Sarcopenia: burden and challenges for public health

Impact of imaging-diagnosed sarcopenia on outcomes in patients with biliary tract cancer after surgical resection: a systematic review and meta-analysis

BACKGROUND AND AIMS

Sarcopenia has been associated with poor prognosis in patients with malignant tumors. However, its impact on the outcomes of patients with biliary tract cancer (BTC) undergoing surgical resection remains unclear and warrants further review. This study aims to summarize the available evidence on this issue.

METHODS

A systematic search was conducted in PubMed, Embase, Web of Science, and the Cochrane Library for eligible studies up to March 10, 2024. We extracted data on overall survival (OS), recurrence free survival (RFS), and postoperative major complications from the included studies as the outcomes of interest. Following data synthesis and analysis, we assessed the heterogeneity and performed subgroup analyses. Additionally, the potential for publication bias was evaluated.

RESULTS

A total of 26 studies involving 4292 BTC patients were ultimately retrieved. The findings indicated that sarcopenia was significantly associated with reduced OS in BTC patients after surgery (adjusted HR: 2.03, 95% CI: 1.65-2.48, P < 0.001, I2 = 57.4%). Moreover, sarcopenia may also be linked to poorer RFS (adjusted HR: 2.15, 95% CI: 1.79-2.59, P < 0.001, I2 = 0%) and increased postoperative major complications (OR: 1.22, 95% CI 1.02-1.47, P = 0.033, I2 = 29.2%) as well. Notably, no significant publication bias was detected through funnel plots and Egger's tests.

CONCLUSION

Sarcopenia is associated with poorer OS in BTC patients following surgery. Additionally, it may serve as a prognostic indicator for poorer RFS and increased postoperative major complications. Further studies are warrant to standardize existing definitions and validate these findings.

Nutritional care in older adults: are we doing everything? An expert opinion review

Malnutrition is a prevalent, yet often underdiagnosed and undertreated, condition in older adults. It is characterized by weight loss and/or reduced muscle mass due to diminished caloric intake, inflammation, and/or disease burden. In return, malnutrition can lead to diminished skeletal muscle functionality and disability, among others. Malnutrition plays a crucial role in the pathogenesis of two prevalent geriatric syndromes, namely sarcopenia and frailty. The complex interplay between malnutrition, sarcopenia, and frailty significantly impacts the older population, leading to increased morbidity, mortality, hospitalization rates, quality-of-life, and healthcare costs. Given the prognostic significance of malnutrition in geriatric care, recent guidelines emphasized the role of nutritional support in vulnerable populations. A group of vulnerable populations to malnutrition, sarcopenia, and frailty are older patients with hip fractures, cancer patients, and those with sarcopenic dysphagia. This article highlights the importance of individualized nutritional assessment and treatment in the management of vulnerable populations such as older patients with hip fractures, cancer, and those suffering from sarcopenic dysphagia. It presents practical protocols and guidelines that can be instrumental in enhancing the nutritional care of these groups, thereby improving their overall health outcomes.

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

OBJECTIVE

Reliable identification of high-risk older adults who are likely to develop sarcopenia is essential to implement targeted preventive measures and follow-up. However, no sarcopenia prediction model is currently available for community use. Our objective was to develop and validate a risk prediction model for calculating the 1-year absolute risk of developing sarcopenia in an aging population.

METHODS

One prospective population-based cohort of non-sarcopenic individuals aged 60 years or older were used for the development of a sarcopenia risk prediction model and model validation. Sarcopenia was defined according to the 2019 Asian Working Group for Sarcopenia consensus. Stepwise logistic regression was used to identify risk factors for sarcopenia incidence within a 1-year follow-up. Model performance was evaluated using the area under the receiver operating characteristics curve (AUROC) and calibration plot, respectively.

RESULTS

The development cohort included 1042 older adults, among whom 87 participants developed sarcopenia during a 1-year follow-up. The PRE-SARC (PREdiction of SARCopenia Risk in community older adults) model can accurately predict the 1-year risk of sarcopenia by using 7 easily accessible community-based predictors. The PRE-SARC model performed well in predicting sarcopenia, with an AUROC of 87% (95% CI, 0.83-0.90) and good calibration. Internal validation showed minimal optimism, with an adjusted AUROC of 0.85. The prediction score was categorized into 4 risk groups: low (0%-10%), moderate (>10%-20%), high (>20%-40%), and very high (>40%). The PRE-SARC model has been incorporated into an online risk calculator, which is freely accessible for daily clinical applications (https://sarcopeniariskprediction.shinyapps.io/dynnomapp/).

CONCLUSIONS

In community-dwelling individuals, the PRE-SARC model can accurately predict 1-year sarcopenia incidence. This model serves as a readily available and free accessible tool to identify older adults at high risk of sarcopenia, thereby facilitating personalized early preventive approaches and optimizing the utilization of health care resources.

Effects of detraining on neuromuscular function and structural adaptations following once- or twice-weekly eccentric resistance training in older adults

BACKGROUND

Eccentric resistance training elicits greater preservation of training-induced muscular adaptations compared with other training modalities, however the detraining profiles of different training dosages remain unknown.

AIMS

To examine the detraining effects following once- or twice-weekly eccentric-specific resistance training in older adults.

METHODS

Twenty-one older adults (age = 70.5 ± 6.0 year) completed a 12-week detraining period following the 12-week eccentric training programmes with neuromuscular function and muscle structure assessed six (mid-detraining) and 12 (post-detraining) weeks following training cessation.

RESULTS

From post-training to post-detraining, no significant regression of the training-induced improvements (collapsed group data reported) occurred in power (0%), strength (eccentric = 0%, isometric = 39%), or explosive strength over numerous epochs (0-32%), resulting in values that remained significantly greater than at pre-training. However, significant regression in the improvements in muscle thickness (91%) and fascicle angle (100%) occurred, resulting in values that were not significantly greater than pre-training.

DISCUSSION

The limited regression in neuromuscular function following a 12-week detraining period has important implications for supporting eccentric exercise prescription in older adults who often face periods of inactivity. However, further work is required to develop an effective maintenance dosage strategy that preserves improvements in muscle structure.

CONCLUSIONS

Eccentric resistance training elicits improvements in the neuromuscular function of older adults, which are sustained for at least 12 weeks after eccentric training cessation.

High-density lipoprotein cholesterol level and risk of muscle strength decline and sarcopenia in older adults

BACKGROUND

Recent studies have demonstrated that very high high-density lipoprotein cholesterol (HDL-C) level was paradoxically linked with higher risk of cardiovascular mortality, all-cause mortality, and several age-related diseases. However, whether very high HDL-C level is associated with a higher risk of sarcopenia in older adults remains unclear. We aimed to investigate the association between HDL-C level and the risk of developing sarcopenia and low grip strength over time in older adults.

METHODS

Participants were from the ongoing China Health and Retirement Longitudinal Study (CHARLS), which includes a nationally representative sample of adults aged ≥45 years and was performed from 2011 to 2020 with follow-ups every two to three years. The current study included 4031 participants aged ≥60 years. Muscle health-related data were collected in waves 2011, 2013, and 2015. Based on HDL-C level at baseline, participants were categorized into five groups: <35 mg/dl, 35-40 mg/dl, 40-60 mg/dl, 60-70 mg/dl and >70 mg/dl. The main outcomes were incident sarcopenia and incident low grip strength over follow-up. Low grip strength and sarcopenia were defined according to the 2019 Consensus by the Asian Working Group for Sarcopenia. Cox proportional-hazard regression was performed to investigate the association between HDL-C level and the risk of developing sarcopenia and low grip strength in older adults.

RESULTS

The mean age of study sample was 67.3 (SD 6.1) years, and 49.6% were male. During an average 3.7-year follow-up, 409 (10.1%) participants developed sarcopenia and 771 (21.1%) developed low grip strength. Non-linear association was observed between HDL-C level and the hazard of developing sarcopenia and low grip strength. The multivariable model showed that compared to the reference group (40-60 mg/dl), older adults with very high HDL-C level (>70 mg/dl) had a significantly higher risk of developing sarcopenia (HR 1.69, 95% CI 1.28-2.23) and low grip strength (HR 1.23 95% CI 1.00-1.51). Stratified analyses by sex revealed similar association.

CONCLUSIONS

We present the first longitudinal evidence that very high HDL-C level was associated with a significantly higher risk of muscle strength decline and developing sarcopenia in older adults. It is essential to monitor the muscle health of older adults with very high HDL-C level in clinical practice.

Relationship between creatinine-cystatin C ratio and all-cause mortality in hospitalized patients with COVID-19: A prospective study in China

Background

This study was conducted to investigate whether baseline creatinine-cystatin C ratio is associated with all-cause mortality in adult Chinese patients hospitalized with coronavirus disease 2019.

Methods

This study included 933 patients with coronavirus disease 2019 who were admitted to The Affiliated Hospital of Guangdong Medical University between December 2022 and March 2023. All-cause mortality was determined by telephone follow-up after 28 days. Multivariate Cox proportional risk models were used to investigate the relationship between baseline creatinine-cystatin C ratio and all-cause mortality. Restricted cubic spline and two-piecewise Cox proportional hazards risk models were used to identify non-linear correlations.

Results

Of the 933 patients, 128 died during the 28 days follow-up. The restricted cubic spline analysis of hospitalized patients with coronavirus disease 2019 revealed an L-shaped association between baseline creatinine-cystatin C ratio and all-cause mortality, with a threshold creatinine-cystatin C ratio of ≤0.93 predicting all-cause mortality. Specifically, a baseline creatinine-cystatin C ratio below this threshold value was negatively correlated with mortality (hazard ratio 0.12, 95 % confidence interval 0.03-0.48), but a creatinine-cystatin C ratio >0.93 was not correlated with mortality (hazard ratio 1.29, 95 % confidence interval 0.65-2.55).

Conclusions

In Chinese adult patients hospitalized with coronavirus disease 2019, an L-shaped relationship was observed between the baseline creatinine-cystatin C ratio and all-cause mortality.

Performance of calf circumference in identifying sarcopenia in older patients with chronic low back pain: a retrospective cross-sectional study

BACKGROUND

Calf circumference is currently recommended as a case-finding marker for sarcopenia, but its usefulness has not been determined in chronic pain conditions. Therefore, the present study aimed to evaluate the predictive performance of calf circumference in diagnosing sarcopenia in older patients with chronic low back pain.

METHODS

Ambulatory adult patients aged ≥ 65 years with chronic low back pain were enrolled. A diagnosis of sarcopenia was established based on the criteria outlined by the Asian Working Group for Sarcopenia in 2019. Patient demographics, pain-related factors, clinical factors, and sarcopenia-related measurements were compared between non-sarcopenic and sarcopenic patients. Linear regression analysis was used to evaluate the correlation of calf circumference with muscle mass, strength, and physical performance. Also, a receiver operating characteristic curve analysis for calf circumference in predicting sarcopenia was conducted; and area under the curve (AUC) values, along with their corresponding 95% confidence intervals (CI), were calculated.

RESULTS

Data from 592 patients were included in the analysis. Eighty-five patients were diagnosed with sarcopenia (14.3%), 71 of whom had severe sarcopenia (11.9%). A higher prevalence of sarcopenia was observed in female patients (9.0% vs. 16.7%, p = 0.016). After adjusting for age, BMI, and comorbidities, calf circumference correlated positively with muscle mass but not with muscle strength and physical performance. The AUC values for sarcopenia were 0.754 (95% CI = 0.636-0.871, p = 0.001) in males and 0.721 (95% CI = 0.657-0.786, p < 0.001) in females. The cut-offs for calf circumference in predicting sarcopenia were 34 cm (sensitivity 67.1%, specificity 70.6%) in males, and 31 cm (sensitivity 82.5%, specificity 51.5%) in females.

CONCLUSIONS

Even though sex differences in its predictive value for sarcopenia should be considered, our findings suggest that calf circumference can be used as an indicator for predicting muscle mass and may serve as a potential marker for identifying sarcopenia in older patients with chronic low back pain.

Mitigating disuse-induced skeletal muscle atrophy in ageing: Resistance exercise as a critical countermeasure

The gradual deterioration of physiological systems with ageing makes it difficult to maintain skeletal muscle mass (sarcopenia), at least partly due to the presence of 'anabolic resistance', resulting in muscle loss. Sarcopenia can be transiently but markedly accelerated through periods of muscle disuse-induced (i.e., unloading) atrophy due to reduced physical activity, sickness, immobilisation or hospitalisation. Periods of disuse are detrimental to older adults' overall quality of life and substantially increase their risk of falls, physical and social dependence, and early mortality. Disuse events induce skeletal muscle atrophy through various mechanisms, including anabolic resistance, inflammation, disturbed proteostasis and mitochondrial dysfunction, all of which tip the scales in favour of a negative net protein balance and subsequent muscle loss. Concerningly, recovery from disuse atrophy is more difficult for older adults than their younger counterparts. Resistance training (RT) is a potent anabolic stimulus that can robustly stimulate muscle protein synthesis and mitigate muscle losses in older adults when implemented before, during and following unloading. RT may take the form of traditional weightlifting-focused RT, bodyweight training and lower- and higher-load RT. When combined with sufficient dietary protein, RT can accelerate older adults' recovery from a disuse event, mitigate frailty and improve mobility; however, few older adults regularly participate in RT. A feasible and practical approach to improving the accessibility and acceptability of RT is through the use of resistance bands. Moving forward, RT must be prescribed to older adults to mitigate the negative consequences of disuse atrophy.

The prevalence patterns and risk factor profiles of poor muscle health and its associated components in multiethnic older Asians: The PIONEER study

BACKGROUND

We aim to determine the multiethnic patterns of the prevalence and associated factors of poor muscle health and its associated components in older Chinese, Malays, and Indian Asian adults.

METHODS

We included 2199 participants (mean age ± SD: 72.9 ± 8.3 years; 54.3% female) from the baseline assessment of the Population Health and Eye Disease Profile in Elderly Singaporeans (PIONEER; 2017-2022) cohort study. Poor muscle health was defined as the presence of either low muscle mass (DEXA), or low muscle strength (handgrip strength), or low physical performance (gait speed). Its components include poor muscle function (low muscle strength and/or low physical performance without low muscle mass), pre-sarcopenia (low muscle mass only), and any sarcopenia (low muscle mass with low muscle strength and/or low physical performance). Sociodemographic, clinical, and lifestyle factors were assessed using biochemistry, clinical tests, and validated questionnaires. Regression models were utilized to evaluate the independent risk factors of poor muscle health and its components.

RESULTS

The national census-adjusted prevalence of poor muscle health (88%) was similar across the three ethnic groups. However, Chinese individuals had higher prevalence of pre-sarcopenia and any sarcopenia, and a lower prevalence of poor muscle function compared with Indians or Malays. We observed ethnic differences in modifiable risk factors (low physical activity, diabetes, osteoporosis, and obesity) of poor muscle health and its components. Although obesity was protective of pre-sarcopenia (RRR = 0.19, 95% CI: 0.11, 0.36) and any sarcopenia (RRR = 0.29, 95% CI: 0.18, 0.47) in the overall population and across ethnic groups, it was associated with 1.7 times (95% CI: 1.07, 2.67) the likelihood of poor muscle function in the entire population.

CONCLUSIONS

Almost 90% of community dwelling Singaporean aged ≥60 years have poor muscle health across the three ethnic groups with ethnic disparities in modifiable risk factors, highlighting an urgent need for community-wide targeted interventions to promote muscle health.

Association of dietary patterns with sarcopenia in adults aged 50 years and older

PURPOSE

Although numerous studies have investigated the impact of dietary factors on the prevention of decreased muscle mass and function, limited research has examined the relationship between dietary patterns and sarcopenia. This study aimed to assess the associations between dietary patterns, and sarcopenia, muscle strength, and mass in adults following a Mediterranean diet residing in southern Italian cities.

METHODS

This cross-sectional study utilized data from an existing database, comprising 528 individuals aged 50 years or older who underwent health-screening tests at the Clinical Nutrition Unit of the "R.Dulbecco" University Hospital. Strength was assessed through handgrip strength, and appendicular skeletal muscle mass was estimated using bioelectrical impedance analysis. Dietary intake information was collected through a food frequency questionnaire linked to the MetaDieta 3.0.1 nutrient composition database. Principal Component Analysis, a statistical technique identifying underlying relationships among different nutrients, was employed to determine dietary patterns. Multinomial logistic regression analysis was conducted to estimate the odds ratio for sarcopenia or low handgrip strength in relation to the lowest tertile of dietary pattern adherence compared to the highest adherence.

RESULTS

The participants had a mean age of 61 ± 8 years. Four dietary patterns were identified, with only the Western and Mediterranean patterns showing correlations with handgrip strength and appendicular skeletal muscle mass. However, only the Mediterranean pattern exhibited a correlation with sarcopenia (r =  - 0.17, p = 0.02). The highest tertile of adherence to the Mediterranean dietary pattern demonstrated significantly higher handgrip strength compared to the lowest tertile (III Tertile: 28.3 ± 0.5 kg vs I Tertile: 26.3 ± 0.5 kg; p = 0.01). Furthermore, even after adjustment, the highest tertile of adherence to the Mediterranean pattern showed a significantly lower prevalence of sarcopenia than the lowest adherence tertile (4% vs 16%, p = 0.04). The lowest adherence to the Mediterranean dietary pattern was associated with increased odds of having low muscle strength (OR = 2.38; p = 0.03; 95%CI = 1.05-5.37) and sarcopenia (OR = 9.69; p = 0.0295; %CI = 1.41-66.29).

CONCLUSION

A high adherence to the Mediterranean dietary pattern, characterized by increased consumption of legumes, cereals, fruits, vegetables, and limited amounts of meat, fish, and eggs, is positively associated with handgrip strength and appendicular skeletal muscle mass. The highest adherence to this dietary model is associated with the lowest odds of low muscle strength and sarcopenia. Despite the changes brought about by urbanization in southern Italy compared to the past, our findings continue to affirm the superior benefits of the Mediterranean diet in postponing the onset of frailty among older adults when compared to other dietary patterns that are rich in animal foods.

Skeletal muscle estimation: A review of techniques and their applications

Quantifying skeletal muscle size is necessary to identify those at risk for conditions that increase frailty, morbidity, and mortality, as well as decrease quality of life. Although muscle strength, muscle quality, and physical performance have been suggested as important assessments in the screening, prevention, and management of sarcopenic and cachexic individuals, skeletal muscle size is still a critical objective marker. Several techniques exist for estimating skeletal muscle size; however, each technique presents with unique characteristics regarding simplicity/complexity, cost, radiation dose, accessibility, and portability that are important factors for assessors to consider before applying these modalities in practice. This narrative review presents a discussion centred on the theory and applications of current non-invasive techniques for estimating skeletal muscle size in diverse populations. Common instruments for skeletal muscle assessment include imaging techniques such as computed tomography, magnetic resonance imaging, peripheral quantitative computed tomography, dual-energy X-ray absorptiometry, and Brightness-mode ultrasound, and non-imaging techniques like bioelectrical impedance analysis and anthropometry. Skeletal muscle size can be acquired from these methods using whole-body and/or regional assessments, as well as prediction equations. Notable concerns when conducting assessments include the absence of standardised image acquisition/processing protocols and the variation in cut-off thresholds used to define low skeletal muscle size by clinicians and researchers, which could affect the accuracy and prevalence of diagnoses. Given the importance of evaluating skeletal muscle size, it is imperative practitioners are informed of each technique and their respective strengths and weaknesses.

CT imaging-derived phenotypes for abdominal muscle and their association with age and sex in a medical biobank

The study of muscle mass as an imaging-derived phenotype (IDP) may yield new insights into determining the normal and pathologic variations in muscle mass in the population. This can be done by determining 3D abdominal muscle mass from 12 distinct abdominal muscle regions and groups using computed tomography (CT) in a racially diverse medical biobank. To develop a fully automatic technique for assessment of CT abdominal muscle IDPs and preliminarily determine abdominal muscle IDP variations with age and sex in a clinically and racially diverse medical biobank. This retrospective study was conducted using the Penn Medicine BioBank (PMBB), a research protocol that recruits adult participants during outpatient visits at hospitals in the Penn Medicine network. We developed a deep residual U-Net (ResUNet) to segment 12 abdominal muscle groups including the left and right psoas, quadratus lumborum, erector spinae, gluteus medius, rectus abdominis, and lateral abdominals. 110 CT studies were randomly selected for training, validation, and testing. 44 of the 110 CT studies were selected to enrich the dataset with representative cases of intra-abdominal and abdominal wall pathology. The studies were divided into non-overlapping training, validation and testing sets. Model performance was evaluated using the Sørensen-Dice coefficient. Volumes of individual muscle groups were plotted to distribution curves. To investigate associations between muscle IDPs, age, and sex, deep learning model segmentations were performed on a larger abdominal CT dataset from PMBB consisting of 295 studies. Multivariable models were used to determine relationships between muscle mass, age and sex. The model's performance (Dice scores) on the test data was the following: psoas: 0.85 ± 0.12, quadratus lumborum: 0.72 ± 0.14, erector spinae: 0.92 ± 0.07, gluteus medius: 0.90 ± 0.08, rectus abdominis: 0.85 ± 0.08, lateral abdominals: 0.85 ± 0.09. The average Dice score across all muscle groups was 0.86 ± 0.11. Average total muscle mass for females was 2041 ± 560.7 g with a high of 2256 ± 560.1 g (41-50 year old cohort) and a change of - 0.96 g/year, declining to an average mass of 1579 ± 408.8 g (81-100 year old cohort). Average total muscle mass for males was 3086 ± 769.1 g with a high of 3385 ± 819.3 g (51-60 year old cohort) and a change of - 1.73 g/year, declining to an average mass of 2629 ± 536.7 g (81-100 year old cohort). Quadratus lumborum was most highly correlated with age for both sexes (correlation coefficient of - 0.5). Gluteus medius mass in females was positively correlated with age with a coefficient of 0.22. These preliminary findings show that our CNN can automate detailed abdominal muscle volume measurement. Unlike prior efforts, this technique provides 3D muscle segmentations of individual muscles. This technique will dramatically impact sarcopenia diagnosis and research, elucidating its clinical and public health implications. Our results suggest a peak age range for muscle mass and an expected rate of decline, both of which vary between genders. Future goals are to investigate genetic variants for sarcopenia and malnutrition, while describing genotype-phenotype associations of muscle mass in healthy humans using imaging-derived phenotypes. It is feasible to obtain 3D abdominal muscle IDPs with high accuracy from patients in a medical biobank using fully automated machine learning methods. Abdominal muscle IDPs showed significant variations in lean mass by age and sex. In the future, this tool can be leveraged to perform a genome-wide association study across the medical biobank and determine genetic variants associated with early or accelerated muscle wasting.

Prevalence and predictive value of sarcopenia in hospitalized patients with ischemic colitis

Ischemic colitis (IC) and sarcopenia are associated with aging and multiple comorbidities. We aimed to investigate the prevalence and predictive role of sarcopenia in patients with IC. We retrospectively analyzed 225 hospitalized patients (median age, 72 years; women, 67.1%; severe IC, 34.2%) who were diagnosed with IC between January 2007 and February 2022. Sarcopenia was defined as the skeletal muscle index at the third lumbar vertebra determined by computed tomography. It was present in 49.3% (n = 111) of the patients and was significantly associated with severe IC compared to those without sarcopenia (48.6% vs. 20.2%, P < 0.001). Sarcopenia was associated with extended hospitalization (median: 8 vs. 6 days, P < 0.001) and fasting periods (4 vs. 3 days, P = 0.004), as well as prolonged antibiotic use (9 vs. 7 days, P = 0.039). Sarcopenia was linked to a higher risk of surgery or mortality (9.0% vs. 0%, P = 0.001) and independently predicted this outcome (odds ratio [OR], 11.17; 95% confidence interval [CI], 1.24‒1467.65, P = 0.027). It was prevalent among hospitalized patients with IC, potentially indicating severe IC and a worse prognosis. This underscores the importance of meticulous monitoring, immediate medical intervention, and timely surgical consideration.

Telomere Length is Associated with the Prevalence, Persistence, and Incidence of Sarcopenia

BACKGROUND

Telomere length (TL) shortening has been identified as a marker of aging and associated with adverse health outcomes, but evidence of its association with sarcopenia is inconclusive.

AIMS

Estimate the cross-sectional and prospective associations between TL and sarcopenia.

METHODS

We used data from Waves 3 and 4 (2017, 2021) of the Study on Global Aging and Adult Health in Mexico (SAGE-Mexico). The cross-sectional sample consisted of 1,738 adults aged 50 and older, and the longitudinal sample consisted of 1,437. Relative TL was determined by real-time quantitative polymerase chain reaction (qPCR) on DNA extracted from saliva samples and quantified as the telomere/single-copy gene (T/S) ratio. Sarcopenia was defined according to the European Working Group on Sarcopenia in Older People (EWGSOP2).

RESULTS

The mean salivary TL was 1.50 T/S units (95% CI: 1.49-1.52). The baseline prevalence of sarcopenia was 13.3% (95% CI: 9.8-16.8%). The incidence and persistence of sarcopenia were 6.8% (95% CI: 5.0-9.5%) and 7.0% (95% CI: 5.1-9.6%), respectively. The results showed that a one standard deviation decrease in TL was cross-sectionally associated with higher odds of sarcopenia (OR = 1.31; 95% CI: 1.03-1.67) and prospectively with a higher incidence (RRR = 1.55; 95% CI: 1.06-2.25) and persistence (RRR = 1.50; 95% CI: 1.01-2.24) of sarcopenia.

CONCLUSIONS

Older adults with shorter TL had higher rates of incident and persistent sarcopenia. Implementation of interventions to delay the decline of TL in older adults is warranted. Further translational studies are needed to elucidate the effects of exercise or diet on DNA repair in the telomeric region and their associations with sarcopenia.

Implications of the diagnosis of locomotive syndrome stage 3 for long-term care

Objectives

Locomotive syndrome stage 3 (LS3), which has been established recently, may imply a greater need for care than LS stage 0 (LS0), LS stage 1 (LS1), and LS stage 2 (LS2). The relationship between LS3 and long-term care in Japan is unclear. Therefore, this study aimed to examine this relationship.

Methods

A total of 531 patients (314 women and 217 men; mean age, 75 years) who were not classified as requiring long-term care and underwent musculoskeletal examinations in 2012 were grouped according to their LS stage. Group L comprised patients with LS3 and Group N comprised those with LS0, LS1, and LS2. We compared these groups according to their epidemiology results and long-term care requirements from 2013 to 2018.

Results

Fifty-nine patients (11.1%) were diagnosed with LS3. Group L comprised more patients (50.8%) who required long-term care than Group N (17.8%) (P < 0.001). Group L also comprised more patients with vertebral fractures and knee osteoarthritis than Group N (33.9% vs 19.5% [P = 0.011] and 78% vs 56.4% [P < 0.001], respectively). A Cox proportional hazards model and Kaplan-Meier analysis revealed a significant difference in the need for nursing care between Groups L and N (log-rank test, P < 0.001; hazard ratio, 2.236; 95% confidence interval, 1.451-3.447).

Conclusions

Between 2012 and 2018, 50% of patients with LS3 required nursing care. Therefore, LS3 is a high-risk condition that necessitates interventions. Approaches to vertebral fractures and osteoarthritis of the knee could be key.

Machine-learning classifier models for predicting sarcopenia in the elderly based on physical factors

AIM

As the size of the elderly population gradually increases, musculoskeletal disorders, such as sarcopenia, are increasing. Diagnostic techniques such as X-rays, computed tomography, and magnetic resonance imaging are used to predict and diagnose sarcopenia, and methods using machine learning are gradually increasing. This study aimed to create a model that can predict sarcopenia using physical characteristics and activity-related variables without medical diagnostic equipment, such as imaging equipment, for the elderly aged 60 years or older.

METHODS

A sarcopenia prediction model was constructed using public data obtained from the Korea National Health and Nutrition Examination Survey. Models were built using Logistic Regression, Support Vector Machine (SVM), XGBoost, LightGBM, RandomForest, and Multi-layer Perceptron Neural Network (MLP) algorithms, and the feature importance of the models trained with the algorithms, except for SVM and MLP, was analyzed.

RESULTS

The sarcopenia prediction model built with the LightGBM algorithm achieved the highest test accuracy, of 0.848. In constructing the LightGBM model, physical characteristic variables such as body mass index, weight, and waist circumference showed high importance, and activity-related variables were also used in constructing the model.

CONCLUSIONS

The sarcopenia prediction model, which consisted of only physical characteristics and activity-related factors, showed excellent performance. This model has the potential to assist in the early detection of sarcopenia in the elderly, especially in communities with limited access to medical resources or facilities. Geriatr Gerontol Int 2024; 24: 595-602.

Sarcopenia in peripheral arterial disease: Establishing and validating a predictive nomogram based on clinical and computed tomography angiography indicators

Purpose

To establish, validate, and clinically evaluate a nomogram for predicting the risk of sarcopenia in patients with peripheral arterial disease (PAD) based on clinical and lower extremity computed tomography angiography (LE-CTA) imaging characteristics.

Methods

Clinical data and CTA imaging features from 281 PAD patients treated between January 1, 2019, and May 1, 2023, at two hospitals were retrospectively analyzed using binary logistic regression to identify the independent risk factors for sarcopenia. These identified risk factors were used to develop a predictive nomogram. The nomogram's effectiveness was assessed through various metrics, including the receiver operating characteristic (ROC) curve, area under the curve (AUC), concordance index (C-index), Hosmer-Lemeshow (HL) test, and calibration curve. Its clinical utility was demonstrated using decision curve analysis (DCA).

Results

Several key independent risk factors for sarcopenia in PAD patients were identified, namely age, body mass index (BMI), history of coronary heart disease (CHD), and white blood cell (WBC) count, as well as the severity of luminal stenosis (P < 0.05). The discriminative ability of the nomogram was supported by the C-index and an AUC of 0.810 (95% confidence interval: 0.757-0.862). A robust concordance between predicted and observed outcomes was reflected by the calibration curve. The HL test further affirmed the model's calibration with a P-value of 0.40. The DCA curve validated the nomogram's favorable clinical utility. Lastly, the model underwent internal validation.

Conclusions

A simple nomogram based on five independent factors, namely age, BMI, history of CHD, WBC count, and the severity of luminal stenosis, was developed to assist clinicians in estimating sarcopenia risk among PAD patients. This tool boasts impressive predictive capabilities and broad utility, significantly aiding clinicians in identifying high-risk individuals and enhancing the prognosis of PAD patients.

Prevalence and impact of sarcopenia in individuals with heart failure with reduced ejection fraction (the SARC-HF study): A prospective observational study protocol

Sarcopenia, a clinical syndrome primarily associated with reduced muscle mass in the elderly, has a negative impact on quality of life and survival. It can occur secondarily to other diseases such as heart failure (HF), a complex clinical syndrome with high morbidity and mortality. The simultaneous occurrence of these two conditions can worsen the prognosis of their carriers, especially in the most severe cases of HF, as in patients with reduced left ventricular ejection fraction (LVEF). However, due to the heterogeneous diagnostic criteria for sarcopenia, estimates of its prevalence present a wide variation, leading to new criteria having been recently proposed for its diagnosis, emphasizing muscle strength and function rather than skeletal muscle mass. The primary objective of this study is to evaluate the prevalence of sarcopenia and/or dynapenia in individuals with HF with reduced LVEF according to the most recent criteria, and compare the gene and protein expression of those patients with and without sarcopenia. The secondary objectives are to evaluate the association of sarcopenia and/or dynapenia with the risk of clinical events and death, quality of life, cardiorespiratory capacity, ventilatory efficiency, and respiratory muscle strength. The participants will answer questionnaires to evaluate sarcopenia and quality of life, and will undergo the following tests: handgrip strength, gait speed, dual-energy X-ray absorptiometry, respiratory muscle strength, cardiopulmonary exercise, as well as genomic and proteomic analysis, and dosage of N-terminal pro-B-type natriuretic peptide and growth differentiation factor-15. An association between sarcopenia and/or dynapenia with unfavorable clinical evolution is expected to be found, in addition to reduced quality of life, cardiorespiratory capacity, ventilatory efficiency, and respiratory muscle strength.

The association between healthy beverage index and sarcopenia in Iranian older adults: a case-control study

BACKGROUND

Sarcopenia is a progressive disease with age-related loss of skeletal muscle mass, strength, and function. No study has investigated the association between healthy beverage index (HBI) and sarcopenia in older adults. Therefore, the present study aimed to investigate the association between HBI and sarcopenia in Iranian older adults.

METHODS

In the present case-control study, 80 sarcopenic and 80 non-sarcopenic participants matched in sex were included. Body composition was measured using bioelectrical impedance analysis. Handgrip strength (HGS), skeletal muscle mass index (SMI), and gait speed were utilized to confirm sarcopenia. Also, a food frequency questionnaire was used to evaluate food intake. HBI score was calculated based on ten sub-components of the total beverages. Moreover, logistic regression was applied to assess the association between HBI and sarcopenia.

RESULTS

In the crude model, we observed no significant association between HBI and the odds of sarcopenia. Still, after adjusting the confounders, the odds of developing sarcopenia decreased significantly in the second and last tertiles (T) (T2- odds ratio (OR) = 0.04, 95% confidence interval (CI): 0.01-0.25 and T3- OR = 0.10, 95% CI: 0.01-0.60).

CONCLUSIONS

Our findings indicated that HBI is inversely related to the chance of sarcopenia. Therefore, to reduce the odds of sarcopenia, it is recommended to consume healthy drinks such as fruit juices and milk.

Sarcopenia in systemic sclerosis: prevalence and impact-a systematic review and meta-analysis

OBJECTIVE

This review aims to provide an estimate of sarcopenia prevalence and its impact on clinical characteristics in patients with systemic sclerosis (SSc).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Embase, Medline, Web of Science and the Cochrane Central Register of Controlled Trials were systemically searched from inception to 24 May 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included observational studies that reported the prevalence of sarcopenia in patients with SSc.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently performed study selection and data extraction using standardised methods. Risk of bias was assessed using the Agency for Healthcare Research and Quality Scale and the Newcastle-Ottawa Scale. Meta-analysis was conducted using random effects models.

RESULTS

A total of 4583 articles were screened and 9 studies with data from 815 patients were included in the analysis (8 cross-sectional studies and 1 retrospective cohort study). The overall prevalence of sarcopenia in patients with SSc was 22% (95% CI 17% to 28%). Patients with SSc with sarcopenia had a poorer quality of life (mean difference -12.02; 95% CI -19.11 to -4.93) and higher C reactive protein (CRP) levels (standardised mean difference 0.67; 95% CI 0.35 to 1.00).

CONCLUSIONS

Sarcopenia is common in patients with SSc. Patients with SSc with sarcopenia had a worse quality of life and higher CRP levels, based on our findings. Given the detrimental impact of sarcopenia on quality of life, future efforts aimed at early identification of sarcopenia in the clinical assessment of patients with SSc may have significance.

PROSPERO REGISTRATION NUMBER

CRD42022368326.

The geriatric nutrition risk index is longitudinally associated with incident Sarcopenia: evidence from a 5-year prospective cohort

BACKGROUND

Previous studies investigating the association between the geriatric nutrition risk index (GNRI) and sarcopenia either lacked longitudinal evidence or narrowly focused on specific populations.

AIMS

We aimed to reveal longitudinal associations of GNRI with sarcopenia risk in community-dwelling Chinese. We also investigated interaction effects of potential factors on such associations.

METHODS

We included participants aged ≥ 50 years with sufficient data from the WCHAT study who did not have sarcopenia at baseline and completed sarcopenia assessment during follow-up. GNRI was calculated according to the formula based on serum albumin, height and weight. Sarcopenia was diagnosed according to the 2019 AWGS consensus. Longitudinal associations between GNRI and sarcopenia were estimated by logistic regression with GNRI as either a continuous or categorical variable by tertiles, using generalized estimating equations (GEE) as sensitivity analyses. Subgroup analyses by potential covariates were conducted to detect interaction effects.

RESULTS

A total of 1907 participants without baseline sarcopenia were finally included, of whom 327 (17.1%) developed incident sarcopenia during 5-year follow-up. After controlling for confounders, sarcopenia risk decreased with each one standard deviation increase in GNRI (ORadjusted=0.36, 95% CI 0.31-0.43), and it also decreased successively from the lowest (< 111.2) through middle (111.2-117.7) to the highest (≥ 117.8) tertile of the GNRI level (P for trend < 0.001). Similar results were yielded by GEE. Such associations generally remained robust across subgroups with distinct characteristics, while significant differences were observed between different age groups (≥ 65 vs. <65 years) (interaction P-value < 0.05).

CONCLUSION

GNRI is longitudinally associated with sarcopenia risk with possibly age-specific differences in association magnitude, which holds implications for policymakers to conduct population-based risk assessment.

Size or Strength? how components of muscle relate to behavioral and neuroelectric measures of executive function independent of aerobic fitness

While previous research has linked cognitive function with resistance exercise, the nuanced links between muscle strength, mass, and neuroelectric function are less understood. Therefore, this study investigated the association of muscle strength and mass with inhibitory control (IC), working memory (WM), and related neuroelectric activity. A total of 123 18-50-year-old adults completed maximal aerobic capacity and strength tests, a body composition scan, and IC and WM tasks while the N2 and P3 components of event-related potentials were recorded. Bivariate correlations revealed aerobic fitness, strength, and mass were associated with behavioral and neuroelectric outcomes. After accounting for age, sex, and aerobic fitness, strength was associated with intra-individual response time variability, accuracy, and P3 latency during WM. Muscle mass was associated with N2 latency during IC. While relationships with behavioral outcomes did not persist after controlling for the opposite muscle outcome, greater strength and mass were related to shorter P3 latency during WM and shorter N2 latency during IC, respectively. These results provide initial evidence that muscle outcomes are associated with executive function and neuroelectric processing speed, suggesting distinct contributions of strength and mass to cognition. This work highlights the significance of maintaining muscle strength and mass alongside aerobic fitness for optimal cognitive health.

Muscle Reference Values From Thoracic and Abdominal CT for Sarcopenia Assessment: The Framingham Heart Study

BACKGROUND

Loss of muscle mass is a known feature of sarcopenia and predicts poor clinical outcomes. Although muscle metrics can be derived from routine computed tomography (CT) images, sex-specific reference values at multiple vertebral levels over a wide age range are lacking.

OBJECTIVE

The aim of this study was to provide reference values for skeletal muscle mass and attenuation on thoracic and abdominal CT scans in the community-based Framingham Heart Study cohort to aid in the identification of sarcopenia.

MATERIALS AND METHODS

This secondary analysis of a prospective trial describes muscle metrics by age and sex for participants from the Framingham Heart Study without prior history of cancer who underwent at least 1 CT scan between 2002 and 2011. Using 2 previously validated machine learning algorithms followed by human quality assurance, skeletal muscle was analyzed on a single axial CT image per level at the 5th, 8th, 10th thoracic, and 3rd lumbar vertebral body (T5, T8, T10, L3). Cross-sectional muscle area (cm 2 ), mean skeletal muscle radioattenuation (SMRA, in Hounsfield units), skeletal muscle index (SMI, in cm 2 /m 2 ), and skeletal muscle gauge (SMRA·SMI) were calculated. Measurements were summarized by age group (<45, 45-54, 55-64, 65-74, ≥75 years), sex, and vertebral level. Models enabling the calculation of age-, sex-, and vertebral-level-specific reference values were created and embedded into an open access online Web application.

RESULTS

The cohort consisted of 3804 participants (1917 [50.4%] males; mean age, 55.6 ± 11.8 years; range, 33-92 years) and 7162 CT scans. Muscle metrics qualitatively decreased with increasing age and female sex.

CONCLUSIONS

This study established age- and sex-specific reference values for CT-based muscle metrics at thoracic and lumbar vertebral levels. These values may be used in future research investigating the role of muscle mass and attenuation in health and disease, and to identify sarcopenia.

Sarcopenia Does Not Impact the Outcome of Patients with Multiple Myeloma Consolidated with Autologous Hematopoietic Stem Cell Transplantation

INTRODUCTION

Sarcopenia has been associated with chronic diseases and cancer. The aim of this study was to evaluate sarcopenia in multiple myeloma patients undergoing autologous stem cell transplantation.

METHODS

In 68 eligible patients, measurement of skeletal muscle area (cm2) on computed tomography scans at the level of the L3 vertebra (L3 SMI) was performed.

RESULTS

37 (54%) patients were categorized as sarcopenic: 26 males with L3 SMI values <52.4 cm2/m2, and 11 women with L3 SMI values <38.9 cm2/m2. The majority of sarcopenic patients included were older than 60 years (69%, p = 0.0005), with BMI <25 (75%; p = 0.0000). A significant association was found between sarcopenia and Sorror score value >1 (p = 0.02).

CONCLUSIONS

The Kaplan-Meier curve showed a median OS of 73.5 months for non-sarcopenic patients versus 86.5 months for sarcopenic patients, suggesting that sarcopenia is not an independent prognostic factor in this cohort of patients. Further prospective studies are needed to confirm these data.

Possible sarcopenia and risk of chronic kidney disease: a four-year follow-up study and Mendelian randomization analysis

INTRODUCTION

Chronic kidney disease (CKD) is a common risk factor for sarcopenia. However, whether sarcopenia increases the risk of CKD remains unclear. To investigate the longitudinal and causal associations between possible sarcopenia and CKD, this study was performed.

METHODS

Possible sarcopenia was defined according to the Asian Working Group for Sarcopenia in 2019. Participants aged ≥ 40 years were recruited from the baseline survey of the China Health and Retirement Longitudinal Study and followed up for four years. Binary logistic regression was used to evaluate the cross-sectional and longitudinal associations between possible sarcopenia, low muscle strength, low physical performance and CKD. Propensity score matching was used to balance the intergroup differences. Subgroup and interactive analyses were adopted to identify potential interactive effects. Mendelian Randomization analysis was used to assess the causal association between appendicular lean mass (ALM) and CKD.

RESULTS

After data cleansing, a total of 7296 participants were included in the baseline survey. In the cross-sectional analyses, the odds ratios (ORs) of prevalent CKD were 1.50 (95% CI = 1.23-1.84, p < 0.001) for possible sarcopenia, 1.37 (95% CI = 1.10-1.70, p < 0.01) for low muscle strength and 1.42 (95% CI = 1.16-1.74, p < 0.001) for low physical performance in the full models. No significant interaction effects of covariates were detected (all P for interaction > 0.05). After four years of follow-up, an increased risk of incident CKD was also observed in participants with possible sarcopenia (OR = 1.66, 95% CI = 1.13-2.44, p = 0.010) and low physical performance (OR = 1.69, 95% CI = 1.16-2.45, p = 0.006), but not in participants with low muscle strength (OR = 1.19, 95% CI = 0.75-1.88, p = 0.469). In the Mendelian Randomization analysis, the inverse variance weighted estimator showed that a 1-standard deviation increase of genetically predicted ALM was associated with a lower risk of CKD (OR = 0.92, 95% CI = 0.85-0.99, p = 0.035). All the sensitivity analyses supported the main findings.

CONCLUSIONS

Possible sarcopenia is an independent risk factor for CKD and may serve as a predictor of CKD for early identification and intervention.

sEMG-based Sarcopenia risk classification using empirical mode decomposition and machine learning algorithms

Early detection of the risk of sarcopenia at younger ages is crucial for implementing preventive strategies, fostering healthy muscle development, and minimizing the negative impact of sarcopenia on health and aging. In this study, we propose a novel sarcopenia risk detection technique that combines surface electromyography (sEMG) signals and empirical mode decomposition (EMD) with machine learning algorithms. First, we recorded and preprocessed sEMG data from both healthy and at-risk individuals during various physical activities, including normal walking, fast walking, performing a standard squat, and performing a wide squat. Next, electromyography (EMG) features were extracted from a normalized EMG and its intrinsic mode functions (IMFs) were obtained through EMD. Subsequently, a minimum redundancy maximum relevance (mRMR) feature selection method was employed to identify the most influential subset of features. Finally, the performances of state-of-the-art machine learning (ML) classifiers were evaluated using a leave-one-subject-out cross-validation technique, and the effectiveness of the classifiers for sarcopenia risk classification was assessed through various performance metrics. The proposed method shows a high accuracy, with accuracy rates of 0.88 for normal walking, 0.89 for fast walking, 0.81 for a standard squat, and 0.80 for a wide squat, providing reliable identification of sarcopenia risk during physical activities. Beyond early sarcopenia risk detection, this sEMG-EMD-ML system offers practical values for assessing muscle function, muscle health monitoring, and managing muscle quality for an improved daily life and well-being.

Effect of sarcopenia on survival in patients after pancreatic surgery: a systematic review and meta-analysis

Background

Numerous studies have reported sarcopenia to be associated with unfavorable outcomes in patients who have undergone pancreatectomy. Therefore, in this meta-analysis, we examined the relationship between sarcopenia and survival after pancreatic surgery.

Methods

PubMed, Embase, and Cochrane Library were searched for studies that examined the association between sarcopenia and survival after pancreatic surgery from the inception of the database until June 1, 2023. Hazard ratio (HR) for overall survival (OS) and/or progression-free survival (PFS) of sarcopenia and pancreatic surgery were extracted from the selected studies and random or fixed-effect models were used to summarize the data according to the heterogeneity. Publication bias was assessed using Egger's linear regression test and a funnel plot.

Results

Sixteen studies met the inclusion criteria. For 13 aggregated univariate and 16 multivariate estimates, sarcopenia was associated with decreased OS (univariate analysis: HR 1.69, 95% CI 1.48-1.93; multivariate analysis: HR 1.69; 95% CI 1.39-2.05, I2 = 77.4%). Furthermore, sarcopenia was significantly associated with poor PFS of pancreatic resection (Change to univariate analysis: HR 1.74, 95% CI 1.47-2.05; multivariate analysis: HR 1.54; 95% CI 1.23-1.93, I2 = 63%).

Conclusion

Sarcopenia may be a significant prognostic factor for a shortened survival following pancreatectomy since it is linked to an elevated risk of mortality. Further studies are required to understand how sarcopenia affects long-term results after pancreatic resection.Systematic review registrationRegistration ID: CRD42023438208 https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Older adults, appendicular anthropometric measurements, and poor functional performance are predictors of sarcopenia in individuals with head and neck squamous cell carcinoma

OBJECTIVE

To identify predictors of sarcopenia (demographical, anthropometric measurements, tumor-related clinical characteristics, performance status, and serum C-reactive protein (CRP) and albumin levels in individuals with head and neck squamous cell carcinoma (HNSCC).

MATERIAL AND METHODS

This cross-sectional study selected diagnosed with HNSCC (n = 125). Sarcopenia was defined as low muscle strength and low physical performance. Association between sarcopenia and anthropometric assessments (weight, height, body mass index, triceps skinfold, mid-upper arm circumference [MUAC], mid-upper arm muscle circumference, mid-upper arm fat area [UFA], mid-upper arm bone free muscle area, calf circumference, and appendicular skeletal muscle mass and index), tumor clinical characteristics (anatomical site, tumor size, and cervical metastasis), performance status scale (Eastern Cooperative Oncology Group Performance Status [ECOG-PS]), and CRP and albumin levels was analyzed using binary logistic regression models.

RESULTS

The diagnosis of sarcopenia was identified in 28 (22.4%) individuals with HNSCC. Being an older adult increases the odds of association with sarcopenia in individuals with HNSCC (odds ratio [OR] = 1.05). Increments in MUAC measurement reduce the odds of association with sarcopenia (OR = 0.69), while the increase in the UFA measurement increases the odds of association with sarcopenia (OR = 1.33). Poor ECOG-PS scores increase the odds of association with sarcopenia in individuals with HNSCC (OR = 5.54).

CONCLUSION

Early identification of easy-to-perform, cost-effective predictors of sarcopenia tends to favor the implementation of personalized therapeutic and supportive interventions in individuals with HNSCC.

The aspartate aminotransferase to alanine aminotransferase ratio: A novel indicator for skeletal muscle mass in Chinese community adults

OBJECTIVES

The aspartate aminotransferase to alanine aminotransferase (AST/ALT) ratio, an indicator for liver fibrosis, could be easily detected in clinical practice. The aim of this study was to examine the association between the AST/ALT ratio and skeletal muscle mass among Chinese community adult residents.

METHODS

We enrolled 2644 participants, age ≥18 y, undergoing bioelectrical impedance analysis and liver function test. Univariate and multivariate logistic regression models were used to analyze the effect of the AST/ALT ratio on the presence of low muscle mass (LMM). Multiple linear regression analysis was used to assess the factors associated with the skeletal muscle mass index (SMI) and to construct a formula to calculate the SMI.

RESULTS

When the AST/ALT ratio was regarded as a categorical variable, AST/ALT quartiles 9-2.19) kept independent effects on the presence of LMM status. When it was regarded as a continuous variable, each unit of the AST/ALT ratio was significantly associated with a 49% (P < 0.01) augment of the prevalence of LMM. By multiple general linear regression analysis, the formula was constructed with an adjusted R2 of 0.72: SMI (kg/m2) = -0.14 AST/ALT ratio + 1.35 sex (male: 1; female: 0) + 0.72 overweight status (yes: 1; no: 0) - 0.14 age (≤65: 0; >65: 1) + 6.26.

CONCLUSION

In general, the high AST/ALT ratio was an independent adverse indicator of the presence of LMM.

Longitudinal associations between social support and sarcopenia: findings from a 5-year cohort study in Chinese aged ≥50 years

OBJECTIVES

We aimed to investigate longitudinal associations of overall social support and its sub-domains with risk of sarcopenia and its related traits in community-dwelling Chinese aged ≥ 50 years. We also explored interaction effects of potential factors on such associations.

DESIGN

A prospective cohort study.

SETTING

Community-based setting in western China.

PARTICIPANTS

We included participants aged ≥50 years with complete information necessary for analysis from the WCHAT study who did not have sarcopenia at baseline (2018) and had sufficient data for sarcopenia assessment during 2021-2023.

MEASUREMENTS

Exposures included overall social support, subjective support, objective support and support utilization, which were assessed with the Social Support Rating Scale. Outcomes included sarcopenia, low muscle mass (LMM), low muscle strength and low physical performance, which were diagnosed with the 2019 AWGS consensus. Longitudinal associations between the exposures and outcomes were estimated by logistic regression, with generalized estimating equations (GEE) as sensitivity analyses. Subgroup analyses by potential covariates were conducted to detect interaction effects.

RESULTS

A total of 1905 participants were finally included in the analytic sample, of whom 326 (17.1%) developed incident sarcopenia during 5-year follow-up. After controlling for confounders, higher degree of overall social support (OR = 0.87, 95%CI 0.76-0.99), subjective support (OR = 0.88, 95%CI 0.77-0.99) and support utilization (OR = 0.87, 95%CI 0.77-0.99) correlated with lower sarcopenia risk, among which higher support utilization degree was indicative of lower risk for LMM (OR = 0.88, 95%CI 0.79-0.98). GEE further revealed that overall support degree was negatively associated with risk for sarcopenia (OR = 0.86, 95%CI 0.76-0.98) and LMM (OR = 0.87, 95%CI 0.77-0.99). Objective support was neither significantly associated with sarcopenia nor its traits. No significant interaction effect was observed between overall support and the concerned confounders on sarcopenia (interaction P-value > 0.05).

CONCLUSION

Overall social support degree was negatively associated with sarcopenia risk, possibly primarily through affecting muscle mass rather than muscle strength or physical performance, and such an association remained robust across subgroups with distinct characteristics. This holds implications for policymakers to conduct population-based risk assessment, and supportive strategies against sarcopenia should focus on enhancing subjective support and support utilization rather than objective support alone.

Causal associations of plasma omega-3 polyunsaturated fatty acids with sarcopenia-related traits: a two-sample Mendelian randomization study

OBJECTIVE

To evaluate the causal effect of plasma omega-3 polyunsaturated fatty acids (PUFAs) on sarcopenia-related traits (lean mass, grip strength and walking pace) utilizing two-sample Mendelian randomization (MR) approach.

METHODS

Based on genome-wide association study (GWAS) summary statistics, we performed two-sample MR applying the inverse variance weighted (IVW) as the primary method, supplemented with four additional sensitivity analyses. Furthermore, multivariable MR (MVMR) was applied to assess these associations independent of alcohol drinking, type 2 diabetes (T2D), triglycerides (TG), estimated glomerular filtration rate (eGFR) and C-reactive protein (CRP).

RESULTS

In univariable MR, the IVW analysis suggested no significant causal effect of genetically determined plasma omega-3 PUFAs on fat-free mass (right leg: β = 0.01, 95% CI = -0.02 to 0.05, P = 0.375; left leg: β = 0.01, 95% CI = -0.02 to 0.04, P = 0.446; right arm: β = 0.01, 95% CI = -0.02 to 0.05, P = 0.376; left arm: β = 0.01, 95% CI = -0.02 to 0.04, P = 0.384; trunk:β = 0.02, 95% CI = -0.02 to 0.06, P = 0.283; whole: β = 0.01, 95% CI = -0.03 to 0.04, P = 0.631), grip strength (right hand: β = -0.01, 95% CI = -0.03 to 0.01, P = 0.387; left hand: β = -0.01, 95% CI = -0.02 to 0.01, P = 0.553) and walking pace (β = 0.00, 95% CI = -0.01 to 0.02, P = 0.575), and sensitive analysis generated similar non-significant results. Furthermore, the MVMR revealed no independent causal association.

CONCLUSIONS

Genetically determined plasma omega-3 PUFAs have no causal effect on sarcopenia-related traits.

Ethical considerations in sarcopenia research

The Article Abstract is not available.

Decreased serum musclin concentration is independently associated with the high prevalence of sarcopenia in Chinese middle-elderly patients with type 2 diabetes mellitus

INTRODUCTION AND AIMS

Sarcopenia is a complication of diabetes mellitus, which can increase hospitalization and lead to poor outcomes. The present study investigated the relationship between the serum musclin concentration and the sarcopenia morbidity in Chinese middle-elderly patients with type 2 diabetes mellitus.

METHODS

We recruited 220 patients with type 2 diabetes mellitus, all of whom completed gait speed, handgrip strength tests, and whole-body dual-energy x-ray measurements to calculate the appendicular skeletal muscle mass index (ASMI). The patients were divided into sarcopenia (n = 110) and non-sarcopenia groups (n = 110). The serum musclin concentration was measured using an enzyme-linked immunosorbent assay.

RESULTS

The serum musclin concentration was significantly lower in the sarcopenia group (712.82 pg/mL) than in the non-sarcopenia group (922.53 pg/mL). The serum musclin concentration positively correlated with the whole-body skeletal mass (r = 0.230; P = 0.001). Sarcopenia morbidity declined as the quartile of serum musclin concentration increased (P = 0.001), and a negative correlation was observed between the serum musclin concentration and the prevalence of sarcopenia (odds ratio = 0.998, P = 0.001). The correlation remained when quartiles were considered.

CONCLUSIONS

The serum musclin concentration is an independent protective factor for sarcopenia in Chinese middle-elderly patients with type 2 diabetes mellitus.

Targeted optimum care approach for osteoporotic fragility fractures: tailored strategy based on risk stratification to reduce incidents of falls-an initiative by the Egyptian Academy of bone health based on the FLS national register

Since falling is the third cause of chronic disability, a better understanding of the frequency, severity, and risk factors of falls across diagnostic groups is needed to design and implement customized, effective fall prevention, and management programs for these individuals, particularly those at risk of sustaining a fragility fracture.

OBJECTIVE

(1) To assess the incidence of falls among osteoporotic patients with fragility fractures. (2) To evaluate the potential for stratifying the people at risk of falling in bone health setting aiming to provide targeted optimum care for them.

METHODS

This was a multi-center, cross-sectional, observational study. Both men and postmenopausal women, admitted with an osteoporotic fracture (whether major osteoporosis or hip fracture), were consecutively recruited for this work and managed under Fracture Liaison Service. All the patients were assessed for their Fracture risk (FRAX), falls risk (FRAS), and sarcopenia risk (SARC-F) as well as functional disability (HAQ). Blood tests for bone profile as well as DXA scan were offered to all the patients.

RESULTS

Four hundred five patients (121 males, 284 females) were included in this work. Mean age was 70.1 (SD = 9.2) years. The incidence of falls was 64.9%. The prevalence of falls was high (64.8%) in the patients presenting with major osteoporosis fractures and in those with hip fractures (61.8%). The prevalence of fragility fractures was positively correlated with HAQ score and the SARC-F score (p = 0.01 and 0.021 respectively). Falls risk score was positively correlated with FRAX score of major osteoporotic fractures, HAQ score, and SARC-F score (p = 0.01, 0.013, and 0.003 respectively). Seventy percent of the osteopenia patients who sustained fragility fracture had high falls risk and/or SARC-F score.

CONCLUSION

This study highlighted the importance of falls risk stratification in osteoporotic patients presenting with fragility fractures. Identification of the patients at increased risk of falls should be a component of the standard practice.

The association of vitamin D with bone microarchitecture, muscle strength, and mobility performance in older women in long-term care

BACKGROUND

Osteoporosis and sarcopenia are prevalent in older adults. Trabecular bone score (TBS) is a novel method to evaluate bone microarchitecture, whereas grip strength and gait speed are simple methods to assess muscle strength and function. Few studies have linked the relationship between vitamin D levels (25OHD) with TBS, grip strength, and gait speed in healthy community dwelling adults. We sought to investigate this relationship in older women with osteoporosis and multiple comorbid conditions residing in long-term care (LTC) facilities.

METHODS

We analyzed baseline 25OHD, spine TBS, grip strength, and gait speed in 246 women with osteoporosis who were residents of LTC and enrolled in a randomized controlled clinical trial.

RESULTS

On average, participants were 81.6 years old and had a BMI of 26.8 kg/m2. The correlation (r) of 25OHD with spine TBS, grip strength, and gait speed were (r = 0.15; p = 0.0208), (r = - 0.05; p = 0.4686), and (r = 0.19; p = 0.0041), respectively. Each 5 ng/dl increase in 25OHD was associated with an increase of 0.006 in spine TBS and 0.014 m/s in gait speed. After adjusting for covariates, each 5 ng/dl increase in 25OHD was associated with an increase of 0.004 in spine TBS (p = 0.0599) and 0.012 m/s in gait speed (p = 0.0144).

CONCLUSION

In older women residing in LTC facilities, 25OHD was associated with spine TBS and gait speed. The strengths of the associations suggest there may be other factors with a more prominent role in bone microarchitecture, muscle strength, and physical function in this population.

MINI ABSTRACT

Our study found in older women who are residents of long-term care facilities, vitamin D level is associated with bone microarchitecture and mobility performance.

Does exercise influence skeletal muscle by modulating mitochondrial functions via regulating MicroRNAs? A systematic review

BACKGROUND

Sarcopenia is the accelerated loss of muscle mass, strength and function. Mitochondrial dysfunction was related to the progression of sarcopenia; meanwhile, microRNAs were regarded as core roles in regulating mitochondrial function. Physical exercise is a well-accepted approach to attenuate sarcopenia, yet very few studies depict the molecular mechanisms. The aim of this systematic review is to explore the potential relationships among physical exercise, mitochondrial function, and microRNAs, which may give new insight for retarding sarcopenia.

METHODS

A systematic literature search was performed in PubMed, Embase and Web of Science. The keywords were combined as "(microRNA OR miR) AND mitochondri* AND muscle AND exercise" and searched in all fields. PRISMA guidelines were followed. Information was extracted from the included studies for review.

RESULTS

In this review, 18 preclinical studies and 5 clinical studies were included. Most of the included studies suggested that effective physical exercise had positive effects on mitochondrial functions by regulating microRNAs. The results showed that 12 microRNAs improved mitochondrial functions, while 18 microRNAs suppressed them. Meanwhile, the results showed that 5 microRNAs improved muscle performance.

CONCLUSIONS

This systematic review provides an up-to-date sequential overview and highlights the potential relationship among exercise, mitochondrial function, and microRNAs in muscle. Meanwhile, evidence revealed that physical exercise can improve muscle performance by up-regulating mitochondrial functions, especially mitochondrial biogenesis, through modulating microRNAs.

Sarcopenic Obesity and Cardiometabolic Health and Mortality in Older Adults: a Growing Health Concern in an Ageing Population

PURPOSE OF REVIEW

Sarcopenic obesity (SO) is a growing public health problem in older adults. Whether SO confers higher risk of cardiometabolic disease and mortality than obesity or sarcopenia alone is still a matter of debate. We focus on recent findings on SO and cardiometabolic health and mortality in older adults.

RECENT FINDINGS

SO is associated with increased mortality compared to non-sarcopenic obesity, but similar mortality risk compared to sarcopenia without obesity. SO is associated with a higher risk of cardiovascular disease (CVD), diabetes, and physical disability than obesity or sarcopenia alone. SO, in the presence of diabetes, is associated with the highest risk of CVD and chronic kidney disease. A definition and diagnostic criteria for SO has recently been proposed (ESPEN and EASO). SO is associated with more adverse outcomes overall than sarcopenia or obesity alone. Future research is required to assess the impact of the new SO definition on health outcomes.

Effectiveness of Combined Exercise and Nutrition Interventions in Preventing and Improving Sarcopenia in Frail or Healthy Older Adults: A Systematic Review

The current systematic review compared whether combined exercise and nutrition interventions are effective in preventing or improving sarcopenia in frail older adults and healthy older adults. Medline, Embase, Cochrane Library, and CINAHL were searched for randomized controlled trials. Of the 1,596 citations, 22 trials (N = 1,767) were included in the final sample. In frail older adults, significant improvement after combined exercise and nutrition interventions was observed in seven indicators: skeletal muscle index, 0.16 kg/m2; handgrip, 1.41 kg; knee extension strength, 0.24 Nm; five-repetition chair-stand test, -1.89 sec; gait speed, 0.06 m/s; Short Physical Performance Battery, 0.43; and Timed Up and Go test, -0.56 sec. In healthy older adults, two indicators improved and showed statistically significant differences: handgrip, 2.15 kg; and 6-Minute Walking Test, 9.71 m. Combined exercise and nutritional interventions can improve skeletal muscle quality, strength, and physical performance in frail and healthy older adults. [Research in Gerontological Nursing, 16(6), 312-320.].

Regeneration of neuromuscular synapses after acute and chronic denervation by inhibiting the gerozyme 15-prostaglandin dehydrogenase

To date, there are no approved treatments for the diminished strength and paralysis that result from the loss of peripheral nerve function due to trauma, heritable neuromuscular diseases, or aging. Here, we showed that denervation resulting from transection of the sciatic nerve triggered a marked increase in the prostaglandin-degrading enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in skeletal muscle in mice, providing evidence that injury drives early expression of this aging-associated enzyme or gerozyme. Treating mice with a small-molecule inhibitor of 15-PGDH promoted regeneration of motor axons and formation of neuromuscular synapses leading to an acceleration in recovery of force after an acute nerve crush injury. In aged mice with chronic denervation of muscles, treatment with the 15-PGDH inhibitor increased motor neuron viability and restored neuromuscular junctions and function. These presynaptic changes synergized with previously reported muscle tissue remodeling to result in a marked increase in the strength of aged muscles. We further found that 15-PGDH aggregates defined the target fibers that are histopathologic hallmarks of human neurogenic myopathies, suggesting that the gerozyme may be involved in their etiology. Our data suggest that inhibition of 15-PGDH may constitute a therapeutic strategy to physiologically boost prostaglandin E2, restore neuromuscular connectivity, and promote recovery of strength after acute or chronic denervation due to injury, disease, or aging.

Multidisciplinary approach to sarcopenia: a narrative review

Sarcopenia is a condition in which muscle mass and strength are decreased and muscle function is impaired. It is an indicator of frailty and loss of independence in older adults. It is also associated with increased physical disability, which increases the risk of falls. As a multifactorial disease, sarcopenia is caused by a combination of factors including aging, hormonal changes, nutritional deficiencies, and physical inactivity. Understanding the underlying pathophysiology of sarcopenia and identifying its different causes is critical to developing effective prevention and treatment strategies. This review summarizes the pathophysiology, consequences, diagnostic methods, and multidisciplinary approaches to sarcopenia.

Knowledge, attitude, and practice regarding sarcopenia: a survey between orthopedic and geriatric professionals in China

BACKGROUND

In elderly patients with fractures, sarcopenia impairs recovery and even increases mortality. Both orthopedic and geriatric professionals are at the forefront of treating sarcopenic patients with fractures. However, it is not clear to what extent they have knowledge and skills to diagnose and treat sarcopenia.

AIMS

This study aimed to analyze and compare knowledge, attitude, and practice regarding sarcopenia between orthopedic and geriatric professionals.

METHODS

An online cross-sectional survey was conducted in June 2022 targeting professionals in orthopedic and geriatric departments in two largest tertiary general hospitals in Taizhou, southeastern China. Results on knowledge, attitude, and practice of sarcopenia were analyzed. Variables with significance were then included in a stepwise multiple linear regression analysis.

RESULTS

A total of 220 professionals, 176 from orthopedic departments and 44 from geriatric departments, participated in this study. Orthopedic professionals scored lower than geriatrics in knowledge, attitude and practice (P < 0.001). The attitude score was high in both orthopedic and geriatric professionals. Stepwise multiple linear regression analysis showed that participants who had contact with sarcopenia patients had higher knowledge score (β = 1.941, P < 0.001); participants who had attended sarcopenia training in the past 6 months (β = 4.305, P < 0.001) had higher practice score.

DISCUSSION

Orthopedic professionals have deficiencies in the screening and diagnosis of sarcopenia. Improving the knowledge and training of professionals can strengthen practice. It is necessary to formulate diagnostic criteria and improve practice of sarcopenia through training.

CONCLUSION

Orthopedic professionals had limited knowledge and practice regarding sarcopenia compared with geriatric professionals. To improve sarcopenia practice, the use of diagnostic tools to formally diagnose sarcopenia and regular training on sarcopenia should be encouraged.

Association of dietary patterns and sarcopenia in the elderly population: a cross-sectional study

Background: Sarcopenia, defined as the loss of muscle mass and strength, has been associated with increased hospitalization and mortality. Dietary pattern analysis is a whole diet approach which in this study was used to investigate the relationship between diet and sarcopenia. This study aims to estimate the prevalence of sarcopenia and explore possible factors associated with it among a large population in Beijing, China. Methods: A cross-sectional study with 1,059 participants aged more than 50 years was performed. Sarcopenia was defined based on the guidelines of the Asian Working Group for Sarcopenia. The total score of the MNA-SF questionnaire was used to analyse nutrition status. The baseline demographic information, diet structure and eating habits were collected by clinicians trained in questionnaire data collection and anthropometric and bioimpedance measurements. Results: The overall prevalence of sarcopenia was 8.8% and increased with age: 5%, 5.8%, 10.3% and 26.2% in the 50-59, 60-69, 70-79, and ≥80 years groups, respectively. Marital status (with or without a spouse) was not an independent factor associated with sarcopenia adjusted by age and sex. However, nutritional risk or malnutrition, vegetable diet, advanced age and spicy eating habits were risk factors for sarcopenia. Meanwhile, daily fruit, dairy and nut consumption were protective factors against sarcopenia adjusted by age, sex, income status and spouse status. Conclusion: Although further studies are required to explore the association between healthy dietary patterns and the risk of sarcopenia, the present study provides basic data for identifying correlates of sarcopenia in elderly Chinese individual.

Role of adipokines in sarcopenia

ABSTRACT

Sarcopenia is an age-related disease that mainly involves decreases in muscle mass, muscle strength and muscle function. At the same time, the body fat content increases with aging, especially the visceral fat content. Adipose tissue is an endocrine organ that secretes biologically active factors called adipokines, which act on local and distant tissues. Studies have revealed that some adipokines exert regulatory effects on muscle, such as higher serum leptin levels causing a decrease in muscle function and adiponectin inhibits the transcriptional activity of Forkhead box O3 (FoxO3) by activating peroxisome proliferators-activated receptor-γ coactivator -1α (PGC-1α) and sensitizing cells to insulin, thereby repressing atrophy-related genes (atrogin-1 and muscle RING finger 1 [MuRF1]) to prevent the loss of muscle mass. Here, we describe the effects on muscle of adipokines produced by adipose tissue, such as leptin, adiponectin, resistin, mucin and lipocalin-2, and discuss the importance of these adipokines for understanding the development of sarcopenia.

The acceptability of homebased exercise snacking and Tai-chi snacking amongst high and low function UK and Taiwanese older adults

Introduction: Exercise "snacking" and Tai-chi 'snacking' protocols are designed to overcome typical barriers to older adults' participation in muscle strength and balance exercise, using short bouts of home-based exercise. This study aimed to investigate the acceptability of homebred exercise- and Tai-chi snacking in British and Taiwanese older adults of high and low physical function. Methods: Thirty-three British and Thirty Taiwanese older adults took part in semi-structured interviews, after trying 1-week of exercise- and Tai-chi snacking. The interview schedule and deductive framework analysis was based on the seven components of the Theoretical Framework of Acceptability (TFA). Differences between the Taiwanese and United Kingdom participants and those considered high versus low physical function were also analysed. Results: Both snacking regimes were found to be convenient and easy to implement. Participants reported that no activity had to be given up, and considered the programmes would be beneficial to their physical and mental health. Interestingly, more UK-based participants preferred the elegant and relaxing movements of Tai-chi snacking, yet participants with low physical function experienced difficulties when mastering Tai-chi movements. A few high physical function participants perceived exercise snacking to be tedious. Discussion: Overall, the snacking exercise was found to be acceptable and useful. Personal affective attitude and different cultural backgrounds may affect exercise participation. Nevertheless, it is important to consider individuals' physical function when designing exercise regime. The findings indicate that making Tai-chi snacking easier to master initially, building in progression and adding some upper body movements in the exercise snacking may further enhance acceptability.

Possible-sarcopenic screening with disturbed plasma amino acid profile in the elderly

BACKGROUND

The mass and strength of skeletal muscle decline with age, leading to its progressive dysfunction. High-throughput metabolite profiling provides the opportunity to reveal metabolic mechanisms and the identification of biomarkers. However, the role of amino acid metabolism in possible sarcopenia remains unclear.

OBJECTIVES

The aim of this study included exploring variations in plasma amino acid concentrations in elderly individuals who have possible sarcopenia and further attempting to characterize a distinctive plasma amino acid profile through targeted metabolomics.

METHODS

A cross-sectional, correlational research design was used for this study. Thirty possible-sarcopenic elderly participants were recruited (n = 30), as determined by the Asian Working Group for Sarcopenia (AWGS). Meanwhile, a reference group of non-sarcopenic (sex-, age-, and Appendicular Skeletal muscle Mass Index (ASMI)-matched non-sarcopenic controls, n = 36) individuals was included to compare the potential differences in metabolic fingerprint of the plasma amino acids associated with sarcopenia. Both groups were conducted the body composition analysis, physical function examination, and plasma amino acid-targeted metabolomics. The amino acids in plasma were measured using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS). Also, orthogonal partial least-squares-discriminant analysis (OPLS-DA) was applied to characterize the plasma amino acid profile.

RESULTS

With respect to Handgrip Strength (HGS), the Five-Repetition Chair Stand Test (CS-5), the Six-Minute Walking Test (6MWT), the arm curl, the 30 s-Chair Stand Test (CST), the 2-Minute Step Test (2MST), the Timed Up-and-Go Test (TUGT), there was a decline in skeletal muscle function in the possible-sarcopenic group compared to the non-sarcopenic group. The mean plasma concentrations of arginine, asparagine, phenylalanine, serine, lysine, glutamine, and threonine were significantly lower in the possible sarcopenia group, whereas cirulline, proline, serine, and glutamic acid concentrations were higher. According to the multi-analysis, glutamine, serine, lysine, threonine, and proline were determined as the potential markers that indicated possible sarcopenia.

CONCLUSIONS

The findings characterize significantly altered plasma amino acid metabolisms in the elderly with possible sarcopenia, which aids to screening people who are at a high risk of developing condition, and motivating to design new preventive and therapeutic approaches.

A tool to assess fitness among adults in public health studies - Predictive validity of the FFB-Mot questionnaire

BACKGROUND

Fitness has important implications for physical activity behavior and is associated with various health-related outcomes. It can be assessed through a test battery or a self-reported questionnaire. One example is the FFB-Mot (Funktionsfragebogen Motorik; engl. functional fitness questionnaire) which consist of 28 items to assess four components of fitness in adults: cardiorespiratory fitness/ endurance, muscular strength, gross motor coordination, and flexibility. The aims of this manuscript were to (1) provide an English-version of the FFB-Mot questionnaire (developed from the German-version using translation and back-translation) to the international community of researchers in the areas of physical activity, fitness and health in adults, and (2) examine the predictive validity of the FFB-Mot questionnaire in a large sample of community-dwelling adults.

METHODS

We used data from a longitudinal study in Germany with four measurement waves over a period of 18 years, with samples ranging between 310 and 437 participants (1572 adults in total, mean ages 46-58 years). To assess predictive validity, we calculated Pearson correlations between FFB-Mot data collected in 1997 and external health-related criteria (i.e., subjective health status, physician-rated health status, back pain, physical complaints and physical activity in minutes per week) collected in 2002, 2010, and 2015, and separately for males and females.

RESULTS

We observed correlations between higher FFB-Mot scores with better subjective health status (in 2002: males, r = 0.25; females, r = 0.18; in 2010: males, r = 0.29; females, r = 0.28; in 2015: males, r = 0.40), and higher physical activity (in 2002: males, r = 0.24; females, r = 0.25; in 2010: males, r = 0.30; females, r = 0.38; in 2015: females, r = 0.27). Higher FFB-Mot scores were also correlated with lower back pain (in 2002: males, r = -0.23; females, r = -0.25; in 2010: females, r = -0.22), less physical complaints (in 2002: males, r = -0.36; females, r = -0.24), and better physician-rated health status (in 2002: males, r = -0.41; females, r = -0.29, 2010: males, r = -0.38; females, r = -0.44; in 2015: males, r = -0.47).

CONCLUSIONS

Our results suggest that the FFB-Mot to assess fitness in adults has predictive validity for health-related outcomes as indicated by significant correlations, albeit some effect sizes are small. The FFB-Mot may be used as one-time assessment of self-reported fitness, or for repeated testing to assess change of self-reported fitness over time and in different settings (e.g., public health research).

Minerals and Sarcopenia in Older Adults: An Updated Systematic Review

OBJECTIVE

This systematic review aims to reevaluate the role of minerals on muscle mass, muscle strength, physical performance, and the prevalence of sarcopenia in community-dwelling and institutionalized older adults.

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

In March 2022, a systematic search was performed in PubMed, Scopus, and Web of Sciences using predefined search terms. Original studies on dietary mineral intake or mineral serum blood concentrations on muscle mass, muscle strength, and physical performance or the prevalence of sarcopenia in older adults (average age ≥65 years) were included.

METHODS

Eligibility screening and data extraction was performed by 2 independent reviewers. Quality assessment was performed with the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies. Risk of bias was evaluated using the Risk Of Bias In Non-randomized Studies-of Exposure (ROBINS-E) tool.

RESULTS

From the 15,622 identified articles, a total of 45 studies were included in the review, mainly being cross-sectional and observational studies. Moderate quality of evidence showed that selenium (n = 8) and magnesium (n = 7) were significantly associated with muscle mass, strength, and physical performance as well as the prevalence of sarcopenia. For calcium and zinc, no association could be found. For potassium, iron, sodium, and phosphorus, the association with sarcopenic outcomes remains unclear as not enough studies could be included or were nonconclusive (low quality of evidence).

CONCLUSIONS AND IMPLICATIONS

This systematic review shows a potential role for selenium and magnesium on the prevention and treatment of sarcopenia in older adults. More randomized controlled trials are warranted to determine the impact of minerals on sarcopenia in older adults.

Muscle Traits, Sarcopenia, and Sarcopenic Obesity: A Vitamin D Mendelian Randomization Study

(1) Background: Observational studies associate vitamin D deficiency with muscle disorders, while some clinical trial data support a minor association between the vitamin and skeletal muscle performance in healthy subjects. Vitamin D receptor knockout mice studies confirm the relationship between vitamin D and skeletal muscle; however, causal inference in humans is challenging due to the ethical implications of including vitamin D-deficient participants in randomized trials. This study uses genetic methods to safely explore causal underpinnings for the relationship between 25(OH)D concentrations and skeletal muscle-related traits, including grip strength and combined arm skeletal muscle mass, and extends this analysis to suspected pathophysiology in the form of probable sarcopenia and sarcopenic obesity. (2) Methods: We conducted Mendelian randomization (MR) analyses in up to 307,281 participants from the UK Biobank of whom 25,414 had probable sarcopenia and 16,520 had sarcopenic obesity. In total, 35 variants were used to instrument 25(OH)D and MR analyses conducted using multiple approaches. (3) Results: Genetic analyses provided support for a relationship between genetically predicted higher 25(OH)D and skeletal muscle traits, with linear MR analyses for grip strength showing 0.11 kg (95% CI 0.04, 0.19) greater contractile force per 10 unit higher 25(OH)D, while there was a modest association with skeletal muscle mass (0.01 kg (95% CI 0.003, 0.02) greater muscle mass). For probable sarcopenia risk, there was suggestive evidence for lower odds by higher 25(OH)D (OR 0.96 (95% CI 0.92, 1.00)); however, this did not reflect an association with sarcopenic obesity (OR 0.97 (95% CI 0.93, 1.02)), but was seen in probable sarcopenia cases who were not obese (OR 0.92 (95% CI 0.86, 0.98)). Results were similar across multiple MR approaches. (4) Conclusions: Our study supports a causal relationship between 25(OH)D and skeletal muscle health. While evidence for benefit did not extend to lower risk of sarcopenic obesity, effective vitamin D-deficiency prevention strategies may help reduce age-related muscle weakness.

Caloric Restriction Combined with Immobilization as Translational Model for Sarcopenia Expressing Key-Pathways of Human Pathology

The prevalence of sarcopenia is increasing while it is often challenging, expensive and time-consuming to test the effectiveness of interventions against sarcopenia. Translational mouse models that adequately mimic underlying physiological pathways could accelerate research but are scarce. Here, we investigated the translational value of three potential mouse models for sarcopenia, namely partial immobilized (to mimic sedentary lifestyle), caloric restricted (CR; to mimic malnutrition) and a combination (immobilized & CR) model. C57BL/6J mice were calorically restricted (-40%) and/or one hindleg was immobilized for two weeks to induce loss of muscle mass and function. Muscle parameters were compared to those of young control (4 months) and old reference mice (21 months). Transcriptome analysis of quadriceps muscle was performed to identify underlying pathways and were compared with those being expressed in aged human vastus lateralis muscle-biopsies using a meta-analysis of five different human studies. Caloric restriction induced overall loss of lean body mass (-15%, p<0.001), whereas immobilization decreased muscle strength (-28%, p<0.001) and muscle mass of hindleg muscles specifically (on average -25%, p<0.001). The proportion of slow myofibers increased with aging in mice (+5%, p<0.05), and this was not recapitulated by the CR and/or immobilization models. The diameter of fast myofibers decreased with aging (-7%, p<0.05), and this was mimicked by all models. Transcriptome analysis revealed that the combination of CR and immobilization recapitulated more pathways characteristic for human muscle-aging (73%) than naturally aged (21 months old) mice (45%). In conclusion, the combination model exhibits loss of both muscle mass (due to CR) and function (due to immobilization) and has a remarkable similarity with pathways underlying human sarcopenia. These findings underline that external factors such as sedentary behavior and malnutrition are key elements of a translational mouse model and favor the combination model as a rapid model for testing the treatments against sarcopenia.