 (18.8%) simultaneously had sarcopenia by consensus of the three criteria. Sarcopenic obesity was identified in 9 out of 16 (56.3%) patients, and 6 out of 9 (66.7%) of these only met FNIH consensus.

CONCLUSIONS

In patients without cirrhosis or with compensated cirrhosis, and with chronic hepatitis C, the agreement between EWGSOP1 and EWGSOP2 classifications was substantial for sarcopenia diagnosis. Concerning EWGSOP and FNIH criteria, a fair agreement and limited overlap were found in these patients.

Sarcopenia diagnosis in patients with colorectal cancer: a review of computed tomography-based assessments and emerging ways to enhance practicality

Traditionally, cancer treatment has focused on the stages of the disease; however, recent studies have highlighted the importance of considering the overall health status of patients in the prognosis of cancer. Loss of skeletal muscle, known as sarcopenia, has been found to significantly affect outcomes in many different types of cancers, including colorectal cancer. In this review, we discuss the guidelines for diagnosing sarcopenia, with a specific focus on CT-based assessments. Many groups worldwide, including those in Europe and Asia, have introduced their own diagnostic guidelines for sarcopenia. Seemingly similar yet subtle discrepancies, particularly in the cutoff values used, limit the use of these guidelines in the general population, warranting a more universal guideline. Although CT-based measurements, such as skeletal muscle index and radiodensity, have shown promise in predicting outcomes, the lack of standardized values in these measurements hinders their universal adoption. To overcome these limitations, innovative approaches are being developed to assess changes in muscle mass trajectories and introduce new indices, such as skeletal and appendicular muscle gauges. Additionally, machine learning models have shown superior performance in predicting sarcopenic status, providing an alternative to CT-based diagnosis, particularly after surgery. CT has tremendous benefits and a significant role in visually as well as quantitatively retrieving information on patient body composition. In order to compensate for the limitation of standard cutoff value, 3-dimensional analysis of the CT, artificial intelligence-based body composition analysis, as well as machine learning algorithms for data interpretation and analysis have been proposed and are being utilized. In conclusion, despite the varying definitions of sarcopenia, CT-based measurements coupled with machine-learning models are promising for evaluating patients with cancer. Standardization efforts can improve diagnostic accuracy, reduce the reliance on CT examinations, and make sarcopenia assessments more accessible in clinical settings.

Senolytic treatment does not mitigate oxidative stress-induced muscle atrophy but improves muscle force generation in CuZn superoxide dismutase knockout mice

Oxidative stress is associated with tissue dysfunctions that can lead to reduced health. Prior work has shown that oxidative stress contributes to both muscle atrophy and cellular senescence, which is a hallmark of aging that may drive in muscle atrophy and muscle contractile dysfunction. The purpose of the study was to test the hypothesis that cellular senescence contributes to muscle atrophy or weakness. To increase potential senescence in skeletal muscle, we used a model of oxidative stress-induced muscle frailty, the CuZn superoxide dismutase knockout (Sod1KO) mouse. We treated 6-month-old wildtype (WT) and Sod1KO mice with either vehicle or a senolytic treatment of combined dasatinib (5 mg/kg) + quercetin (50 mg/kg) (D + Q) for 3 consecutive days every 15 days. We continued treatment for 7 months and sacrificed the mice at 13 months of age. Treatment with D + Q did not preserve muscle mass, reduce NMJ fragmentation, or alter muscle protein synthesis in Sod1KO mice when compared to the vehicle-treated group. However, we observed an improvement in muscle-specific force generation in Sod1KO mice treated with D + Q when compared to Sod1KO-vehicle mice. Overall, these data suggest that reducing cellular senescence via D + Q is not sufficient to mitigate loss of muscle mass in a mouse model of oxidative stress-induced muscle frailty but may mitigate some aspects of oxidative stress-induced muscle dysfunction.

Obstructive sleep apnea (OSA) is associated with increased risk of early-onset sarcopenia and sarcopenic obesity: Results from NHANES 2015-2018

OBJECTIVE

This study aims to estimate the prevalence of early-onset sarcopenia and sarcopenic obesity in the United States and its relative risk due to obstructive sleep apnea (OSA).

METHODS

Data in this cross-sectional study were extracted from the National Health and Nutritional Examination Survey (NHANES) 2015-2018. Weighted multistage stratified probability sampling design was considered to estimate the prevalence of early-onset sarcopenia and sarcopenic obesity. Weighted multivariable logistic regression analyses and weighted multivariable mediation models were performed to evaluate the association between OSA and early-onset sarcopenia.

RESULTS

The prevalence of early-onset sarcopenia and early-onset sarcopenic obesity was estimated to be 5.5% and 4.6%, respectively. A higher prevalence of sarcopenia (12% V.S. 5.5%, P < 0.01) and sarcopenic obesity (10.3% V.S. 4.0%, P < 0.01) was observed among participants with OSA than those without OSA. Multivariable logistic regression models suggested that participants with OSA had higher odds ratios of suffering from early-onset sarcopenia [Odds Ratio (OR): 1.5, 95% confidence interval (CI):1.1-2.7] and early-onset sarcopenic obesity [OR: 1.8, 95% CI: 1.1-3.1] after adjusting for potential confounding variables. Mediation analyses suggested serum chronic reaction protein (CRP) mediated 23.7% (P < 0.01) & 26.2% (P < 0.01), homeostasis model assessment insulin resistance index (HOMA-IR) mediated 24.8% (P < 0.01) & 20.7% (P < 0.05), body mass index (BMI) mediated 46.4% (P < 0.05) & 49.9% (P < 0.01), HEI-2015 mediated 23.3% (P < 0.01) & 25.6% (P < 0.01), and Vitamin D mediated 7.5% (P < 0.01) & 8.5% (P < 0.01) of the potential effects of OSA on early-onset sarcopenia and sarcopenic obesity, respectively.

CONCLUSION

Early-onset sarcopenia and sarcopenic obesity were prevalent among young adults in the US. OSA is a significant independent risk factor and may induce muscle loss by unhealthy diet habits, higher BMI, chronic inflammation, insulin resistance, and Vitamin D. It was essential for clinicians to arrange appropriate screening and interventions for patients with OSA to prevent muscle loss as early as possible.

Patient-reported difficulty in activities of daily living and corresponding muscle weakness in elderly patients undergoing haemodialysis

AIM

Patients undergoing haemodialysis have reduced muscle strength and impaired activities of daily living (ADL). We examined possible relationship between difficult ADL and corresponding muscle weakness in elderly haemodialysis patients.

METHODS

This was a single-centre, cross-sectional study. Patient-reported ADL difficulty was examined using a questionnaire in six ADL using upper limbs (eating, grooming and dressing) and lower limbs (bathing, toileting and locomotion). We measured six muscle strengths by dynamometers of shoulder flexion, shoulder abduction, elbow flexion, handgrip, hip abduction and knee extension. The muscle strength with the lowest Z-score was considered as the weakest muscle strength for the patient.

RESULTS

The six scores of ADL difficulty were all inversely associated with the six muscle strengths in the 81 total participants of whom 71 individuals (87.7%) had any ADL difficulty. Among the six measurements of muscle strength, handgrip strength showed the highest associations with all ADL difficulties. In 25 patients who perceived that the most difficult ADL was an activity using upper limbs, the common weakest muscle strengths were the hip abduction, handgrip and elbow flexion. In 44 patients who perceived that the most difficult ADL was an activity using lower limbs, knee extension was the most prevalent weakest muscle strength.

CONCLUSION

This study suggested preferential relationship between the most difficult ADL and corresponding muscle weakness in elderly haemodialysis patients. This finding may be useful in prevention and treatment.

Associations of Preoperative Nutritional Status and Sarcopenia With Mortality in Patients With Abdominal Aortic Aneurysm After Open and Endovascular Abdominal Aortic Aneurysm Repair: A Retrospective Study

OBJECTIVE

The effect of preoperative malnutrition and sarcopenia on outcomes in patients with abdominal aortic aneurysm (AAA) after open surgical repair (OSR) and endovascular abdominal aortic aneurysm repair is undefined. The authors conducted the study to address this issue in this population.

DESIGN

A retrospective observational study.

SETTING

A large tertiary hospital.

PARTICIPANTS

Patients with AAA who underwent OSR and endovascular aneurysm repair (EVAR).

INTERVENTIONS

Evaluation of nutritional status (Nutritional Risk Screening 2002 [NRS 2002] and the Controlling Nutritional Status [CONUT] scores), muscle size (skeletal muscle index), and postoperative parameters.

MEASUREMENTS AND MAIN RESULTS

A total of 199 patients were reviewed from January 2020 to December 2022. Patients weew categorized into group A (CONUT <4) and group B (CONUT ≥4) based on whether their CONUT scores were less than 4. The mortality (p = 0.004) and the incidence of Clavien-Dindo class III complications (p = 0.007) in group B were higher than those in group A. CONUT score was an independent risk factor for midterm mortality (hazard ratio 1.329; 95% CI, 1.104-1.697; p = 0.002) and Clavien-Dindo class III complications (odds ratio 1.225; 95% CI, 1.012-1.482; p = 0.037) according to univariate and multivariate analyses, whereas NRS 2002 score and sarcopenia were not. Kaplan-Meier curves showed a lower midterm survival rate in group B (log-rank p < 0.001).

CONCLUSION

In patients with AAA undergoing OSR or EVAR, a CONUT score ≥4 was associated with increased Clavien-Dindo class III complications and mortality. Preoperative nutritional status should be evaluated and optimized in this high-risk population.

Frontiers in sarcopenia: Advancements in diagnostics, molecular mechanisms, and therapeutic strategies

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.

Examining the presence of sarcopenia in women with rheumatoid arthritis: Case-control study

INTRODUCTION

The aim of this study was to compare the frequency of sarcopenia, functional status, fear-avoidance behaviors, biopsychosocial status and quality of life in RA women with healthy controls.

METHODS

25 RA women and 25 healthy women were included in the study. Definition of sarcopenia was assessed using parameters recommended by the European Working Group on Sarcopenia (EWGSOP): Bioimpedance analysis for muscle mass (body fat ratio, skeletal muscle mass, skeletal muscle mass index); grip and knee extension strength for muscle strength and 4-m course gait speed test for physical performance was applied. Functional status was evaluated with the Health Assessment Questionnaire (HAQ), fear-avoidance behaviors with the Tampa Kinesiophobia Scale (TKS), biopsychosocial status with the Biopsychosocial Questionnaire (BETY-BQ), and quality of life with Short Form-36 (SF-36).

RESULTS

While none of the healthy women had sarcopenia, severe sarcopenia was detected in 7 (28%) of the women with RA. When RA and healthy groups were compared; skeletal muscle mass (p: 0,004); skeletal muscle mass index (p: 0,011); grip strength-right (p:0.001) and left (p:0.001); knee extension strength-right (p:0.001) and left (p:0.001), 4-m course gait speed test (p:0.001), HAQ (p:0.001), TKS (p:0.001), BETY-BQ (p:0.001), SF-36 physical (p:0.001) ve mental component (p:0.001) results were significant in favor of the healthy group while there was no difference in body fat ratio (p>0.05).

CONCLUSION

In women with RA, the frequency of sarcopenia is higher, and functional status, fear-avoidance behaviors, biopsychosocial status and quality of life are worse than healthy.

Accuracy of a portable lower-limb muscle strength measuring device with a training function

[Purpose] Quadriceps muscle strength is essential for daily living activities. Therefore, we developed a compact and simple lower limb muscle strength measuring device (LocomoScan [LCS]). This study aimed to compare LCS with other instruments to analyze its simplicity, reproducibility, and accuracy. [Participants and Methods] One hundred and four healthy university students (56 males and 48 females) were included in the study. The knee extension force was measured using LCS, and the knee extension torque was measured using other devices (Cybex). In addition, lower leg muscle mass was measured using a body composition meter. The reproducibility of LCS and the correlation between the knee extension torque and lower leg muscle mass were evaluated. [Results] The measurement reproducibility of LCS was significantly higher. The knee extension force confirmed the proportional relative reliability of Cybex with knee extension torque. A relationship between knee extension force and lower limb muscle mass was also observed, indicating that muscle mass cannot be estimated as muscle strength. [Conclusion] The high reproducibility of the knee extension force measurement using LCS demonstrates its potential as a portable alternative instrument for muscle strength measurement in clinical practice. Therefore, LCS device is a simple and effective tool for assessing muscle strength.

Metals accumulation affects bone and muscle in osteoporotic patients: A pilot study

Osteoporosis is the most common bone disease, characterized by decreased bone mineral density (BMD) and often associated to decreased muscle mass and function. Metal exposure plays a role in the pathophysiology of osteoporosis and affects also muscle quality. The aim of this study was to assess the association between metal levels in bone and muscle samples and the degeneration of these tissues. A total of 58 subjects (30 male and 28 female) was enrolled and classified in osteoporotic (OP, n = 8), osteopenic (Ope, n = 30) and healthy (CTR, n = 20) subjects, according to BMD measures. Femoral head bone samples and vastus lateralis muscle samples were collected during hip arthroplasty surgeries. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis showed increased levels of Al, Cd and Pb in OP and Ope bone tissue compared to CTR subjects (p = 0.04, p = 0.005 and p = 0.01, respectively). Whereas, increased levels of Co, Cd and Pb were measured in OP and Ope muscle tissues, compared to CTRs (p < 0.001, p = 0.02 and p = 0.01, respectively). In addition, Al, Cd and Pb levels in bone and Cd and Co levels in muscle were negatively correlated with BMD. A negative association among Co, Cd, Cr and Hg levels and muscle fibers diameter was also observed in muscle tissues. This study assessed that metal exposure can affects bone and muscle tissue quality and may contribute to the onset and progression of musculoskeletal diseases such as osteoporosis. Therefore, it is important to implement metal exposure assessment and their impact on disease development, in order to manage and prevent metal accumulation effects on bone and muscle quality.

A perspective on muscle phenotyping in musculoskeletal research

Musculoskeletal research should synergistically investigate bone and muscle to inform approaches for maintaining mobility and to avoid bone fractures. The relationship between sarcopenia and osteoporosis, integrated in the term 'osteosarcopenia', is underscored by the close association shown between these two conditions in many studies, whereby one entity emerges as a predictor of the other. In a recent workshop of Working Group (WG) 2 of the EU Cooperation in Science and Technology (COST) Action 'Genomics of MusculoSkeletal traits Translational Network' (GEMSTONE) consortium (CA18139), muscle characterization was highlighted as being important, but currently under-recognized in the musculoskeletal field. Here, we summarize the opinions of the Consortium and research questions around translational and clinical musculoskeletal research, discussing muscle phenotyping in human experimental research and in two animal models: zebrafish and mouse.

Clinical outcomes of multidimensional association of type 2 diabetes mellitus, COVID-19 and sarcopenia: an algorithm and scoping systematic evaluation

BACKGROUND

The aim of this study was to provide a scoping and comprehensive review for the clinical outcomes from the cross-link of Type 2 diabetes mellitus (T2DM), COVID-19, and sarcopenia.

METHODS

By using PRISMA guidelines and searching through different databases that could provide findings of evidence on the association of T2DM, COVID-19, and sarcopenia.

RESULTS

Thirty-three studies reported a relationship between sarcopenia with T2DM, twenty-one studies reported the prognosis COVID-19 in patients with T2DM, ten studies reported the prognosis of COVID-19 in patients with sarcopenia, five studies discussed the outcomes of sarcopenia in patients with COVID-19, and one study reported sarcopenia outcomes in the presence of T2DM and COVID-19.

CONCLUSION

There is an obvious multidimensional relationship between T2DM, COVID-19 and sarcopenia which can cause prejudicial effects, poor prognosis, prolonged hospitalisation, lowered quality of life and a higher mortality rate during the current COVID-19 pandemic.

Association of body composition and survival in patients with locally advanced breast cancer: a historical cohort study

BACKGROUND

Altered body composition has been attributed to major health problems globally, particularly in patients with cancer. To date, there have not been sufficient indices for body compositions in predicting the survival of locally advanced breast cancer (LABC).

PURPOSE

To assess the association between body composition and overall survival (OS) as well as disease-free survival (DFS) in patients with LABC.

MATERIAL AND METHODS

A retrospective study was conducted of patients with LABC diagnosed between 2010 and 2018. Body composition parameters, including skeletal muscle and adiposity parameters, were measured using computed tomography at the L3 vertebra using in-house software developed by MATLAB and freeware Python 3.6.13. The association between body composition and OS and DFS were analyzed using a log-rank test and multivariate Cox-proportional hazard regression.

RESULTS

Of 199 patients, 72 (36%) died during the follow-up period (range = 3.8-150.7 months). Median survival was 101 months. Low visceral-to-subcutaneous ratio ≤0.3 (adjusted hazard ratio [aHR] = 2.57, 95% confidence interval [CI] = 1.51-4.37; aHR = 2.46, 95% CI = 1.33-4.56), and high composite fat (aHR = 3.26, 95% CI = 1.69-6.29; aHR = 2.19, 95% CI = 1.11-4.3) were associated with lower OS and DFS. Positive lymph nodes ≥3, progesterone receptor negative, and total radiation dose >5000 cGy significantly decreased both OS and DFS. A history of previous treatment before body composition assessment and surgery had a protective effect on OS and DFS. No association of sarcopenia, body mass index, and adiposity areas with survival outcomes was observed.

CONCLUSION

Low visceral-to-subcutaneous ratio and high composite fat were independent prognostic factors for OS and DFS in patients with LABC. However, other body composition parameters showed no effect on survival.

Active use of local exercise facilities can improve physical performance of community-dwelling older adults

[Purpose] In this study, we investigated the effects of local exercise facility use on physical function of Japanese community-dwelling older adults. [Participants and Methods] We analyzed data obtained from a cohort project initiated in 1991. The study included approximately 4,800 individuals from suburban areas of central Japan; we investigated 322 older individuals residing in Municipality A, who underwent physical fitness assessments in 2018 and 2019. We recorded participants' exercise facility use frequency and physical performance, based on handgrip strength, open-eye single-leg standing, timed up-and-go, and walking speed tests. [Results] Baseline values in the open-eye single-leg standing test were significantly higher in the no-use than in the low- and high-use groups. Follow-up assessments revealed that grip strength was significantly higher in the high-use than in the no- and low-use groups. [Conclusion] Active use of exercise facilities was positively correlated with maintenance and improvement in physical fitness among participants, which highlights the benefits of easily accessible exercise facilities in maintaining long-term physical function. Future studies should focus on functions that extend beyond physical fitness to develop effective support programs that address the evolving health needs of the aging population.

Safeguarding vitality and cognition: The role of sarcopenia in intrinsic capacity decline among octogenarians from multiple cohorts

BACKGROUND

Sarcopenia and intrinsic capacity (IC) declines pose significant challenges to healthy aging, particularly in the rapidly growing octogenarian population. This study aimed to elucidate the relationship between sarcopenia and declines in IC across multiple cohorts of community-dwelling older adults.

METHODS

Data from four Taiwanese cohorts were analyzed. Sarcopenia was diagnosed based on the Asian Working Group for Sarcopenia (AWGS) 2019 criteria (algorithm 1: categorized as either having possible sarcopenia or not (robust); algorithm 2: categorized as robust, possible sarcopenia or sarcopenia). IC was operationalized using the World Health Organization's Integrated Care for Older People (ICOPE) framework (step 1 and step 2), encompassing six domains: locomotion, vitality, vision, hearing, cognition, and psychological well-being. Multivariable logistic regression models were adopted to assess the association between sarcopenia and IC decline.

RESULTS

Among 599 octogenarians (median age 82.2 years, 54.8% male), the prevalence of possible sarcopenia (algorithm 1) was 64.6%. When adopting algorithm 2, the prevalence of possible sarcopenia and sarcopenia was 46,2% and 32.1%, respectively. After adjusting for covariates, participants with possible sarcopenia or sarcopenia (algorithm 2) were more likely to exhibit declines in vitality (ICOPE Step 1: possible sarcopenia aOR 3.65, sarcopenia aOR 4.74; ICOPE Step 2: possible sarcopenia aOR 5.11, sarcopenia aOR 14.77) and cognition (ICOPE Step 1: possible sarcopenia aOR 2.40, sarcopenia aOR 2.12; ICOPE Step 2: possible sarcopenia aOR 2.02, sarcopenia aOR 2.51) compared to robust individuals.

CONCLUSIONS

This study underscores the robust association between sarcopenia and declines in vitality and cognition among octogenarians, highlighting the importance of sarcopenia screening and management in promoting healthy longevity in this vulnerable population.

Sarcopenia Identification Using Alternative Vertebral Landmarks in Individuals with Lung Cancer

Background

(1)Sarcopenia, or low skeletal mass index (SMI), contributes to higher lung cancer mortality. The SMI at third lumbar vertebrae (L3) is the reference standard for body composition analysis. However, there is a need to explore the validity of alternative landmarks in this population. We compared the agreement of sarcopenia identification at the first lumbar (L1) and second lumbar (L2) to L3 in non-Hispanic Black (NHB) and White (NHW) individuals with lung cancer.

Methods

(2)This retrospective, cross-sectional study included 214 NHB and NHW adults with lung cancer. CT scans were analyzed to calculate the SMI at L1, L2, and L3. T-tests, chi-square, Pearson's correlation, Cohen's kappa, sensitivity, and specificity analysis were used.

Results

(3)Subjects presented with a mean age of 68.4 ± 9.9 years and BMI of 26.3 ± 6.0 kg/m2. Sarcopenia prevalence varied from 19.6% at L1 to 39.7% at L3. Cohen's kappa coefficient was 0.46 for L1 and 0.64 for L2, indicating weak and moderate agreement for the identification of sarcopenia compared to L3.

Conclusions

(4)Sarcopenia prevalence varied greatly depending on the vertebral landmark used for assessment. Using L2 or L1 alone resulted in a 16.8% and 23.8% misclassification of sarcopenia in this cohort of individuals with lung cancer.

Muscle strength in ostensibly healthy non-diabetic subjects

BACKGROUND/PURPOSE

Sarcopenia and decreased muscle strength (dynapenia) are emerging health issues. However, the study exploring muscle strength changes of both upper and lower limbs at the same time among all age groups is rare. This study aims to investigate the muscle strength and to establish a muscle strength norm of an ostensibly healthy non-diabetic Asian population.

METHODS

From 2018 June to 2020 March, subjects (aged from 20 to <80 years old) undergoing health checkup in Good Liver Medical Examination Center and National Taiwan University Hospital Geriatrics and Gerontology Department were enrolled. A battery of muscle power examinations including handgrip strength (HGS), five times sit-to-stand test (5TSTS), and one-leg standing test (OLST) were performed.

RESULTS

A total of 183 participants was enrolled, consisting of 92 females and 91 males. The finding shows the strongest HGS, best 5TSTS, and the longest OLST of both genders appeared in the 20-29-year-old group. Age, gender, and palm length are significantly related to HGS, whereas age is the only factor affecting 5TSTS and OLST. It revealed a progressive decline during ageing process, especially after age 60. Finally, Z-score and T-score norms of these were established.

CONCLUSION

These data will be useful as normal controls for muscle strength of specific disease groups. The application of the cutoffs from these data and their comparisons with the recommended cutoffs from various guidelines worth further exploration.

Correlation study between bone metabolic markers, bone mineral density, and sarcopenia

OBJECTIVE

To investigate the correlation between bone metabolism markers, bone mineral density (BMD), and sarcopenia.

METHODS

A total of 331 consecutive patients aged ≥ 60 years who were hospitalized between November 2020 and December 2021 were enrolled. Participants were divided into sarcopenia and non-sarcopenia groups according to the Asian Working Group on Sarcopenia criteria (AWGS, 2019). The clinical data, bone metabolism markers (β-CTX, N-MID, and TP1NP), and BMD were compared between the two groups.

RESULTS

Age, β-CTX, and N-MID of the sarcopenia group were higher than those of the non-sarcopenia group (P < 0.05), but the BMD T values were lower than those of the non-sarcopenia group (P < 0.05). Binary logistic regression analysis showed that increased femoral neck BMD (FNBMD) was a protective factor for sarcopenia, while increased β-CTX was a risk factor. Pearson/Spearman correlation analysis showed that the diagnostic indices of sarcopenia were positively correlated with FNBMD and negatively correlated with β-CTX and N-MID. Multiple linear regression analysis revealed that BMI and FNBMD significantly positively affected muscle strength and appendicular skeletal muscle mass (ASM). The FNBMD significantly positively affected physical performance, while β-CTX significantly negatively affected muscle strength, ASM, and physical performance.

CONCLUSION

Increased FNBMD may be a protective factor against sarcopenia, and increased β-CTX may be a risk factor. The FNBMD significantly positively affected the diagnostic indices of sarcopenia, while β-CTX significantly negatively affected them. BMD and bone metabolism marker levels may be considered in early screening for sarcopenia.

Deciphering the environmental chemical basis of muscle quality decline by interpretable machine learning models

BACKGROUND

Sarcopenia is known as a decline in skeletal muscle quality and function that is associated with age. Sarcopenia is linked to diverse health problems, including endocrine-related diseases. Environmental chemicals (ECs), a broad class of chemicals released from industry, may influence muscle quality decline.

OBJECTIVES

In this work, we aimed to simultaneously elucidate the associations between muscle quality decline and diverse EC exposures based on the data from the 2011-2012 and 2013-2014 survey cycles in the National Health and Nutrition Examination Survey (NHANES) project using machine learning models.

METHODS

Six machine learning models were trained based on the EC and non-EC exposures from NHANES to distinguish low from normal muscle quality index status. Different machine learning metrics were evaluated for these models. The Shapley additive explanations (SHAP) approach was used to provide explainability for machine learning models.

RESULTS

Random forest (RF) performed best on the independent testing data set. Based on the testing data set, ECs can independently predict the binary muscle quality status with good performance by RF (area under the receiver operating characteristic curve = 0.793; area under the precision-recall curve = 0.808). The SHAP ranked the importance of ECs for the RF model. As a result, several metals and chemicals in urine, including 3-phenoxybenzoic acid and cobalt, were more associated with the muscle quality decline.

CONCLUSIONS

Altogether, our analyses suggest that ECs can independently predict muscle quality decline with a good performance by RF, and the SHAP-identified ECs can be closely related to muscle quality decline and sarcopenia. Our analyses may provide valuable insights into ECs that may be the important basis of sarcopenia and endocrine-related diseases in United States populations.

Association of Dietary Vegetable and Fruit Consumption with Sarcopenia: A Systematic Review and Meta-Analysis

Previous studies have shown contradictory results regarding the association between vegetable and fruit consumption and the risk of sarcopenia. We aimed to evaluate this association using a meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched PubMed, EMBASE, and the Cochrane Library through July 2023 using related keywords. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated based on the random-effects model. We included 14 observational studies with 11 cross-sectional and three cohort studies involving 6436 sarcopenias among 33,801 participants. Vegetable and fruit consumption were significantly associated with reduced sarcopenia risk (OR, 0.61; 95% CI, 0.48 to 0.79; I2 = 59.8%). The association was significant in cross-sectional studies (OR, 0.64; 95% CI, 0.49 to 0.84; I2 = 56.3%; n = 11) but not in cohort studies (OR, 0.50; 95% CI, 0.22 to 1.11; I2 = 76.4%; n = 3). Moreover, the association was significant in age ≥60 (OR, 0.64; 95% CI, 0.49 to 0.83; I2 = 58.0%; n = 10). This meta-analysis suggests that eating vegetables and fruit reduces sarcopenia risk. However, as cohort studies provide a higher level of evidence than case-control studies, further prospective cohort studies should be conducted.

Development and validation of a prediction model for frailty in breast cancer patients with extended survival

BACKGROUND

Breast cancer (BC) patients with extended survival show a higher incidence of frailty. This study aimed to develop and validate a novel model combining sociodemographic factors (SF) and disease-related factors (DRF) to identify frailty in BC patients with extended survival.

METHODS

This cross-sectional study examined data from 1167 patients admitted to a large urban academic medical centre. Three types of predictive models were constructed in the training set (817 patients): the SF model, the DRF model, and the SF + DRF model (combined model). The model performance and effectiveness were assessed using receiver operating characteristic (ROC) curves, calibration plots and decision curves analysis (DCA). Then the model was subsequently validated on the validation set.

RESULTS

The incidence of frailty in BC patients with extended survival was 35.8%. We identified six independent risk factors including age, health status, chemotherapy, endocrine therapy, number of comorbidities and oral medications. Ultimately, we constructed an optimal model (combined model C) for frailty. The predictive model showed significantly high discriminative accuracy in the training set AUC: 0.754, (95% CI, 0.719-0.789; sensitivity: 76.8%, specificity: 62.2%) and validation set AUC: 0.805, (95% CI, 0.76-0.85), sensitivity: 60.8%, specificity: 87.1%) respectively. A prediction nomogram was constructed for the training and validation sets. Calibration and DCA were performed, which indicated that the clinical model presented satisfactory calibration and clinical utility. Ultimately, we implemented the prediction model into a mobile-friendly web application that provides an accurate and individualized prediction for BC.

CONCLUSIONS

The present study demonstrated that the prevalence of frailty in BC patients with extended survival was 35.8%. We developed a novel model for screening frailty, which may provide evidence for frailty screening and prevention.

Influences of muscle mass loss and exercise habits and personality traits on lower limb motor function among university students

Secondary sarcopenia, a risk factor even for young people, has attracted attention because of the deterioration of physical activity and nutritional status due to lifestyle change among university students. However, studies on the factors affecting motor function and their involvement are lacking. This cross-sectional study aimed to examine the influences of muscle mass loss and exercise and sleep habits on lower limb motor function, as well as the involvement of personality traits, in 101 university students. Approximately 6% of the participants had low skeletal muscle mass index, similar to previous reports, and that only exercise habits in high school were responsible for muscle mass loss (direct effect =  - 0.493; p < 0.05), wherease low skeletal muscle mass (direct effect =  - 0.539; p < 0.01) and current exercise habits (direct effect = 0.410; p < 0.01) were responsible for lower limb motor function. Additionaly, only the personality trait of high intellectual curiosity was involved in the establishment of exercise habits in high school, but no other personality traits showed a significant effect. In the prevention of secondary sarcopenia, encouraging sustained exercise habits while considering the influence of different personality traits is expected to prevent the decline in muscle mass and motor function.

Self-Reported Sleep Duration Is a Useful Tool to Predict Sarcopenia in Chilean Older Adults: Evidence from the ALEXANDROS Longitudinal Study

Age-related sleep disorders share common pathways with sarcopenia. Prospective data from Latin American populations are scarce, and the association between sleep disorders and sarcopenia in Chileans remains unknown. Thus, we aimed to study the longitudinal association between sleep disorders and sarcopenia in a cohort study of 1116 community-dwelling Chilean older people ≥60 years old from the ALEXANDROS cohorts. After the exclusion criteria, 318 subjects were followed. Sociodemographic data, self-reported chronic diseases, sedentarism, sleep characteristics, anthropometric measurements, handgrip strength, and muscle performance were assessed. Results indicated that at baseline, the prevalence of sarcopenia was 24.10% without gender differences, and the prevalence of self-reported sleep problems was 23.3%, higher in women (26.46% versus 17.15% in men). The adjusted Cox regression models for sarcopenia showed an association between sarcopenia, sleep disorders (HR = 2.08, 95% IC 1.14-3.80), and long sleep duration (HR = 2.42, 95% IC 1.20-4.91). After 8.24 years of follow-up, there were 2.2 cases of sarcopenia per 100 person-years. This study demonstrates that sleep disorders are an independent risk factor for sarcopenia in Chilean older people. The identification of sleep disorders through self-reported data provides an opportunity for early identification of risk and cost-effective sarcopenia prevention.

Association between the systemic immune-inflammation index and sarcopenia: a systematic review and meta-analysis

BACKGROUND

Sarcopenia is associated with increased morbidity and mortality. The systemic immune-inflammation index (SII) has been correlated to a variety of disorders. The present study conducted a systematic review and meta-analysis to investigate the relationship between SII and sarcopenia.

METHODS

A literature search was performed in Web of Science, PubMed, Embase, Cochrane Library, CINAHL, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Wanfang Database, and VIP Chinese Science and Technology Database, from inception to March 2024. Then, the literature quality was assessed. After the heterogeneity test, a random effects or fixed effects model was applied to establish the forest plot, and investigate the relationship between SII and sarcopenia. Then, the sensitivity analysis and publication bias were examined.

RESULTS

Nine articles, which included 18,634 adults, were analyzed. Sarcopenic adults had higher SII levels, when compared to non-sarcopenic adults (standardized mean difference [SMD] = 0.66, 95% confidence interval [CI] = 0.22 - 0.19, p = 0.003). The high SII level was associated to the increased risk of sarcopenia (odds ratio = 1.52, 95% CI = 1.09-2.13, p = 0.01). In addition, the subgroup analysis revealed that the SII levels were higher in the sarcopenic group, when compared to the non-sarcopenic group, in elderly adults, as well as in adults with or without gastrointestinal disorders. The analysis was robust with a low risk of publication bias.

CONCLUSIONS

SII is closely associated to sarcopenia. Sarcopenic adults had elevated SII levels. The high SII level increased the risk of sarcopenia. Large scale multi-center prospective studies are required to validate these study findings.

Bibliometric analysis of research on sarcopenic obesity: a review of scientific literature

Considering the current prevalence in obesity and sarcopenia globally, this study aimed to summarize the development of sarcopenic obesity research to establish the topic's past, present, and future research direction using a bibliometric analysis. A comprehensive search for publications on sarcopenia and obesity was conducted in the Web of Science (WoS) database until the 31st of December 2023. We performed a detailed descriptive analysis, considering metrics like sources, authors, and documents, along with analyzing conceptual and social structures to map sarcopenic obesity research. Between 1993 and 2023, there were 4978 publications on sarcopenic obesity, representing 22.6% of the whole sarcopenia research (22070). Most published articles were originals (74.6%), and one of the highest increments in the fields was seen after 2010. The most significant contribution in this research area falls under the categories of Nutrition & Dietetics, Gerontology, and Geriatrics & Gerontology. Among regions, scientific production was located in 93 different countries. The United States, China, and South Korea had the highest contributions. The most relevant keywords were sarcopenia, obesity, and body composition. Research on sarcopenic obesity primarily focuses on epidemiology and identifying risk factors and outcome predictors. Yet, there is a shortage of research addressing prevention, early detection, and treatments to enhance the health of individuals with sarcopenia.

Synergistic Effects of Nutrients on Musculoskeletal Health in Gerontology: Understanding the Combined Impact of Macronutrients and Micronutrients

With the global aging population, addressing prevalent age-related conditions such as osteoporosis and sarcopenia is crucial. Traditional nutritional strategies focusing on single nutrients like calcium, vitamin D, or protein have limitations, prompting a nuanced exploration of the relationship between aging, nutrition, and musculoskeletal health. This cross-sectional study examines the complex interplay between dietary intake of macronutrients, common micronutrients, and water, as well as their association with musculoskeletal health in adults aged 50 to 80 years, using U.S. National Health and Nutrition Examination Survey data (NHANES). Employing multiple linear regression, restricted cubic splines, weighted quantile sum (WQS), and quantile-based g-computation (QGC) regression models, our initial analysis using the WQS model revealed that a one-quartile increase in mixed macronutrient intake was associated with a significant 0.009 unit increase in bone mineral density (BMD) and a 0.670 unit increase in grip strength, while a similar increase in mixed micronutrient intake showed a 0.007 unit increase in BMD and a 0.442 unit increase in grip strength. Our findings highlight the importance of a balanced dietary approach in promoting musculoskeletal health in the elderly, offering holistic strategies for overall well-being.

The impact of sarcopenia in the treatment for patients with head and neck cancer

Sarcopenia is a disease in which a decline in muscle mass with age is associated with a decline in physical performance. In the field of otorhinolaryngology, head and neck surgery, sarcopenia is gaining attention as a cause of swallowing disorders and as a problem in the treatment of head and neck cancer. Head and neck cancer occurs in anatomical sites related to swallowing, so patients with head and neck cancer are prone to swallowing disorders and "nutrition-related sarcopenia." Since it is a cancer, it also becomes a "disease-related sarcopenia," making it easy for patients to develop secondary sarcopenia. Medical intervention against sarcopenia is important in order to decrease the number of adverse events related to treatments for cases with sarcopenia, with reports stating that proactive exercise and nutritional therapy prior to treatment for cases with sarcopenia contributes to a decrease in serious complications as well as improving the survival rate. It is the same for head and neck cancer patients with sarcopenia, so intervention prior to treatment of head and neck cancer is an area that is expected to see reports in the future. However, if the disease is malignant, it is highly likely that sarcopenia cannot be sufficiently improved due to the short period of time from diagnosis to the beginning of treatment. In this case, choosing a treatment that takes sarcopenia into consideration is another way to handle it. Assessing sarcopenia prior to treatment may help avoid post-treatment pneumonia related to sarcopenia, postoperative complications including fistula, radiation-induced toxicity including swallowing disorders, and chemotherapy-related toxicity, and it is believed to greatly contribute to the prognosis of the overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS).

Examining the mediating role of muscle quantity in adolescents: associations with adiposity, cardiorespiratory fitness, muscular fitness, and cardiometabolic risk factors

The aim of this study was to evaluate the mediation role of muscle quantity in the relationship between physical fitness and cardiometabolic risk factors (CMRF) in adolescents. This cross-sectional study conducted with 120 adolescents of both sexes, aged between 10 and 17 years. Body mass, height, fat mass (FM), lean mass, blood pressure, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin, cardiorespiratory fitness (CRF) and 1 repetition maximum strength (1-RM) with evaluation of the leg press 45° (RM-leg), bench press (RM-bench) and arm curl (RM-arm). Body mass index z-score, appendicular skeletal muscle mass, appendicular skeletal muscle mass index, lean mass index (LMI), muscle-to-fat ratio (MFR), age at peak height velocity, and CMRF z-score were calculated. The direct relation between FM and CMRF was mediated by the LMI (26%) and inverse relation between CRF and CMRF was mediated by the LMI (26%). For girls, the direct relation between FM and CMRF was mediated by the LMI (32%); the inverse relation between CRF, RM-leg, RM-arm and CMRF was mediated by the LMI (32%, 33%, and 32%, respective). For boys, the indirect effect was not significant, indicating that LMI is not a mediator in the relation between FM, CRF, 1-RM with CMRF. The direct relation between RM-leg and CMRF was mediated by the MRF (16%). This finding evidenced the importance of promoting a healthy lifestyle to improve physical fitness levels and the quantity of muscle mass in adolescents.

Low grip strength and gait speed as markers of dependence regarding basic activities of daily living: the FIBRA study

OBJECTIVE

Marincolo et al. showed that older adults without limitations in basic activities of daily living at baseline presented with an 11.7% concomitant presence of functional dependence, slow gait speed, and low muscle strength at follow-up. Slow gait speed remains a predictor of dependence in basic activities of daily living. To determine whether low muscle strength and low gait speed increase the risk of disability related to basic activities of daily living in community-dwelling older adults.

METHODS

A longitudinal study (9 years of follow-up) was conducted with 390 older adults who were independent in basic activities of daily living at baseline and answered the Katz Index at follow-up. Associations were determined using Pearson's χ2 test with a 5% significance level and logistic regression analysis.

RESULTS

Increases in prevalence between baseline and follow-up were observed for low muscle strength (17.5%-38.2%), slow gait speed (26.0%-81.1%), and functional dependence (10.8%-26.6%). At follow-up, 11.7% of the participants had concomitant functional dependence, slow gait speed, and low muscle strength. Slow gait speed remained a predictor of dependence in basic activities of daily living (odds ratio=1.90; 95% confidence interval=1.06-3.41).

CONCLUSION

Slow gait speed is a predictor of functional dependence, constituting an important variable for screening functional decline.

Cross-Cultural Adaptation and Validation of the Portuguese Version of the SARC-F in Community-Dwelling Older Adults

(1) Background: The goal of this study was to analyze the reliability and validity of the Portuguese version of the SARC-F in older adults. (2) Methods: A total of 100 participants (77.1 ± 7.36 years, 73% women) were included in the study. In a first phase, the Portuguese SARC-F was adapted following the standardized forward-backward translation procedure, and internal consistency as well as inter-rater and test-retest reliability of the Portuguese SARC-F were analyzed. Secondly, clinical validation was evaluated by comparing the SARC-F total score with five operational definitions of sarcopenia and with other sarcopenia-related measurements. Discriminant validity, with respect to low muscle mass and strength and physical function were analyzed. (3) Results: The Portuguese SAR-F showed acceptable internal consistency (Cronbach α = 0.82), excellent inter-rater reliability (total score), and substantial to excellent test-retest reliability (ICC = 0.891 for the total score). Specificity ranged from 72.5% (FNIH) to 73.4 (IGWS), and negative predictive values went from 91.8% (EWGSOP1) to 97.3% (FNIH), but low sensitivity and positive predictive value were observed. The Portuguese SARC-F showed a moderate ability to discriminate people with low muscle strength (AUC = 0.78) and gait speed (AUC = 0.89). (4) Conclusions: The Portuguese SARC-F is a valid and reliable tool for ruling out sarcopenia in community-dwelling older adults and can discriminate between people with low handgrip strength and gait speed.

High serum klotho levels are inversely associated with the risk of low muscle mass in middle-aged adults: results from a cross-sectional study

Objective

Muscle mass gradually declines with advancing age, and as an anti-aging protein, klotho may be associated with muscle mass. This study aims to explore the relationship between klotho levels and muscle mass in the middle-aged population.

Methods

Utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning 2011 to 2018, we conducted a cross-sectional analysis on a cohort of individuals aged 40-59. Weighted multivariable analysis was employed to assess the correlation between klotho and low muscle mass, with stratified and Restricted Cubic Spline (RCS) analyses.

Results

The cross-sectional investigation revealed a significant negative correlation between klotho levels and the risk of low muscle mass (Model 3: OR = 0.807, 95% CI: 0.712-0.915). A notable interaction between klotho and sex was observed, with a significant interaction effect (P for interaction = 0.01). The risk association was notably higher in females. The risk association was notably higher in females. Additionally, RCS analysis unveiled a significant linear relationship between klotho and low muscle mass (P for nonlinear = 0.9495, P for overall<0.0001).

Conclusion

Our observational analysis revealed a noteworthy inverse relationship between klotho and low muscle mass, particularly prominent among female participants. This discovery provides crucial insights for the development of more effective intervention strategies and offers a new direction for enhancing muscle quality in the middle-aged population.

Type 2 diabetes mellitus related sarcopenia: a type of muscle loss distinct from sarcopenia and disuse muscle atrophy

Muscle loss is a significant health concern, particularly with the increasing trend of population aging, and sarcopenia has emerged as a common pathological process of muscle loss in the elderly. Currently, there has been significant progress in the research on sarcopenia, including in-depth analysis of the mechanisms underlying sarcopenia caused by aging and the development of corresponding diagnostic criteria, forming a relatively complete system. However, as research on sarcopenia progresses, the concept of secondary sarcopenia has also been proposed. Due to the incomplete understanding of muscle loss caused by chronic diseases, there are various limitations in epidemiological, basic, and clinical research. As a result, a comprehensive concept and diagnostic system have not yet been established, which greatly hinders the prevention and treatment of the disease. This review focuses on Type 2 Diabetes Mellitus (T2DM)-related sarcopenia, comparing its similarities and differences with sarcopenia and disuse muscle atrophy. The review show significant differences between the three muscle-related issues in terms of pathological changes, epidemiology and clinical manifestations, etiology, and preventive and therapeutic strategies. Unlike sarcopenia, T2DM-related sarcopenia is characterized by a reduction in type I fibers, and it differs from disuse muscle atrophy as well. The mechanism involving insulin resistance, inflammatory status, and oxidative stress remains unclear. Therefore, future research should further explore the etiology, disease progression, and prognosis of T2DM-related sarcopenia, and develop targeted diagnostic criteria and effective preventive and therapeutic strategies to better address the muscle-related issues faced by T2DM patients and improve their quality of life and overall health.

Psoas muscle area as a predictor of low muscle mass in Asian patients with compensated advanced chronic liver disease

PURPOSE

The relationship between the psoas muscle index (PMI) and the appendicular skeletal muscle index (ASMI) in patients with compensated advanced chronic liver disease (cACLD) is not yet understood. Our goal is to determine which level of the lumbar spine best represents the appendicular skeletal muscle.

METHODS AND MATERIALS

This retrospective study involved patients with cACLD between January 2020 and December 2021. We documented the patients' body weight, height, gait speed, handgrip strength, appendicular skeletal muscle measured by DXA, and psoas muscle area segmented on computed tomography or magnetic resonance imaging. Low muscle mass, as defined by the Asian working group for sarcopenia, is less than 7.0 kg/m2 in males and less than 5.4 kg/m2 in females. We analyzed the correlation between PMI and ASMI.

RESULTS

A total of 134 patients were enrolled in the study, with 74 being male and 60 being female. The mean age was 63.9 ± 7.7 years old. Significant associations (p < 0.001) were found between PMI of all levels and ASMI. In the analysis of Pearson's correlation coefficients, it was noted that the r value increased gradually in both males (r = 0.3197 at L2, 0.4006 at L3, 0.5769 at L4) and females (r = 0.3771 at L2, 0.4557 at L3, 0.5251 at L4). Similarly, the area under the curve (AUC) values predicting low muscle mass were as follows: for males, AUC=0.582 at L2, 0.619 at L3, 0.728 at L4; for females, AUC=0.685 at L2, 0.733 at L3, 0.744 at L4. The cut-off point for PMI in males was 4.12 at L2, 6.25 at L3, and 8.48 at L4, while in females was 2.61 at L2, 4.47 at L3, 6.07 at L4.

CONCLUSION

The Psoas muscle index can be used to assess the muscle mass status in patients with cACLD. Among the various levels that can be used, we recommend using the fourth inferior endplate of the lumbar spine, as it shows the highest correlation. Additionally, we suggest using a PMI cut-off point of 8.48 cm2/m2 for males and 6.07 cm2/m2 for females as a predictor of low muscle mass in Asian.

Role of Myostatin in Rheumatoid Arthritis: A Review of the Clinical Impact

Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects synovial joints and that frequently involves extra-articular organs. A multiplicity of interleukins (IL) participates in the pathogenesis of RA, including IL-6, IL-1β, transforming growth factor-beta (TGF-β), and tumor necrosis factor (TNF)-α; immune cells such as monocytes, T and B lymphocytes, and macrophages; and auto-antibodies, mainly rheumatoid factor and anti-citrullinated protein antibodies (ACPAs). Skeletal muscle is also involved in RA, with many patients developing muscle wasting and sarcopenia. Several mechanisms are involved in the myopenia observed in RA, and one of them includes the effects of some interleukins and myokines on myocytes. Myostatin is a myokine member of the TGF-β superfamily; the overproduction of myostatin acts as a negative regulator of growth and differentiates the muscle fibers, limiting their number and size. Recent studies have identified abnormalities in the serum myostatin levels of RA patients, and these have been found to be associated with muscle wasting and other manifestations of severe RA. This review analyzes recent information regarding the relationship between myostatin levels and clinical manifestations of RA and the relevance of myostatin as a therapeutic target for future research.

Association of dietary inflammatory indices with sarcopenia and all-cause mortality in COPD patients

Background

Sarcopenia frequently occurs as a comorbidity in individuals with COPD. However, research on the impact of Appendicular Skeletal Muscle Mass (ASM) on survival in COPD patients is scarce. Moreover, there is a lack of research on the association between dietary pro-inflammatory capacity and sarcopenia in COPD.

Methods

We analyzed data from the National Health and Nutrition Examination Survey (NHANES) covering the years 1999 to 2006 and 2011 to 2018. We aimed to investigate the relationship between the Dietary Inflammatory Index (DII) and sarcopenia prevalence among adults diagnosed with COPD in the United States. Furthermore, we sought to explore the relationship between sarcopenia, ASMI, and all-cause mortality. The study included a total of 1,429 eligible adult participants, divided into four groups based on quartiles of DII, with adjustments for sample weights. Methodologically, we used multivariable logistic regression analyses and to examine the association between DII and sarcopenia. Additionally, we used restricted cubic spline (RCS) tests to evaluate potential non-linear relationships. To assess the effect of sarcopenia on overall all-cause mortality, we used Kaplan-Meier models and Cox proportional hazards models. Moreover, we used RCS analyses to investigate potential non-linear relationships between ASMI and all-cause mortality. Subgroup analyses were conducted to confirm the reliability of our study findings.

Results

In our COPD participant cohort, individuals with higher DII scores were more likely to be female, unmarried, have lower educational attainment, and show lower ASMI. Using multivariable logistic regression models, we found a positive association between the highest quartile of DII levels and sarcopenia incidence [Odds Ratio (OR) 2.37; 95% Confidence Interval (CI) 1.26-4.48; p = 0.01]. However, analysis of RCS curves did not show a non-linear relationship between DII and sarcopenia. Throughout the entire follow-up period, a total of 367 deaths occurred among all COPD patients. Kaplan-Meier survival curves showed a significantly higher all-cause mortality rate among individuals with concurrent sarcopenia (p < 0.0001). Cox proportional hazards model analysis showed a 44% higher risk of all-cause mortality among COPD patients with sarcopenia compared to those without sarcopenia [Hazard Ratio (HR): 1.44; 95% CI 1.05-1.99; p < 0.05]. Additionally, our final RCS analyses revealed a significant non-linear association between ASMI levels and all-cause mortality among COPD patients, with a turning point identified at 8.32 kg/m2. Participants with ASMI levels above this inflection point had a 42% lower risk of all-cause mortality compared to those with ASMI levels below it (HR 0.58; 95% CI 0.48-0.7).

Conclusion

We observed a significant association between concurrent sarcopenia and an increased risk of all-cause mortality in COPD patients within the United States. Moreover, ASMI demonstrated a non-linear association with all-cause mortality, with a critical threshold identified at 8.32 kg/m2. Our findings also revealed an association between DII and the presence of sarcopenia. Consequently, further investigations are warranted to explore the feasibility of dietary DII adjustments as a means to mitigate muscle wasting and enhance the prognosis of COPD.

Urea to creatinine ratio as a predictor of persistent critical illness

INTRODUCTION

Persistent critical illness (PCI) is a syndrome in which the acute presenting problem has been stabilized, but the patient's clinical state does not allow ICU discharge. The burden associated with PCI is substantial. The most obvious marker of PCI is prolonged ICU length of stay (LOS), usually greater than 10 days. Urea to Creatinine ratio (UCr) has been suggested as an early marker of PCI development.

METHODS

A single-center retrospective study. Data of patients admitted to a general mixed medical-surgical ICU during Jan 1st 2018 till Dec 31st 2022 was extracted, including demographic data, baseline characteristics, daily urea and creatinine results, renal replacement therapy (RRT) provided, and outcome measures - length of stay, and mortality (ICU, and 90 days). Patients were defined as PCI patients if their LOS was >10 days. We used Fisher exact test or Chi-square to compare PCI and non-PCI patients. The association between UCr with PCI development was assessed by repeated measures linear model. Multivariate Cox regression was used for 1 year mortality assessment.

RESULTS

2098 patients were included in the analysis. Patients who suffered from PCI were older, with higher admission prognostic scores. Their 90-day mortality was significantly higher than non-PCI patients (34.58% vs 12.18%, p < 0.0001). A significant difference in UCr was found only on the first admission day among all patients. This was not found when examining separately surgical, trauma, or transplantation patients. We did not find a difference in UCr in different KDIGO (Kidney Disease Improving Global Outcomes) stages. Elevated UCr and PCI were found to be significantly associated with 1 year mortality.

CONCLUSION

In this single center retrospective cohort study, UCr was not found to be associated with PCI development.

Weightbearing versus non-weight bearing in geriatric distal femoral fractures: a systematic review and meta-analysis

BACKGROUND

Demographics of patients who sustain geriatric distal femoral fractures (DFF) match those of patients with neck-of-femur fractures but have limited evidence with which to support post-operative weightbearing protocols.

PURPOSE

This systematic review sought to identify any difference in outcomes for elderly patients with DFF who were allowed early versus delayed weightbearing postoperatively.

METHODS

DATA SOURCES: PubMed, Medline, Embase and The Cochrane Library, reference lists of retrieved articles.

STUDY SELECTION

English language papers published between January 2010 and February 2023 with AO-OTA type 33A, B and C femoral fractures as well as Lewis and Rorabeck Type I and II periprosthetic DFF surgically treated with either a lateral locking plate or retrograde intramedullary nail and an average patient age of ≥ 60 years.

DATA EXTRACTION

Studies were assessed for inclusion by two authors and quality was assessed using the MINORS tool.

DATA SYNTHESIS

Sixteen studies were included, Meta-analysis of non-union, malunion, infection, delayed union and implant complications was performed using Microsoft Excel and the MetaXL extension. The data on return to mobility were presented in narrative form. The analyses demonstrated no difference between the early and delayed weightbearing groups.

CONCLUSIONS

There are no significant differences in complication rates between early versus delayed weightbearing after surgery for DFF in an elderly population. The study results are limited by high heterogeneity and low-quality studies. High quality, prospective studies are needed to determine the ideal postoperative weightbearing protocol.

LEVEL OF EVIDENCE

Level III, Systematic Review and Meta-analysis of Level III studies. International Prospective Register of Systematic Reviews registration-Prospero CRD42022371460.

Development and validation of a reliable method for automated measurements of psoas muscle volume in CT scans using deep learning-based segmentation: a cross-sectional study

OBJECTIVES

We aimed to develop an automated method for measuring the volume of the psoas muscle using CT to aid sarcopenia research efficiently.

METHODS

We used a data set comprising the CT scans of 520 participants who underwent health check-ups at a health promotion centre. We developed a psoas muscle segmentation model using deep learning in a three-step process based on the nnU-Net method. The automated segmentation method was evaluated for accuracy, reliability, and time required for the measurement.

RESULTS

The Dice similarity coefficient was used to compare the manual segmentation with automated segmentation; an average Dice score of 0.927 ± 0.019 was obtained, with no critical outliers. Our automated segmentation system had an average measurement time of 2 min 20 s ± 20 s, which was 48 times shorter than that of the manual measurement method (111 min 6 s ± 25 min 25 s).

CONCLUSION

We have successfully developed an automated segmentation method to measure the psoas muscle volume that ensures consistent and unbiased estimates across a wide range of CT images.

Age Is Just a Number for Older Kidney Transplant Patients

The rise in the mean age of the global population has led to an increase in older kidney transplant (KT) patients. This demographic shift, coupled with the ongoing organ shortage, requires a nuanced understanding of which older adults are most suitable for KT. Recognizing the increased heterogeneity among older adults and the limitations of solely relying on chronological age, there is a need to explore alternative aging metrics beyond chronological age. In this review, we discuss the impact of older age on access to KT and postoperative outcomes. Emphasizing the need for a comprehensive evaluation that extends beyond chronological age, we explore alternative aging metrics such as frailty, sarcopenia, and cognitive function, underscoring their potential role in enhancing the KT evaluation process. Most importantly, we aim to contribute to the ongoing discourse, fostering an optimized approach to KT for the rapidly growing population of older adults.

Myosteatosis is closely associated with sarcopenia and significantly worse outcomes in patients with cirrhosis

BACKGROUND & AIMS

Sarcopenia and myosteatosis are common in patients with cirrhosis. This study aimed to determine the prevalence of these muscle changes, their interrelations and their prognostic impact over a 12-month period.

METHODS

We conducted a prospective multicentre study involving 433 patients. Sarcopenia and myosteatosis were evaluated using computed tomography scans. The 1-year cumulative incidence of relevant events was assessed by competing risk analysis. We used a Fine-Gray model adjusted for known prognostic factors to evaluate the impact of sarcopenia and myosteatosis on mortality, hospitalization, and liver decompensation.

RESULTS

At enrolment, 166 patients presented with isolated myosteatosis, 36 with isolated sarcopenia, 135 with combined sarcopenia and myosteatosis and 96 patients showed no muscle changes. The 1-year cumulative incidence of death in patients with either sarcopenia and myosteatosis (13.8%) or isolated myosteatosis (13.4%) was over twice that of patients without muscle changes (5.2%) or with isolated sarcopenia (5.6%). The adjusted sub-hazard ratio for death in patients with muscle changes was 1.36 (95% CI 0.99-1.86, p = 0.058). The cumulative incidence of hospitalization was significantly higher in patients with combined sarcopenia and myosteatosis than in patients without muscle changes (adjusted sub-hazard ratio 1.18, 95% CI 1.04-1.35). The cumulative incidence of liver decompensation was greater in patients with combined sarcopenia and myosteatosis (p = 0.018) and those with isolated sarcopenia (p = 0.046) than in patients without muscle changes. Lastly, we found a strong correlation of function tests and frailty scores with the presence of muscle changes.

CONCLUSIONS

Myosteatosis, whether alone or combined with sarcopenia, is highly prevalent in patients with cirrhosis and is associated with significantly worse outcomes. The prognostic role of sarcopenia should always be evaluated in relation to the presence of myosteatosis.

IMPACT AND IMPLICATIONS

This study investigates the prognostic role of muscle changes in patients with cirrhosis. The novelty of this study is its multicentre, prospective nature and the fact that it distinguishes between the impact of individual muscle changes and their combination on prognosis in cirrhosis. This study highlights the prognostic role of myosteatosis, especially when combined with sarcopenia. On the other hand, the relevance of sarcopenia could be mitigated when considered together with myosteatosis. The implication from these findings is that sarcopenia should never be evaluated individually and that myosteatosis may play a dominant role in the prognosis of patients with cirrhosis.

A genome-wide association study identifies a locus associated with knee extension strength in older Japanese individuals

Sarcopenia is a common skeletal muscle disease in older people. Lower limb muscle strength is a good predictive value for sarcopenia; however, little is known about its genetic components. Here, we conducted a genome-wide association study (GWAS) for knee extension strength in a total of 3452 Japanese aged 60 years or older from two independent cohorts. We identified a significant locus, rs10749438 which is an intronic variant in TACC2 (transforming acidic coiled-coil-containing 2) (P = 4.2 × 10-8). TACC2, encoding a cytoskeleton-related protein, is highly expressed in skeletal muscle, and is reported as a target of myotonic dystrophy 1-associated splicing alterations. These suggest that changes in TACC2 expression are associated with variations in muscle strength in older people. The association was consistently observed in young and middle-aged subjects. Our findings would shed light on genetic components of lower limb muscle strength and indicate TACC2 as a potential therapeutic target for sarcopenia.

Appendicular lean mass and the risk of stroke and Alzheimer's disease: a mendelian randomization study

BACKGROUND

Appendicular lean mass (ALM) is a good predictive biomarker for sarcopenia. And previous studies have reported the association between ALM and stroke or Alzheimer's disease (AD), however, the causal relationship is still unclear, The purpose of this study was to evaluate whether genetically predicted ALM is causally associated with the risk of stroke and AD by performing Mendelian randomization (MR) analyses.

METHODS

A two-sample MR study was designed. Genetic variants associated with the ALM were obtained from a large genome-wide association study (GWAS) and utilized as instrumental variables (IVs). Summary-level data for stroke and AD were generated from the corresponding GWASs. We used random-effect inverse-variance weighted (IVW) as the main method for estimating causal effects, complemented by several sensitivity analyses, including the weighted median, MR-Egger, and MR-pleiotropy residual sum and outlier (MR-PRESSO) methods. Multivariable analysis was further conducted to adjust for confounding factors, including body mass index (BMI), type 2 diabetes mellitus (T2DM), low density lipoprotein-C (LDL-C), and atrial fibrillation (AF).

RESULTS

The present MR study indicated significant inverse associations of genetically predicted ALM with any ischemic stroke ([AIS], odds ratio [OR], 0.93; 95% confidence interval [CI], 0.89-0.97; P = 0.002) and AD (OR, 090; 95% CI 0.85-0.96; P = 0.001). Regarding the subtypes of AIS, genetically predicted ALM was related to the risk of large artery stroke ([LAS], OR, 0.86; 95% CI 0.77-0.95; P = 0.005) and small vessel stroke ([SVS], OR, 0.80; 95% CI 0.73-0.89; P < 0.001). Regarding multivariable MR analysis, ALM retained the stable effect on AIS when adjusting for BMI, LDL-C, and AF, while a suggestive association was observed after adjusting for T2DM. And the estimated effect of ALM on LAS was significant after adjustment for BMI and AF, while a suggestive association was found after adjusting for T2DM and LDL-C. Besides, the estimated effects of ALM were still significant on SVS and AD after adjustment for BMI, T2DM, LDL-C, and AF.

CONCLUSIONS

The two-sample MR analysis indicated that genetically predicted ALM was negatively related to AIS and AD. And the subgroup analysis of AIS revealed a negative causal effect of genetically predicted ALM on LAS or SVS. Future studies are required to further investigate the underlying mechanisms.

The influence of mindfulness meditation combined with progressive muscle relaxation training on the clinical efficacy and quality of life of patients with sarcopenia receiving haemodialysis: a randomised controlled trial

OBJECTIVE

To study the effect of mindfulness meditation combined with progressive muscle relaxation training on the clinical efficacy and quality of life in patients with sarcopenia receiving maintenance haemodialysis (MHD).

METHODS

Eligible patients with sarcopenia in our hospital were randomly assigned to a control group (n = 24) and an intervention group (n = 25). The control group received conventional dialysis treatment, while the intervention group underwent mindfulness meditation combined with progressive muscle relaxation training during the interdialysis period in addition to conventional dialysis treatment. The effect of the intervention was evaluated after 12 weeks.

RESULTS

There were no significant differences in the baseline values of various parameters between the two groups. Exercise capacity (sit-to-stand test,handgrip,time to 10 sit-ups) significantly improved in the intervention group after 12 weeks (32.68 ± 8.32 vs 26.50 ± 6.83; 37.42 ± 10.12 vs 28.12 ± 8.51; 19.8 ± 5.40 vs 25.29 ± 7.18) (p < 0.05). In terms of the kidney disease quality of life (KDQOLTM) score, all other dimensions except sexual function, social functioning, burden of kidney disease and work status dimensions showed significant improvement compared to the baseline (p < 0.05). In the control group, only the dialysis staff encouragement (DSE) and patient satisfaction (PS) dimensions showed slight improvements compared to the baseline (p > 0.05). When compared with the control group, the intervention group showed significant improvements in 10 dimensions of exercise capacity and KDQOLTM scores for physical function, role-physical, general health, energy, symptom/problem list, sleep, DSE, pain, cognitive function, emotional well-being and patient PS after 12 weeks (61.30 ± 5.38 vs 42.98 ± 5.73; 57.50 ± 3.55 vs 50.70 ± 3.62) (p < 0.05). Some inflammatory markers, such as the levels of interleukin-6 and high-sensitivity C-reactive protein (30.29 ± 2.96 vs 17.65 ± 3.22; 8.93 ± 0.99 vs 3.02 ± 0.34), showed a decrease during the intervention, while albumin and prealbumin levels were significantly increased compared with the baseline (30.62 ± 1.65 vs 35.60 ± 1.68; 0.32 ± 0.05 vs 0.44 ± 0.07) (p < 0.05).

CONCLUSION

Combined intervention training can improve the motor ability and quality of life of patients with sarcopenia within a short period of time.

Associations of appendicular lean mass and abdominal adiposity with insulin resistance in older adults: A cross-sectional study

Loss of lean muscle mass and accumulation of adipose tissue are changes associated with aging. Previous studies have documented various components of body composition as predictors for insulin resistance. The objective of this study was to investigate whether components of body composition-appendicular lean mass (ALM) and/or abdominal fat mass (AFM)-correlate with insulin resistance in older men and women. This was a cross-sectional study of 92 older men and women. Weight was classified according to body mass index (BMI)-normal (BMI <25), overweight (BMI 25-30), and obese (BMI >30). All body composition data was determined by dual energy x-ray absorptiometry (DEXA), and insulin resistance was assessed by the homeostatic model assessment of insulin resistance (HOMA-IR). Multivariable regression models with two-way interaction terms were employed to assess whether the associations between components of body composition and log HOMA varied by BMI categories. Adjusted regression showed that log HOMA was significantly associated with AFM (estimate ± standard error: 0.055 ± 0.026) and ALM (0.057 ± 0.029) for the overweight participants (p-values <0.05). Additionally, the adjusted associations between log HOMA and ALM were significantly greater for participants who were either obese or overweight compared to those with a normal BMI (p<0.002). Less consistent relationships were observed between insulin resistance and abdominal fat mass across BMI categories, whereas more consistent associations were observed between insulin resistance and appendicular lean mass in individuals with greater BMI. Further research is needed to clarify if lipid deposition within muscle tissue promotes muscle dysfunction and thereby increases risk for insulin resistance.

An insight into the causal relationship between sarcopenia-related traits and venous thromboembolism: A mendelian randomization study

BACKGROUND

As a geriatric syndrome, sarcopenia has a high prevalence in the old population and represents an impaired state of health with adverse health outcomes. A strong clinical interest in its relationship with venous thromboembolism (VTE), which is a complex trait disease with a heterogeneous annual incidence rate in different countries, has emerged. The relationship between sarcopenia and venous thromboembolism has been reported in observational studies but the causality from sarcopenia to VTE remained unclarified. We aimed to assess the causal effect of sarcopenia on the risk of VTE with the two-sample Mendelian randomization (MR) method.

METHODS

Two sets of single-nucleotide polymorphisms (SNPs), derived from two published genome-wide association study (GWAS) meta-analyses and genetically indexing muscle weakness and lean muscle mass separately, were pooled into inverse variance weighted (IVW), weighted median and MR-Egger analyses.

RESULTS

No evidence was found for the causal effect of genetically predicted muscle weakness (IVW: OR = 0.90, 95% CI = 0.76-1.06, p = 0.217), whole body lean mass (IVW: OR = 1.01, 95% CI = 0.87-1.17, p = 0.881) and appendicular lean mass (IVW: OR = 1.13, 95% CI = 0.82-1.57, p = 0.445) on the risk of VTE. However, both genetically predicted whole-body lean mass and appendicular lean mass can causally influence diabetes mellitus (IVW of whole-body lean mass: OR = 0.87, 95% CI = 0.78-0.96, p = 0.008; IVW of appendicular lean mass: OR = 0.71, 95% CI = 0.54-0.94, p = 0.014) and hypertension (IVW of whole-body lean mass: OR = 0.92, 95% CI = 0.87-0.98, p = 0.007; IVW of appendicular lean mass: OR = 0.84, 95% CI = 0.73-0.96, p = 0.013).

CONCLUSIONS

Genetically predicted sarcopenia does not causally influence VTE directly, but it might still have an indirect effect on VTE incidence via diabetes mellitus and hypertension.

Low Daily Step Count Associated with Small Erector Spinae Muscle Area and Sarcopenia in Idiopathic Pulmonary Fibrosis

Objective The daily step count is associated with mortality in idiopathic pulmonary fibrosis (IPF). However, the factors associated with this phenomenon are not yet fully understood. We therefore clarified its association with clinical parameters. Methods Fifty-nine patients with IPF with available data for daily step counts; 6-minute walk distance (6MWD); chest, abdominal, and pelvic computed tomography (CT); pulmonary function; psychological evaluations; and sarcopenia assessments were prospectively enrolled. The daily step count was measured continuously for seven consecutive days. The cross-sectional areas of the erector spinae muscles at the level of the 12th vertebra (ESMCSA) and psoas major muscle volume (PMV) obtained by CT were assessed. Results The average age of the patients was 73.3±8.1 years old, and the percent predicted forced vital capacity was 81.6%±15.8%. The median daily step count was 4,258 (2,155-6,991) steps. The average 6MWD, ESMCSA, and PMV were 413±97 m, 25.5±6.7 cm2, and 270±75.6 cm3, respectively. A linear regression analysis for daily step count showed that the ESMCSA and 6MWD were independent factors for the daily step count, whereas the PMV and skeletal muscle index were not. The daily step count, ESMCSA, and 6MWD were lower in patients with sarcopenia than in those without sarcopenia. Conclusion A lower daily step count was associated with a smaller erector spinae muscle area and sarcopenia in patients with IPF. Further studies are warranted to confirm the importance of physical therapy for muscle strengthening in patients with IPF.