Thigh muscle composition changes in knee osteoarthritis patients during weight loss: Sex-specific analysis using data from osteoarthritis initiative.

OBJECTIVES: Sex of patients with knee osteoarthritis (KOA) may impact changes in thigh muscle composition during weight loss, the most well-known disease-modifying intervention. We investigated longitudinal sex-based changes in thigh muscle quality during weight loss in participants with KOA. METHODS: Using Osteoarthritis Initiative (OAI) cohort data, we included females and males with baseline radiographic KOA who experienced > 5 % reduction in Body Mass Index (BMI) over four years. Using a previously validated deep-learning algorithm, we measured Magnetic Resonance Imaging (MRI)-derived biomarkers of thigh muscles at baseline and year-4. Outcomes were the intra- and inter-muscular adipose tissue (Intra-MAT and Inter-MAT) and contractile percentage of thigh muscles between females and males. The analysis adjusted for potential confounders, such as demographics, risk factors, BMI change, physical activity, diet, and KOA status. RESULTS: A retrospective selection of available thigh MRIs from KOA participants who also had a 4-year weight loss (>5 % of BMI) yielded a sample comprising 313 thighs (192 females and 121 males). Female and male participants exhibited a comparable degree of weight loss (females: -9.72 ± 4.38, males: -8.83 ± 3.64, P-value=0.060). However, the changes in thigh muscle quality were less beneficial for females compared to males, as shown by a less degree of longitudinal decrease in Intra-MAT (change difference,95 %CI: 783.44 mm2/4-year, 505.70 to 1061.19, P-value<0.001) and longitudinal increase in contractile percentage (change difference,95 %CI: -3.9 %/4-year, -6.5 to -1.4, P-value=0.019). CONCLUSIONS: In participants with KOA and 4-year weight loss, the longitudinal changes in thigh muscle quality were overall beneficial but to a less degree in females compared to males. Further research is warranted to investigate the underlying mechanisms and develop sex-specific interventions to optimize muscle quality during weight loss.

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.

Muscle quality and major adverse cardiovascular events in post-acute myocardial infarction: A prospective cohort study.

BACKGROUND & AIMS: Functional muscle quality, as assessed through the muscle quality index (MQI), represents a contemporary method to measure the capacity to generate force. Despite its potential, the prognostic significance of MQI remains uncertain in various clinical conditions, particularly among patients following acute myocardial infarction (AMI). In light of this, our study sought to evaluate the prognostic relevance of MQI concerning major adverse cardiovascular events (MACE) in patients following AMI. METHODS AND RESULTS: This is a secondary analysis of a prospective cohort study that included subjects aged ≥20 years from a Cardiovascular Unit Hospital. Functional muscle quality was estimated using MQI, defined as the ratio of handgrip strength (HGS) to muscle mass (MM) derived from bioelectrical impedance analysis. The outcomes included prolonged length of hospital stay, new adverse cardiovascular events (AMI, stroke and hospital readmission for unstable angina), and cardiovascular mortality. A composite score comprising all adverse events over the 1-year follow-up was calculated and defined as MACE. This study included 163 patients, with a median age of 61 years (IQ: 54-69 years), and the majority consisted of males (76.1%). Individual components of the functional muscle quality (HGS and MM) were not associated with any of the adverse outcomes. Only MQI was associated mortality over the 1-year follow-up. For each increase in MQI, the hazard of mortality decreases: adjusted HR: 0.08 (95% CI 0.01-0.84). CONCLUSION: Functional muscle quality assessed by the MQI may be a valuable clinical predictor of 1-year cardiovascular mortality in patients hospitalized post-AMI.

Carnosine supplementation improves glucose control in adults with pre-diabetes and type 2 diabetes: A randomised controlled trial.

BACKGROUND AND AIMS: Type 2 diabetes (T2DM) is a major cause of morbidity and mortality globally. Carnosine, a naturally occurring dipeptide, has anti-inflammatory, antioxidant, and anti-glycating effects, with preliminary evidence suggesting it may improve important chronic disease risk factors in adults with cardiometabolic conditions. METHODS AND RESULTS: In this randomised controlled trial, 43 adults (30%F) living with prediabetes or T2DM consumed carnosine (2 g) or a matching placebo daily for 14 weeks to evaluate its effect on glucose metabolism assessed via a 2-h 75 g oral glucose tolerance test. Secondary outcomes included body composition analysis by dual energy x-ray absorptiometry (DEXA), calf muscle density by pQCT, and anthropometry. Carnosine supplementation decreased blood glucose at 90 min (-1.31 mmol/L; p = 0.02) and 120 min (-1.60 mmol/L, p = 0.02) and total glucose area under the curve (-3.30 mmol/L; p = 0.04) following an oral glucose tolerance test. There were no additional changes in secondary outcomes. The carnosine group results remained significant before and after adjustment for age, sex, and change in weight (all>0.05), and in further sensitivity analyses accounting for missing data. There were no significant changes in insulin levels. CONCLUSION: This study provides preliminary support for larger trials evaluating carnosine as a potential treatment for prediabetes and the initial stages of T2DM. Likely mechanisms may include changes to hepatic glucose output explaining the observed reduction in blood glucose without changes in insulin secretion following carnosine supplementation.

Nonalcoholic Fatty Liver Disease, Bone and Muscle Quality in Prolactinoma: A Pilot Study.

OBJECTIVE: Hyperprolactinemia has negative impacts on metabolism and musculoskeletal health. In this study, individuals with active prolactinoma were evaluated for nonalcoholic fatty liver disease (NAFLD) and musculoskeletal health, which are underemphasized in the literature. METHODS: Twelve active prolactinoma patients and twelve healthy controls matched by age, gender, and BMI were included. Magnetic resonance imaging-proton density fat fraction (MRI-PDFF) was used to evaluate hepatic steatosis and magnetic resonance elastography (MRE) to evaluate liver stiffness measurement (LSM). Abdominal muscle mass, and vertebral MRI-PDFF was also evaluated with MRI. Body compositions were evaluated by dual energy X-ray absorptiometry (DXA). The skeletal muscle quality (SMQ) was classified as normal, low and weak by using "handgrip strength/appendicular skeletal muscle mass (HGS/ASM)" ratio based on the cut-off values previously stated in the literature. RESULTS: Prolactin, HbA1c and CRP levels were higher in prolactinoma patients (p<0.001, p=0.033 and p=0.035, respectively). The median MRI-PDFF and MRE-LSM were 3.0% (2.01-15.20) and 2.22 kPa (2.0-2.5) in the prolactinoma group and 2.5% (1.65-10.00) and 2.19 kPa (1.92-2.54) in the control group, respectively and similiar between groups. In prolactinoma patients, liver MRI-PDFF showed a positive and strong correlation with the duration of disease and traditional risk factors for NAFLD. Total, vertebral and pelvic bone mineral density was similar between groups, while vertebral MRI-PDFF tended to be higher in prolactinoma patients (p=0.075). Muscle mass and strength parameters were similar between groups, but HGS/ASM tended to be higher in prolactinoma patients (p=0.057). Muscle mass was low in 33.3% of prolactinoma patients and 66.6 of controls. According to SMQ, all prolactinoma patients had normal SMQ, whereas 66.6% of the controls had normal SMQ. CONCLUSION: Prolactinoma patients demonstrated similar liver MRI-PDFF and MRE-LSM to controls despite their impaired metabolic profile and lower gonadal hormone levels. Hyperprolactinemia may improve muscle quality in prolactinoma patients despite hypogonadism.

Sarcopenic obesity in nursing home residents: a multi-center study on diagnostic methods and their association with instrumental activities of daily living.

BACKGROUND: Sarcopenic obesity (SO) in nursing home residents is rarely studied. We aimed to evaluate and compare the prevalence and consistency of different SO diagnostic methods and to investigate which criterion demonstrated a stronger association with instrumental activities of daily living (IADL) disability. METHODS: We consecutively recruited older adults aged ≥ 60 years, residing in 15 nursing homes in Zigong City, China. Sarcopenia obesity was defined according to the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity criteria (SOESPEN), recommending skeletal muscle mass (SMM) adjusted by body weight (SMM/W) to identify low muscle mass. Further, we adapted ESPEN criteria (SOESPEN-M) by employing SMM adjusted by body mass index (SMM/BMI). RESULTS: We included 832 participants (median age 73.0 years, 296 women). The prevalence of SOESPEN and SOESPEN-M was 43.5% and 45.3%, respectively. SOESPEN showed good consistency with SOESPEN-M (Cohen's kappa = 0.759). More than one-third of participants in the normal weight group were diagnosed with SOESPEN or SOESPEN-M. Even within the underweight group, the prevalence of SOESPEN and SOESPEN-M was 8.9% and 22.2%, respectively. Participants with IADL disability had significantly lower SMM/W and SMM/BMI, but higher fat mass percentage of body weight (FM%) than participants without IADL disability. After full adjustment for potential confounders, SOESPEN-M (OR 1.68, 95% CI 1.21 to 2.32), but not SOESPEN (OR 1.28, 95% CI 0.93 to 1.75), remained significantly associated with IADL disability. CONCLUSIONS: Both SOESPEN and SOESPEN-M showed a high prevalence among nursing home residents, even among individuals with underweight or normal weight. While SOESPEN had a good consistency with SOESPEN-M, only SOESPEN-M was independently associated with IADL disability. Screening and diagnosis of SO should be conducted in nursing home residents irrespective of BMI.

Non invasive techniques for direct muscle quality assessment after exercise intervention in older adults: a systematic review.

BACKGROUND: The aging process induces neural and morphological changes in the human musculoskeletal system, leading to a decline in muscle mass, strength and quality. These alterations, coupled with shifts in muscle metabolism, underscore the essential role of physical exercise in maintaining and improving muscle quality in older adults. Muscle quality's morphological domain encompasses direct assessments of muscle microscopic and macroscopic aspects of muscle architecture and composition. Various tools exist to estimate muscle quality, each with specific technical requirements. However, due to the heterogeneity in both the studied population and study methodologies, there is a gap in the establishment of reference standards to determine which are the non-invasive and direct tools to assess muscle quality after exercise interventions. Therefore, the purpose of this review is to obtain an overview of the non-invasive tools used to measure muscle quality directly after exercise interventions in healthy older adults, as well as to assess the effects of exercise on muscle quality. MAIN TEXT: To address the imperative of understanding and optimizing muscle quality in aging individuals, this review provides an overview of non-invasive tools employed to measure muscle quality directly after exercise interventions in healthy older adults, along with an assessment of the effects of exercise on muscle quality. RESULTS: Thirty four studies were included. Several methods of direct muscle quality assessment were identified. Notably, 2 studies harnessed CT, 20 utilized US, 9 employed MRI, 2 opted for TMG, 2 adopted myotonometry, and 1 incorporated BIA, with several studies employing multiple tests. Exploring interventions, 26 studies focus on resistance exercise, 4 on aerobic training, and 5 on concurrent training. CONCLUSIONS: There is significant diversity in the methods of direct assessment of muscle quality, mainly using ultrasound and magnetic resonance imaging; and a consistent positive trend in exercise interventions, indicating their efficacy in improving or preserving muscle quality. However, the lack of standardized assessment criteria poses a challenge given the diversity within the studied population and variations in methodologies.. These data emphasize the need to standardize assessment criteria and underscore the potential benefits of exercise interventions aimed at optimizing muscle quality.

Resistance training effects on pubertal children with a risk of developing pediatric dynapenia.

PURPOSE: Many modern-day children are at risk of pediatric dynapenia (muscle weakness). We examined the effects of a 12-week resistance training (RT) program on neuromuscular function and body composition parameters in pubertal children with a risk of dynapenia. METHODS: Twelve children (13.4 ± 0.9 y) with dynapenia performed a progressive RT program consisting of knee extension and flexion, bench press, abdominal crunch, back extension, lateral pull-down, elbow flexion, and upright row (1-2 sets of 10-15 repetitions/exercise) twice/week for 12 weeks. Outcome measures included one-repetition maximum (1-RM) strength, maximal voluntary isometric contraction (MVIC) torque, rate of torque development (RTD), electromyographic (EMG) activity, muscle thickness (MT), muscle quality (MQ) assessed by echo intensity (MQEI) of the knee extensors and specific tension of MVIC torque to thigh fat-free mass (MQST), and total and regional body and bone composition assessed by dual-energy X-ray absorptiometry. Changes in the measures before and after the 12-week RT and associations among the measures were analyzed by linear mixed models. RESULTS: Significant (p < 0.05) increases in 1-RM (63.9 ± 4.5%), MVIC torque (16.3 ± 17.8%), MT (18.8 ± 5.5%) and MQ (MQEI: -25.9 ± 15.2%; MQST: 15.1 ± 18.8%;) were evident from pre- to post-training. Total fat-free mass (FFM) increased by 2.3 ± 3.2% from baseline (p = 0.01), but no changes (p > 0.05) in the other measures were observed. Significant (p < 0.05) associations between the changes in 1-RM and/or MVIC torque and the changes in quadriceps MT, MQEI, MQST and total body FFM were evident. CONCLUSIONS: The 12-week RT was effective for improving neuromuscular and body composition parameters, and thereby reversed the risk of pediatric dynapenia.

One-leg standing time is a simple measure for loss of skeletal muscle mass and fat deposition in muscle: the J-SHIPP study.

BACKGROUNDS: One-leg standing time (OLST) has been frequently used physical performance measure; however, what muscular characteristics OLST represents remains uncertain. AIM: This cross-sectional study aimed to investigate the association between OLST and muscle characteristics to clarify the possibility of using OLST as a physical performance measure. METHODS: Study participants comprised 1144 older adults aged 65 years or older. Computed tomography images provided mid-thigh skeletal muscle cross-sectional area and mean attenuation value. OLST was measured for a maximum of 60 s. Static postural instability was assessed using a posturography. RESULTS: A frequency of OLST < 20 s was increased by quartiles of muscle cross-sectional area (Q1: 33.6, Q2: 12.8, Q3: 13.6, Q4: 11.9%, P < 0.001) and mean attenuation value (Q1: 32.3, Q2: 21.7, Q3: 14.3, Q4: 7.7%, P < 0.001). Results of the multinomial regression analysis indicated that muscle cross-sectional area and mean attenuation value were independently associated with an OLST of less than 20 s. The crude odds ratio of OLST less than 20 s for the lowest quartiles of both cross-sectional area and mean attenuation value was 4.19 (95% CI: 3.01 - 5.84). The cross-sectional area of muscles with greater fat deposition was inversely associated with OLST, while that with smaller fat deposition showed a positive association with OLST, indicating why mean attenuation value and cross-sectional area were independently associated with OLST. No clear relationship was observed with static postural instability. CONCLUSION: OLST was a simply measurable quantifiable physical measure representing the loss of muscle mass and quality in older adults.

Statin use and longitudinal changes in quantitative MRI-based biomarkers of thigh muscle quality: data from Osteoarthritis Initiative.

OBJECTIVE: To assess whether changes in MRI-based measures of thigh muscle quality associated with statin use in participants with and without/at-risk of knee osteoarthritis. METHODS: This retrospective cohort study used data from the Osteoarthritis Initiative study. Statin users and non-users were matched for relevant covariates using 1:1 propensity-score matching. Participants were further stratified according to baseline radiographic knee osteoarthritis status. We used a validated deep-learning method for thigh muscle MRI segmentation and calculation of muscle quality biomarkers at baseline, 2nd, and 4th visits. Mean difference and 95% confidence intervals (CI) in longitudinal 4-year measurements of muscle quality biomarkers, including cross-sectional area, intramuscular adipose tissue, contractile percent, and knee extensors and flexors maximum and specific contractile force (force/muscle area) were the outcomes of interest. RESULTS: After matching, 3772 thighs of 1910 participants were included (1886 thighs of statin-users: 1886 of non-users; age: 62 ± 9 years (average ± standard deviation), range: 45-79; female/male: 1). During 4 years, statin use was associated with a slight decrease in muscle quality, indicated by decreased knee extension maximum (mean-difference, 95% CI: - 1.85 N/year, - 3.23 to - 0.47) and specific contractile force (- 0.04 N/cm2/year, - 0.07 to - 0.01), decreased thigh muscle contractile percent (- 0.03%/year, - 0.06 to - 0.01), and increased thigh intramuscular adipose tissue (3.06 mm2/year, 0.53 to 5.59). Stratified analyses showed decreased muscle quality only in participants without/at-risk of knee osteoarthritis but not those with established knee osteoarthritis. CONCLUSIONS: Statin use is associated with a slight decrease in MRI-based measures of thigh muscle quality over 4 years. However, considering statins' substantial cardiovascular benefits, these slight muscle changes may be relatively less important in overall patient care.

Investigating the relationship between quantitative-based ultrasound and MRI estimations of rotator cuff fatty infiltration.

INTRODUCTION: Fatty infiltration (FI) of the rotator cuff has important clinical implications. Quantitatively estimating FI using ultrasound (US) has considerable benefits for assessing FI in a non-invasive, accessible manner. This research investigated whether FI of the supraspinatus (SS) and infraspinatus (IS), estimated using US was related to intramuscular fat fractions measured from magnetic resonance images (MRI). METHODS: Data from 12 healthy young adult participants were used for analysis. US images of the SS and IS were captured using multiple transducer placement techniques from which echogenicity of the muscle region was quantified. Shoulder MRI were captured from which SS and IS were manually segmented and intramuscular fat fractions calculated. Six upper limb strength exertions were performed, resisted by a hand dynamometer. RESULTS: IS and SS echogenicity explained a significant amount of variance in MRI fat fractions for certain body positions and transducer techniques. Echogenicity agreement was higher for IS than SS. Significant relationships were identified between strength exertions and both echogenicity and MRI muscle volume, but not MRI fat fraction. CONCLUSIONS: This research provides preliminary evidence showing that quantitative-based US methods can be used to estimate MRI calculated fat fractions for the rotator cuff.

Association between muscle quality and nutritional status among community-dwelling older adults: A cross-sectional study.

Background: Decline in muscle quality is associated with poorer health in community-dwelling older adults. Although there is evidence that malnutrition is associated with the decline of muscle quality in older adults, few analyses have considered important factors related to muscle quality. Aim: The purpose of this study was to determine the relationship between muscle quality and nutritional status in community-dwelling older adults, taking into account muscle mass, muscle strength, and amount of physical activity. Methods: This was a cross-sectional study. Data were obtained from a health checkup program in Japan. Participants were older adults aged ≥65 years living in the community who participated in the health checkup program. The data collected were echo intensity, scores on the Global Leadership Initiative on Malnutrition criteria, skeletal muscle mass, grip strength, physical activity level, and demographic data. Multiple regression analysis was used to examine the association between muscle quality and nutritional status. Results: Data were analyzed for 50 participants (mean age 77.62 years, standard deviation 6.16 years, 78.0% women). Multiple regression analysis showed that nutritional status affected muscle quality even when various factors were taken into account (B = 6.95, ß = 0.31, p = 0.04, 95% confidence interval: 0.01-0.62). Conclusion: The observed association suggests that providing nutritional support for older adults living in the community may be a useful strategy to maintain muscle quality.

Association of mid-thigh quadriceps muscle quality with postoperative outcomes in patients with hip osteoarthritis undergoing total hip arthroplasty: a retrospective cohort study.

PURPOSE: Muscle quality is more important than muscle mass for assessing physical function. Computed tomography (CT) is used to evaluate intramuscular fatty infiltration. The mid-thigh quadriceps CT attenuation values (CTV) expressed in Hounsfield units (HU) negatively correlate with physical function. Patients with hip osteoarthritis (HOA) have lower extremity muscle atrophy, including decreased cross-sectional area (CSA), CTV, and muscle strength. Using preoperative CT images, we investigated the association between mid-thigh quadriceps CSA, CTV, and postoperative outcomes in patients with HOA. METHODS: This study included 62 patients who had unilateral HOA (62 hips) and underwent total hip arthroplasty (THA). We investigated the association between preoperative and postoperative Japanese Orthopaedic Association (JOA) hip scores, 12-item Short Form survey (SF-12), mid-thigh quadriceps CSA, and CTV. RESULTS: The mean age was 64.7 ± 10.1 years, with 15 men (24.2%), and the mean body mass index was 24.3 ± 4.3 kg/m2. Secondary HOA was present in 79.0% of patients. The mean CSA and CTV of the mid-thigh quadriceps on the operative side were 38.8 ± 9.8 cm2 and 40.3 ± 7.8 HU, respectively. Multiple regression analyses adjusted for age and sex showed that preoperative mid-thigh quadriceps CSA was not associated with preoperative and postoperative JOA hip scores or SF-12. The preoperative mid-thigh quadriceps CTV was associated with the postoperative JOA hip score in the gait ability domain and SF-12 in the physical component summary domain. CONCLUSION: Preoperative muscle quality is associated with postoperative outcomes in patients who have HOA regardless of age and sex.

Myosteatosis, but not Sarcopenia, Predisposes NAFLD Subjects to Early Steatohepatitis and Fibrosis Progression.

BACKGROUND & AIMS: Sarcopenia and myosteatosis are associated with advanced nonalcoholic fatty liver disease (NAFLD). However, muscle alterations in early stage NAFLD remain unclear. METHODS: Patients with nonalcoholic fatty liver (NAFL) or early nonalcoholic steatohepatitis (NASH) without significant fibrosis were selected from a prospective biopsy-proven NAFLD cohort (N = 338). The skeletal muscle index and mean muscle attenuation (MA) were measured using abdominal fat computed tomography at the third lumbar vertebra level. Severe myosteatosis was defined as the lowest quartile of sex-stratified MA values. RESULTS: Patients with early NASH (n = 87) had lower MA (45.61 ± 6.45 vs 47.48 ± 5.85 HU; P = .028) than patients with NAFL (n = 251) but a similar skeletal muscle index. Patients with more severe lobular inflammation and hepatocellular ballooning had lower MA (P = .003 and P = .041, respectively). The severe myosteatosis prevalence was higher in early NASH than in NAFL (33.3% vs 21.1%; P = .029). Patients with severe myosteatosis were more likely to have early NASH in multivariable analysis adjusted for age, sex, and metabolic factors (odds ratio, 2.45; 95% confidence interval (CI), 1.24-4.86), which was maintained after adjustment for visceral fat amount (odds ratio, 2.44; 95% CI, 1.22-4.89). During a median 29-month follow-up, 170 patients underwent repeated transient elastography. Fibrosis progression-an increase in liver stiffness measurement >2 kPa or second liver stiffness measurement ≥7 kPa-was found in 28 and 31 individuals. Severe myosteatosis was significantly associated with fibrosis progression after adjustment for various confounders (hazard ratio, 2.49; 95% CI, 1.15-5.40 and hazard ratio, 2.09; 95% CI, 1.01-4.34 for different fibrosis progression definitions). CONCLUSIONS: Severe myosteatosis is significantly associated with early NASH and fibrosis progression in early stage NAFLD.

Computed tomography derived cervical fat-free muscle fraction as an imaging-based outcome marker in patients with acute ischemic stroke: a pilot study.

BACKGROUND: Outcome assessment in stroke patients is essential for evidence-based stroke care planning. Computed tomography (CT) is the mainstay of diagnosis in acute stroke. This study aimed to investigate whether CT-derived cervical fat-free muscle fraction (FFMF) as a biomarker of muscle quality is associated with outcome parameters after acute ischemic stroke. METHODS: In this retrospective study, 66 patients (mean age: 76 ± 13 years, 30 female) with acute ischemic stroke in the anterior circulation who underwent CT, including CT-angiography, and endovascular mechanical thrombectomy of the middle cerebral artery between August 2016 and January 2020 were identified. Based on densitometric thresholds, cervical paraspinal muscles covered on CT-angiography were separated into areas of fatty and lean muscle and FFMF was calculated. The study cohort was binarized based on median FFMF (cutoff value: < 71.6%) to compare clinical variables and outcome data between two groups. Unpaired t test and Mann-Whitney U test were used for statistical analysis. RESULTS: National Institute of Health Stroke Scale (NIHSS) (12.2 ± 4.4 vs. 13.6 ± 4.5, P = 0.297) and modified Rankin scale (mRS) (4.3 ± 0.9 vs. 4.4 ± 0.9, P = 0.475) at admission, and pre-stroke mRS (1 ± 1.3 vs. 0.9 ± 1.4, P = 0.489) were similar between groups with high and low FFMF. NIHSS and mRS at discharge were significantly better in patients with high FFMF compared to patients with low FFMF (NIHSS: 4.5 ± 4.4 vs. 9.5 ± 6.7; P = 0.004 and mRS: 2.9 ± 2.1 vs.3.9 ± 1.8; P = 0.049). 90-day mRS was significantly better in patients with high FFMF compared to patients with low FFMF (3.3 ± 2.2 vs. 4.3 ± 1.9, P = 0.045). CONCLUSION: Cervical FFMF obtained from routine clinical CT might be a new imaging-based muscle quality biomarker for outcome prediction in stroke patients.

Association of vastus lateralis diffusion properties with in vivo quadriceps contractile function in premenopausal women.

BACKGROUND: Diffusion tensor imaging (DTI) parameters correlate with muscle fiber composition, but it is unclear how these relate to in vivo contractile function. PURPOSE: To determine the relationship between DTI parameters of the vastus lateralis (VL) and in vivo knee extensor contractile. METHODS: Thirteen healthy, premenopausal women underwent magnetic resonance imaging of the mid-thigh to determine patellar tendon moment arm length and quadriceps cross-sectional area. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of the VL were determined using diffusion tensor imaging (DTI). Participants underwent an interpolated twitch (ITT) experiment before and after a fatiguing concentric-eccentric isokinetic knee extension (60°·s-1 ). During the ITT, supramaximal electrical stimuli were delivered to elicit twitch responses from the knee extensors before, during, and after a maximal voluntary isometric contraction (MVIC). Knee extensor-specific tension during twitch and MVIC were calculated from isometric torque data. Pearson's correlations were used to determine the relationship between muscle contractile properties and DTI parameters. RESULTS: MD and RD were moderately correlated with peak twitch force and rate of force development. FA and AD were moderately inversely related to percent change in MVIC following exercise. CONCLUSION: MD and RD are associated with in vivo quadriceps twitch properties but not voluntary strength, which may reflect the mechanical properties of constituent fiber types. FA and AD appear to relate to MVIC strength following fatiguing exercise.

Enhanced echo intensity in vastus medialis is associated with worsening of functional disabilities and symptoms in patients with knee osteoarthritis: a 3 years longitudinal study.

Patients with knee osteoarthritis (OA) experience muscle quality loss, and is characterized by the enhanced echo intensity (EI) of the vastus medialis (VM) muscles and a high extracellular water-to-intracellular water (ECW/ICW) ratio of the thigh. This study aimed to elucidate the association between muscle degeneration and the worsening of functional disabilities and symptoms in patients with KOA over 3 years duration. Thirty-three patients with KOA who completed follow-up over 3 years were included in the analysis. The knee scoring system (KSS) was used to evaluate the functional abilities and symptoms. Based on the 3 years change in KSS scores, patients were classified into progressive or non-progressive groups. Muscle thickness (MT) and EI of the VM were determined using ultrasonography. The ECW/ICW ratio was measured using segmental-bioelectrical impedance spectroscopy. Multivariable logistic regression analyses were conducted with the groups as the dependent variables and VM-MT, VM-EI, and ECW/ICW ratio at baseline as independent variables, including potential confounders. Thirteen (39.4%) patients showed progressive features. VM-EI at baseline was significantly associated with the progression of functional disabilities (adjusted odds ratio [OR] 1.24; 95% confidence interval [CI] 1.03 - 1.50) and symptoms (adjusted OR 1.13; 95% CI 1.01 - 1.25). Enhanced VM-EI was associated with the worsening of functional disabilities and symptoms in patients with KOA over a period of 3 years. Therefore, the assessment of VM-EI using ultrasonography is a useful indicator for predicting the future worsening of KOA.

Muscle Quality Index is inversely associated with psychosocial variables among Chilean adolescents.

A good muscle quality index (MQI) may have an inverse relationship with psychosocial variables of depression, anxiety, and stress in adolescents. Unfortunately, little scientific evidence has related MQI to psychosocial variables in this population. Therefore, this research aimed to determine the relationship between the MQI and psychosocial variables of depression, anxiety, and stress in Chilean adolescents. In this quantitative correlational design study, sixty adolescents participated voluntarily (mean ± standard deviation [SD]: age 15.11 ± 1.78 years). Anthropometric parameters, prehensile strength, MQI, and psychosocial variables were evaluated. The results showed that adolescents with high levels of MQI presented lower levels of depression (7.50 ± 6.06 vs. 10.97 ± 5.94), anxiety (5.64 ± 4.81 vs. 9.66 ± 5.12), and stress (6.79 ± 5.09 vs. 10 ± 5.58), in addition to reported lower abdominal obesity (WtHR, 0.47 ± 0.07 vs. 0.52 ± 0.07) than those with low levels of MQI. The group with high levels of MQI reported a higher prevalence of nonanxiety (81.3%, p = 0.031) and a lower prevalence of abdominal obesity (55.8%, p = 0.023). Likewise, a significant inverse association was evidenced between MQI and depression (ß; -6.18, 95% CI; -10.11: -2.25, p = 0.003), anxiety (ß; -6.61, 95% CI; -9.83: -3.39, p < 0.001) and stress (ß; -4.90, 95% CI; -8.49: -1.32 p = 0.008). In conclusion, the results suggest that high levels of MQI are associated with a higher prevalence of nonanxiety in adolescents and a significant inverse association between MQI and levels of depression, anxiety, and stress.

Association between relative muscle strength and hypertension in middle-aged and older Chinese adults.

BACKGROUND: The association between muscle defects and hypertension is well-established. However, the absence of pertinent and uncomplicated clinical indicators presents a challenge. Relative muscle strength (RMS) may offer a viable indicator. This study aimed to explore the association between RMS and hypertension. METHODS: A total of 12,720 individuals aged ≥ 45 years from the 2011 wave of the China Health and Retirement Longitudinal Study (CHARLS) were included. Grip strength was recorded and appendicular skeletal muscle mass (ASM) was estimated using a validated mathematical formula. The RMS was calculated as the ratio of grip strength to ASM. Hypertension was determined based on previous diagnosis, history of hypertension medication use, and current blood pressure. Logistic regression models were employed to investigate the relationship between RMS and hypertension. RESULTS: The prevalence of hypertension was 41.7% (5,307/12,720 patients). RMS was negatively correlated with hypertension with an OR (95% CI) of 0.68 (0.59-0.79) for males, 0.81 (0.73-0.90) for females, and 0.78 (0.72-0.85) for the entire population after adjusting for related covariates including age, education, marital history, smoking history, drinking history, diabetes, hyperlipidemia, and obesity. The trend test showed a linear association among males, females, or the entire population. Stratified analysis showed a consistent negative correlation between RMS and hypertension. CONCLUSIONS: Higher RMS is an independent protective factor against hypertension and efforts to promote RMS may be beneficial for the prevention and management of hypertension.

Muscle quality index and cardiovascular disease among US population-findings from NHANES 2011-2014.

BACKGROUND AND OBJECTIVE: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the United States. However, current evidence on the association between muscle quality and CVD is limited. This study investigates the potential association between the muscle quality index (MQI) and the prevalence of CVD and CVD-related mortality. METHODS: Participants were selected from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Data on mortality and causes of death were obtained from the National Death Index (NDI) records through December 31, 2019. Statistical analysis used in this study, including weighted multivariable linear and logistic regression, cox regression and Kaplan-Meier (K-M) analysis, to estimate the association between MQI and all-cause mortality as well as CVD mortality. In addition, subgroup analysis was used to estimate the association between MQI and CVD subtypes, such as heart attack, coronary heart disease, angina, congestive heart failure, and stroke. RESULTS: A total of 5,053 participants were included in the final analysis. Weighted multivariable linear regression models revealed that a lower MQI.total level was independently associated with an increased risk of CVD development in model 3, with t value =-3.48, 95%CI: (-0.24, -0.06), P = 0.002. During 5,053 person-years of 6.92 years of follow-up, there were 29 deaths from CVD. Still, the association between MQI.total and CVD mortality, as well as all-cause mortality did not reach statistical significance in the fully adjusted model (HR = 0.58, 95% CI: 0.21-1.62, P = 0.30; HR = 0.91, 95% CI:0.65,1.28, P = 0.59, respectively). Subgroup analysis confirmed that MQI.total was negatively associated with congestive heart failure (OR = 0.35, 95% CI = 0.18,0.68, P = 0.01). CONCLUSION: This study highlights the potential of MQI as a measure of muscle quality, its negative correlation with congestive heart failure (CHF). However, MQI was not very useful for predicting the health outcomes such as CVD and mortality. Therefore, more attention should be paid to the early recognition of muscle weakness progression in CHF. Further studies are needed to explore more effective indicator to evaluate the association between muscle quality and health outcomes.