Amount Of Muscle Research Articles

Aging-associated differences between perioral and trunk muscle characteristics.

The physiological and functional changes from aging affect the systemic and swallowing muscles. While ultrasound is used to examine muscle characteristics, no previous studies have examined the relationship between age and perioral and trunk muscle characteristics, including stiffness. This study aimed to investigate the relationship between age and the characteristics of perioral and trunk muscles, including quality, quantity, and stiffness, using ultrasound. A total of 215 participants were recruited for this cross-sectional study: 98 younger adults (20-64 years) and 117 older adults (≥ 65 years). Muscle characteristics were assessed along with data on age, sex, body mass index, and number of teeth. The correlation between age and muscle characteristics was examined. Multiple linear regression was performed with muscle characteristics as dependent variables and age, body mass index, and number of teeth as explanatory variables. We found that only trunk muscle stiffness was associated with age, with a stronger correlation in quality and quantity than perioral muscles. Masseter muscle quality and quantity showed a higher correlation with age than those of the geniohyoid muscle. In conclusion, characteristics of the trunk and perioral muscles exhibit differences in age-related changes, highlighting the importance of maintaining both trunk and perioral muscle activity in older adults to prevent functional decline.

Muscle characteristics of lower limb in association with physical activity in candidates of total knee arthroplasty with knee osteoarthritis

Background&AimsThis study aimed to clarify the association between physical activity (PA) and physical functions, including both muscle quantity and quality of ankle plantar flexor muscles in patients with knee osteoarthritis (OA). MethodsA retrospective cohort study was conducted with ninety-two patients with knee OA. PA, leg muscle cross-sectional area (CSA), knee strength, passive knee angle, and knee pain of the affected side were assessed. PA was assessed by the 2011 Knee Society scoring system. CSA of the quadriceps and ankle plantar flexor muscles on the affected side was measured using a computed tomography image. Based on muscle attenuation assessed with Hounsfield units (HU), the muscle quality of targeted muscle was divided into 4 groups as follows: fat tissue (-190 to -30 HU), very low-density muscle (-29 to -1 HU), low-density muscle (0 to 34 HU), and normal-density muscle (NDM, 35 to 100 HU). The CSA was obtained for each of the 4 groups. Univariate and multivariate linear regression analyses were performed to determine the factors associated with PA. ResultsThe regression analysis revealed that higher PA was independently associated with the NDM CSA of ankle plantar flexor (β = 0.51), higher knee extension strength (β = 0.28), and milder knee pain (β = -0.29) after adjustment with age, sex, height, weight, and body mass index. ConclusionThe present study suggested that NDM CSA of ankle plantar flexor in addition to knee function is one of the factors determining the PA in patients with knee OA.

Muscle Mass and Muscle Strength in Non-Dialysis-Dependent Chronic Kidney Disease Patients.

Background: Sarcopenia is a state with a progressive and generalized loss of skeletal muscle mass and strength. However, muscle strength and muscle mass are different features, which are usually not studied separately. The aim of the study was to investigate anthropometric and clinical correlates and sources of variation in both skeletal muscle mass and muscle strength in chronic kidney disease (CKD). Methods: The study sample consisted of 84 patients with an estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2. Muscle strength was estimated by measuring hand grip strength (HGS). Muscle quantity was measured with bioimpedance spectroscopy (BIS). Serum creatinine, urea, uric acid (UA), and albumin were measured as well. Results: Appendicular skeletal muscle mass (ASM) significantly and positively correlated with body mass, NH weight (normally hydrated weight), height, body mass index (BMI), lean tissue mass (LTM), lean tissue index (LTI), fat mass (FM), and fat tissue index (FTI), and was negatively associated with hydration status. HGS significantly and positively correlated with body mass, NH weight, height, LTM, LTI, and ASM, and was negatively associated with UA and urea. After adjustment for age, sex, and height, HGS remained significantly and negatively related with UA and hydration status. Conclusions: In CKD patients, ASM is determined by anthropometric parameters, but HGS is determined by both anthropometric and clinical variables specific for CKD. In order to study the determinants of HGS in CKD, relationships with HGS should be adjusted for anthropometric variables.

Impedance Spectroscopy Measures of Whole and Segmental Skeletal Muscle Quantity Associated With Strength and Power in Collegiate Ice Hockey Players.

Otremba, JR, Heesch, AJ, Morgan, RM, Poolman, MA, Schindler, GD, and Fitzgerald, JS. Bioelectrical impedance spectroscopy measures of whole and segmental skeletal muscle quantity associated with strength and power in collegiate ice hockey players. J Strength Cond Res XX(X): 000-000, 2024-Bioelectrical impedance spectroscopy (BIS) is a promising monitoring tool for body water compartment assessment, particularly intracellular water (ICW), in which acute decreases are associated with increased muscle damage and reduced function, and chronic changes are associated with muscle quantity. Because little is known about the predictive utility of BIS-derived measures in athletes, this study aimed to assess the association between whole-body and segmental compartment water measured by BIS and maximal-intensity exercise performance in athletes. Twenty-five National Collegiate Athletic Association Division I collegiate hockey players completed 2 consecutive testing sessions. Body water and composition were assessed using a SOZO BIS device. Strength and explosive strength were measured on a force platform during the isometric belt squat and squat jump, respectively. Peak power was assessed using the 6-Second Test on a Wattbike. Pearson's r and partial correlation were used to assess relationships. Select body water and composition BIS variables were strong correlates of strength ( r = 0.51-0.63, p < 0.05), moderate correlates of power ( r = 0.41-0.44, p < 0.05), and lacked association with explosive strength. Segmental leg variables tended to be the strongest correlates of strength and power. Body water and traditional lean mass variables expressed similar predictive utility. Intracellular water/extracellular water lacked associated with exercise performance in bivariate and adjusted models. We provide evidence of the criterion validity of whole-body (i.e., ICW, fat-free mass, skeletal muscle mass [SMM]) and segmental (i.e., leg ICW, leg SMM) BIS variables, related to the quantity of SMM, to predict body-size dependent maximal-intensity exercise performance. Practitioners can use this information to determine which variables to track for performance readiness monitoring.

Association between heart failure in asymptomatic stages and skeletal muscle function assessed by ultrasonography in community-dwelling older adults

BackgroundSymptomatic heart failure (HF) negatively affects the quantity and quality of skeletal muscles. However, the association between asymptomatic HF and skeletal muscle function remains unclear. We aimed to use ultrasonography to elucidate the association between asymptomatic HF and skeletal muscle function in community-dwelling older adults.MethodsThis cross-sectional study comprised community-dwelling older adults aged ≥ 60 years who could perform activities of daily living independently and had never had symptomatic HF (n = 52, 76.3 ± 6.1 years). The participants were classified into three groups namely, non-HF (n = 26), stage A (n = 19), and stage B (n = 7) according to the HF stage criteria of the American Heart Association /American College of Cardiology /Heart Failure Society of America guideline. Skeletal muscle quantity and quality were assessed using ultrasonography (thickness and echo intensity) of the rectus femoris (RF) and vastus intermedius (VI) muscles. The group effects on muscle thickness and echo intensity in each group were assessed using a multivariate analysis.ResultsBoth muscles consistently demonstrated significant group effects on the thickness and echo intensity. Thicknesses of the RF (p = 0.020) and VI (p = 0.035) were lower in the stage B group than that in the non-HF group. The echo intensities in the RF (p = 0.006) and VI (p = 0.009) were higher in the stage B group than that in the non-HF group.ConclusionAsymptomatic HF negatively associated with the characteristics of skeletal muscle function, as assessed by ultrasonography in community-dwelling older adults. The stage B HF contributes to reduced skeletal muscle function as well as symptomatic HF.

The use of portable A-mode ultrasound in appendicular lean mass measurements among older adults: a comparison study with dual-energy X-ray absorptiometry and handgrip strength.

Strength and muscle mass are key factors for the diagnosis of sarcopenia. The EWGSOP2 recommended using ultrasound (US) as a reliable device to measure muscle mass (MM), but A-mode US still needs to be validated for older adults. This study aimed to evaluate the association between measurements of muscle thickness (MT) by portable A-mode US and, muscle quantity by Dual-Energy X-ray absorptiometry (DXA) in older adults. Cross-sectional study, with 115 participants included. Muscle mass was assessed by DXA and MT of the biceps, triceps, anterior thigh, and calf by A-mode US and handgrip strength by a dynamometer. The majority were women (n = 96; 83%), 69 ± 6 years. The MT sum (biceps, triceps, thigh, and calf) assessed by the US was not associated with the appendicular lean mass (ALM) assessed by DXA after controlling for sex and age (R2 = 0.524; p = 0.139; effect size = 0.53). The MT sum biceps and triceps was still significantly associated with MM arms/2 even when controlling for sex and age (which were also significant) (R2 = 0.551; p < 0.001; effect size = 0.56). The MT sum thigh and calf was not associated with MM legs/2 in adjusted models (R2 = 0.499; p = 0.688; effect size = 0.51). This finding shows that the portable A-mode US may not be an appropriate method for estimating MM in extremities (the sum of arms and legs), but can be appropriate for estimating only MM arms in healthy older adults.

Muscle Mass and Glucagon-Like Peptide-1 Receptor Agonists: Adaptive or Maladaptive Response to Weight Loss?

Recent studies have shown that pharmacologic weight loss with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and combination therapies is approaching magnitudes achieved with surgery. However, as more weight loss is achieved, there is concern for potential adverse effects on muscle quantity, composition, and function. This primer aims to address whether muscle-related changes associated with weight loss treatments such as GLP-1 RAs may be maladaptive (ie, adversely affecting muscle health or function), adaptive (ie, a physiologic response to weight loss maintaining or minimally affecting muscle health or function), or perhaps an enhanced response to weight loss (ie, improved muscle health or function after treatment). Based on contemporary evidence with the addition of studies using magnetic resonance imaging, skeletal muscle changes with GLP-1 RA treatments appear to be adaptive: changes in muscle volume z-score indicate a change in muscle volume that is commensurate with what is expected given aging, disease status, and weight loss achieved, and the improvement in insulin sensitivity and muscle fat infiltration likely contributes to an adaptive process with improved muscle quality, lowering the probability for loss in strength and function. Nevertheless, factors such as older age and prefrailty may influence the selection of appropriate candidates for these therapies because of risk for sarcopenia. Several pharmacologic treatments to maintain or improve muscle mass designed in combination with GLP-1-based therapies are under development. For future development of GLP-1-based therapies (and other therapies) designed for weight loss, as well as for patient-centered treatment optimization, the introduction of more objective and comprehensive ways of assessing muscle health (including accurate and meaningful assessments of muscle quantity, composition, function, mobility, and strength) is important for the substantial numbers of patients who will likely be taking these medications well into the future.

Myosteatosis and sarcopenia are linked to autonomous cortisol secretion in patients with aldosterone-producing adenomas.

Patients with adrenal aldosterone-producing adenomas (APA) face elevated cardiovascular risks, especially when cortisol is co-secreted, yet the impact on muscle health remains unclear. Myosteatosis, characterized by fatty infiltration into muscles, is linked to cardiometabolic diseases and decreased survival. We aimed to investigate the association between autonomous cortisol secretion (ACS) in APA and muscle quantity and quality. In this study, we analyzed data from 228 APA patients undergoing laparoscopic adrenalectomy between 2009 and 2024, assessing muscle composition via computed tomography. Intermuscular adipose tissue (IMAT), skeletal muscle area and density, visceral and subcutaneous adipose tissue area at L3 were measured. Comparisons were made between ACS and non-ACS groups. We found that among 228 patients, 76 (33.3%) had ACS. Those with ACS exhibited significantly higher IMAT area (P = 0.042) and lower skeletal muscle area (P = 0.002) and density (P < 0.001). Multivariable regression confirmed ACS positively associated with IMAT area and negatively associated with skeletal muscle area and density. At 1-year follow-up, ACS patients (n = 15) experienced decreased IMAT area (P = 0.001) and increased skeletal muscle area (P = 0.031) post-adrenalectomy, while those without ACS (n = 29) showed no IMAT change but increased visceral (P < 0.001) and subcutaneous (P = 0.008) adipose tissue area. In summary, myosteatosis and sarcopenia are linked to ACS in APA patients, and these parameters improve following adrenalectomy.

Advancements in sarcopenia diagnosis: from imaging techniques to non-radiation assessments.

Sarcopenia is a prevalent condition with significant clinical implications, and it is expected to escalate globally, demanding for effective diagnostic strategies, possibly at an early stage of the disease. Imaging techniques play a pivotal role in comprehensively evaluating sarcopenia, offering insights into both muscle quantity and quality. Among all the imaging techniques currently used for the diagnosis and follow up of sarcopenia, it is possible to distinguish two classes: Rx based techniques, using ionizing radiations, and non-invasive techniques, which are based on the use of safe and low risk diagnostic procedures. Dual-energy x-ray Absorptiometry and Computed Tomography, while widely utilized, entail radiation exposure concerns. Ultrasound imaging offers portability, real-time imaging, and absence of ionizing radiation, making it a promising tool Magnetic Resonance Imaging, particularly T1-weighted and Dixon sequences, provides cross- sectional and high-resolution images and fat-water separation capabilities, facilitating precise sarcopenia quantification. Bioelectrical Impedance Analysis (BIA), a non-invasive technique, estimates body composition, including muscle mass, albeit influenced by hydration status. Standardized protocols, such as those proposed by the Sarcopenia through Ultrasound (SARCUS) Working Group, are imperative for ensuring consistency across assessments. Future research should focus on refining these techniques and harnessing the potential of radiomics and artificial intelligence to enhance diagnostic accuracy and prognostic capabilities in sarcopenia.

Glucagon-like peptide-1 receptor agonist-based agents and weight loss composition: Filling the gaps.

Excess adiposity is at the root of type 2 diabetes (T2D). Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as first-line treatments for T2D based on significant weight loss results. The composition of weight loss using most diets consists of <25% fat-free mass (FFM) loss, with the remainder from fat stores. Higher amounts of weight loss (achieved with metabolic bariatric surgery) result in greater reductions in FFM. Our aim was to assess the impact that GLP-1RA-based treatments have on FFM. We analysed studies that reported changes in FFM with the following agents: exenatide, liraglutide, semaglutide, and the dual incretin receptor agonist tirzepatide. We performed an analysis of various weight loss interventions to provide a reference for expected changes in FFM. We evaluated studies using dual-energy X-ray absorptiometry (DXA) for measuring FFM (a crude surrogate for skeletal muscle). In evaluating the composition of weight loss, the percentage lost as fat-free mass (%FFML) was equal to ΔFFM/total weight change. The %FFML using GLP-1RA-based agents was between 20% and 40%. In the 28 clinical trials evaluated, the proportion of FFM loss was highly variable, but the majority reported %FFML exceeding 25%. Our review was limited to small substudies and the use of DXA, which does not measure skeletal muscle mass directly. Since FFM contains a variable amount of muscle (approximately 55%), this indirect measure may explain the heterogeneity in the data. Assessing quantity and quality of skeletal muscle using advanced imaging (magnetic resonance imaging) with functional testing will help fill the gaps in our current understanding.

Muscle Makers: Evaluating a 10-Week Strength and Nutrition Programme's Impact on Sarcopenia

Abstract Background Sarcopenia is a progressive skeletal muscle disorder characterized by loss of muscle mass and strength, leading to adverse outcomes like physical disability, poor quality of life, and death. The European Working Group on Sarcopenia in Older People (EWGSOP) identifies sarcopenia using criteria including low muscle strength, quantity, quality, and performance. This highlights the importance of early detection and intervention strategies, such as the physiotherapy-led Muscle Makers programme —a 10-week outpatient Progressive Resistance Training (PRT) program with fortnightly Clinical Nutrition input. This data collection aimed to evaluate the programme's effectiveness over a 6-month period. Methods Data was collected on all participants who attended Muscle Makers (one 1-hour session/week) between September 2023 and February 2024. Analysis included participants with both pre- and post-10-week programme outcome measures completed. Data was collected and analysed using MS Excel. Outcome Measures (OCMsused: Timed Up and Go (TUG) and 5-time sit to stand (5TST).Inclusion: Participants with both pre- and post-OCMscompletedExclusion: Participants without pre/post OCMsNon-normally distributed data was log-transformed prior to statistical testing.Results: Number of participants fitting inclusion criteria: 44 (Male: 20, Female: 24)Average age: 80.6 yearsAverage sarcopenia score (SARC F): 4.04 (probable sarcopenia)Average number of falls in the past 12 months: 1.56Average number of classes attended: 8.12 Data Results Conclusion The participants in the Muscle Makers programme achieved significant improvements in both the 5TST and TUG tests, demonstrating enhanced lower body strength, balance, and overall functional mobility. These improvements suggest that the 10-week strength and nutrition intervention effectively mitigates the effects of sarcopenia, highlighting the potential of targeted exercise and nutritional strategies in managing and potentially reversing the progression of this condition.

Cross-Cultural Adaptation and Clinical Validation of the Mini Sarcopenia Risk Assessment Questionnaire in Community-Dwelling Spanish Older Adults

(1) Background: The aim was to analyze the reliability and validity of the Spanish version of the Mini Sarcopenia Risk Assessment (MSRA) in older adults. (2) Methods: A total of 136 participants (72.24 ± 5.21 years, 68.38% women) took part in the study. The MSRA includes two questionnaires with seven (MSRA-7) and five items (MSRA-5). First, reliability (inter-rater and test–retest) of the Spanish MSRA was studied, and then the total scores were compared with the presence of sarcopenia according to three different diagnostic criteria and with other parameters related to sarcopenia (clinical validation). (3) Results: The analysis showed excellent inter-rater and test–retest reliability. As for the clinical validation, and regardless of the criteria, both questionnaires had a high sensitivity (81.82–88.89% for the MSRA-5 and 90.91–94.44% for the MSRA-7), while the MSRA-5 showed a better specificity (32.00–33.90%) than the MSRA-7 (20.80–22.88%). Predictive positive values ranged from 9.57–17.02% (MSRA-5) and 9.17–15.54% (MSRA-7), while predictive negative values were high for both the MSRA-5 (95.24%) and the MSRA-7 (96.30–96.43%). The accuracy was better for the MSRA-5 (36.03–41.18%) than the MSRA-7 (26.47–32.35%), as well as the area under the curve (0.67–0.76 vs. 0.65–0.73, respectively). Higher MSRA-5 and MSRA-7 total scores significantly correlated with greater muscle strength, quantity and gait speed. (4) Conclusions: The adaptation of the Spanish MSRA questionnaires was successfully performed, and they are reliable and clinically valid tools for assessing sarcopenia.

Age-induced changes in skeletal muscle mitochondrial DNA synthesis, quantity, and quality in genetically unique rats

AbstractMitochondrial genomic integrity is a key element of physiological processes and health. Changes in the half-life of the mitochondrial genome are implicated in the generation and accumulation of age-induced mitochondrial DNA (mtDNA) mutations, which are implicated in skeletal muscle aging and sarcopenia. There are conflicting data on the half-life of mtDNA, and there is limited information on how aging affects half-life in skeletal muscle. We hypothesized that skeletal muscle mtDNA synthesis rates would decrease with age in both female and male rats concomitant with changes in mtDNA integrity reflected in mtDNA copy number and mutation frequency. We measured mitochondrial genome half-life using stable isotope labeling over a period of 14 days and assessed mtDNA copy number and deletion mutation frequency using digital PCR in the quadriceps muscle of 9-month-old and 26-month-old male and female OKC-HET rats. We found a significant age-related increase in mtDNA half-life, from 132 days at 9 months to 216 days at 26 months of age in OKC-HET quadriceps. Concomitant with the increase in mtDNA half-life, we found an age-related increase in mtDNA deletion mutation frequency in both male and female rats. Notably, 26-month-old female rats had a lower mutation frequency than male rats, and there were no changes in mtDNA copy number with sex, age, or mitochondrial genotype. These data reveal several key findings: (1) mtDNA turnover in rat skeletal muscle decreases with age, (2) mtDNA half-lives in skeletal muscle are approximately an order of magnitude longer than what is reported for other tissues, and (3) muscle mtDNA turnover differs significantly from the turnover of other mitochondrial macromolecules including components of the mitochondrial nucleoid. These findings provide insight into the factors driving age-induced mtDNA mutation accumulation, which contribute to losses of mitochondrial genomic integrity and may play a role in skeletal muscle dysfunction.

A sex-oriented analysis concerning skeletal muscle quantity and quality and associations to quality of life in hospitalized patients with cirrhosis

BackgroundThere is a paucity of data regarding sex-oriented analyses of connection between muscle quantity and quality and health-related quality of life (HRQoL), taking into account the pathophysiological differences of sarcopenia/myosteatosis in males versus females. We sought to investigate the associations between skeletal muscle index (SMI)-defined sarcopenia and intramuscular adipose tissue content (IMAC)-defined myosteatosis and EuroQol-5D (EQ-5D)-defined HRQoL in patients with decompensated cirrhosis concerning sex disparities.MethodsTotally, 382 patients were enrolled. The relationship between SMI/IMAC and HRQoL was evaluated with restricted cubic spline and Pearson correlation analyses. Furthermore, association between SMI or sarcopenia and EQ-5D utility index was determined by multiple linear regression, adjusted for age, BMI and concurrent disease severity.ResultsThe study population comprised evenly distributed male and female patients (190: 192), mean age 61.9 years. The prevalence of sarcopenia (40.5 versus 9.9%, P < 0.001) and SMI (48.8 versus 42.2 cm2/m2, P < 0.001) were significantly higher in males relative to females, with comparable myosteatosis prevalence (15.3 versus 16.7%, P = 0.708). Self-care, usual activities and pain within EQ-5D scale were more prevalent in the sarcopenia compared with non-sarcopenia groups across entire population and stratified by sex. The SMI values exhibited a significantly linear correlation with EQ-5D utility index in male but not female patients (P for non-linearity = 0.281). In multiple analysis, SMI or the presence of sarcopenia was both significantly associated with EQ-5D utility index. Subgroup analyses unveiled no discernible interactions between sarcopenia and EQ-5D utility index.ConclusionsMuscle quantity measured by SMI was associated with declined HRQoL in males rather than females, whereas no associations were found regarding muscle quality measured by IMAC in both sexes. It is tempting to manage sarcopenia by increasing SMI levels as high as possible in hopes of achieving better health consequence. Our findings represent the importance of connecting CT-demarcated body composition abnormalities to meaningful patient-centered outcomes. Future targeted studies with sizable multi-center populations are warranted to clarify this causality, and in consequence develop optimized intervention against sarcopenia/myosteatosis or key determinants concerning impaired HRQoL.

Evaluation of Sonographic Muscle Measurement Using Established Muscle Markers.

Loss of muscle quantity and function is associated with frailty and reduced quality of life. Sonography is a simple option to quantify muscle mass, which could be included into routine diagnostic workup. This study was designed to prospectively evaluate sonographic measurement and to compare it with established measurements of muscle quantity and function. Between March 2020 and May 2022, 723 patients were enrolled in the study. Psoas muscle area index (PMAI) and psoas muscle thickness height index (PMTI) were quantified. Thigh muscle thickness indices (TMTI) were either measured without compression (fTMTI) or under compression (cTMTI). Variation coefficient (VC) as well as intra- and inter-observer reliability were analyzed. The reliability and reproducibility of the sonographic morphometry were assessed using two examiners. Sonographic morphometry was compared with established measurements of muscle using computed tomography and hand grip strength, respectively. In 156 patients, sonographic indices were compared with corresponding CT indices. Of the 723 patients included, sonographic indices were compared with hand strength in 429 patients. Interobserver and intraobserver variability showed better results for the femur indices than for the psoas indices (correlation coefficient: 0.8697/0.9118 vs 0.7502/0.7319). Psoas muscle indices correlated best with the reference standard of the SMI. The optimal cut-off for each muscle index for determining muscle loss according to the SMI and hand grip strength was calculated. Sonography can simplify muscle measurement and should be used in the future. Sonographic muscle indices have the potential to simplify evaluation, especially in risk groups such as patients with liver cirrhosis or other wasting disorders.

Effects of muscle quantity, muscle quality, and phase angle on whole-body reaction time in 5164 adults aged 20-91years.

Muscle quantity, defined as appendicular lean mass (ALM); muscle quality, defined as the ratio of muscle strength to ALM; and bioelectrical impedance analysis (BIA)-derived phase angle (PhA) are determinants of physical performance. We examined whether muscle quality indices were significant predictors of the whole-body reaction time (WBRT) in healthy female and male adults aged 20-91years. Data from 5164 adults (2869 women and 2295 men; mean age ± standard deviation, 60.9 ± 15.6years) were analyzed. Height and weight were measured, and body mass index was calculated. ALM was estimated using a previously validated 8-electrode multi-frequency BIA. PhA was measured at 50kHz using a BIA device. Knee extension strength (KES), leg extension power (LEP), and flexibility were examined. The ALM to weight (ALM/weight), KES to ALM (KES/ALM), and LEP to KES (LEP/KES) ratios were calculated. In the WBRT test, participants were asked to stand on a force plate and jump upright as quickly as possible in response to a light stimulus. The WBRT was divided into the response initiation and motion execution phases. ALM/weight, KES/ALM, LEP/KES, PhA, and flexibility were significant independent predictors of WBRT and the time of the motion execution phase (p < 0.001). However, PhA was not a significant predictor of the time of response initiation phase. Muscle quantity (ALM/weight), muscle quality (KES/ALM and LEP/KES), PhA, and flexibility are determinants of WBRT test performance, particularly in the motion execution phase.

Phase angle measured by bioelectrical impedance analysis in patients with chronic obstructive pulmonary disease: Associations with physical inactivity and frailty

BackgroundFactors associated with early-stage frailty (pre-frailty) in patients with chronic obstructive pulmonary disease (COPD) remain unestablished. In addition to skeletal muscle quantity, skeletal muscle dysfunction can be estimated using an angular metric from bioelectrical impedance analyzer (BIA), termed the phase angle, that reflects cell membrane reactance representing the structural stability. This study examined whether the phase angle was more closely associated with pre-frailty compared with skeletal muscle quantity in patients with COPD. MethodsThis cross-sectional analysis included stable smokers with and without COPD whose frailty status was assessed using the Japanese version of the Cardiovascular Health Study criteria. The phase angle and skeletal muscle index (SMI) were measured using BIA, and physical activity over one week was assessed using triaxial accelerometers. ResultsA total of 159 patients were categorized into robust, pre-frail, and frail groups (n = 38, 92, and 29, respectively). The phase angle was significantly smaller in the pre-frail and frail groups than in the robust group after adjusting for age, sex, height, body mass index, smoking history, and lung function. In contrast, SMI did not differ between the robust and pre-frail groups. When combining the pre-frail and frail groups into a non-robust group, 4.8° was determined as the cutoff phase angle value to identify non-robust status. A phase angle <4.8° was associated with shorter durations of moderate-intensity physical activity but not with light physical activity. ConclusionsA smaller phase angle was associated with pre-frailty and impaired moderate-intensity physical activity in smokers with and without COPD.

Effect of the Japanese herbal medicine Hochuekkito for systemic inflammation, prognostic nutrition index, and body composition status in patients with gastrointestinal cancer

A systemic inflammatory response via host-tumor interactions is a cancer hallmark that plays a pivotal role in the pathogenesis of malnutrition and sarcopenia in patients with malignancies. Hochuekkito (TJ-41) is a traditional Japanese herbal medicine that modulates inflammation in patients with various chronic inflammatory diseases. However, the clinical efficacy of TJ-41 in patients with malignancies remains unclear. We systemically analyzed chronological changes in levels of systemic inflammatory parameters, nutrition-related parameters, and body composition status in 99 patients who received TJ-41 treatment for more than 3 months. The cohort comprised 56 patients with gastrointestinal cancer (Cancer Cohort) and 43 with other diseases (Other Disease Cohort). We also performed invivo experiments in mice to validate the clinical findings. Despite no significant changes in serum albumin concentration and prognostic nutrition index, the serum C-reactive protein (CRP) concentration significantly decreased in a time-dependent manner in all patients. However, the serum CRP concentration significantly decreased during TJ-41 treatment in the Cancer Cohort but not the Other Disease Cohort. Furthermore, downregulation of CRP during TJ-41 treatment occurred only in patients with metastases. The psoas muscle index, as a muscle quantity marker, was significantly lower in the CRP-increased group compared with the CRP-decreased group during TJ-41 treatment. Invivo experiments using a Colon-26 syngeneic model showed that the plasma CRP, amyloid A, and interleukin-6 concentrations were significantly lower in the TJ-41 group than the control group. TJ-41 might be useful as part of multimodality therapy for gastrointestinal cancer, especially in patients with metastases.

Myosteatosis: an underrecognized risk factor for mortality in non-dialysis chronic kidney disease patients.

Low muscle mass quantity and quality (myosteatosis) can be evaluated by computed tomography (CT)by measuring skeletal muscle area and muscular attenuation, respectively, at the third lumbar vertebra. We aimed to define cut-off points of skeletal muscle area and muscular attenuation to predict mortality in non-dialysis chronic kidney disease (CKD)patients. We conducted a retrospective study including non-dialysis CKD patients over two years, who underwent an opportunistic computed tomography within a two year period, and for whom creatinine was measured within 90days of CT. Skeletal muscle area was normalized for stature to calculate the skeletal muscle index. Area under the receiver operating characteristic (AuROC) curve and Youden's index were used, to identify the cut-point, separatelyaccording to sex. One hundred sixty-seven patients (50.9% male, mean age of 68.3 ± 16.4years) were included, most with CKD stages 3 and 4. During a median follow-up of 4.9 (4.2) years, 39 (23.4%) patients died. Muscular attenuation showed a better ability to predict mortality (AuROC curve 0.739 [95% CI 0.623-0.855] in women and 0.744 in men [95% CI 0.618-0.869]) than skeletal muscle index (AuROC curve 0.491 [95% CI 0.332-0.651] in women and 0.711 [95% CI 0.571-0.850] in men). For muscular attenuation, the best cut-off values to predict mortality were 27.56 Hounsfield units in women and 24.58 Hounsfield units in men. For skeletal muscle index, the best cut-off values were 38.47 cm2/m2 in women and 47.81 cm2/m2 in men. In univariable Cox-regression both low muscle mass and myosteatosis were associated with increased mortality. In multivariable Cox-regression models only myosteatosismaintained a significant association with mortality (Hazard Ratio 2.651 (95% CI 1.232-5.703, p = 0.013)). We found sex-specific cut-off values for muscle parameters using CT analysis in non-dialysis CKD patients that were associated with mortality. In this population, myosteatosis may be more closely associated with mortality than muscle quantity.

Association of muscle quantity and quality with knee extension strength in knee osteoarthritis: the Nagahama study.

We aimed to examine whether lower-limb muscle quantity and quality assessed by bioelectrical impedance analysis (BIA) were associated with knee extension strength and if the association differed with knee osteoarthritis (OA) severity. We included 1,525 participants (63.6% women; mean age, 68.0±5.3 years) from the Nagahama Prospective Cohort. Knee extension strength was measured during maximum voluntary isometric contraction. Lower limb muscle mass and extracellular-to-intracellular water (ECW/ICW) ratio were used as indicators of muscle quantity and quality, respectively, and assessed via a BIA device. We executed multiple linear regression analyses to investigate the association of muscle quantity and quality with knee extension strength. Additionally, participants were classified into three groups with respect to OA severity and symptoms: control, early, and advanced OA groups; subgroup analyses were also executed. The muscle mass (p<0.001) and ECW/ICW ratio (p=0.009) were significantly associated with knee extension strength. In the subgroup analysis, the muscle mass was significantly associated with knee extension strength (p<0.001), but there was no association between ECW/ICW ratio and knee extension strength (p=0.731) in the control group. In the early and advanced OA groups, the muscle mass (both p<0.001) and ECW/ICW ratio (early OA: p=0.034, advanced OA: p=0.015) were significantly associated with knee extension strength. Lower limb muscle quality was associated with knee extension strength, and the association was stronger in patients with knee OA. These findings suggest that both muscle quantity as well as quality should be assessed to better understand muscle function in patients with knee OA.