Sarcopenia and the cardiometabolic syndrome: A narrative review

Effect of Sarcopenia on Coronary Atherosclerotic Burden, Lesion Complexity, and Major Cardiovascular Events in Elderly Patients With Acute Coronary Syndrome: A 1-year Follow-up Study

Sarcopenia is accepted as an indicator of subclinical atherosclerosis. However, its effects on clinical coronary atherosclerotic burden and lesion complexity and major adverse cardiovascular events (MACE) in elderly patients with non-ST elevation myocardial infarction (NSTEMI) are unknown. Therefore, we evaluated these possible effects. Coronary artery disease (CAD) burden and complexity were assessed using the Gensini and TAXus and cardiac surgery (SYNTAX) score, respectively. MACE involving nonfatal myocardial infarction, rehospitalization, ischemic stroke, and total mortality were evaluated after 1 year of the index NSTEMI event. The study included 240 elderly patients; of these, 60 (25%) patients had sarcopenia. The SYNTAX score and Gensini score were similar in both groups (16.8 ± 8.7 vs 17.3 ± 9.2, P = .63 and 67.7 ± 43.9 vs 73.9 ± 45.5, P = .31, respectively). The total MACE rate was significantly higher in patients with sarcopenia than in those without sarcopenia (31.7 vs 14.4%, P = .003). In the multivariate model, age [odds ratio (OR) 1.112, 95% CI: 1.006-1.228, P = .04)], ejection fraction (OR: .923, 95% CI: .897-.951, P < .001), and sarcopenia (OR: 2.262, 95% CI: 1.039-4.924, P = .04) were independently associated with MACE. Sarcopenia was independently associated with MACE but not with CAD burden or complexity in elderly patients with NSTEMI.

Body composition and aging: cross-sectional results from the INSPIRE study in people 20 to 93 years old

Aging is characterized by several major changes, including altered body composition, which is associated with numerous negative clinical consequences such as sarcopenia, osteoporosis, and frailty. The study is to evaluate body composition parameters depending on age and sex in a population ranging from the young adult to the very old, and to identify break points in the association between body composition and age. In this cross-sectional study, we included the enrolment population of the French INSPIRE-T prospective cohort, accounting for 915 subjects (62% female). Age ranged from 20 to 93 years, median age (years) was 63 (IQR 27). Body composition (lean mass, fat mass, and bone mineral content) was assessed with dual-X-ray absorptiometry (DXA). Different break points in the relationship between age and body composition variables in males and females were identified using a segmented regression analysis adjusted on physical activity, nutritional status, educational level, and comorbidities. Lean mass decreased from the age of 55 years for males (CI 95% 44-66) and 31 years for females (CI 95% 23-39). For fat mass, we observed a trend towards an increase with age for males. For females, we observed an increase with age up to age 75 (CI 95% 62-86), followed by a decreasing trend. In this study, we described the relationship between body composition and age as a function of sex, establishing a foundation for further studies on predictive biomarkers of age-related body composition alteration.

Bidirectional Relationships between Sarcopenia and Pelvic Floor Disorders

Sarcopenia and pelvic floor disorders (PFDs) are prevalent and often cooccurring conditions in the aging population. However, their bidirectional relationship and underlying mechanisms remain underexplored. This narrative review aims to elucidate this relationship by exploring potential causative interplays, shared pathophysiological mechanisms, and common risk factors. A comprehensive literature search was conducted to identify relevant studies focusing on epidemiological associations, interaction mechanisms, and implications for patient care. While epidemiological studies demonstrate associations between sarcopenia and PFDs, our findings reveal a cyclical relationship where sarcopenia may exacerbate PFDs through mechanisms such as decreased muscle strength and mobility. Conversely, the presence of PFDs often leads to reduced physical activity due to discomfort and mobility issues, which in turn exacerbate the muscle atrophy associated with sarcopenia. Additionally, shared risk factors such as physical inactivity, nutritional deficiencies, metabolic syndrome, and menopausal hormonal changes likely contribute to the onset and progression of both conditions. These interactions underscore the importance of concurrently integrated care approaches that address both conditions. Effective management requires comprehensive screening, the recognition of contributing factors, and tailored exercise regimens supported by a multidisciplinary approach. Future research should focus on longitudinal studies tracking disease progression and evaluating the efficacy of multidisciplinary care models in optimizing patient outcomes.

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

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

Temporal Muscle Thickness and Sarcopenia Components in Healthy Adults, Validated through Allgeun Diagnostic Tool

Sarcopenia, characterized by progressive muscle loss and functional decline, poses significant risks, including falls, impaired daily activities, and increased mortality. We developed Allgeun, a novel device that measures handgrip strength, muscle mass, and physical performance. This study aimed to investigate whether temporal muscle thickness (TMT) could be used as a sarcopenia marker and to evaluate the usability of Allgeun. This prospective study enrolled 28 participants without medical or neurological disorders. They underwent three-dimensional T1-weighted imaging using a 3 Tesla magnetic resonance imaging scanner. TMT was measured based on T1-weighted images by a board-certified neuroradiologist. Allgeun was used to measure the following three key components of sarcopenia: muscle strength (handgrip strength), muscle mass (calf and thigh circumference), and physical performance (five times the chair stand test). Correlation analysis was conducted between TMT and the results of the handgrip strength, calf and thigh circumferences, and chair stand tests. There were moderate positive correlations between TMT and calf circumference (r = 0.413, p = 0.029), thigh circumference (r = 0.486, p = 0.008), and handgrip strength (r = 0.444, p = 0.018). However, no significant correlation was observed between TMT and physical performance (r = -0.000, p = 0.998). Our findings underscore TMT's potential as an indicator of sarcopenia, particularly regarding muscle mass and strength. Additionally, we demonstrated that the new device, Allgeun, is useful for screening and diagnosing the severity of sarcopenia.

Associations between life's essential 8 and sarcopenia in US adults: a cross-sectional analysis

Cardiovascular disease (CVD) is closely associated with sarcopenia. We aimed to examine the relationship between Life's Essential 8 (LE8) and the incidence of sarcopenia among adults in the United States. In this study, a cross-sectional analysis was conducted using data from the National Health and Nutrition Examination Survey from 2013 to 2018 and included 5999 adult participants. LE8 score was categorized into low (< 49), moderate (49-79), and high CVH (≥ 79) groups and consisted of health behavior score and health factor score based on American Heart Association definitions. Sarcopenia was defined according to The Foundation for the National Institutes of Health Sarcopenia Project. Multivariate logistic regressions, restricted cubic spline regressions, and subgroup analyses were used to assess the association between LE8 and sarcopenia. LE8 and its subscales score were negatively associated with the incidence of sarcopenia in US adults.

Linking sarcopenia, brain structure and cognitive performance: a large-scale UK Biobank study

Sarcopenia refers to age-related loss of muscle mass and function and is related to impaired somatic and brain health, including cognitive decline and Alzheimer's disease. However, the relationships between sarcopenia, brain structure and cognition are poorly understood. Here, we investigate the associations between sarcopenic traits, brain structure and cognitive performance. We included 33 709 UK Biobank participants (54.2% female; age range 44-82 years) with structural and diffusion magnetic resonance imaging, thigh muscle fat infiltration (n = 30 561) from whole-body magnetic resonance imaging (muscle quality indicator) and general cognitive performance as indicated by the first principal component of a principal component analysis across multiple cognitive tests (n = 22 530). Of these, 1703 participants qualified for probable sarcopenia based on low handgrip strength, and we assigned the remaining 32 006 participants to the non-sarcopenia group. We used multiple linear regression to test how sarcopenic traits (probable sarcopenia versus non-sarcopenia and percentage of thigh muscle fat infiltration) relate to cognitive performance and brain structure (cortical thickness and area, white matter fractional anisotropy and deep and lower brain volumes). Next, we used structural equation modelling to test whether brain structure mediated the association between sarcopenic and cognitive traits. We adjusted all statistical analyses for confounders. We show that sarcopenic traits (probable sarcopenia versus non-sarcopenia and muscle fat infiltration) are significantly associated with lower cognitive performance and various brain magnetic resonance imaging measures. In probable sarcopenia, for the included brain regions, we observed widespread significant lower white matter fractional anisotropy (77.1% of tracts), predominantly lower regional brain volumes (61.3% of volumes) and thinner cortical thickness (37.9% of parcellations), with |r| effect sizes in (0.02, 0.06) and P-values in (0.0002, 4.2e-29). In contrast, we observed significant associations between higher muscle fat infiltration and widespread thinner cortical thickness (76.5% of parcellations), lower white matter fractional anisotropy (62.5% of tracts) and predominantly lower brain volumes (35.5% of volumes), with |r| effect sizes in (0.02, 0.07) and P-values in (0.0002, 1.9e-31). The regions showing the most significant effect sizes across the cortex, white matter and volumes were of the sensorimotor system. Structural equation modelling analysis revealed that sensorimotor brain regions mediate the link between sarcopenic and cognitive traits [probable sarcopenia: P-values in (0.0001, 1.0e-11); muscle fat infiltration: P-values in (7.7e-05, 1.7e-12)]. Our findings show significant associations between sarcopenic traits, brain structure and cognitive performance in a middle-aged and older adult population. Mediation analyses suggest that regional brain structure mediates the association between sarcopenic and cognitive traits, with potential implications for dementia development and prevention.

Prospective observational study of nutritional status and oral supplement utilization in users of an elderly daycare service, employing a web-based Mini Nutritional Assessment Form (MNA plus)

Introduction

Seniors are vulnerable to frailty, a condition linked to falls, fractures, hospitalizations, and sarcopenia. Even with regular meals, senior daycare users are at risk for malnutrition.

Methods

This study assessed malnutrition risk in daycare users, using the web-based Mini Nutritional Assessment Form (MNA®-SF). Individuals identified as malnourished or at risk were examined for changes in nutritional status with and without oral nutritional supplementation (ONS).

Results

Of 507 subjects, 138 (27.2%) were malnourished or at risk. Discontinuation rates were 20.0% (7/35) for the ONS group and 40.0% (10/25) for the regular care (RC) group. Among 29 patients with measurable weight change after six months, 19 (ONS group) and 10 (RC group) participated. The ONS group exhibited significant increases in body weight (+1.4 ± 2.9 kg, p < 0.01), body mass index (BMI) (+0.6 ± 0.9 kg/m2, p < 0.01), calf circumference (+3.2 ± 0.2 cm, p < 0.01), and grip strength (+1.2 ± 1.9 kg, p = 0.069). Conversely, the RC group showed no significant increases in body weight (+1.0 ± 1.9 kg, p = 0.146), BMI (+0.4 ± 0.8 kg/m2, p = 0.176), or grip strength (-0.7 ± 1.7 kg, p = 0.327), with decreased grip strength and calf circumference (-0.8 ± 0.9 cm, p < 0.05). In the ONS group, 52.6% (10/19) consumed over 400 kcal/day of ONS, and 84.2% maintained this intake for three months. Malnutrition is prevalent among daycare users.

Conclusion

ONS influences weight, BMI, and calf circumference, potentially reducing discontinuation rates.

Clinical trial registration

https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000049767, UMIN000043580.

The association of appendicular lean mass and grip strength with low-density lipoprotein, very low-density lipoprotein, and high-density lipoprotein particle diameter: a Mendelian randomization study of the UK Biobank cohort

Aims

Reduced muscle mass and reduced strength are frequently associated with both alterations in blood lipids and poorer cardiometabolic outcomes in epidemiological studies; however, a causal association cannot be determined from such observations. Two-sample Mendelian randomization (MR) was applied to assess the association of genetically determined appendicular lean mass (ALM) and handgrip strength (HGS) with serum lipid particle diameter.

Methods and results

Mendelian randomization was implemented using summary-level data from the largest genome-wide association studies on ALM (n = 450 243), HGS (n = 223 315), and lipoprotein [low-density lipoprotein (LDL), very LDL (VLDL), and high-density lipoprotein (HDL)] particle diameters (n = 115 078). Inverse variance-weighted (IVW) method was used to calculate the causal estimates. Weighted median-based method, MR-Egger, and leave-one-out method were applied as sensitivity analysis. Greater ALM had a statistically significant positive effect on HDL particle diameter (MR-Egger: β = 0.055, SE = 0.031, P = 0.081; IVW: β = 0.068, SE = 0.014, P < 0.001) and a statistically significant negative effect on VLDL particle diameter (MR-Egger: β = -0.114, SE = 0.039, P = 0.003; IVW: β = -0.081, SE = 0.017, P < 0.001). Similarly, greater HGS had a statistically significant positive effect on HDL particle diameter (MR-Egger: β = 0.433, SE = 0.184, P = 0.019; IVW: β = 0.121, SE = 0.052, P = 0.021) and a statistically significant negative effect on VLDL particle diameter (MR-Egger: β = -0.416, SE = 0.163, P = 0.011; IVW: β = -0.122, SE = 0.046, P = 0.009). There was no statistically significant effect of either ALM or HGS on LDL particle diameter.

Conclusion

There were potentially causal associations between both increasing ALM and HGS and increasing HDL particle size and decreasing VLDL particle size. These causal associations may offer possibilities for interventions aimed at improving cardiovascular disease risk profile.

Nutrition as the foundation for successful aging: a focus on dietary protein and omega-3 polyunsaturated fatty acids

Skeletal muscle plays a critical role throughout the aging process. People living with sarcopenia, a progressive and generalized loss of skeletal muscle mass and function, often experience diminished quality of life, which can be attributed to a long period of decline and disability. Therefore, it is important to identify modifiable factors that preserve skeletal muscle and promote successful aging (SA). In this review, SA was defined as (1) low cardiometabolic risk, (2) preservation of physical function, and (3) positive state of wellbeing, with nutrition as an integral component. Several studies identify nutrition, specifically high-quality protein (eg, containing all essential amino acids), and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), as positive regulators of SA. Recently, an additive anabolic effect of protein and n-3 PUFAs has been identified in skeletal muscle of older adults. Evidence further suggests that the additive effect of protein and n-3 PUFAs may project beyond skeletal muscle anabolism and promote SA. The key mechanism(s) behind the enhanced effects of intake of protein and n-3 PUFAs needs to be defined. The first objective of this review is to evaluate skeletal muscle as a driver of cardiometabolic health, physical function, and wellbeing to promote SA. The second objective is to examine observational and interventional evidence of protein and n-3 PUFAs on skeletal muscle to promote SA. The final objective is to propose mechanisms by which combined optimal intake of high-quality protein and n-3 PUFAs likely play a key role in SA. Current evidence suggests that increased intake of protein above the Recommended Dietary Allowance and n-3 PUFAs above the Dietary Guidelines for Americans recommendations for late middle-aged and older adults is required to maintain skeletal muscle mass and to promote SA, potentially through the mechanistical target of rapamycin complex 1 (mTORC1).

Correlation between preoperative CT scan of the paraspinal, psoas, and gluteus muscles and postoperative ambulatory status in patients with femoral neck fractures

BACKGROUND

This study aimed to investigate the relationship between femoral neck fractures and sarcopenia.

METHODS

This was a retrospective analysis of 92 patients with femoral neck fractures, from September 2017 to March 2020, who were classified into high ambulatory status (HG) and low ambulatory status (LG) groups. Ambulatory status was assessed before surgery, one week after surgery, at discharge, and during the final follow-up. To evaluate sarcopenia, muscle mass and fatty degeneration of the muscles were measured using preoperative CT. An axial slice of the superior end of the L5 vertebra was used to evaluate the paraspinal and psoas muscles, a slice of the superior end of the femoral head for the gluteus maximus muscle, and a slice of the inferior end of the sacroiliac joint for the gluteus medius muscle. The degeneration of the muscles was evaluated according to the Goutallier classification.

RESULTS

The cross-sectional area of the gluteus medius and paraspinal muscles was significantly correlated with ambulatory status before the injury, at discharge, and during the final follow-up.

CONCLUSIONS

Measurement of the gluteus medius and paraspinal muscles has the potential to evaluate sarcopenia and predict ambulatory status after femoral neck fractures.

Association between sarcopenia and multimorbidity among middle-aged and older adults in China: Findings from the China Health and Retirement Longitudinal Study

BACKGROUND

Little is known about the association between sarcopenia and multimorbidity among middle-aged and older adults. This study investigated whether sarcopenia is associated with multimorbidity in middle-aged and older Chinese individuals.

MATERIALS AND METHODS

A total of 12,760 participants from China Health and Retirement Longitudinal Study (CHARLS) 2015, with data on 14 specified chronic diseases and sarcopenia status were included in the cross-sectional analysis. A total of 7345 participants without multimorbidity from the CHARLS 2015 were included and followed up in 2018 in the longitudinal analysis. Logistic regression models were used in a cross-sectional investigation to assess the association between sarcopenia status and multimorbidity. In a longitudinal analysis, the relationships between sarcopenia status and multimorbidity were investigated using Cox proportional hazards models.

RESULTS

Multimorbidity was prevalent in the no sarcopenia, possible sarcopenia, and sarcopenia groups at 38.8 % (3765/9713), 56.6 % (1199/2118), and 48.5 % (451/929), respectively. Multivariable regression revealed that both possible sarcopenia (β = 0.088, P<0.001) and sarcopenia (β = 0.028, P = 0.009), contributed to the number of chronic diseases. Logistic regression revealed that possible sarcopenia (OR: 1.56, 95 % CI: 1.39-1.76) was associated with multimorbidity. In the longitudinal analysis, participants in the possible sarcopenia group (HR: 1.19, 95 % CI:1.03-1.38) were more prone to experience new onset multimorbidity than did participants in the no sarcopenia group.

CONCLUSIONS

Possible sarcopenia is associated with the development of multimorbidity in middle-aged and older Chinese populations. Health screening of populations with possible sarcopenia can facilitate early detection of multimorbidity.

Association of change in fat and lean mass with incident cardiovascular events for women in midlife and beyond: A prospective study using dual-energy x-ray absorptiometry (DXA)

OBJECTIVE

To determine whether changes in fat and lean mass over time, quantified using dual-energy x-ray absorptiometry (DXA), are related to incident cardiovascular events. Previous studies using surrogate anthropometric methods have had inconsistent findings.

STUDY DESIGN

Prospective, longitudinal observational study of women aged 40 to 80 randomly selected from the electoral roll and stratified into decades: 40-49, 50-59, 60-69 and 70-79 years.

MAIN OUTCOME MEASURES

Changes in anthropometric measurements (body mass index and waist-to-hip ratio) and DXA-quantified fat mass and lean mass between the first and fifth years of the study. Incident cardiovascular events recorded from the sixth to the 12th year.

RESULTS

In total 449 participants (87.9 %) were analyzed. A 10 % or greater decrease in total fat mass index was associated with a 67 % lower likelihood of any cardiovascular event (OR = 0.33, 95%CI 0.15-0.71); no association was observed for an increase. A 10 % or greater decrease in abdominal fat mass index was associated with a 62 % lower likelihood of incident stroke (OR = 0.38, 95%CI 0.16-0.91); no association was observed for an increase. A 10 % or greater decrease in appendicular lean mass index resulted in increased odds ratio of 2.91 for incident peripheral artery events (OR = 2.91, 95%CI 1.18-7.20).

CONCLUSIONS

Reducing fat mass for women in midlife and beyond may decrease the risk of cardiovascular events. An increase in fat mass may not contribute to additional cardiovascular events. A reduction in limb muscle mass may provide an independent marker for cardiometabolic risk and peripheral artery disease. No independent association was found using anthropometric measurements and incident cardiovascular events.

Impact of sarcopenia on early and mid-term outcomes of surgery for acute type A aortic dissection in octogenarians

OBJECTIVE

To determine the association between sarcopenia and surgical outcomes in octogenarians with acute type A aortic dissection.

METHODS

We enrolled 72 octogenarians who had undergone type A aortic dissection surgery between April 2013 and March 2019. The psoas muscle index, an indexed area of the psoas muscle at the L3 level on preoperative computed tomography, was obtained as an indicator of sarcopenia. The study participants were divided into sarcopenia and non-sarcopenia groups based on the mean psoas muscle index. The postoperative outcomes were compared between the groups.

RESULTS

The median age was 84 years (interquartile range 82-87 years), and 13 patients were male. The mean psoas muscle index was 3.53 ± 0.97 cm2/m2. Except for sex, no significant differences were observed in patients' baseline characteristics and operative data between the two groups. The 30-day mortality rates in the sarcopenia and non-sarcopenia groups were 14% and 8%, respectively (P = 0.71), and postoperative morbidity was similar in both groups. Postoperative all-cause mortality was significantly higher in the sarcopenia group (log-rank P = 0.038), especially in patients aged 85 years or older (log-rank P < 0.01). The sarcopenia group had a lower home discharge rate than the non-sarcopenia group (21% vs. 54%, P < 0.01), and home discharge was associated with longer survival (log-rank P = 0.015).

CONCLUSIONS

All-cause mortality after emergency surgery for acute type A aortic dissection was significantly higher in octogenarians with sarcopenia than in those without, especially in patients aged 85 years or older.

The relationship between skeletal muscle mass and the KOSHA cardiovascular risk in obese male workers

Background

Efforts for the prevention and management of cardiovascular diseases (CVDs) in workers have been actively pursued. Obesity is one of the important risk factors related to CVDs. Obesity has various metabolic characteristics, and some individuals can be metabolically healthy. Body composition including skeletal muscle mass is known to have protective effect in obesity. The study aims to investigate the association between skeletal muscle mass and Korea Occupational Safety and Health Agency (KOSHA) CVD risk among obese male manufacturing workers in Korea and to identify appropriate indicators of skeletal muscle mass for predicting risk of CVDs.

Methods

The study was conducted on 2,007 obese male workers at a manufacturing industry aged more than 19 years. Skeletal muscle mass, skeletal muscle index (SMI), skeletal muscle mass percent (SMM%) and skeletal muscle to body fat ratio (MFR) were used to evaluate body composition and these indicators were divided into quartiles. The odds ratios (ORs) and 95% confidence intervals (CIs) for the KOSHA CVD risk groups according to quartiles of skeletal muscle mass indicators were estimated using ordinal logistic regression analysis.

Results

The OR for the KOSHA CVD risk groups in the highest quartile of SMI was 1.67 (95% CI: 1.42-1.92), while the ORs for the KOSHA CVD risk groups in the highest quartiles of SMM%, SMM/body mass index (BMI), and MFR were 0.47 (95% CI: 0.22-0.72), 0.51 (95% CI: 0.05-0.76), and 0.48 (95% CI: 0.23-0.74), respectively.

Conclusions

We found that high SMI increase the likelihood of high risk of CVDs, while high SMM%, SMM/BMI, and MFR lower the likelihood of high risk of CVDs. Accurate evaluation of skeletal muscle mass can help assess the cardiovascular risk in obese male workers.

Acute Changes in Body Muscle Mass and Fat Depletion in Hospitalized Young Trauma Patients: A Descriptive Retrospective Study

Background: Loss of muscle mass, and its strength, is associated with adverse outcomes in many medical and surgical conditions. Trauma patients may get malnourished during their hospital course due to many interrelated contributing factors. However, there is insufficient knowledge on the acute muscle and fat changes in young trauma patients in the early days post-admission. Objective: to explore the diagnosis, feeding status, and outcome of muscle mass loss among young abdominal polytrauma patients. Methods: It was a retrospective study including hospitalized abdominal trauma patients who underwent an abdominal computerized tomographic (CT) examination initially and a follow-up one week later. CT scan-based automatic and manual analysis of the muscles and fat of the abdominal region was calculated and compared. Also, we evaluated the feeding and nutritional values to explore the adequacy of the provided calories and proteins and the potential influence of enteral feeding on the CT-based parameters for muscle loss and fat depletion. Results: There were 138 eligible subjects with a mean age of 32.8 ± 13.5 years; of them, 92% were males. Operative interventions were performed on two-thirds of the patients, including abdominal surgery (43%), orthopedic surgeries (34%), and neurosurgical procedures (8.1%). On admission, 56% received oral feeding, and this rate slightly increased to 58.4% after the first week. Enteral feed was prescribed for the remaining, except for two patients. The percentage of change in the total psoas muscle area was significantly reduced after one week of admission in patients on enteral feed as compared to those in the oral feeding group (p = 0.001). There were no statistically significant differences in the percentages of changes in the CT scan findings except for the total psoas muscle area (p = 0.001) and para-spinal muscle area (p = 0.02), which reduced significantly in the those who underwent laparotomy as compared to those who did not need laparotomy. Trauma patients who underwent emergency abdominal surgery lost muscle and fat over time. Conclusions: Loss of muscle mass and body fat is not uncommon among young trauma patients. Patients who underwent laparotomy are more likely to be affected. Further larger studies are needed to assess the specific features in the younger trauma population and how far this can be influenced by the nutrition status and its impact on the clinical outcomes. It could be early or impending stages of sarcopenia linked to trauma patients, or just acute changes in the muscle and fat, that need further investigation and follow-up after hospital discharge.

Management of Type 2 Diabetes in Frail Older Adults

Aging is one of the most important factors associated with the dramatic increase in the prevalence of type 2 diabetes mellitus (T2DM) globally. In addition to traditional micro- and macrovascular complications, diabetes mellitus (DM) in older adults is of great importance due to its independent relationship with frailty, which is defined as a decline in functional reserves and vulnerability to stressors. Frailty assessment enables the determination of biological age, thus predicting potential complications in older adults and identifying tailored treatment strategies. Although the latest guidelines have acknowledged the frailty concept and provided recommendations specific to this subgroup of older adults, frail older adults are particularly considered only as anorexic, malnourished people for whom relaxed treatment targets should be set. However, this approach bypasses other metabolic phenotypes in the context of diabetes and frailty. Recently, a spectrum of metabolic phenotypes in the context of frailty in DM was suggested, and the two edges of this spectrum were defined as "anorexic malnourished (AM)" and "sarcopenic obese (SO)." These two edges were suggested to require different strategies: Opposite to the AM phenotype requiring less stringent targets and de-intensification of treatments, tight blood glucose control with agents promoting weight loss was recommended in the SO group. Our suggestion is that, regardless of their phenotype, weight loss should not be the primary goal in DM management in older adults who are overweight or obese, because of the increased malnutrition prevalence in older adults suffering from DM compared with standard older adults. Furthermore, overweight older adults have been reported to have the lowest risk of mortality compared with other groups. On the other hand, obese older individuals may benefit from intensive lifestyle interventions including caloric restriction and regular exercise with the assurance of at least 1 g/kg/day high-quality protein intake. Besides metformin (MF), sodium-glucose cotransporter-2 inhibitors (SGLT-2i) or glucagon-like peptide-1 receptor agonists (GLP-1RA) should be considered in appropriate SO cases, due to high evidence of cardiorenal benefits. MF should be avoided in the AM phenotype due to their weight loss property. Although weight loss is not desired in AM phenotype, SGLT-2i may still be preferred with close follow-up in certain individuals demonstrating high cardiovascular disease (CVD) risk. Of note, SGLT-2i should be considered earlier in the diabetes treatment in both groups due to their multiple benefits, i.e., organ protective effects, the potential to reduce polypharmacy, and improve frailty status. The concept of different metabolic phenotypes in frail older adults with diabetes once again shows "one size fits all" cannot be applied in geriatric medicine, and a tailored, individualized approach should be adopted to get the highest benefit from treatments.

Intradialytic neuromuscular electrical stimulation with optional virtual reality distraction improves not only muscle strength and functional capacity but also serum albumin level in haemodialysis patients: a pilot randomized clinical trial

BACKGROUND

Sarcopenia is highly prevalent in haemodialysis (HD) patients and linked to a poor prognosis regarding comorbidities and premature mortality. Previous studies assessed the effects of neuromuscular electrical stimulation in haemodialysis patients. This study adds to the relevance of neuromuscular electrical stimulation (NMES) applications combined with a virtual reality (VR) distraction to increase intensity, dosage, and efficiency of NMES and slow sarcopenia progression in HD patients.

METHODS

We conducted a 12-week multicenter prospective randomised controlled trial. The patients were randomly assigned to one of the three groups: neuromuscular electrical stimulation with or without combined virtual reality distraction or control group.

RESULTS

The final analysis included 32 haemodialysis patients (mean age of 68 ± 10 years, 26 men). Interaction effects between groups and time (12 weeks) were significant regarding serum albumin levels (p = 0.008) and left quadriceps femoris muscle (QFM) force (p = 0.026). Both endpoints were increased in the NMES compared to the CO group at the end of the intervention. The NMES group increased serum albumin levels significantly after 12 weeks. The main effect of time was an increase in mean right QFM force between beginning and end of the intervention (p = 0.021). Functional capacity improved after 12 weeks in the NMES and NMES + VR but not in the control group, with a significant difference between the three groups (p = 0.022). Weight and body mass index increased in the NMES and NMES + VR groups, albeit not significantly. The effects of VR distraction on NMES efficiency were inconclusive.

CONCLUSION

Intradialytic NMES increases serum albumin level, functional capacity, muscle strength in lower limb and in tendency weight and body mass index of HD patients. Effects on VR distraction are inconclusive. Large-scaled follow-up studies on integrated sports programs with NMES and active training in combination with VR as distraction and motivation accelerator are needed.

TRIAL REGISTRATION

German Clinical Trial Register: DRKS00029276 (Retrospectively registered: 30/06/2022).

Repurposing Drugs for Diabetes Mellitus as Potential Pharmacological Treatments for Sarcopenia - A Narrative Review

Sarcopenia, the age-related loss of muscle strength and mass or quality, is a common condition with major adverse consequences. Although the pathophysiology is incompletely understood, there are common mechanisms between sarcopenia and the phenomenon of accelerated ageing seen in diabetes mellitus. Drugs currently used to treat type 2 diabetes mellitus may have mechanisms of action that are relevant to the prevention and treatment of sarcopenia, for those with type 2 diabetes and those without diabetes. This review summarises shared pathophysiology between sarcopenia and diabetes mellitus, including the effects of advanced glycation end products, mitochondrial dysfunction, chronic inflammation and changes to the insulin signalling pathway. Cellular and animal models have generated intriguing, albeit mixed, evidence that supports possible beneficial effects on skeletal muscle function for some classes of drugs used to treat diabetes, including metformin and SGLT2 inhibitors. Most human observational and intervention evidence for the effects of these drugs has been derived from populations with type 2 diabetes mellitus, and there is a need for intervention studies for older people with, and at risk of, sarcopenia to further investigate the balance of benefit and risk in these target populations. Not all diabetes treatments will be safe to use in those without diabetes because of variable side effects across classes. However, some agents [including glucagon-like peptide (GLP)-1 receptor agonists and SGLT2 inhibitors] have already demonstrated benefits in populations without diabetes, and it is these agents, along with metformin, that hold out the most promise for further investigation in sarcopenia.

Can Nutrition Contribute to a Reduction in Sarcopenia, Frailty, and Comorbidities in a Super-Aged Society?

Many countries are facing the advent of super-aging societies, where sarcopenia and frailty will become pertinent problems. The prevalence of comorbidities is a major problem in countries with aged populations as elderly people suffer from various diseases, such as diabetes, heart failure, chronic kidney disease and dementia. All of these diseases are associated with sarcopenia and frailty, and they frequently cause falls, fractures, and a decline in activities of daily living. Fractures in the elderly people are associated with bone fragility, which is influenced by diabetes and chronic kidney disease. Nutritional support for chronic disease patients and sarcopenic individuals with adequate energy and protein intake, vitamin D supplementation, blood glucose level management for individuals with diabetes, obesity prevention, nutritional education for healthy individuals, and the enlightenment of society could be crucial to solve the health-related problems in super-aging societies.

Early menopause and premature ovarian insufficiency may increase the risk of sarcopenia: A systematic review and meta-analysis

PURPOSE

Menopausal transition, resulting from a decline in estrogen concentrations, may compromise musculoskeletal health. However, it is unclear if early menopause (defined as age at menopause <45 years) and premature ovarian insufficiency (defined as age at menopause <40 years) are associated with increased risk of sarcopenia. The aim of this systematic review and meta-analysis was to synthesize studies evaluating the association between age at menopause and risk of sarcopenia.

METHODS

A comprehensive search was conducted in PubMed, CENTRAL and Scopus, up to 31 December 2022. Data were expressed as standardized mean difference with 95 % confidence intervals. The I² index was employed to evaluate heterogeneity.

RESULTS

Six studies were included in the qualitative and quantitative analysis, with a total of 18,291 post-menopausal women. Compared with women of normal age at menopause (>45 years), women with early menopause demonstrated lower muscle mass, assessed by appendicular skeletal muscle mass/body mass index [standardized mean difference (SMD) -0.14, 95 % confidence interval (CI) -0.20 to -0.07, p < 0.001; I² 0%]. However, no differences in muscle strength, assessed by handgrip strength (SMD -0.15, 95 % CI -0.31 to 0.01, p = 0.071; I² 72%), and muscle performance, assessed by gait speed (SMD -0.11, 95 % CI -0.29 to 0.05, p = 0.18; I² 79%), were found. Women with premature ovarian insufficiency had lower handgrip strength (SMD -0.3, 95 % CI -0.58 to -0.01, p = 0.04; I² 74.6 %) and gait speed (SMD -0.13, 95 % CI -0.23 to -0.04, p = 0.004; I² 0%) compared with women of normal age at menopause.

CONCLUSION

Early menopause is associated with reduced muscle mass and premature ovarian insufficiency with reduced muscle strength and performance compared with normal age at menopause.

Obesity and Aging

The obesity epidemic in aging populations poses significant public health concerns for greater morbidity and mortality risk. Age-related increased adiposity is multifactorial and often associated with reduced lean body mass. The criteria used to define obesity by body mass index in younger adults may not appropriately reflect age-related body composition changes. No consensus has been reached on the definition of sarcopenic obesity in older adults. Lifestyle interventions are generally recommended as initial therapy; however, these approaches have limitations in older adults. Similar benefits in older compared with younger adults are reported with pharmacotherapy, however, large randomized clinical trials in geriatric populations are lacking.

Differential effects of vitamin D on upper and lower body fat-free mass: potential mechanisms

Vitamin D insufficiency is a global health concern and low vitamin D status is regularly associated with reduced muscle mass and sarcopenia in observational research. Recent research using Mendelian randomization (MR) has highlighted the potentially causal positive effect of serum vitamin D (25(OH)D) on total, trunk and upper body appendicular fat-free mass (FFM). However, no such effect was found in lower body FFM, a result that mirrors the outcomes of some vitamin D intervention studies. Here we review the current literature on vitamin D, muscle mass and strength and discuss some potential mechanisms for the differing effects of vitamin D on upper and lower body FFM. In particular, differences in distribution of the vitamin D receptor as well as androgen receptors, in the upper and lower body musculature, will be discussed.

Assessing the Effects of Dietary Protein Supplementation on Sarcopenia in Community-Dwelling Older Adults

Sarcopenia, an age-associated skeletal muscle disorder characterized by muscle loss, is associated with disability in elderly populations. This literature review summarizes the impact of protein intake and supplementation on the indicators of severe sarcopenia-muscle mass, muscle strength, and physical function in community-dwelling older adults. We performed a literature search on PubMed, EMBASE, and MedLine, and included studies that evaluated the effects of protein intake with or without exercise intervention and on sarcopenia in community-dwelling older adults. Information regarding study participants, protein intervention, and sarcopenia-related outcomes were collected. Protein supplementation with or without exercise positively improves muscle mass, and aspects of muscle strength and physical function in sarcopenic and pre-frail older adults, while it elicited inconclusive effects in healthy populations. Greater dietary animal-based and soy-based protein diets can improve muscle mass in older adults. In conclusion, protein supplementation can improve muscle mass and reduce the risk of sarcopenia in sarcopenia and pre-frail older adults, while future studies should continue to investigate the effects of protein supplementation on indicators of sarcopenia in healthy older adults.

Ultrasound and magnetic resonance imaging as diagnostic tools for sarcopenia in immune-mediated rheumatic diseases (IMRDs)

Sarcopenia is characterized by loss of muscle mass, altered muscle composition, fat and fibrous tissue infiltration, and abnormal innervation, especially in older individuals with immune-mediated rheumatic diseases (IMRDs). Several techniques for measuring muscle mass, strength, and performance have emerged in recent decades. The portable dynamometer and gait speed represent the most frequently used tools for the evaluation of muscle strength and physical efficiency, respectively. Aside from dual-energy, X-ray, absorptiometry, and bioelectrical impedance analysis, ultrasound (US) and magnetic resonance imaging (MRI) techniques appear to have a potential role in evaluating muscle mass and composition. US and MRI have been shown to accurately identify sarcopenic biomarkers such as inflammation (edema), fatty infiltration (myosteatosis), alterations in muscle fibers, and muscular atrophy in patients with IMRDs. US is a low-cost, easy-to-use, and safe imaging method for assessing muscle mass, quality, architecture, and biomechanical function. This review summarizes the evidence for using US and MRI to assess sarcopenia.

Oculomics for sarcopenia prediction: a machine learning approach toward predictive, preventive, and personalized medicine

Aims

Sarcopenia is characterized by a gradual loss of skeletal muscle mass and strength with increased adverse outcomes. Recently, large-scale epidemiological studies have demonstrated a relationship between several chronic disorders and ocular pathological conditions using an oculomics approach. We hypothesized that sarcopenia can be predicted through eye examinations, without invasive tests or radiologic evaluations in the context of predictive, preventive, and personalized medicine (PPPM/3PM).

Methods

We analyzed data from the Korean National Health and Nutrition Examination Survey (KNHANES). The training set (80%, randomly selected from 2008 to 2010) data were used to construct the machine learning models. Internal (20%, randomly selected from 2008 to 2010) and external (from the KNHANES 2011) validation sets were used to assess the ability to predict sarcopenia. We included 8092 participants in the final dataset. Machine learning models (XGBoost) were trained on ophthalmological examinations and demographic factors to detect sarcopenia.

Results

In the exploratory analysis, decreased levator function (odds ratio [OR], 1.41; P value <0.001), cataracts (OR, 1.31; P value = 0.013), and age-related macular degeneration (OR, 1.38; P value = 0.026) were associated with an increased risk of sarcopenia in men. In women, an increased risk of sarcopenia was associated with blepharoptosis (OR, 1.23; P value = 0.038) and cataracts (OR, 1.29; P value = 0.010). The XGBoost technique showed areas under the receiver operating characteristic curves (AUCs) of 0.746 and 0.762 in men and women, respectively. The external validation achieved AUCs of 0.751 and 0.785 for men and women, respectively. For practical and fast hands-on experience with the predictive model for practitioners who may be willing to test the whole idea of sarcopenia prediction based on oculomics data, we developed a simple web-based calculator application (https://knhanesoculomics.github.io/sarcopenia) to predict the risk of sarcopenia and facilitate screening, based on the model established in this study.

Conclusion

Sarcopenia is treatable before the vicious cycle of sarcopenia-related deterioration begins. Therefore, early identification of individuals at a high risk of sarcopenia is essential in the context of PPPM. Our oculomics-based approach provides an effective strategy for sarcopenia prediction. The proposed method shows promise in significantly increasing the number of patients diagnosed with sarcopenia, potentially facilitating earlier intervention. Through patient oculometric monitoring, various pathological factors related to sarcopenia can be simultaneously analyzed, and doctors can provide personalized medical services according to each cause. Further studies are needed to confirm whether such a prediction algorithm can be used in real-world clinical settings to improve the diagnosis of sarcopenia.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-022-00292-3.

Comparison of various indices for predicting sarcopenia and its components in patients receiving peritoneal dialysis

This study aimed to evaluate and compare the usefulness of four indices-arm circumference, thigh circumference, mid-arm muscle circumference (MAMC), and thigh muscle circumference (TMC)-with that of other classical indicators of body composition in the prediction of sarcopenia and two sarcopenia-related components in patients receiving peritoneal dialysis (PD) grouped by sex. The data of all patients receiving PD who visited a tertiary medical center were collected (n = 214); of them 199 patients undergoing PD were included in the final analyses. Data on baseline characteristics and measurements, including circumferences of appendicular sites, handgrip strength (HGS), and appendicular lean mass (ALM) index, were obtained during a routine peritoneal membrane equilibration test. Body composition was evaluated using dual-energy X-ray absorptiometry. The ALM index (kg/m²) was defined as the sum of lean mass in the upper and lower extremities divided by height squared. Sarcopenia was defined as low HGS and low muscle mass based on the cut-off values in the Asian Working Group for Sarcopenia guideline. The circumferences of the lower extremities showed the greatest association with the ALM index in both sexes. Prediction of HGS was better with the MAMC than with the other indices in the male patients, whereas none of the indices were associated with HGS in the female patients. Moreover, the MAMC in the male patients and TMC in the female patients were the strongest predictors of sarcopenia among the six anthropometric indices. This study showed that the MAMC in male PD patients and TMC in female PD patients might be the best predictors of sarcopenia. However, the TMC was associated with sarcopenia regardless of HGS in the female PD patients. These findings suggest that, in PD patients, different indices should be considered in predicting sarcopenia or its components based on the sex.

Association between sarcopenia and osteoarthritis: A protocol for meta-analysis

Background

Sarcopenia, a relatively new syndrome referring to the age-related decline of muscle strength and degenerative loss of skeletal muscle mass and function, often resulting in frailty, disability, and mortality. Osteoarthritis, as a prevalent joint degenerative disease, is affecting over 250 million patients worldwide, and it is the fifth leading cause of disability. Despite the high prevalence of osteoarthritis, there are still lack of efficient treatment potions in clinics, partially due to the heterogeneous and complexity of osteoarthritis pathology. Previous studies revealed the association between sarcopenia and osteoarthritis, but the conclusions remain controversial and the prevalence of sarcopenia within osteoarthritis patients still needs to be elucidated. To identify the current evidence on the prevalence of sarcopenia and its association with osteoarthritis across studies, we performed this systematic review and meta-analysis that would help us to further confirm the association between these two diseases.

Methods and analysis

Electronic sources including PubMed, Embase, and Web of Science will be searched systematically following appropriate strategies to identify relevant studies from inception up to 28 February 2022 with no language restriction. Two investigators will evaluate the preselected studies independently for inclusion, data extraction and quality assessment using a standardized protocol. Meta-analysis will be performed to pool the estimated effect using studies assessing an association between sarcopenia and osteoarthritis. Subgroup analyses will also be performed when data are sufficient. Heterogeneity and publication bias of included studies will be investigated.

PROSPERO registration number

CRD42020155694.

Association of the triglyceride-glucose index with weight-adjusted appendicular lean mass in Chinese adolescents aged 12-18 years old

There is no study exploring the association between triglyceride-glucose (TyG) index and skeletal muscle mass in Chinese adolescents. Therefore, the objective of this study is to explore the association between TyG index and appendicular lean mass (ALM) in Chinese adolescents. In this study, 1336 adolescents (805 boys, 60.25%) aged 12-18 years in China were randomly selected through a stratified cluster sampling. According to the tertiles of TyG index, we separated all participants into three groups, and LM was measured by Bioelectrical Impedance Analysis. The TyG index was negatively related to ALM/weight in Chinese adolescents whether stratified by gender (boys: β = - 0.293; girls: β = - 0.195; all P < 0.001). After adjusting for age and BMI, a significant correlation between the TyG index and ALM/weight was observed only in boys (β = - 0.169, P = 0.001). The highest TyG index tertile was significantly associated with low ALM/weight after adjusting for all covariates in the full sample (OR = 3.04, 95% CI 1.12-8.26, P = 0.029) and boys (OR = 4.68, 95% CI 1.22-17.95, P = 0.025) only in overweight/obese group. Our findings suggested elevated levels of TyG index may be a risk factor of low ALM/weight in Chinese adolescents, especially in boys.

Clinical Impact of Sarcopenia on Cholangiocarcinoma

Sarcopenia is considered an important factor affecting the prognosis of cancer patients. Only complete surgical resection confers the chance of curing cholangiocarcinoma with sarcopenia. However, the prognosis is poor, even for patients who undergo surgical resection. Data from 13 trials of patients with sarcopenia and intrahepatic cholangiocarcinoma (ICC) or perihilar cholangiocarcinoma (PHC) were collected and reviewed. During all trials, sarcopenia was assessed using the psoas muscle or total skeletal muscle at the L3 level on cross-sectional images. The data showed heterogeneity among the subjects and treatment options and discrepancies in methods of measuring muscle mass and setting the cut-off level. Despite conflicting results regarding morbidity, mortality, and recurrence, sarcopenia may be associated with poor overall survival and recurrence-free survival (RFS) for ICC patients. The impact of sarcopenia on the morbidity of ICC patients remains unclear. The impact of PHC on morbidity, mortality, and RFS is also unclear. Further well-designed studies are needed to elucidate the effects of sarcopenia on ICC and PHC.

Sarcopenia increases the risk of major organ or vessel invasion in patients with papillary thyroid cancer

While sarcopenia is associated with poor overall survival and cancer-specific survival in solid cancer patients, the impact of sarcopenia on clinicopathologic features that can influence conventional papillary thyroid cancer (PTC) prognosis remains unclear. To investigate the impact of sarcopenia on aggressive clinicopathologic features in PTC patients, prospectively collected data on 305 patients who underwent surgery for PTC with preoperative staging ultrasonography and bioelectrical impedance analysis were retrospectively analyzed. Nine sarcopenia patients with preoperative sarcopenia showed more patients aged 55 or older (p = 0.022), higher male proportion (p < 0.001), lower body-mass index (p = 0.015), higher incidence of major organ or vessel invasion (p = 0.001), higher T stage (p = 0.002), higher TNM stage (p = 0.007), and more tumor recurrence (p = 0.023) compared to the non-sarcopenia patients. Unadjusted and adjusted logistic regression analyses showed that sarcopenia (odds ratio (OR) 9.936, 95% confidence interval (CI) 2.052–48.111, p = 0.004), tumor size (OR 1.048, 95% CI 1.005–1.093, p = 0.027), and tumor multiplicity (OR 3.323, 95% CI 1.048–10.534, p = 0.041) significantly increased the risk of T4 cancer. Sarcopenia patients showed significantly lower disease-free survival probability compared to non-sarcopenia patients. Therefore, preoperative sarcopenia in PTC patients should raise clinical suspicion for a more locally advanced disease and direct appropriate management and careful follow-up.

Protein interventions augment the effect of resistance exercise on appendicular lean mass and handgrip strength in older adults: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Increased protein intake is suggested as a strategy to slow or reverse the loss of muscle mass and strength observed in sarcopenia, but results from studies that directly tested this possibility have been inconsistent.

OBJECTIVES

We assessed the evidence on the effects of whole protein supplementation or higher-protein diets, without the use of amino acids or supplements known to stimulate hypertrophy, alone or in combination with resistance exercise (RE) interventions, on lean body mass (LBM) and strength in older adults.

METHODS

A systematic search was conducted using PubMed, Medline, Web of Science, and Cochrane CENTRAL databases from January 1990 to July 2021. Randomized controlled trials that assessed the effects of protein supplementation and/or higher-protein dietary interventions in older adults (mean age ≥50 y) on total LBM, appendicular lean mass (ALM), and handgrip (HG) and knee extension (KE) strength were included.

RESULTS

Twenty-eight studies were identified. In pooled analysis, compared with lower protein controls, protein supplementation did not have a significant positive effect on total LBM [weighted mean difference in change (WMD): 0.34; 95% CI: -0.21, 0.89; I2 = 90.01%], ALM (WMD: 0.4; 95% CI: -0.01, 0.81; I2 = 90.38%), HG strength (WMD: 0.69; 95% CI: -0.69, 2.06; I2 = 94.52%), or KE strength (WMD: 1.88; 95% CI: -0.6, 4.35; I2 = 95.35%). However, in interventions that used also RE, statistically significant positive effects of protein were observed for ALM (WMD: 0.54; 95% CI: 0.03, 1.05; I2 = 89.76%) and HG (WMD: 1.71; 95% CI: 0.12, 3.30; I2 = 88.71%). Meta-regression revealed no significant association between age, per-meal protein dose, duration, and baseline protein intake with change in any outcome. Subgroup analysis revealed the statistically significant effects on ALM occurred only in sarcopenic/frail populations (WMD: 0.88; 95% CI: 0.51, 1.25; I2 = 79.0%). Most studies (n = 22) had some risk of bias.

CONCLUSIONS

In older adults performing RE, increased protein intake leads to greater ALM and HG strength compared with lower protein controls. Without RE, protein has no additional benefit on changes in total LBM, ALM, or HG strength.

Older cancer patients receiving radiotherapy: a systematic review for the role of sarcopenia in treatment outcomes

BACKGROUND

Previous studies have evaluated the prognostic effects of sarcopenia in cancer patients receiving various treatments, including chemotherapy and surgery, but few studies have focused on radiotherapy (RT).

AIMS

We aimed to investigate the prevalence of sarcopenia and the relationship between sarcopenia and outcomes in older cancer patients who underwent RT without chemotherapy.

METHODS

A systematic review of the literature was conducted in Pubmed/Medline and Cochrane databases in September 2021. We used the search terms and medical subject heading terms "sarcopenia," "low muscle mass (LMM)," "low muscle strength," "LMM and low muscle strength," "LMM and low muscle strength and low physical performance," and "RT." Outcomes were overall survival (OS), progression-free survival, non-cancer death, cancer death, disease-specific survival, local failure-free survival, distant failure-free survival, and RT-related toxicities.

RESULTS

Among 460 studies, 8 studies were eligible for inclusion. The prevalence of sarcopenia was between 42.8% and 72%. Sarcopenia was not associated with OS or OS at 3 years in seven studies in which it was defined as the presence of LMM, while it was related in one study, in which it was defined as the concomitant presence of LMM and muscle strength/function.

DISCUSSION

There was heterogeneity between the studies because there was diversity in their inclusion criteria, definition and assessment methods used for detection of sarcopenia, considered cutoffs for low muscle mass and strength, cross-sectional locations on imaging to assess muscle mass and included covariates. The discrepancy in the results of the studies may also result from the variations in diagnoses, sample sizes, and treatment modalities. The low number of included studies and a small number of patients in each study limited generalizability.

CONCLUSIONS

Sarcopenia may be a prognostic factor, especially in OS when low muscle strength/function is integrated into its definition. We suggest that clinicians focus on muscle strength/function while considering sarcopenia and its association with cancer and RT-related outcomes.

Cutoff Points for Grip Strength in Screening for Sarcopenia in Community-Dwelling Older-Adults: A Systematic Review

BACKGROUND

Currently, different cutoff points for handgrip strength (HGS) have been used to estimate the prevalence of sarcopenia. In addition, the variability of equipment and protocols for this assessment can significantly influence the early detection of this important public health problem. Thus, this review aims to identify the different cutoff points for HGS adopted for older men and women in screening for sarcopenia.

OBJECTIVES

this review aims to identify the different cutoff points for HGS adopted for older men and women in screening for sarcopenia.

METHODS

In accordance with the PRISMA 2020 recommendations, which included published studies from the last 10 years, from 6 databases, in 3 different languages.

RESULTS

19.730 references were identified, of which 62 were included for the review. All references analyzed used algorithms and definitions of sarcopenia already known in the literature. Of the studies found, 16 chose to develop cutoff values for HGS based on their own population. The variation in cutoff points was evident when compared between gender and regions of the world.

CONCLUSION

It has become evident that there is a variability of normative values for HGS in sarcopenia screening. In addition, this systematic review shows the difference in the cutoff points used between the consensuses and those developed for each population.

Genetically Determined Serum 25-Hydroxyvitamin D Is Associated with Total, Trunk, and Arm Fat-Free Mass: A Mendelian Randomization Study

PURPOSE

Low serum vitamin D status has been associated with reduced muscle mass in observational studies although the relationship is controversial and a causal association cannot be determined from such observations. Two-sample Mendelian randomization (MR) was applied to assess the association between serum vitamin D (25(OH)D) and total, trunk, arm and leg fat-free mass (FFM).

METHODS

MR was implemented using summary-level data from the largest genome-wide association studies (GWAS) on vitamin D (n=73,699) and total, trunk, arm and leg FFM. Inverse variance weighted method (IVW) was used to estimate the causal estimates. Weighted median (WM)-based method, and MR-Egger, leave-one-out were applied as sensitivity analysis.

RESULTS

Genetically higher serum 25(OH)D levels had a positive effect on total (IVW = Beta: 0.042, p = 0.038), trunk (IVW = Beta: 0.045, p = 0.023) and arm (right arm IVW = Beta: 0.044, p = 0.002; left arm IVW = Beta: 0.05, p = 0.005) FFM. However, the association with leg FFM was not significant (right leg IVW = Beta: 0.03, p = 0.238; left leg IVW = Beta: 0.039, p = 0.100). The likelihood of heterogeneity and pleiotropy was determined to be low (statistically non-significant), and the observed associations were not driven by single SNPs. Furthermore, MR pleiotropy residual sum and outlier test did not highlight any outliers.

CONCLUSIONS

Our results illustrate the potentially causal, positive effect of serum 25(OH)D concentration on total, trunk and upper body appendicular fat-free mass.

Lower Limb Muscle Strength and Muscle Mass Are Associated With Incident Symptomatic Knee Osteoarthritis: A Longitudinal Cohort Study

Recent literature suggests that sarcopenia, often represented by low lower limbs muscle mass and strength, can be considered a potential risk factor for knee osteoarthritis (OA), but the available literature is still limited. We therefore aimed to investigate whether sarcopenia is associated with a higher risk of radiographic (ROA) and symptomatic knee OA (SxOA) in a large cohort of North American people in the context of the OA initiative. Sarcopenia at baseline was diagnosed in case of low skeletal muscle mass (i.e., lower skeletal mass index) and poor performance in the chair stands test. The outcomes of interest for this study included ROA (radiographical osteoarthritis) if a knee developed a Kellgren and Lawrence (KL) grade ≥2 at follow-up, and SxOA (symptomatic osteoarthritis) defined as new onset of a combination of painful knee OA. Altogether, 2,492 older participants (mean age: 68.4 years, 61.4% females) were included. At baseline, sarcopenia was present in 6.1% of the population. No significant difference in ROA prevalence was observed between those with and without sarcopenia (p=0.76), whilst people with sarcopenia reported a significant higher prevalence of SxOA (p<0.0001). Using a logistic regression analysis, adjusting for potential confounders at baseline and the diagnosis of sarcopenia during follow-up, sarcopenia was associated with a higher incidence of knee SxOA (odds ratio, OR=2.29; 95%CI [confidence interval]: 1.42-3.71; p=0.001), but not knee ROA (OR=1.48; 95%CI: 0.53-4.10; p=0.45). In conclusion, sarcopenia could be associated with a higher risk of negative knee OA outcomes, in particular symptomatic forms.

Associations between homocysteine, inflammatory cytokines and sarcopenia in Chinese older adults with type 2 diabetes

Background

Sarcopenia, an age-related disease, has been implicated as both a cause and consequence of type 2 diabetes mellitus (T2DM) and a symbol of poor prognosis in older adults with T2DM. Therefore, early detection and effective treatment of sarcopenia are particularly important in older adults with T2DM. We aimed to investigate the prevalence of sarcopenia in Chinese older T2DM patients and explore whether homocysteine and inflammatory indexes could serve as biomarkers and participate in the development process of sarcopenia.

Methods

T2DM patients aged over 60 years were consecutively recruited from the ward of department of Endocrinology, Xuanwu Hospital between April 2017 and April 2019. Sarcopenia was defined based on the standard of the Asian Working Group of Sarcopenia, including muscle mass, grip strength and gait speed. Logistic regression was used to explore the association between biochemical indicators and sarcopenia. Receiver operating characteristic (ROC) curves were applied to determine the diagnostic effect of these clinical indicators.

Results

Totally 582 older adults with T2DM were characterized and analyzed in the study. Approximately 8.9% of the older T2DM patients had sarcopenia. After adjusting for age, sex, body mass index (BMI) and hemoglobin A1c (HbA1c), increased concentrations of homocysteine [odds ratio (OR): 2.829; 95% confidence interval (CI), 1.064–7.525] and high-sensitive C-reactive protein (hs-CRP) (OR: 1.021; 95% CI, 1.001–1.042) were independent predictors of sarcopenia; but not interleukin-6. The combination of age, sex, BMI and HbA1c provided a discriminatory effect of sarcopenia with an area under the curve (AUC) of 0.856, when homocysteine was added to the model, the value of the ROC curve was further improved, with an AUC of 0.861.

Conclusion

In the current study, we demonstrated a positive correlation of homocysteine, hs-CRP with sarcopenia in older adults with T2DM and the relationship remained significant even after adjustment for HbA1c. These biomarkers (homocysteine and hs-CRP) may play important roles in the pathological process of sarcopenia.

Effects of resistance exercise and whey protein supplementation on skeletal muscle strength, mass, physical function, and hormonal and inflammatory biomarkers in healthy active older men: a randomised, double-blind, placebo-controlled trial

PURPOSE

To determine the individual and combined effects of 12 weeks of resistance exercise (RE) and whey protein supplementation on skeletal muscle strength (primary outcome), mass and physical function, and hormonal and inflammatory biomarkers in older adults.

METHODS

Thirty-six healthy older men [(mean±SE) age: 67±1 y; BMI: 25.5±0.4 kg/m²] were randomised to either control (CON; n=9), whey protein (PRO; n=9), RE+control (EX+CON; n=9), or RE+whey protein (EX+PRO; n=9) in a double-blinded fashion. Whole-body RE (2 sets of 8 repetitions and 1 set to volitional failure at 80% 1RM) was performed twice weekly. Supplements (PRO, 25 g whey protein isolate; CON, 23.75 g maltodextrin) were consumed twice daily.

RESULTS

EX+CON and EX+PRO increased leg extension (+19±3 kg and +20±3 kg, respectively) and leg press 1RM (+27±3 kg and +39±2 kg, respectively) greater than the CON and PRO groups (P<0.001, Cohen's d=1.50-1.90). RE (EX+CON and EX+PRO groups pooled) also increased fat-free mass (FFM) (+0.9±0.3 kg) and 6-min walk test distance (+21±5 m) and decreased fat mass (-0.4±0.4 kg), and interleukin-6 (-1.0±0.4 pg/mL) and tumor necrosis factor-alpha concentration (-0.7±0.3 pg/mL) greater than non-exercise (CON and PRO groups pooled; P<0.05, Cohen's f=0.37-0.45). Whey protein supplementation (PRO and EX+PRO groups pooled) increased 4-m gait speed greater than control (CON and EX+CON groups pooled) (+0.08±0.03 m/s; P=0.007, f=0.51).

CONCLUSION

RE increased muscle strength, FFM and physical function, and decreased markers of systemic inflammation in healthy active older men. Whey protein supplementation alone increased gait speed. No synergistic effects were observed. This study was registered at clinicaltrials.gov as NCT03299972.

Adverse muscle composition predicts all-cause mortality in the UK Biobank imaging study

BACKGROUND

Adverse muscle composition (MC) as measured by magnetic resonance imaging has previously been linked to poor function, comorbidity, and increased hospitalization. The aim of this study was to investigate if adverse MC predicts all-cause mortality using data from UK Biobank.

METHODS

There were 40 178 participants scanned using a 6 min magnetic resonance imaging protocol. Images were analysed for thigh fat-tissue free muscle volume and muscle fat infiltration (MFI) using AMRA® Researcher (AMRA Medical, Linköping, Sweden). For each participant, a sex, weight, and height invariant muscle volume z-score was calculated. Participants were partitioned into four MC groups: (i) normal MC, (ii) only low muscle volume [<25th percentile for muscle volume z-score (population wide)], (iii) only high MFI [>75th percentile (population wide, sex-specific)], and (iv) adverse MC (low muscle volume z-score and high MFI). Association of MC groups with mortality was investigated using Cox proportional-hazard modelling with normal MC as referent (unadjusted and adjusted for low hand grip strength, sex, age, body mass index, previous diagnosis of disease (cancer, type 2 diabetes and coronary heart disease), lifestyle, and socioeconomic factors (smoking, alcohol consumption, physical activity, and Townsend deprivation index).

RESULTS

Muscle composition measurements were complete for 39 804 participants [52% female, mean (SD) age 64.2 (7.6) years and body mass index 26.4 (4.4) kg/m² ]. Three hundred twenty-eight deaths were recorded during a follow-up period of 2.9 (1.4) years after imaging. At imaging, adverse MC was detected in 10.5% of participants. The risk of death from any cause in adverse MC compared with normal MC was 3.71 (95% confidence interval 2.81-4.91, P < 0.001). Only low muscle volume and only high MFI were independently associated with all-cause mortality [1.58 (1.13-2.21), P = 0.007, and 2.02 (1.51-2.71), P < 0.001, respectively]. Adjustment of low hand grip strength [1.77 (1.28-2.44), P < 0.001] did not attenuate the associations with any of the MC groups. In the fully adjusted model, adverse MC and only high MFI remained significant (P < 0.001 and P = 0.020) while the association with only low muscle volume was attenuated to non-significance (P = 0.560). The predictive performance of adverse MC [1.96 (1.42-2.71), P < 0.001] was comparable with that of previous cancer diagnosis [1.93 (1.47-2.53), P < 0.001] and smoking [1.71 (1.02-2.84), P = 0.040]. Low hand grip strength was borderline non-significant [1.34 (0.96-1.88), P = 0.090].

CONCLUSIONS

Adverse MC was a strong and independent predictor of all-cause mortality. Sarcopenia guidelines can be strengthened by including cut-offs for myosteatosis enabling detection of adverse MC.

Sarcopenia risk and associated factors among Chinese community-dwelling older adults living alone

Sarcopenia, defined as a progressive loss of muscle mass and reduced muscle strength and functional capacity, is common among older adults. This study aimed to assess the proportion of people at risk of sarcopenia and probable sarcopenia among Chinese community-dwelling older adults living alone and to identify the associated factors. A total of 390 older adults were included in this study. Sarcopenia and probable sarcopenia were defined according to the criteria of the Asian Working Group for Sarcopenia 2019. Data on socio-demographic characteristics, health status, health behaviours and lifestyle characteristics, nutritional status, physical activity level, and depressive symptoms were collected. The association between these characteristics and sarcopenia risk was analysed using a multivariate ordinal logistic regression. The proportion of subjects at risk of sarcopenia and probable sarcopenia was found to be 57.7% and 30%, respectively. Older age, being malnourished and being at risk of malnutrition were significantly associated with sarcopenia risk. Being educated to secondary level or above, being overweight or obese and higher physical activity level were associated with decreased sarcopenia risk. Our results showed that older adults living alone were at high risk of developing sarcopenia and probable sarcopenia. These results emphasise the urgent need to initiate aggressive screening and holistic lifestyle therapeutic intervention strategies for this high-risk population.

A simpler screening tool for sarcopenia in surgical patients

BACKGROUND

Sarcopenia is defined as decreased skeletal muscle mass and muscle functions (strength and physical performance). Muscle mass is measured by specific methods, such as bioelectrical impedance analysis and dual-energy X-ray absorptiometry. However, the devices used for these methods are costly and are usually not portable. A simple tool to screen for sarcopenia without measuring muscle mass might be practical, especially in developing countries. The aim of this study was to design a simple screening tool and to validate its performance in screening for sarcopenia in older adult cancer patients scheduled for elective surgery.

METHODS

Cancer surgical patients aged >60 years were enrolled. Their nutritional statuses were evaluated using the Mini Nutrition Assessment-Short Form. Sarcopenia was assessed using Asian Working Group for Sarcopenia (AWGS) criteria. Appendicular skeletal muscle mass was measured by bioelectrical impedance analysis. Four screening formulas with differing combinations of factors (muscle strength, physical performance, and nutritional status) were assessed. The validities of the formulas, compared with the AWGS definition, are presented as sensitivity, specificity, accuracy, and area under a receiver operating characteristic curve.

RESULTS

Of 251 enrolled surgical patients, 84 (34%) were diagnosed with sarcopenia. Malnutrition (odds ratio [OR]: 2.89, 95% CI: 1.40-5.93); underweight status (OR: 2.80, 95% CI: 1.06-7.43); and age increments of 5 years (OR: 1.78, 95% CI: 1.41-2.24) were independent predictors of preoperative sarcopenia. The combination of low muscle strength and/or abnormal physical performance, plus malnutrition/risk of malnutrition had the highest sensitivity, specificity, and accuracy (81.0%, 78.4%, and 79.3%, respectively). This screening formula estimated the probability of sarcopenia with a positive predictive value of 65.4% and a negative predictive value of 89.1%.

CONCLUSION

Sarcopenia screening can be performed using a simple tool. The combination of low muscle strength and/or abnormal physical performance, plus malnutrition/risk of malnutrition, has the highest screening performance.

Sarcopenia modifies the associations of nonalcoholic fatty liver disease with all-cause and cardiovascular mortality among older adults

The contribution of nonalcoholic fatty liver disease (NAFLD) to all-cause and cardiovascular mortality remains controversial. Sarcopenia, a measure of muscle mass, strength and function, may identify which persons are most at risk for adverse effects of NAFLD. We aimed to test the hypothesis that sarcopenia modifies the associations between NAFLD and all-cause and cardiovascular mortality. A total of 2446 older adults (≥ 60 years) from the third National Health and Nutrition Examination Survey were enrolled. Their mortality data were linked to death certificates in the National Death Index. Sarcopenia was defined as having low skeletal muscle mass together with slow gait speed, which captures both muscle mass and muscle function. Ultrasound tests were used for the assessment of hepatic steatosis. During follow-up (median 16.8 years), 1530 older subjects died from any cause, of which 379 were cardiovascular-related. All-cause and cardiovascular mortality rates were 4.31 and 1.07 per 100 person-years, respectively. In a multivariate model, using participants without NAFLD and sarcopenia as the reference group, individuals with both NAFLD and sarcopenia had 1.69 times [95% confidence interval (CI) 1.23-2.31] and 2.17 times (95% CI 1.33-3.54) higher risks of all-cause and cardiovascular mortality, respectively. However, NAFLD persons without sarcopenia had hazard ratios for all-cause and cardiovascular mortality similar to those of the reference group. Sarcopenia modified the associations of NAFLD with all-cause and cardiovascular mortality. Sarcopenia may identify older adults who are at the highest risk for adverse outcomes associated with NAFLD.

Long-Term Outcomes After In-Hospital Cardiac Arrest: Does Pre-arrest Skeletal Muscle Depletion Matter?

Background: Skeletal muscle depletion is prevalent in elderly patients and is associated with unfavorable outcomes in patients with chronic diseases. However, the relationship between skeletal muscle mass and neurological outcomes following in-hospital cardiac arrest (IHCA) has not been evaluated. The aim of this study was to investigate whether skeletal muscle status before cardiac arrest is an independent factor affecting neurological outcomes in patients with IHCA. Methods: We reviewed a prospectively enrolled registry of IHCA patients. Consecutive adult patients (>18 years) admitted to a tertiary care hospital from 2013 to 2019 were included in the study. Of these, 421 patients who underwent abdominopelvic computed tomography within 3 months of cardiac arrest were included. Skeletal muscle index (SMI) was measured at the third lumbar vertebra, and skeletal muscle depletion was defined using sex- and body mass index-specific cutoffs of SMI. The primary outcome was a Cerebral Performance Category score of 1 or 2 at 6 months after cardiac arrest, which was considered a good neurological outcome. Results: Of the 421 patients, 248 (58.9%) had skeletal muscle depletion before IHCA. The patients without skeletal muscle depletion showed significantly better neurological outcomes at 6 months after cardiac arrest than those with pre-arrest muscle depletion (20.8 vs. 10.9%, p = 0.004). The absence of skeletal muscle depletion was significantly associated with good neurological outcomes in a multivariable logistic analysis (OR = 3.49, 95% confidence intervals: 1.83-6.65, p < 0.001), along with the absence of diabetes, presence of active cancer, shockable rhythm, and short resuscitation duration. Conclusion: Pre-arrest skeletal muscle depletion was associated with long-term mortality and poor neurological outcomes after IHCA. Skeletal muscle depletion may be used as a tool to identify at-risk patients who may benefit from aggressive treatments.

Fibrinogen, fibrin degradation products and risk of sarcopenia

BACKGROUND & AIMS

Increasing data suggests that chronic low-grade inflammation plays an important role on development of sarcopenia. The present study was designed to identify the association between fibrinogen, fibrin degradation products (FDP) and sarcopenia risk in hospitalized old patients.

METHODS

A total of 437 patients were enrolled in this cross-sectional study (148 with sarcopenia and 289 without sarcopenia). Sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia (AWGS) 2019 criteria. Body composition, grip strength and gait speed were performed to participants. Fibrinogen, FDP levels were measured. Logistic regression analyses were carried out to assess the association between fibrinogen and sarcopenia, between FDP and sarcopenia, respectively.

RESULTS

Compared to non-sarcopenic patients, fibrinogen and FDP levels were found to be higher in the sarcopenic group (3.07 g/L vs 2.79 g/L, 1.75 μg/mL vs 1.00 μg/mL, respectively, p < 0.05). Multiple linear regression analysis showed a significant negative association between fibrinogen and gait speed (β: -0.164, p = 0.008), and muscle strength (β: -0.231, p < 0.001). Multivariable logistic regression analysis showed that fibrinogen and FDP were independently associated with sarcopenia (odds ratio 1.32 [95% confidence interval 1.03, 1.70], p = 0.009; odds ratio 1.07 [95% confidence interval 1.01, 1.19], p = 0.049, respectively). ROC curve revealed that the cutoff values of fibrinogen and FDP to predict sarcopenia risk were 2.54 g/L and 1.15 μg/mL, respectively.

CONCLUSIONS

In hospitalized old patients, serum fibrinogen and FDP levels are elevated in sarcopenia patients than those without sarcopenia. Fibrinogen and FDP are associated with sarcopenia in a concentration-dependent manner.

Resistance Exercise, Aging, Disuse, and Muscle Protein Metabolism

Skeletal muscle is the organ of locomotion, its optimal function is critical for athletic performance, and is also important for health due to its contribution to resting metabolic rate and as a site for glucose uptake and storage. Numerous endogenous and exogenous factors influence muscle mass. Much of what is currently known regarding muscle protein turnover is owed to the development and use of stable isotope tracers. Skeletal muscle mass is determined by the meal- and contraction-induced alterations of muscle protein synthesis and muscle protein breakdown. Increased loading as resistance training is the most potent nonpharmacological strategy by which skeletal muscle mass can be increased. Conversely, aging (sarcopenia) and muscle disuse lead to the development of anabolic resistance and contribute to the loss of skeletal muscle mass. Nascent omics-based technologies have significantly improved our understanding surrounding the regulation of skeletal muscle mass at the gene, transcript, and protein levels. Despite significant advances surrounding the mechanistic intricacies that underpin changes in skeletal muscle mass, these processes are complex, and more work is certainly needed. In this article, we provide an overview of the importance of skeletal muscle, describe the influence that resistance training, aging, and disuse exert on muscle protein turnover and the molecular regulatory processes that contribute to changes in muscle protein abundance. © 2021 American Physiological Society. Compr Physiol 11:2249-2278, 2021.

Fatores associados à Sarcopenia em idosos da comunidade

RESUMO O objetivo deste estudo foi identificar os fatores associados à sarcopenia em idosos da comunidade. Tratou-se de um estudo correlacional, de corte transversal e abordagem quantitativa, realizado com 234 idosos da comunidade. Para avaliar a sarcopenia foram utilizados os critérios do European working group on sarcopenia in older people (EWGSOP2) e para coleta de dados foram utilizados: questionário sociodemográfico e de saúde para caracterização dos idosos; escala de depressão geriátrica, Addenbrooke’s cognitive examination-revised, international physical activity questionnaire, versão longa e o medical outcomes study 36-item short-form health survey. Houve predominância de pessoas do sexo feminino (n=151; 68,30%), de cor branca (n=163; 73,80%), com sobrepeso, segundo o Índice de Massa Corporal (IMC) (n=124; 56,10%) e 24,90% (n=55) dos participantes apresentaram sarcopenia, segundo os critérios do consenso europeu. Se associaram à sarcopenia os seguintes fatores: idade (OR=1,06; p=0,010), IMC<22kg/m2(OR=5,82; p=0,003), ser insuficientemente ativo fisicamente (OR=3,29; p=0,002) e presença de quedas (OR=2,20; p=0,033). Os idosos com idade avançada, com baixo peso, insuficientemente ativos fisicamente e que sofreram quedas têm mais chance de apresentar sarcopenia.

Skeletal Muscle and Childhood Cancer: Where are we now and where we go from here

Skeletal muscle (muscle) is essential for physical health and for metabolic integrity, with sarcopenia (progressive muscle mass loss and weakness), a pre-curser of aging and chronic disease. Loss of lean mass and muscle quality (force generation per unit of muscle) in the general population are associated with fatigue, weakness, and slowed walking speed, eventually interfering with the ability to maintain physical independence, and impacting participation in social roles and quality of life. Muscle mass and strength impairments are also documented during childhood cancer treatment, which often persist into adult survivorship, and contribute to an aging phenotype in this vulnerable population. Although several treatment exposures appear to confer increased risk for loss of mass and strength that persists after therapy, the pathophysiology responsible for poor muscle quantity and quality is not well understood in the childhood cancer survivor population. This is partly due to limited access to both pediatric and adult survivor muscle tissue samples, and to difficulties surrounding non-invasive investigative approaches for muscle assessment. Because muscle accounts for just under half of the body's mass, and is essential for movement, metabolism and metabolic health, understanding mechanisms of injury responsible for both initial and persistent dysfunction is important, and will provide a foundation for intervention. The purpose of this review is to provide an overview of the available evidence describing associations between childhood cancer, its treatment, and muscle outcomes, identifying gaps in current knowledge.

Functional autonomy and sarcopenia markers in women over 55 years of age

Introduction: Some parameters used to diagnose sarcopenia and functional autonomy disorders can lead to interpretation and classification errors. Objective: To analyze sarcopenia markers and their relationship with the strength and gait of physically active older women aged between 55 and 76 years. Materials and Methods: Analytical observational study conducted in 178 physically active Colombian women who were distributed in two age groups (group 1: 55-66 years, n=98, and group 2: 67-76 years, n=80). A multiple linear regression model was used to establish possible correlations between strength and gait indicators (dependent variables) and body composition (independent variables). Results: Fat mass and appendicular mass (appendicular lean/height2(kg/m2)) explained power variance in the lower limbs in group 1 (G1) (SJ: p=0.001, R2=0.56; CMJ: p=0.001, R2=0.51; CMJAS: R2=0.60, p=0.001). Similar results were observed in group 2 (G2) (SJ: R2=0.32, DW1=2.14; CMJ: R2=0.51, DW2=2.38; CMJAS: R2=0.41, DW3=2.56). Furthermore, fat mass explained variance in gait pattern in G1 and G2 differently (G1: p=-0.006; R2=20%; G2: p=-0.001; R2=29%). Conclusion: Recording fat and appendicular mass allow studying negative changes in lower limb strength and their effect on gait pattern, as well as identifying the type of sarcopenia and functional autonomy disorders in physically active Colombian women aged 55 to 76 years.