An evidence-based comparison of operational criteria for the presence of sarcopenia

Association between triglyceride-glucose index and sarcopenia in patients with chronic inflammatory airway disease

Objective

This research sought to explore the association between the triglyceride-glucose (TyG) index and the risk of sarcopenia in patients with chronic inflammatory airway disease (CIAD).

Methods

Data were obtained from the National Health and Nutrition Examination Survey 2011-2018. Grouping was performed using TyG index tertiles and multiple logistic regression was employed to assess the correlation between TyG levels and the risk of sarcopenia. The Receiver Operating Characteristic (ROC) curve analysis was conducted to determine the prognostic value of the TyG index for sarcopenia. Linear regression analysis was utilized to elucidate the direct relationship between TyG index and sarcopenia. Additionally, the curve between the TyG and sarcopenia indices was examined using a generalized additive model.

Results

The study included 981 individuals diagnosed with CIAD. After adjusting for potential confounders, a significant positive correlation was observed between TyG and sarcopenia (OR = 1.70, 95 % CI: 1.20-2.39, P = 0.002). Trend analysis using the chi-square test revealed an increase in sarcopenia prevalence concomitant with higher TyG levels (P < 0.05). Furthermore, linear regression analysis revealed a notable inverse linear association between the TyG and sarcopenia indices (β = -0.03; 95 % CI: -0.07-0.01; P = 0.020). The ROC curves corroborated the robust predictive capacity of TyG for sarcopenia among patients with CIAD, with an AUC of 0.685 (95 % CI: 0.636-0.735, P < 0.001).

Conclusion

Our research indicates a positive association between TyG and sarcopenia in CIAD patients. The TyG index may serve as a reliable marker for predicting sarcopenia risk in CIAD patients.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Investigating the effects of synbiotic supplementation on functional movement, strength and muscle health in older Australians: a study protocol for a double-blind, randomized, placebo-controlled trial

BACKGROUND

Aging has been associated with a progressive loss of skeletal muscle quality, quantity and strength, which may result in a condition known as sarcopenia, leading to a decline in physical performance, loss of independence and reduced quality of life. While the cause of impaired physical functioning observed in elderly populations appears to be multifactorial, recent evidence suggests that age-associated alterations in gut microbiota could be a contributing factor. The primary objective will be to assess the effects of a dietary synbiotic formulation on sarcopenia-related functional outcomes such as handgrip strength, gait speed and physical performance within older individuals living independently. The secondary objective will be to examine associations between changes in gut microbiota composition, functional performance and lean muscle mass.

METHODS

Seventy-four elderly (60-85 years) participants will be randomized in a double-blind, placebo-controlled fashion to either an intervention or control group. The intervention group (n = 37) will receive oral synbiotic formulation daily for 16 weeks. The control group (n = 37) will receive placebo. Assessments of physical performance (including Short Physical Performance Battery, handgrip strength and timed up-and-go tests) and muscle ultrasonography will be performed at 4 time points (baseline and weeks 8, 16 and 20). Likewise, body composition via bioelectric impedance analysis and blood and stool samples will be collected at each time point. Dual-energy X-ray absorptiometry will be performed at baseline and week 16. The primary outcomes will be between-group changes in physical performance from baseline to 16 weeks. Secondary outcomes include changes in body composition, muscle mass and architecture, fecal microbiota composition and diversity, and fecal and plasma metabolomics.

DISCUSSION

Gut-modulating supplements appear to be effective in modifying gut microbiota composition in healthy older adults. However, it is unclear whether these changes translate into functional and/or health improvements. In the present study, we will investigate the effects of a synbiotic formulation on measures of physical performance, strength and muscle health in healthy older populations.

TRIAL REGISTRATION

This study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000652774) in May 2022.

Evolving concepts on perioperative nutrition of sarcopenic cancer patients

The recent recognition of the association of sarcopenia with an increased risk of complications after a surgical procedure calls for rethinking the proper approach of the perioperative care in cancer patients. Sarcopenia is broadly considered in literature according to three different definitions: loss of muscle mass, loss of muscle mass plus reduced muscle function and myosteatosis. The aim of this short review on this issue is to define the excess of risk by type of primary and of surgical procedure, depending on the definition of sarcopenia, to speculate on this association (casual versus causal) and to examine the current therapeutical approaches. The analysis of the data shows that sarcopenia, defined as loss of muscle mass plus reduced muscle function, has the higher predictive power for the occurrence of postoperative complications than the two other definitions, and any definition of sarcopenia works better than the usual indexes or scores of surgical risk. Our analysis supports the concept that: a) sarcopenia is frequently associated with inflammation, but inflammation cannot be considered the only or the absolute cause for sarcopenia, b) sarcopenia is not a simple marker of risk but can have a direct role in the increase of risk. Data on perioperative care of sarcopenic cancer patients are scanty but a correct approach cannot rely on nutritional support alone but on a combined approach of optimized nutrition and exercise, hopefully associated with an anti-inflammatory treatment. This strategy should be applied proactively in keeping with the recent recommendations of the American Society of Clinical Oncology for the medical treatment of advanced cancer patients even if a clear demonstration of effectiveness is still lacking.

Different Diagnostic Criteria for Determining the Prevalence of Sarcopenia in Older Adults: A Systematic Review

Background: Sarcopenia is defined as a loss of muscle mass, strength, and physical function associated with aging. It is due to a combination of genetic, environmental, and physiological factors. It is also associated with an increased risk of health problems. Since there are many different researchers in the field, with their own algorithms and cut-off points, there is no single criterion for diagnosis. This review aims to compare the prevalence of sarcopenia according to these different diagnostic criteria in older adult populations by age group and sex. Methods: Different databases were searched: Web of Science, Pubmed, Dialnet, Scopus, and Cochrane. The keywords used were "sarcopenia", "diagnosis", "prevalence", "assessment", "aged", "aging" and "older". Studies conducted in a population aged ≥65 assessing the prevalence of sarcopenia were selected. Results: Nineteen articles met the inclusion criteria, with a total of 33,515 subjects, 38.08% female and 61.42% male, at a mean age of 74.52. The diagnostic algorithms used were 52.63% AWGS2, 21.05% EWGSOP2, 10.53% AWGS1 and EWGS1, and 5.26% FNIH. Prevalence ranged from 1.7% to 37.47%, but was higher in males and increased with age. Conclusions: The prevalence of sarcopenia varies depending on the diagnostic algorithm used, but it increases with age and is higher in men. The EWGSOP2 and AWGS2 are the most used diagnostic criteria and measure the same variables but have different cut-off points. Of these two diagnostic algorithms, the one with the highest prevalence of sarcopenia and severe sarcopenia is the AWGS2. These differences may be due to the use of different tools and cut-off points. Therefore, a universal diagnostic criterion should be developed to allow early diagnosis of sarcopenia.

Immunogenetic Aspects of Sarcopenic Obesity

Sarcopenic obesity (SO) is a combination of obesity and sarcopenia, with diagnostic criteria defined as impaired skeletal muscle function and altered body composition (e.g., increased fat mass and reduced muscle mass). The mechanism of SO is not yet perfectly understood; however, the pathogenesis includes aging and its complications, chronic inflammation, insulin resistance (IR), and hormonal changes. Genetic background is apparent in the pathogenesis of isolated obesity, which is most often polygenic and is characterized by the additive effect of various genetic factors. The genetic etiology has not been strictly established in SO. Still, many data confirm the existence of pathogenic gene variants, e.g., Fat Mass and Obesity Associated Gene (FTO), beta-2-adrenergic receptor (ADRB2) gene, melanocortin-4 receptor (MC4R) and others with obesity. The literature on the role of these genes is scarce, and their role has not yet been thoroughly established. On the other hand, the involvement of systemic inflammation due to increased adipose tissue in SO plays a significant role in its pathophysiology through the synthesis of various cytokines such as monocyte chemoattractant protein-1 (MCP-1), IL-1Ra, IL-15, adiponectin or CRP. The lack of anti-inflammatory cytokine (e.g., IL-15) can increase SO risk, but further studies are needed to evaluate the exact mechanisms of implications of various cytokines in SO individuals. This manuscript analyses various immunogenetic and non-genetic factors and summarizes the recent findings on immunogenetics potentially impacting SO development.

Korean Nationwide Exploration of Sarcopenia Prevalence and Risk Factors in Late Middle-Aged Women

This study examined specific clinical risk factors for age-related loss of skeletal muscle mass in late middle-aged women with sarcopenia. This Korean nationwide cross-sectional study analyzed data from 2814 community-dwelling women aged from 50 to 64 years old and screened them for sarcopenia. This study examined various risk factors such as age; height; weight; body mass index; waist circumference; skeletal muscle mass index; systolic and diastolic blood pressure; smoking and drinking habits; fasting glucose levels; triglyceride; and cholesterol levels. Complex sampling analysis was used for the data set. Prevalence of sarcopenia with a weighted prevalence of 13.43% (95% confidence interval: 2.15-15.78). The risk factors for sarcopenia were height, body mass index, waist circumference, skeletal muscle mass index, systolic blood pressure, diastolic blood pressure, triglyceride level, and total cholesterol level (p < 0.05). Weight, fasting glucose level, drinking status, and smoking status were not significant (p > 0.05). These results are expected to contribute to the existing literature on sarcopenia and identify potential risk factors associated with the development of sarcopenia in late middle-aged females. By acknowledging prevalence and recognized risk factors, healthcare professionals may augment their proficiency in recognizing and discerning potential instances of sarcopenia in female patients.

The association between sarcopenia and functional disability in older adults

OBJECTIVES

Sarcopenia is associated with functional disability in older adults. However, no consistent conclusions have been reached considering the differences in the measurement and criteria of sarcopenia. We aimed to examine the association between sarcopenia status and functional disability based on China Health and Retirement Longitudinal Study (CHARLS).

DESIGN

A nationally representative longitudinal study.

SETTING AND PARTICIPANTS

Participants aged at least 60 years old from the CHARLS 2015y were included.

MEASUREMENTS

Sarcopenia was assessed according to the Asian Working Group for Sarcopenia 2019 algorithm. The outcomes of this study were basic activities of daily living (ADLs) and instrumental activities of daily living (IADLs). The logistic regression model was conducted to analyze the cross-sectional and longitudinal associations between sarcopenia status and ADLs and IADLs disability.

RESULTS

In the cross-sectional study, 37.2% of the 6893 participants were defined as having sarcopenia. Any form of sarcopenia was associated with ADLs and IADLs disability. During three years of follow-up, 786 (16.5%) participants developed new-onset ADLs disability, and 980 (22.5%) participants developed new-onset IADLs disability. Compared with the no-sarcopenia, participants with possible sarcopenia (OR: 1.62, 95%CI: 1.34-1.95), sarcopenia (OR: 1.58, 95%CI: 1.18-2.11), or total sarcopenia (OR: 1.58, 95%CI: 1.34-1.88) had a higher risk of ADLs disability. While, the risk of IADLs disability for participants with possible sarcopenia (OR: 1.68, 95%CI: 1.41-2.00), sarcopenia (OR: 1.87, 95%CI: 1.40-2.51), or total sarcopenia (OR: 1.71, 95%CI: 1.45-2.00) was still significantly increased. With statistical interaction between sarcopenia status and residence or sex in ADLs and IADLs disability, older adults in urban, with ORs ranging from 2.14 to 2.44, were at a higher risk of functional disability than those in rural. Possible sarcopenia was associated with a much higher risk of ADLs disability (OR: 1.68, 95%CI: 1.26-2.25) in males and a higher risk of IADLs disability (OR: 1.98, 95%CI: 1.56-2.52) in females.

CONCLUSIONS

Sarcopenia was associated with an increased risk of ADLs and IADLs disability among older Chinese adults. Even possible sarcopenia still significantly impacted ADLs and IADLs disability, and this association varied by sex and residence.

Higher systemic immune-inflammation index is associated with sarcopenia in individuals aged 18-59 years: a population-based study

The association between the systemic immune-inflammation index (SII) and the risk of sarcopenia has not yet been revealed. The purpose of this study was to investigate the relationship between the SII and sarcopenia in individuals aged 18-59 years. All data for this study are from the National Health and Nutrition Examination Survey (NHANES) database, including 7258 participants (age range: 18-59 years). We divided SII values by quartiles (quartiles 1-4: 0.3-3.1, 3.2-4.4, 4.4-6.2, and 6.2-58.5). We constructed a multivariate logistic regression model to assess the association between the SII and the risk of sarcopenia, and an interaction test was run to test the stability of the model and identify high-risk individuals with sarcopenia. Compared to nonsarcopenia participants, sarcopenia patients had a significantly higher SII value (weighted average: 6.65 vs. 5.16) (P = 0.002). Multivariate logistic regression results showed a positive linear relationship between the SII and sarcopenia (OR [odds ratio] = 1.12, 95% CI [confidence interval] 1.03-1.21). Compared to the quartile 1 group, the quartile 4 group was associated with a higher risk of sarcopenia (OR = 3.94, 95% CI 1.42-10.94). Compared with the quartile 1 group, the OR value of the quartile 2 to quartile 4 groups showed an upwards trend (Ptrend < 0.001) as the level of SII increased. Subgroup analysis also indicate that the correlation between higher SII values and the risk of sarcopenia was stable. There was a significant positive linear relationship between SII and sarcopenia, indicating that higher SII values can increase the risk of sarcopenia in individuals aged 18-59 in the United States. The findings of this study will be beneficial in promoting the use of SII alone or in combination with other tools for the risk screening of sarcopenia in communities or large populations.

Sarcopenic Obesity as a Risk Factor for Cardiovascular Disease: An Underrecognized Clinical Entity

Sarcopenic obesity (SO) is a chronic condition and an emerging health challenge, in view of the growing elderly population and the obesity epidemic. Due to a lack of awareness among treating doctors and the non-specific nauture of the associated symptoms, SO remains grossly underdiagnosed. There is no consensus yet on a standard definition or diagnostic criteria for SO, which limits the estimation of the global prevalence of this condition. It has been linked to numerous metabolic derangements, cardiovascular disease (CVD) and mortality. The treatment of SO is multimodal and requires expertise across multiple specialties. While dietary modifications and exercise regimens have shown a potential therapeutic benefit, there is currently no proven pharmacological management for SO. However, numerous drugs and the role of bariatric surgery are still under trial, and have great scope for further research. This article covers the available literature regarding the definition, diagnostic criteria, and prevalence of SO, with available evidence linking it to CVD, metabolic disease and mortality, and an overview of current directives on management.

Predictive Capability of 5 Sarcopenia Diagnostic Criteria for Fall Incidents in Older Japanese Women: The Otassha Study

OBJECTIVES

The association between sarcopenia diagnosis according to various diagnostic criteria and falls is unclear. We examined the association between sarcopenia defined by 5 different international criteria, and fall and injurious fall numbers among older community-dwelling Japanese women.

DESIGN

Prospective observational study.

SETTING AND PARTICIPANTS

Two population-based cohort studies in Itabashi, Japan, were integrated, including 552 community-dwelling Japanese women >75 years of age.

METHODS

Muscle mass, muscle strength, and physical performance were assessed by bioimpedance analysis, handgrip strength, and gait speed, respectively. We recorded the fall and injurious fall numbers for 1 year using a diary. The association between sarcopenia diagnosis defined by the Asian Working Group for Sarcopenia (AWGS) 2019, European Working Group on Sarcopenia in Older People 2, Foundation for the National Institutes of Health (FNIH), International Working Group on Sarcopenia, and Society on Sarcopenia, Cachexia, and Wasting Disorders, and fall numbers was assessed by Poisson regression analysis to estimate the incidence rate ratio (IRR) and 95% CI for the presence or absence of sarcopenia.

RESULTS

Of 470 participants (mean age 77.1 ± 8.1 years), 144 reported a combined 352 falls. Overall, 80 individuals experienced a single fall, 64 experienced multiple falls, and 91 experienced injurious falls. Sarcopenia defined by the AWGS 2019 (IRR 1.39, 95% CI 1.10-1.76) and FNIH (IRR 2.55, 95% CI 1.99-3.26) was significantly associated with the number of falls. In addition, sarcopenia defined by the FNIH (IRR 2.72, 95% CI 1.84-4.03) was significantly associated also with the number of injurious falls. No significant association was observed between sarcopenia diagnosis based on the other definitions and fall outcomes.

CONCLUSIONS AND IMPLICATIONS

The AWGS 2019 and FNIH sarcopenia definitions were associated with the fall and injurious fall numbers in older Japanese women, indicating they can help in predicting falls in this population.

Defining and diagnosing sarcopenia: Is the glass now half full?

Low muscle mass and function exert a substantial negative impact on quality of life, health and ultimately survival, but their definition, identification and combination to define sarcopenia have suffered from lack of universal consensus. Methodological issues have also contributed to incomplete agreement, as different approaches, techniques and potential surrogate measures inevitably lead to partly different conclusions. As a consequence: 1) awareness of sarcopenia and implementation of diagnostic procedures in clinical practice have been limited; 2) patient identification and evaluation of therapeutic strategies is largely incomplete. Significant progress has however recently occurred after major diagnostic algorithms have been developed, with common features and promising perspectives for growing consensus. At the same time, the need for further refinement of the sarcopenia concept has emerged, to address its increasingly recognized clinical heterogeneity. This includes potential differential underlying mechanisms and clinical features for age- and disease-driven sarcopenia, and the emerging challenge of sarcopenia in persons with obesity. Here, we will review existing algorithms to diagnose sarcopenia, and major open methodological issues to assess skeletal muscle mass and function under different clinical conditions, in order to highlight similarities and differences. Potential for consensus on sarcopenia diagnosis as well as emerging new challenges will be discussed.

Sarcopenia and cardiovascular diseases: A systematic review and meta-analysis

Sarcopenia is an age-related disease and is often accompanied by other diseases. Now, many studies have shown that cardiovascular diseases (CVDs) may raise the incidence rate of sarcopenia. Therefore, the purpose of this study was to conduct a systematic review and meta-analysis to investigate the prevalence of sarcopenia in patients with CVDs compared with the general population, defined as relatively healthy non-hospitalized subjects. The databases of PubMed, Embase, Medline and Web of Science were searched for eligible studies published up to 12 November 2022. Two assessment tools were used to evaluate study quality and the risk of bias. Statistical analysis was conducted using STATA 14.0 and R Version 4.1.2. Thirty-eight out of the 89 629 articles retrieved were included in our review. The prevalence of sarcopenia ranged from 10.1% to 68.9% in patients with CVDs, and the pooled prevalence was 35% (95% confidence interval [95% CI]: 28-42%). The pooled prevalence of sarcopenia was 32% (95% CI: 23-41%) in patients with chronic heart failure (CHF), 61% (95% CI: 49-72%) in patients with acute decompensated heart failure (ADHF), 43% (95% CI: 2-85%) in patients with coronary artery disease, 30% (95% CI: 25-35%) in patients with cardiac arrhythmia (CA), 35% (95% CI: 10-59%) in patients with congenital heart disease and 12% (95% CI: 7-17%) in patients with unclassed CVDs. However, in the general population, the prevalence of sarcopenia varied from 2.9% to 28.6% and the pooled prevalence was 13% (95% CI: 9-17%), suggesting that the prevalence of sarcopenia in patients with CVDs was about twice compared with the general population. The prevalence of sarcopenia was significantly higher only in patients with ADHF, CHF and CA compared with the general population. There is a positive correlation between CVDs and sarcopenia. The prevalence of sarcopenia is higher in patients with CVDs than that in the general population. With global aging, sarcopenia has brought a heavy burden to individuals and society. Therefore, it is important to identify the populations with high-risk or probable sarcopenia in order to do an early intervention, such as exercise, to counteract or slow down the progress of sarcopenia.

Sarcopenia parameters in active older adults - an eight-year longitudinal study

BACKGROUD

Sarcopenia is a common skeletal muscle syndrome that is common in older adults but can be mitigated by adequate and regular physical activity. The development and severity of sarcopenia is favored by several factors, the most influential of which are a sedentary lifestyle and physical inactivity. The aim of this observational longitudinal cohort study was to evaluate changes in sarcopenia parameters, based on the EWGSOP2 definition in a population of active older adults after eight years. It was hypothesized that selected active older adults would perform better on sarcopenia tests than the average population.

METHODS

The 52 active older adults (22 men and 30 women, mean age: 68.4 ± 5.6 years at the time of their first evaluation) participated in the study at two time points eight-years apart. Three sarcopenia parameters were assessed at both time points: Muscle strength (handgrip test), skeletal muscle mass index, and physical performance (gait speed), these parameters were used to diagnose sarcop0enia according to the EWGSOP2 definition. Additional motor tests were also performed at follow-up measurements to assess participants' overall fitness. Participants self-reported physical activity and sedentary behavior using General Physical Activity Questionnaire at baseline and at follow-up measurements.

RESULTS

In the first measurements we did not detect signs of sarcopenia in any individual, but after 8 years, we detected signs of sarcopenia in 7 participants. After eight years, we detected decline in ; muscle strength (-10.2%; p < .001), muscle mass index (-5.4%; p < .001), and physical performance measured with gait speed (-28.6%; p < .001). Similarly, self-reported physical activity and sedentary behavior declined, too (-25.0%; p = .030 and - 48.5%; p < .001, respectively).

CONCLUSIONS

Despite expected lower scores on tests of sarcopenia parameters due to age-related decline, participants performed better on motor tests than reported in similar studies. Nevertheless, the prevalence of sarcopenia was consistent with most of the published literature.

TRIAL REGISTRATION

The clinical trial protocol was registered on ClinicalTrials.gov, identifier: NCT04899531.

Design and rationale of re-energize fontan: Randomized exercise intervention designed to maximize fitness in fontan patients

In this manuscript, we describe the design and rationale of a randomized controlled trial in pediatric Fontan patients to test the hypothesis that a live-video-supervised exercise (aerobic+resistance) intervention will improve cardiac and physical capacity; muscle mass, strength, and function; and endothelial function. Survival of children with single ventricles beyond the neonatal period has increased dramatically with the staged Fontan palliation. Yet, long-term morbidity remains high. By age 40, 50% of Fontan patients will have died or undergone heart transplantation. Factors that contribute to onset and progression of heart failure in Fontan patients remain incompletely understood. However, it is established that Fontan patients have poor exercise capacity which is associated with a greater risk of morbidity and mortality. Furthermore, decreased muscle mass, abnormal muscle function, and endothelial dysfunction in this patient population is known to contribute to disease progression. In adult patients with 2 ventricles and heart failure, reduced exercise capacity, muscle mass, and muscle strength are powerful predictors of poor outcomes, and exercise interventions can not only improve exercise capacity and muscle mass, but also reverse endothelial dysfunction. Despite these known benefits of exercise, pediatric Fontan patients do not exercise routinely due to their chronic condition, perceived restrictions to exercise, and parental overprotection. Limited exercise interventions in children with congenital heart disease have demonstrated that exercise is safe and effective; however, these studies have been conducted in small, heterogeneous groups, and most had few Fontan patients. Critically, adherence is a major limitation in pediatric exercise interventions delivered on-site, with adherence rates as low as 10%, due to distance from site, transportation difficulties, and missed school or workdays. To overcome these challenges, we utilize live-video conferencing to deliver the supervised exercise sessions. Our multidisciplinary team of experts will assess the effectiveness of a live-video-supervised exercise intervention, rigorously designed to maximize adherence, and improve key and novel measures of health in pediatric Fontan patients associated with poor long-term outcomes. Our ultimate goal is the translation of this model to clinical application as an "exercise prescription" to intervene early in pediatric Fontan patients and decrease long-term morbidity and mortality.

Handgrip strength conditional tolerance regions suggest the need for personalized sarcopenia definition: an analysis of the American NHANES database

BACKGROUND

Handgrip strength (HGS) is a well-established clinical biomarker that assesses functional capacity in older populations. In addition, HGS is a diagnostic tool that forecasts aging health conditions, such as sarcopenia.

AIMS

This paper provides HGS statistical tolerance regions and presents the need to establish HGS reference values according to patients' characteristics.

METHODS

For this purpose, we used a conditional tolerance algorithm for HGS, and we observed the tolerances regions in different age strata and sex of non-sarcopenic individuals from the National Health and Nutrition Examination Survey (NHANES, wave 2011-2012).

RESULTS AND DISCUSSION

Our results have critical implications for sarcopenia, since conventional and available HGS cut-offs do not consider age range.

CONCLUSIONS

This paper offers new perspectives on the evolution of traditional definitions of sarcopenia according to the principles of precision medicine.

Serum 25 hydroxyvitamin D concentrations in individuals over 80 years old and their correlations with musculoskeletal and health parameters

PURPOSE

The present study aims to evaluate the serum concentrations of 25 hydroxyvitamin D[25(OH)D] in individuals aged ≥80 years, independent, free-living in Sao Paulo, Brazil (Lat 23.5 ^oS), and to investigate their associations with musculoskeletal system, physical performance and health markers.

METHOD

This cross-sectional study included 212 community dwellers aged ≥80 years and evaluated serum 25(OH)D, PTH, calcium, albumin, phosphorus, creatinine, bone markers, and bone mineral density. Physical performance was evaluated with stationary march, Flamingo, and functional reach tests, questionnaires to assess falls and fractures in the previous year, energy expenditure (MET), and Charlson index. Physical activity was evaluated with the International Physical Activity Questionnaire.

RESULTS

Vitamin D deficiency (<20 ng/mL) was observed in 56% and severe vitamin D deficiency (<10 ng/mL) in 13% of those individuals. Serum concentrations of 25(OH)D were significantly and positively associated with BMD total hip (p = 0.001), femoral neck (p = 0.011) and 33% radius (p = 0.046) BMDs, MET (p = 0.03) and functional reach test (p = 0.037) and negatively with age (p = 0.021), PTH (p = 0.004) and osteoporosis diagnosis (p = 0.012). Long-lived individuals with 25(OH)D ≥ 20 ng/mL had higher total hip and femoral neck BMDs (p = 0.012 and p = 0.014, respectively) and lower PTH (p = 0.030). In multiple linear regression analysis, age and osteoporosis diagnosis remained negatively associated with 25(OH)D levels (p = 0.021 and p = 0.001, respectively), while corrected calcium and cholecalciferol use remained positively associated (p = 0.001 and p = 0.024, respectively).

CONCLUSION

We observed high vitamin D inadequacy prevalence in those Brazilian community dwellers' oldest old. Serum concentrations of 25(OH)D were positively associated with bone mass and dynamic balance, and negatively with PTH and osteoporosis diagnosis. Additionally, 25(OH)D ≥ 20 ng/mL was associated with better bone mass and lower PTH levels.

Anthropometric equations to estimate appendicular muscle mass from dual-energy X-ray absorptiometry (DXA): A scoping review

BACKGROUND

Appendicular skeletal muscle mass (ASM) obtained from dual-energy x-ray absorptiometry (DXA) is recommended to quantify sarcopenia, but has limited availability in disadvantaged-income countries, moreover in an epidemiological context. Predictive equations are easier and less costly to apply, but a review of all available models is still lacking in the scientific literature. The objective of this work is to map, with a scoping review, the different proposed anthropometric equations to predict ASM measured by DXA.

METHODS

Six databases were searched without restriction on publication date, idiom, and study type. A total of 2,958 studies were found, of which 39 were included. Eligibility criteria involved ASM measured by DXA, and equations proposed to predict ASM.

RESULTS

predictive equations (n = 122) were gathered for 18 countries. The development phase involves sample size, coefficient of determination (r²), and a standard error of estimative (SEE) varying between 15 and 15,239 persons, 0.39 and 0.98, 0.07 and 3.38 kg, respectively. The validation phase involves a sample size, accuracy, and a SEE between 15 and 3,003 persons, 0.61 and 0.98, 0.09 and 3.65 kg, respectively.

CONCLUSIONS

The different proposed predictive anthropometric equations of ASM DXA were mapped, including validated pre-existing equations, offering an easy-to-use referential article for clinical and research applications. It is necessary to propose more equations for other continents (Africa and Antarctica) and specific health-related conditions (e.g., diseases), once the equations can only have sufficient validity and accuracy to predict ASM generally when applied to the same population.

Crucial Regulatory Role of Organokines in Relation to Metabolic Changes in Non-Diabetic Obesity

Obesity is characterized by an excessive accumulation of fat leading to a plethora of medical complications, including coronary artery disease, hypertension, type 2 diabetes mellitus or impaired glucose tolerance and dyslipidemia. Formerly, several physiological roles of organokines, including adipokines, hepatokines, myokines and gut hormones have been described in obesity, especially in the regulation of glucose and lipid metabolism, insulin sensitivity, oxidative stress, and low-grade inflammation. The canonical effect of these biologically active peptides and proteins may serve as an intermediate regulatory level that connects the central nervous system and the endocrine, autocrine, and paracrine actions of organs responsible for metabolic and inflammatory processes. Better understanding of the function of this delicately tuned network may provide an explanation for the wide range of obesity phenotypes with remarkable inter-individual differences regarding comorbidities and therapeutic responses. The aim of this review is to demonstrate the role of organokines in the lipid and glucose metabolism focusing on the obese non-diabetic subgroup. We also discuss the latest findings about sarcopenic obesity, which has recently become one of the most relevant metabolic disturbances in the aging population.

Cross-cultural adaptation and validation of Sarcopenia and Quality of Life (SarQoL) in Brazil

BACKGROUND

Sarcopenia is defined as a slow, progressive, and apparently inevitable process of involuntary loss of muscle mass, strength, and quality, which occurs with advancing age. It is widely accepted that sarcopenia can directly affect quality of life.

OBJECTIVE

Translate, adapt and validate the "Sarcopenia and Quality of Life" instrument (SarQoL) to the Brazilian context.

DESIGN AND SETTINGS

Translation, cross-cultural adaptation, and validation study carried out at the Federal University of São Carlos, São Carlos, São Paulo, Brazil.

METHODS

The population consisted of 221 older adult participants. The steps recommended by the guidelines from the authors of the original instrument were followed sequentially: initial translation, synthesis of translations, backward translation, evaluation by a panel of judges, pre-test, and analysis of psychometric properties. The translation and adaptation process was conducted as recommended.

RESULTS

Two hundred and twenty-one participants took part in the step analysis of the psychometric properties of SarQoL, in which 55 presented sarcopenia. Cronbach's alpha coefficient of the total SarQoL questionnaire was 0.976, indicating excellent internal consistency. Excellent agreements between the test and retest with an Interclass Correlation Coefficient (ICC) of 0.983 (95% confidence interval: 0.901-0.996) were observed in the SarQoL domains. The domains of Short-Form 36 and EuroQoL 5-dimension showed significant correlation, from moderate to strong magnitude, with SarQoL total score, indicating convergent validity.

CONCLUSION

The Brazilian version of SarQoL presented evidence of reliability and validity.

Association of sarcopenia with important health conditions among community-dwelling Asian women

This study aimed to examine sarcopenia prevalence using the Asian Working Group for Sarcopenia 2019 (AWGS) and the Foundation for the National Institutes of Health (FNIH) definitions, and their associations with important health conditions affecting midlife Singaporean women. Muscle mass and function were objectively assessed in 1201 healthy community-dwelling subjects aged 45-69 years under the Integrated Women's Health Program (IWHP). Dual-energy X-ray absorptiometry (DXA), handgrip strength and the Short Physical Performance Battery (SPPB) were measured, and the relationship between sarcopenia with hypertension, type 2 diabetes (T2DM), osteoporosis, depression/anxiety, and urinary incontinence were examined using binary logistic regression models. Sarcopenia prevalence was 18.0% and 7.7% by the AWGS and FNIH criteria respectively. Osteoporosis (aOR: 1.74, 95% CI: 1.02, 2.94) and T2DM (aOR: 1.98, 95% CI: 1.14, 3.42) was positively associated with AWGS- and FNIH-defined sarcopenia respectively, while hypertension was not, after adjustment for age, ethnicity, education levels and menopausal status. A negative percent agreement of 95.6% suggests good agreement between the criteria in the absence of sarcopenia. Even though they represent a single concept, sarcopenia by either criterion differed in their relationships with diabetes and osteoporosis, suggesting the need for further rationalization of diagnostic criteria.

Impact of Change in Body Composition during Follow-Up on the Survival of GEP-NET

Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are heterogeneous rare diseases causing malnutrition and cachexia in which the study of body composition may have an impact in prognosis. Aim: Evaluation of muscle and fat tissues by computed tomography (CT) at the level of the third lumbar (L3 level) at diagnosis and at the end of follow-up in GET-NET patients and their relationships with clinical and biochemical variables as predictors of survival. Methodology: Ninety-eight GEP-NET patients were included. Clinical and biochemical parameters were evaluated. Total body, subcutaneous, visceral and total fat areas and very low-density, low-density, normal density, high-density, very high-density and total muscle areas were obtained from CT images. Results: Body composition measures and overall mortality correlated with age, ECOG (Eastern Cooperative Oncology Group performance status) metastases, lactate dehydrogenase (LDH), albumin and urea levels. Although there was no relationship between body composition variables at diagnosis and overall and specific mortality, an increase in low-density muscle and a decrease in normal-density muscle during follow-up were independently correlated to overall (p <0.05) and tumor-cause mortality (p < 0.05). Conclusion: Although body composition measures obtained by CT at diagnosis did not impact survival of GEP-NET patients, a loss of good quality muscle during follow-up was associated with an increased overall and tumor-related mortality. Nutritional status should therefore be supervised by nutrition specialists and an increase in good quality muscle could improve prognosis.

Sex Differences of Sarcopenia in an Elderly Asian Population: The Prevalence and Risk Factors

The loss of muscle mass is widespread in age-related health phenomena in the elderly population. This study examined the prevalence of sarcopenia in a community-dwelling elderly population according to gender. The study also identified gender-specific risk factors in older people aged 75-84 years old. One thousand two hundred and ninety-three participants aged between 75 and 84 years from the National Health and Nutrition Examination Surveys in Korea were investigated. The prevalence of sarcopenia in males and females in the weighted-value sample was 41.2% (95%CI: 35.8-46.8) and 37.2% (32.7-41.9), respectively. Gender-specific clinical risk factors in males were height, weight, body mass index, waist circumference, skeletal muscle mass index, fasting glucose, and triglyceride levels. Height, weight, body mass index, waist circumference, skeletal muscle mass index, and total cholesterols were clinical risk factors for females. These outcomes would be crucial to primary care clinicians and health care professionals when patients require a referral for early detection and treatment. Health care professionals and clinicians can quickly identify potential sarcopenic patients by acknowledging the gender-specific prevalence and risk factors.

Is handgrip strength a marker of muscle and physical function of the lower limbs? Sex differences in older adults with obesity

BACKGROUND AND AIMS

In this cross-sectional study we investigate the association between handgrip strength (HGS) and muscle function of the lower limbs and the predictors of the appendicular lean mass index (ALMI) in older adults with obesity of both sexes.

METHODS AND RESULTS

Eighty-four older (67 ± 5 years) men (N = 44) and women (N = 40) with obesity (body mass index (BMI) 33 ± 4 kg/m²) performed: the HGS, isokinetic knee extensors (KE) and flexors (KF) muscle strength and power and Short Physical Performance Battery (SPPB). The correlation between HGS and lower limbs muscle function was evaluated, and four multiple hierarchical linear models were built to assess the contribution of each ALMI predictor (i.e., HGS, BMI, SPPB, muscle strength and power). In men, HGS was weakly-to-moderately associated (p < 0.05) with KE, KF muscle function and physical performance. In women, HGS showed a weak association (p < 0.05) with KE muscle function. The significant predictors of ALMI were only the BMI in women, whereas in the group of men BMI, KE maximal strength and power better explain the variance in ALMI than HGS alone.

CONCLUSION

Our results suggest that HGS should not be used alone as a marker of lower muscle nor physical function. Sex differences exist with the BMI that is a contributor of ALMI both in men and women. However, at least in the group of men, markers related to strength and power of the lower limbs can better describe variations in ALMI compared to HGS in this kind of population.

CLINICAL TRIAL REGISTRATION

NA.

Diagnostic and prognostic value of the Creatinine/Cystatin C ratio for low muscle mass evaluation among US adults

Background

Identifying patients with low muscle mass is crucial for the diagnosis of sarcopenia. Although the Creatinine/Cystatin C (Cr/CysC) is recommended as a simplified indicator to identify patients with low muscle mass, its ability to assess muscle mass and predict a poor prognosis has not been validated. We aimed to determine the diagnosis value of Cr/CysC for low muscle mass and examine the association of Cr/CysC with mortality.

Methods

In this cohort study we analyzed data from the National Health and Nutrition Examination Survey from 1999 to 2002. Follow-up was conducted up to December, 2015. Appendicular skeletal mass was calculated based on dual-energy X-ray absorptiometry (DXA) scans. Low muscle mass was defined referring to five international diagnostic criteria. The diagnostic value of Cr/CysC as a replacement indicator of muscle mass was measured using area under the curve, positive percent agreement, negative percent agreement and kappa. Cox proportional hazards regression models were developed to examine the association between Cr/CysC and risk of mortality.

Results

This cohort study of 3,741 adults comprised 1,823 females (48.73%), with a weighted mean (SE) age of 44.46 (0.43) years. The positive percent agreement of Cr/CysC for the diagnosis of low muscle mass was poor (40.23–58.74%), except for Foundation of the National Institute of Health (FNIH) criteria (80.90–58.97%). But the negative percent agreement of Cr/CysC for the diagnosis of low muscle mass was high (males: 62.15–88.17%; females: 55.26–82.30%). Moreover, the risk of death was reduced by 2% per 0.01 unit increase in Cr/CysC (aHR, 0.98; 95% CI, 0.98–0.99, P < 0.001).

Conclusions

Cr/CysC performed well not only in identifying non-sarcopenia cases, especially when based on FNIH diagnostic criteria, but also in revealing a positive association with higher risk of mortality. The optimal cut-off values for Cr/CysC were <1.0 in males and <0.8 in females. Expanding the use of Cr/CysC would allow for early and targeted treatment of sarcopenia.

Bibliometric Analysis of the Knowledge Base and Future Trends on Sarcopenia from 1999–2021

Sarcopenia is characterized by progressive loss of muscle mass and function, and it is becoming a serious public health problem with the aging population. However, a comprehensive overview of the knowledge base and future trends is still lacking. The articles and reviews with “sarcopenia” in their title published from 1999 to 2021 in the SCIE database were retrieved. We used Microsoft Excel, VOSviewer, and CiteSpace to conduct a descriptive and bibliometric analysis. A total of 3582 publications were collected, from 4 published in 2000 increasing dramatically to 850 documents in 2021. The USA was the most productive country, with the most citations. The Catholic University of the Sacred Heart and Landi F were the most influential organization and author in this field, respectively. The core journal in this field was the Journal of Cachexia Sarcopenia and Muscle. According to the analysis of keywords and references, we roughly categorized the main research areas into four domains as follows: 1. Definition and diagnosis; 2. Epidemiology; 3. Etiology and pathogenesis; 4. Treatments. Comparing different diagnostic tools and the epidemiology of sarcopenia in different populations are recent hotspots, while more efforts are needed in the underlying mechanism and developing safe and effective treatments. In conclusion, this study provides comprehensive insights into developments and trends in sarcopenia research that can help researchers and clinicians better manage and implement their work.

Protein Intake and Sarcopenia in Older Adults: A Systematic Review and Meta-Analysis

Background: The present systematic review and meta-analysis investigated the cross-sectional and longitudinal associations between protein intake and sarcopenia in older adults. Methods: Observational studies that investigated the association between protein intake and sarcopenia as the primary or secondary outcome in people aged 60 years and older were included. Studies published in languages other than English, Italian, Portuguese, and Spanish were excluded. Studies were retrieved from MEDLINE, SCOPUS, EMBASE, CINAHL, AgeLine, and Food Science Source databases through January 31, 2022. A pooled effect size was calculated based on standard mean differences. Results: Five cross-sectional studies, one longitudinal study, and one case-control study that investigated 3353 community-dwelling older adults with a mean age of approximately 73 years were included. The meta-analysis of four studies indicated that older adults with sarcopenia consumed significantly less protein than their peers with no sarcopenia. Conclusions: Results of the present study suggest that an inadequate protein intake might be associated with sarcopenia in older adults.

Sarcopenia: an unsolved problem after hip fracture

INTRODUCTION

Sarcopenia, loss of muscle mass and strength, leads to functional dependence and disability. To date, no study reported the postoperative change of sarcopenia prevalence after hip fractures. Thus, we assessed postoperative changes in the prevalence of osteoporosis and sarcopenia in hip fracture patients.

MATERIALS AND METHODS

Among 1159 patients, who underwent surgery for low-energy hip fractures between May 2012 and December 2019, 224 patients (38 men and 186 women with a mean age of 76.8 ± 8.7 years) were studied with preoperative and follow-up dual-energy X-ray absorptiometry (DXA). Bone mineral density (BMD) and skeletal muscle mass were measured on DXA scans. The postoperative changes in the prevalence of osteoporosis and that of the sarcopenia were evaluated as well as Koval grade of the hip fracture patients.

RESULTS

While there was no significant change in BMD, SMI significantly decreased postoperatively. Mean decrease of the SMI was 0.53 kg/m2 in men and 0.38 kg/m2 in women. Prevalence of sarcopenia increased from 63 to 89% (p = 0.014) in men and from 45 to 57% (p = 0.006) in women. Lower BMI (Odds ratio (OR) 0.85 (95% confidence interval (CI) 0.76-0.96), p = 0.008) and prior sarcopenia (OR 14.47 (95% CI 5.29-35.39), p < 0.001) were the risk factors for the decrease of SMI after hip fracture.

CONCLUSIONS

After hip fracture, osteoporosis seemed to be well managed and the prevalence of osteoporosis did not increase. However, SMI decreased and the prevalence of sarcopenia increased. More active measures are warranted to prevent sarcopenia in elderly hip fracture patients.

Gender-Specific Risk Factors and Prevalence for Sarcopenia among Community-Dwelling Young-Old Adults

Sarcopenia in the elderly is a serious global public health problem. Numerous sarcopenia studies classified their subjects into a single group, but health conditions and body composition vary according to age. This study examined the prevalence of sarcopenia according to gender and assessed the gender-specific risk factors in young-old adults. In this study, 2697 participants in Korea aged from 65 to 74 years were analyzed from Korea National Health and Nutrition Examination Surveys. The prevalence of sarcopenia in males and females was 19.2% (CI 95%: 16.4–22.3) and 26.4% (23.7–29.4), respectively. The risk factors in men were age, body mass index (BMI), waist circumference (WC), skeletal muscle index (SMI), fasting glucose (FG), triglyceride, and systolic blood pressure (SBP). Their odd ratios were 1.447, 0.102, 1.494, 0.211, 0.877, 1.012, and 1.347. The risk factors in women were age, height, weight, BMI, WC, SMI, and fasting glucose with values of 1.489, 0.096, 0.079, 0.158, 0.042, and 1.071, respectively. The prevalence of sarcopenia was higher in females than in males. Overall, the clinical risk factors in males were age, height, BMI, WC, SMI, FG, triglyceride, and SBP. Age, height, weight, BMI, WC, SMI, and FG were the risk factors for women.

FGF23 levels as a marker of physical performance and falls in community-dwelling very old individuals

Objective

The fibroblast growth factor 23 (FGF23) has been related to biological aging, but data in elderly individuals are scant. We determined the profile of serum FGF23 levels in a population of very-old individuals and studied their correlations with parameters of bone metabolism and health markers, as functional performance.

Methods

This cross-sectional study was performed on 182 community dwellers aged ≥ 80 years. Serum levels of FGF23, PTH, calcium, albumin, phosphorus, creatinine, bone markers, and bone mineral density data were analyzed. Physical performance was evaluated with the stationary march (Step), Flamingo, and functional reach tests, along with questionnaires to assess falls and fractures in the previous year, energy expenditure (MET), and the Charlson index (CI). Physical activity was evaluated with the International Physical Activity Questionnaire (IPAQ).

Results

Most participants (75%) had FGF23 levels between 30-120 RU/mL (range: 6.0-3,170.0 RU/mL). FGF23 levels correlated with estimated glomerular filtration rate (eGFR; r = -0.335; p = 0.001) and PTH (r = 0.318; p < 0.0001). Individuals with FGF23 in the highest tertile had more falls in the previous year (p = 0.032), worse performance in the Flamingo (p = 0.009) and Step (p < 0.001) tests, worse CI (p = 0.009) and a trend toward sedentary lifestyle (p = 0.056). On multiple regression, FGF23 tertiles remained significant, independently of eGFR, for falls in the previous year, performance in the Flamingo and stationary march tests, lean mass index, and IPAQ classification.

Conclusion

In a population of very elderly individuals, FGF23 levels were inversely associated with neuromuscular and functional performances. Higher concentrations were related to more falls, lower muscle strength and aerobic capacity, and poorer balance, regardless of renal function, suggesting a potentially deleterious role of high FGF23 concentrations in musculoskeletal health.

High Intensity Interval Training: A Potential Method for Treating Sarcopenia

Sarcopenia, an age-related disease characterized by loss of muscle strength and muscle mass, has attracted the attention of medical experts due to its severe morbidity, low living quality, high expenditure of health care, and mortality. Traditionally, persistent aerobic exercise (PAE) is considered as a valid way to attenuate muscular atrophy. However, nowadays, high intensity interval training (HIIT) has emerged as a more effective and time-efficient method to replace traditional exercise modes. HIIT displays comprehensive effects on exercise capacity and skeletal muscle metabolism, and it provides a time-out for the recovery of cardiopulmonary and muscular functions without causing severe adverse effects. Studies demonstrated that compared with PAE, HIIT showed similar or even higher effects in improving muscle strength, enhancing physical performances and increasing muscle mass of elder people. Therefore, HIIT might become a promising way to cope with the age-related loss of muscle mass and muscle function. However, it is worth mentioning that no study of HIIT was conducted directly on sarcopenia patients, which is attributed to the suspicious of safety and validity. In this review, we will assess the effects of different training parameters on muscle and sarcopenia, summarize previous papers which compared the effects of HIIT and PAE in improving muscle quality and function, and evaluate the potential of HIIT to replace the status of PAE in treating old people with muscle atrophy and low modality; and point out drawbacks of temporary experiments. Our aim is to discuss the feasibility of HIIT to treat sarcopenia and provide a reference for clinical scientists who want to utilize HIIT as a new way to cope with sarcopenia.

Official Position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry-part II (clinical aspects): interpretation, reporting, and special situations

OBJECTIVE

To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice.

MATERIALS AND METHODS

This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals.

CONCLUSION

This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.

Relationships Between Depressive Symptoms, Dietary Inflammatory Potential, and Sarcopenia: Mediation Analyses

Background

Sarcopenia is a major public health problem. Depressive symptoms and dietary inflammatory potential play important roles in the development of sarcopenia. We aimed to disentangle the relationships between depressive symptoms, dietary inflammatory potential, and sarcopenia.

Methods

A total of 6,082 participants from the National Health and Nutrition Examination Survey (NHANES) were included in the analyses. Sarcopenia was defined according to the Foundation for the National Institutes for Health (FNIH) criteria. The Depressive symptoms were assessed using the nine-item Patient Health Questionnaire (PHQ-9). Dietary Inflammatory Index (DII) was calculated based on 24-h dietary recall interview. Two sets of mediation models were constructed separately.

Results

Depressive symptoms and DII were associated with sarcopenia, with odds ratios [ORs] (95% CIs) 2.54 (1.27, 5.13) and 1.17 (1.00, 1.37), respectively. DII score mediated the association of depressive symptoms with low muscle mass, explaining a total of 10.53% of the association (indirect effect = 0.004). Depressive symptoms had a significant mediating effects on the association between DII with low muscle mass, explaining a total of 12.50% of the association (indirect effect = 0.001).

Conclusions

Our findings suggested that both depressive symptoms and dietary inflammatory potential had direct effects, and indirect effects on low muscle mass, handgrip strength, muscle mass, through each other. It provides important insights into integrated nutritional and psychological intervention strategies in preventing sarcopenia.

Sarcopenia in Chronic Kidney Disease: A Scoping Review of Prevalence, Risk Factors, Association with Outcomes, and Treatment

Sarcopenia, a condition characterized by loss of skeletal muscle mass and function, has important clinical ramifications. We aimed to map the existing literature about prevalence, risk factors, associated adverse outcomes, and treatment of sarcopenia in individuals with chronic kidney disease (CKD). A scoping review of the literature was conducted to identify relevant articles published from databases' inception to September 2019. Individuals with CKD, regardless of their disease stage and their comorbidities, were included. Only studies with sarcopenia diagnosed using both muscle mass and function, based on published consensus definitions, were included. For studies on treatment, only randomized controlled trials with at least one sarcopenia parameter as an outcome were included. Our search yielded 1318 articles, of which 60 from were eligible for this review. The prevalence of sarcopenia ranged from 4 to 42% according to the definition used, population studied, and the disease stage. Several risk factors for sarcopenia were identified including age, male gender, low BMI, malnutrition, and high inflammatory status. Sarcopenia was found to be associated with several adverse outcomes, including disabilities, hospitalizations, and mortality. In CKD subjects, several therapeutic interventions have been assessed in randomized controlled trial with a muscle mass, strength, or function endpoint, however, studies focusing on sarcopenic CKD individuals are lacking. The key interventions in the prevention and treatment of sarcopenia in CKD seem to be aerobic and resistance exercises along with nutritional interventions. Whether these interventions are effective to treat sarcopenia and prevent clinical consequences in this population remains to be fully determined.

A Multifactorial Approach for Sarcopenia Assessment: A Literature Review

Simple Summary

Sarcopenia is characterized by an accelerated decline in skeletal muscle mass and strength, which results in poor quality of life, disability, and death. In the literature, sarcopenia is defined as the progressive breakdown of muscle tissue. The prevalence ranges from 5% to 13% in people 60–70 years old and from 11% to 50% in people older than 80 years. The comparison of risk factors associated with sarcopenia based on the European Working Group on Sarcopenia (1 and 2) in Older People, the Asian Working Group for Sarcopenia (1 and 2), the International Working Group on Sarcopenia, and the Foundation for the National Institutes of Health revealed no consistent patterns. Accordingly, the identification of a single risk factor for sarcopenia is unpredictable. Due to its “multifactorial” pathogenesis related to the involvement of a multitude of factors. In this review, we summarize 13 relevant risk factors associated with this disease that are important to consider prior to embarking on any related sarcopenia research. We suggest that researchers should concentrate on the biology of sarcopenia to develop a uniform consensus for screening this condition. In this review, we identify 50 biochemical markers across six pathways that have previously been investigated in subjects with sarcopenia. We suggest that these summarized biomarkers can be considered in future diagnosis to determine the biology of this disorder, thereby contributing to further research findings. As a result, a uniform consensus may also need to be established for screening and defining the disease. Sarcopenia is associated with a number of adverse economic and social outcomes, including disability, hospitalization, and death. In relation to this, we propose that we need to develop strategies including exercise interventions in the COVID-19 era to delay the onset and effects of sarcopenia. This suggestion should impact on sarcopenia’s primary and secondary outcomes, including physical, medical, social, and financial interactions.

Abstract

Sarcopenia refers to a progressive and generalized weakness of skeletal muscle as individuals age. Sarcopenia usually occurs after the age of 60 years and is associated with a persistent decline in muscle strength, function, and quality. A comparison of the risk factors associated with sarcopenia based on the European Working Group on Sarcopenia (1 and 2) in Older People, the Asian Working Group for Sarcopenia (1 and 2), the International Working Group on Sarcopenia, and the Foundation for the National Institutes of Health revealed no consistent patterns. Accordingly, the identification of a single risk factor for sarcopenia is unpredictable due to its “multifactorial” pathogenesis, with the involvement of a multitude of factors. Therefore, the first aim of this review was to outline and propose that the multiple factors associated with sarcopenia need to be considered in combination in the design of new experimentation in this area. A secondary aim was to highlight the biochemical risk factors that are already identified in subjects with sarcopenia to assist scientists in understanding the biology of the pathophysiological mechanisms affecting the old people with sarcopenia. We also briefly discuss primary outcomes (physical) and secondary outcomes (social and financial) of sarcopenia. For future investigative purposes, this comprehensive review may be useful in considering important risk factors in the utilization of a panel of biomarkers emanating from all pathways involved in the pathogenesis of this disease. This may help to establish a uniform consensus for screening and defining this disease. Considering the COVID-19 pandemic, its impact may be exacerbated in older populations, which requires immediate attention. Here, we briefly suggest strategies for advancing the development of smart technologies to deliver exercise in the COVID-19 era in an attempt regress the onset of sarcopenia. These strategies may also have an impact on sarcopenia’s primary and secondary outcomes.

The impact of variation in the device used to measure grip strength on the identification of low muscle strength: Findings from a randomised cross-over study

Grip strength is commonly used to identify people with low muscle strength. It is unclear what impact the type of dynamometer used to measure grip strength has on the identification of low muscle strength so we aimed to assess this. Study participants were 118 men and women aged 45-74y from a randomised, repeated measurements cross-over study. Maximum grip strength was assessed using four hand-held dynamometers (Jamar Hydraulic; Jamar Plus+ Digital; Nottingham Electronic; Smedley) in a randomly allocated order. EWGSOP2 cut-points were applied to estimate prevalence of low muscle strength for each device. Agreement between devices was compared. Prevalence of low muscle strength varied by dynamometer ranging between 3% and 22% for men and, 3% and 15% for women. Of the 13 men identified as having low muscle strength by at least one of the four dynamometers, only 8% were identified by all four and 54% by just one. Of the 15 women classified as having low muscle strength by at least one of the four dynamometers, only 7% were identified by all four and 67% by only one. Variation in the measures of grip strength acquired by different hand-held dynamometers has potentially important implications when identifying low muscle strength.

U-TEST, a simple decision support tool for the diagnosis of sarcopenia in orthopaedic patients: the Screening for People Suffering Sarcopenia in Orthopedic cohort of Kobe study (SPSS-OK)

We aimed to develop and validate a new simple decision support tool (U-TEST) for diagnosis of sarcopenia in orthopaedic patients. We created seventeen candidate original questions to detect sarcopenia in orthopaedic patients with sarcopenia through expert opinions and a semi-structured interview. To derive a decision support tool, a logistic regression model with backward elimination was applied to select variables from the seventeen questions, age and underweight (BMI < 18·5 kg/m2). Sarcopenia was defined by Asian Working Group for Sarcopenia 2019 criteria. After assigning a score to each selected variable, the sum of scores was calculated. We evaluated the diagnostic performance of the new tool using a logistic regression model. A bootstrap technique was used for internal validation. Among a total of 1334 orthopaedic patients, sixty-five (4·9 %) patients were diagnosed with sarcopenia. We succeeded in developing a 'U-TEST' with scores ranging from 0 to 11 consisting of values for BMI (Underweight), age (Elderly) and two original questions ('I can't stand up from a chair without supporting myself with my arms' (Strength) and 'I feel that my arms and legs are thinner than they were in the past' (Thin)). The AUC was 0·77 (95 % CI 0·71, 0·83). With the optimal cut-off set at 3 or greater based on Youden's index, the sensitivity and the specificity were 76·1 and 63·6 %, respectively. In orthopaedic patients, our U-TEST scoring with two questions and two simple clinical variables can help to screen for sarcopenia.

How do we define and measure sarcopenia? A meta-analysis of observational studies

OBJECTIVE

this study aimed to investigate how sarcopenia has been defined and measured in the literature reporting its prevalence, and how different definitions and measurement tools can affect prevalence estimates.

DESIGN

systematic review and meta-analysis.

SETTING AND PARTICIPANTS

community-dwelling older people.

METHODS

meta-analysis of data collected from observational studies. We performed an electronic search in five databases to identify studies reporting the prevalence of sarcopenia. We used descriptive statistics to present data pertaining sarcopenia definition and measurement tools, and the quality-effects model for meta-analysis of pooled prevalence.

RESULTS

we found seven different operational definitions for sarcopenia and a variety of tools applied to assess the sarcopenic markers; muscle mass, muscle strength and physical performance. The prevalence of sarcopenia varied between the definitions with general estimates ranging from 5% based on the European Working Group on Sarcopenia in Older People (EWGSOP1) criterion to 17% with the International Working Group on Sarcopenia. According to the tool used to assess muscle mass, strength and physical performance, prevalence values also varied within definitions extending from 1 to 7%, 1 to 12% and 0 to 22%, respectively.

CONCLUSION AND IMPLICATIONS

the criteria used to define sarcopenia, as well as the measurement tools applied to assess sarcopenic markers have influence in the prevalence of sarcopenia. The establishment of a unique definition for sarcopenia, the use of methods that guarantee an accurate evaluation of muscle mass and the standardisation of measurement tools are necessary to allow a proper diagnosis and comparison of sarcopenia prevalence among populations.

The Association of Mitochondrial Copy Number With Sarcopenia in Adult Survivors of Childhood Cancer

BACKGROUND

Adult childhood cancer survivors are at risk for frailty, including low muscle mass and weakness (sarcopenia). Using peripheral blood mitochondrial DNA copy number (mtDNAcn) as a proxy for functional mitochondria, this study describes cross-sectional associations between mtDNAcn and sarcopenia among survivors.

METHODS

Among 1762 adult childhood cancer survivors (51.6% male; median age = 29.4 years, interquartile range [IQR] = 23.3-36.8), with a median of 20.6 years from diagnosis (IQR = 15.2-28.2), mtDNAcn estimates were derived from whole-genome sequencing. A subset was validated by quantitative polymerase chain reaction and evaluated cross-sectionally using multivariable logistic regression for their association with sarcopenia, defined by race-, age-, and sex-specific low lean muscle mass or weak grip strength. All statistical tests were 2-sided.

RESULTS

The prevalence of sarcopenia was 27.0%, higher among female than male survivors (31.5% vs 22.9%; P < .001) and associated with age at diagnosis; 51.7% of survivors with sarcopenia were diagnosed ages 4-13 years (P = .01). Sarcopenia was most prevalent (39.0%) among central nervous system tumor survivors. Cranial radiation (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 1.32 to 2.59) and alkylating agents (OR = 1.34, 95% CI = 1.04 to 1.72) increased, whereas glucocorticoids decreased odds (OR = 0.72, 95% CI = 0.56 to 0.93) of sarcopenia. mtDNAcn decreased with age (β = -0.81, P = .002) and was higher among female survivors (β = 9.23, P = .01) and among survivors with a C allele at mt.204 (β = -17.9, P = .02). In adjusted models, every standard deviation decrease in mtDNAcn increased the odds of sarcopenia 20% (OR = 1.20, 95% CI = 1.07 to 1.34).

CONCLUSIONS

A growing body of evidence supports peripheral blood mtDNAcn as a biomarker for adverse health outcomes; however, this study is the first to report an association between mtDNAcn and sarcopenia among childhood cancer survivors.

Toward the recognition and management of sarcopenia in routine clinical care

Sarcopenia, the age-associated decline in skeletal muscle mass and function, is a major cause of functional decline and mortality in older adults. Despite its importance, sarcopenia often remains unrecognized and inadequately managed in routine clinical care. A major hinderance to its clinical integration is the variation in diagnostic tools for sarcopenia. Diagnostic tools include those of the European Working Group on Sarcopenia in Older People (versions 1 and 2), those of the Asian Working Group for Sarcopenia (versions 1 and 2), and that of the Sarcopenia Definition and Outcomes Consortium. The management decision process of sarcopenia warrants an evaluation of risk factors such as a sedentary lifestyle, inadequate exercise, poor nutritional intake, smoking, depression and living circumstances. Herein, we provide an evidence-based update of the prevention and management of sarcopenia and propose practical information to facilitate the disease's adoption into routine care.

Objectively measured far vision impairment and sarcopenia among adults aged ≥ 65 years from six low- and middle-income countries

BACKGROUND

There are currently no studies on visual impairment and sarcopenia. We investigated the cross-sectional association between objectively measured far vision impairment and sarcopenia in a nationally representative sample of older adults aged 65 years and over from six low- and middle-income countries (LMICs).

METHODS

Cross-sectional, community-based data from the study on global ageing and adult health (SAGE) were analyzed. Far vision acuity was measured using the tumbling E LogMAR chart and classified as: no vision impairment (6/12 or better); mild vision impairment (6/18 or better but worse than 6/12); moderate vision impairment (6/60 or better but worse than 6/18); severe vision impairment (worse than 6/60). Sarcopenia was defined as having low skeletal muscle mass and either a slow gait speed or a weak handgrip strength. Associations were assessed with multivariable logistic regression.

RESULTS

Fourteen thousand five hundred and eighty five individuals aged ≥ 65 years were included in the analysis [mean (SD) age 72.6 (11.5) years; 54.1% females]. After adjustment for multiple potential confounders, compared to those with no vision impairment, the OR (95% CI) for sarcopenia in those with mild, moderate, and severe vision impairment were 1.10 (0.87-1.40), 1.69 (1.25-2.27), and 3.38 (1.69-6.77), respectively. The estimates for females and males were similar.

CONCLUSIONS

The odds for sarcopenia increased with increasing severity of far vision impairment among older people in LMICs. The mere co-occurrence of these conditions is concerning, and it may be prudent to implement interventions to address/prevent sarcopenia in those with far vision impairment through the promotion of physical activity and appropriate nutrition.

Malnutrition-sarcopenia syndrome and all-cause mortality in hospitalized older people

PURPOSE

Malnutrition-sarcopenia syndrome (MSS) describes the presence of sarcopenia and malnutrition together. This study aims to evaluate the relationship between MSS and all-cause mortality at two years in hospitalised older Turkish people.

METHODS

This is a bi-centered prospective cohort study conducted in older individuals in hospital settings (University hospital and research, research and training hospital). Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. Muscle mass was measured by bioelectrical impedance analysis. Malnutrition (MN) was assessed by the Mini Nutritional Assessment. Six study groups were formed according to sarcopenia and MN status; MSS, sarcopenia with malnutrition risk (MNR), sarcopenia, MN, MNR, and normal nutrition. The relationship between MSS and other study groups with mortality was assessed by Cox regression model. Survival curves were estimated using the Kaplan-Meier method.

RESULTS

350 hospitalised older people participated (mean age: 77.2 ± 7.6, 56% female). During the 2-year follow-up, 98 (28%) of the participants died. MSS, sarcopenia, sarcopenia with MNR and MN groups were independently associated with all-cause mortality at two years. MSS group had the highest hazard ratio (HR:19.8). Survival curves of MSS sarcopenia, sarcopenia with MNR, and MN groups were significantly different from MNR and normal nutrition groups. MSS had the worst survival curve.

CONCLUSIONS

Hospitalised older people should be evaluated for the presence of both sarcopenia and MN because of increased mortality. Preventive measures are needed for both conditions to decrease adverse health outcomes such as mortality.

Exercise in Aging: Be Balanced

The beneficial effects of exercise are recognized for preventing physical and cognitive decline during the aging process. However, there is still a gap concerning recommended intensity, volume, frequency and mode of exercise especially for older people. The aim of this study was to investigate an appropriate type of physical activity (PA) model for healthy aging. A commentary of the influence of PA and exercise on healthy aging through an online search of the databases Web of Science, PubMed and Google Scholar. Two living groups can be considered as potential references: modern hunter-gatherer small-scale population and master athletes. Greater physical activity is proposed for healthy aging than that recommended by WHO. Additionally, mindfulness meditation techniques during exercise are recommended especially for persons practicing long-duration exercises. Complex and compound exercise and workouts should include challenging exercises adjusted and balanced to provide clients, especially older people, with noticeable changes and progress.

Sarcopenia measurement in research and clinical practice

Sarcopenia is a disease related to accelerated loss of skeletal muscle and subsequent decline in functional capacity. It affects approximately 13% of the world's population aged over 60 years. Sarcopenia is primarily managed and prevented through a combination of exercise prescription combined with appropriate nutritional strategies. This review outlines diagnostic and case finding/screening tools for age-related (primary) sarcopenia used in research and clinical practice. Diagnostic tools critically reviewed include those of the: European Workgroup for Sarcopenia (EWGSOP) versions 1 and 2; Asian Working Group for Sarcopenia (AWGS) versions 1 and 2; Foundation for the National Institutes of Health (FNIH); and the Sarcopenia Definition and Outcomes Consortium (SDOC). Criteria used by diagnostic tools (muscle mass, muscle strength and physical functioning/performance) are also detailed. Case-finding tools include the SARC-F questionnaire, Ishii's formula and Goodman's screening grid. Additionally, this review discusses the strengths and weaknesses of each diagnostic and case-finding tool, and examines their ability to reliably predict adverse clinical outcomes and patient responses to potential therapies.

Differences among Three Skeletal Muscle Mass Indices in Predicting Non-Alcoholic Fatty Liver Disease: Korean Nationwide Population-Based Study

Recent studies have investigated the relationship between sarcopenia and non-alcoholic fatty liver disease (NAFLD); however, there is no unified definition of sarcopenia. Thus, we aimed to investigate the differences among three skeletal muscle mass indices (SMI) in predicting NAFLD. This study included 8133 adults from the 2008–2010 Korea National Health and Nutrition Survey. SMI was calculated as appendicular skeletal muscle mass divided by height-square (hSMI), weight (wSMI), or body mass index (bSMI). The presence of NAFLD was defined by using the NAFLD-liver fat score. On the receiver operating characteristic curve analysis, the predictive power of wSMI for NAFLD was significantly higher than those of hSMI and bSMI in men (wSMI vs. hSMI, p = 0.003; wSMI vs. bSMI, p < 0.001). In women, the predictive power of hSMI was only significantly higher than that of bSMI (p = 0.023), and other predictive powers were not significantly different. In addition, hSMI was correlated with insulin resistance and NAFLD-liver fat score in the opposite direction to wSMI and bSMI in both men and women. Among the three definitions of SMI, wSMI showed the highest diagnostic performance for predicting NAFLD in men, suggesting the importance of defining sarcopenia for its association with specific diseases.

SARC-F as a case-finding tool for sarcopenia according to the EWGSOP2. National validation and comparison with other diagnostic standards

BACKGROUND

Sarcopenia is a potentially reversible condition, which requires proper screening and diagnosis.

AIMS

To validate a Polish version of sarcopenia screening questionnaire (SARC-F), and assess its clinical performance.

METHODS

Cross-sectional validation study in community-dwelling subjects ≥ 65 years of age. Diagnosis of sarcopenia was based on the 2018 2nd European Working Group on Sarcopenia in Older People (EWGSOP2) consensus. Hand grip and 4-m gait speed were measured, and the Polish version of SARC-F was administered.

RESULTS

The mean (SD) age of 73 participants (21.9% men) was 77.8 (7.3) years. Seventeen participants (23.3%) fulfilled the EWGSOP2 criteria of sarcopenia, and 9 (12.3%) criteria for severe sarcopenia. Fourteen (19.2%) participants fulfilled the SARC-F criteria for clinical suspicion of sarcopenia. The Cronbach's alpha coefficient for internal was 0.84. With EWGSOP2 sarcopenia as a gold standard, the sensitivity of SARC-F was 35.3% (95% CI 14.2-61.7, p = 0.33), specificity was 85.7% (95% CI 73.8-93.6, p < 0.0001). The corresponding positive and negative predictive values were 42.9% (p = 0.79) and 81.4% (p < 0.0001), respectively. The probability of false-positive result was 14.3% (95% CI 6.4-26.2, p < 0.0001) and the probability of false-negative result was 64.7% (95% CI 38.3-85.8, p = 0.33). Overall the predictive power of SARC-F was low (c-statistic 0.64).

DISCUSSION

SARC-F is currently recommended for sarcopenia case finding in general population of older adults. However, its sensitivity is low, despite high specificity.

CONCLUSIONS

At present SARC-F is better suited to rule out sarcopenia then to case-finding. Further refinement of screening for sarcopenia with the use of SARC-F seems needed.