Metabolic Syndrome and Its Associations with Components of Sarcopenia in Overweight and Obese Older Adults

Sarcopenia prevalence using handgrip strength or chair stand performance in adults living with type 2 diabetes mellitus

BACKGROUND

The updated European Working Group on Sarcopenia in Older People (EWGSOP2) recommends handgrip strength (HGS) and the chair stand test (CST) to assess muscle strength, with the CST being a convenient proxy for lower limb strength. However, adiposity may differentially influence these strength criteria and produce discrepant sarcopenia prevalence.

OBJECTIVE

To determine the prevalence of sarcopenia using HGS or the CST, and to investigate the associations between these strength criteria and adiposity in adults with type 2 diabetes mellitus.

METHODS

The EWGSOP2 definition was used to assess the prevalence of probable (low muscle strength), confirmed (plus low muscle mass) and severe (plus poor physical performance) sarcopenia. Linear regression models were used to study the association between different measures of muscle strength and adiposity.

RESULTS

We used data from 732 adults with type 2 diabetes mellitus (35.7% female, aged 64 ± 8 years, body mass index 30.7 ± 5.0 kg/m2). Using the CST compared with HGS produced a higher prevalence of probable (31.7% vs. 7.1%), confirmed (5.6% vs. 1.6%) and severe (1.0% vs. 0.3%) sarcopenia, with poor agreement between strength criteria to identify probable sarcopenia. CST performance, but not HGS, was significantly associated with all measures of adiposity in unadjusted and adjusted models.

CONCLUSIONS

Higher levels of adiposity may impact CST performance, but not HGS, resulting in a higher prevalence of sarcopenia in adults with type 2 diabetes mellitus. Consideration should be paid to the most appropriate measure of muscle function in this population.

Incidence of a Multicomponent Physical Exercise Program on Body Composition in Overweight or Obese People Aged 60 Years or Older from Chile

This research aimed to explore the changes produced in body mass index (BMI), fat mass percentage (FMP), muscle mass percentage (MMP), and visceral fat percentage (VFP) in 60-year-old or over overweight or obese people after a multicomponent exercise program. This quasi-experimental study involved 70 overweight or obese older people between 60 and 86 years old (M = 73.15; SD = 5.94) who were randomly assigned to a control group (CG, n = 35) and an experimental group (EG, n = 35). At the beginning and at the end of the intervention program, anthropometric and body composition data were collected. The results showed an increase in BMI after the intervention in the CG (p = 0.010) and a decrease in the EG (p < 0.001). The results regarding the FMP indicate a significant decrease in the EG (p < 0.001) after the intervention, as occurs with the VFP (p = 0.003). The MMP increased in the EG (p < 0.001) after the intervention program. Regarding gender, statistically significant differences were found in the MMP after the intervention (p = 0.025), with higher percentages in men in the EG. VFP decreased in both men (p = 0.005) and women (p = 0.019) in the EG. From the results obtained, we can say that a 6-month multicomponent program produces a decrease in BMI, FMP, and VFP and an increase in MMP in its participants. This type of intervention seems to produce a greater increase in muscle mass in men than in women and a decrease in VFP in both genders.

Conflicting Associations among Bioelectrical Impedance and Cardiometabolic Health Parameters in Young White and Black Adults

PURPOSE

The purpose of this cross-sectional evaluation was to determine the associations between raw bioelectrical impedance and cardiometabolic health parameters in a sample of young non-Hispanic White and African American adults.

METHODS

A total of 96 (female: 52, male: 44) non-Hispanic White ( n = 45) and African American adults ( n = 51) between the ages of 19 and 37 yr (22.7 ± 3.83 yr) completed several fasted assessments including resting systolic blood pressure (rSBP), blood glucose (FBG), blood lipids, and bioelectrical impedance spectroscopy. Bioelectrical impedance spectroscopy-derived measurements included phase angle, bioimpedance index (BI), impedance ratio (IR), reactance index (XCi), fat-free mass (FFM), FFM index (FFMi), and absolute (a) and relative (%) total body water (TBW) and extracellular (ECF) and intracellular fluid (ICF). All bioelectric variables were collected at 50 kHz other than IR (250 kHz/5 kHz). Multiple regressions were conducted and adjusted for sex, age, and body mass index.

RESULTS

rSBP was positively, and HDL was inversely, associated with all bioelectrical impedance and absolute hydration variables (all P ≤ 0.050) other than XCi for rSBP and XCi and FFMi for HDL. rSBP ( P < 0.001) was inversely, and HDL ( P = 0.034) was positively, associated with IR. FBG was positively associated with BI, XCi, FFM, TBWa, and ECFa (all P < 0.050). Metabolic syndrome severity was positively associated with BI, FFM, TBWa, and ECFa for women (all P ≤ 0.050) and with ICFa for African American women ( P = 0.016).

CONCLUSIONS

Given the rapid increase in the prevalence of cardiometabolic health risks among young adults and the broad use of bioelectrical impedance in practice, the conflicting associations we observed in this age group suggest that bioelectrical impedance parameters should be used with caution in the context of cardiometabolic health risks and age.

Association of low muscle mass and obesity with increased all-cause and cardiovascular disease mortality in US adults

BACKGROUND

Sarcopenic obesity, defined as the coexistence of low muscle mass and high adiposity, is associated with cardiovascular disease (CVD) and mortality. However, to what extent sarcopenia contributes to these risks independently or in conjunction with other cardiovascular risk factors remains unclear. This study aimed to investigate the association of low muscle mass, central obesity (COB), metabolic abnormalities, and their combinations with CVD and mortality risk.

METHODS

This cross-sectional analysis used data from the National Health and Nutrition Examination Survey 1999-2006 and 2011-2018. Participants aged >20 years and with reported whole-body dual X-ray absorptiometry data were included. Participants were divided into eight groups based on low muscle mass, metabolic abnormalities, and COB status.

RESULTS

The mean age of participants was 55 years, and 50.4% of participants were male. Low muscle mass was observed in 2472 (14.6%) out of 16 839 participants. Among the eight groups, the metabolically unhealthy COB group with low muscle mass had the highest hazard ratio (HR) for all-cause mortality (HR, 2.00; 95% CI, 1.56-2.56; P < 0.001), whereas the metabolically healthy COB group with low muscle mass had the highest HR for CVD mortality (HR, 3.18; 95% CI, 1.53-6.65; P = 0.001). The mediation analysis showed that low muscle mass directly increased the risk of both all-cause mortality (HR, 1.56; 95% CI, 1.35-1.79; P < 0.001) and CVD mortality (HR, 1.80; 95% CI, 1.40-2.31; P < 0.001). Additionally, subgroup analysis revealed that low muscle mass significantly increased the risk of all-cause and CVD mortality in participants without a prior CVD history and those with diabetes mellitus.

CONCLUSIONS

Low muscle mass is an independent risk factor for all-cause and CVD mortality, especially in individuals with metabolic abnormalities and COB.

Mid-arm muscle circumference and triceps skinfold thickness associated with cardiometabolic disease in Chinese residents: A prospective cohort study

BACKGROUND AND AIMS

The association of cardiometabolic disease (CMD) with body muscle and fat mass remains unclear. Mid-arm muscle circumference (MAMC) and triceps skinfold (TSF) thickness are easily obtained measuring methods for these two body compositions. This study aimed to investigate the association of CMD with MAMC and TSF thickness among Chinese residents.

METHODS

A total of 9440 eligible participants from the China Health and Nutrition Survey were included in the analysis. Associations of CMD prevalence with MAMC and TSF thickness were estimated using logistic regression models. Multivariable COX proportional-hazards regression models were used to estimate the effect of baseline MAMC and TSF thickness on subsequent CMD.

RESULTS

Positive associations of CMD prevalence with MAMC (odds ratio [OR] = 1.169, 95% confidence interval [CI] 1.110-1.232, P < 0.001) and TSF thickness (OR = 1.313, 95%CI 1.240-1.390, P < 0.001) were observed in the cross-sectional analysis. In the longitudinal study, a 1-SD increase in MAMC was associated with a 13.6% increased risk of CMD incidence (hazard ratio [HR] = 1.136, 95%CI 1.073-1.204, P < 0.001), and a 1-SD increase in TSF thickness had a 17.6% increased risk of CMD incidence (HR = 1.176, 95%CI 1.084-1.276, P < 0.001). For the CMD components, both MAMC and TSF thickness contributed to increased incidences of hypertension (HR = 1.163, 95%CI 1.097-1.233, P < 0.001 in MAMC; HR = 1.218, 95%CI 1.110-1.336, P < 0.001 in TSF thickness) and diabetes mellitus (HR = 1.166, 95%CI 1.028-1.323, P = 0.017 in MAMC; HR = 1.352, 95%CI 1.098-1.664, P = 0.004 in TSF thickness).

CONCLUSIONS

Individuals with higher MAMC and TSF thickness had an increased incidence of CMD, mainly hypertension and diabetes mellitus. This study revealed a seemingly counterintuitive association between body muscle mass and metabolic homeostasis. Although the potential mechanisms require further exploration, the impact of body muscle mass on metabolic health cannot be ignored.

A comprehensive review on the risks assessment and treatment options for Sarcopenia in people with diabetes

Objectives

This comprehensive review aims to examine the reciprocal interplay between Type 2 diabetes mellitus (T2DM) and sarcopenia, identify prevailing research gaps, and discuss therapeutic approaches and measures to enhance healthcare practices within hospital settings.

Methods

A thorough literature review was conducted to gather relevant studies and articles on the relationship between T2DM and sarcopenia. Various databases were searched, including Google Scholar, PubMed, Scopus, and Science Direct databases. The search terms included T2DM, sarcopenia, inflammation, insulin resistance, advanced glycation end products, oxidative stress, muscle dimensions, muscle strength, muscle performance, aging, nutrition, hormone levels, and physical activity. The collected articles were critically analysed to extract key findings and identify gaps in current research.

Results

The prevalence and incidence of metabolic and musculoskeletal disorders, notably T2DM and sarcopenia, have surged in recent years. T2DM is marked by inflammation, insulin resistance, accumulation of advanced glycation end products, and oxidative stress, while sarcopenia involves a progressive decline in skeletal muscle mass and function. The review underscores the age-related correlation between sarcopenia and adverse outcomes like fractures, falls, and mortality. Research gaps regarding optimal nutritional interventions for individuals with T2DM and sarcopenia are identified, emphasizing the necessity for further investigation in this area.

Conclusions

The reciprocal interplay between T2DM and sarcopenia holds significant importance. Further research is warranted to address knowledge gaps, particularly in utilizing precise measurement tools during clinical trials. Lifestyle modifications appear beneficial for individuals with T2DM and sarcopenia. Additionally, practical nutritional interventions require investigation to optimize healthcare practices in hospital settings.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01262-w.

Sarcopenia and type 2 diabetes: Pathophysiology and potential therapeutic lifestyle interventions

AIMS

Sarcopenia generally refers to the age-related reduction in muscle strength, functional ability, and muscle mass. Sarcopenia is a multifactorial condition associated with poor glucose disposal, insulin resistance, and subsequently type 2 diabetes (T2D). The pathophysiological connection between sarcopenia and T2D is complex but likely involves glycemic control, inflammation, oxidative stress, and adiposity.

METHODS AND RESULTS

Resistance exercise and aerobic training are two lifestyle interventions that may improve glycemic control in older adults with T2D and counteract sarcopenia. Further, there is evidence that dietary protein, Omega-3 fatty acids, creatine monohydrate, and Vitamin D hold potential to augment some of these benefits from exercise.

CONCLUSIONS

The purpose of this narrative review is: (1) discuss the pathophysiological link between age-related sarcopenia and T2D, and (2) discuss lifestyle interventions involving physical activity and nutrition that may counteract sarcopenia and T2D.

Prevalence of Sarcopenia in Africa: A Systematic Review

Objective

The world population gradually getting older, age-related sarcopenia is becoming more frequent. Known to be highly prevalent in high income countries, relative data in Africa are still scarce. This review aims to estimate the prevalence of sarcopenia in Africa and its characteristics.

Study Design and Setting

A literature search in PubMed, Web of Science, Google Scholar, and Scopus was conducted in October 2022. All studies reporting the prevalence of sarcopenia in Africa within 15 years were included, and we did an assessment of bias with Hoy et al's risk bias assessment tool. The estimated prevalence of sarcopenia was the outcome and we performed secondary analyses by age, gender, and diagnostic criteria. The random effect model was used for the prevalence estimation. The prevalence of sarcopenia and 95% confidence interval (95% CI) were calculated using the inverse-variance method.

Results

A total of 17 studies met our eligibility criteria, for a study population of 12,690 participants with 44.3% males and 55.7% females. The overall prevalence of sarcopenia was 25% (95% CI: 19-30%). The prevalence of sarcopenia among 50 years old and older was 23% (95% CI: 17-29%). We had a higher prevalence of sarcopenia among males (30%, %95 IC: 20-39%) than females (29%, %95 IC: 21-36%). The prevalence of sarcopenia was different depending on the diagnosis criteria used.

Conclusion

The prevalence of sarcopenia in Africa was relatively high. However, the fact that the majority of included studies were hospital-based studies shows the necessity of further community-based studies in order to have a more accurate representation of the situation in the general population.

The role of skeletal muscle mass on cardiovascular disease risk: an emerging role on modulating lipid profile

PURPOSE OF REVIEW

The purpose of this review was to present updated evidence on the role of skeletal muscle mass on cardiometabolic health.

RECENT FINDINGS

Increased lean, and especially skeletal, muscle mass has been associated with better cardiometabolic health in various epidemiological studies, even in younger age groups. In addition, the link between skeletal muscle mass and adult lipid profile is of interest. A preliminary analysis using the data from the ATTICA prospective cohort study (2002-2022) supports this association.

SUMMARY

Skeletal muscle mass has many metabolic functions (i.e., glucose, insulin and protein metabolism, mitochondrial function, arterial stiffness, inflammation, oxidative stress, brain function, hormone status). Given its associations with the lipid profile and overall cardiometabolic risk, skeletal muscle mass stands among the emerging risk factors for cardiovascular diseases. In addition to only using body mass index or fat distribution, more studies should evaluate lean mass and its prognostic and predictive ability regarding chronic diseases.

Muscle Quality Index in Morbidly Obesity Patients Related to Metabolic Syndrome Markers and Cardiorespiratory Fitness

BACKGROUND

Muscle quality index (MQI) is an emerging health indicator obtained by dividing handgrip strength by body mass index (BMI) that needs to be studied in morbidly obese patients (defined by BMI ≥ 35 kg/m²).

OBJECTIVE

To determine the association between MQI, metabolic syndrome (MetS) markers, and cardiorespiratory fitness (CRF), and as a second objective to determine the potential mediation role of MQI in the relationship between abdominal obesity and systolic blood pressure (SBP) in this sample.

METHODS

This cross-sectional study included 86 severely/morbidly obese patients (age = 41.1 ± 11.9 y, nine men). MQI, metabolic syndrome markers, CRF, and anthropometric parameters were measured. Two groups were developed according to MQI; High-MQI (n = 41) and Low-MQI (n = 45).

RESULTS

The Low-MQI group reported higher abdominal obesity (High-MQI: 0.7 ± 0.1 vs. Low-MQI: 0.8 ± 0.1 WC/height; p = 0.011), SBP (High-MQI: 133.0 ± 17.5 vs. Low-MQI: 140.1 ± 15.1 mmHg; p = 0.048), and lower CRF (High-MQI; 26.3 ± 5.9 vs. Low-MQI; 22.4 ± 6.1 mL/kg/min, p = 0.003) than the High-MQI group. Waist-to-height ratio (β: -0.07, p = 0.011), SBP (β: -18.47, p = 0.001), and CRF (β: 5.21, p = 0.011) were linked to MQI. In a mediation model, the indirect effect confirms that MQI is a partial mediator of the association between abdominal obesity with SBP.

CONCLUSIONS

MQI in morbidly obesity patients reported an inverse association with MetS markers and a positive association with CRF (VO2_max). It mediates the relationship between abdominal obesity and SBP.

Lithium-Induced Optimization Mechanism for an Ultrathin-Strut Biodegradable Zn-Based Vascular Scaffold

To reduce incidences of in-stent restenosis and thrombosis, the use of a thinner-strut stent has been clinically proven to be effective. Therefore, the contemporary trend is toward the use of ultrathin-strut (≤70 µm) designs for durable stents. However, stents made from biodegradable platforms have failed to achieve intergenerational breakthroughs due to their excessively thick struts. Here, microalloying is used to create an ultrathin-strut (65 µm) zinc (Zn) scaffold with modified biodegradation behavior and improved biofunction, by adding lithium (Li). The scaffold backbone consists of an ultrafine-grained Zn matrix (average grain diameter 2.28 µm) with uniformly distributed nanoscale Li-containing phases. Grain refinement and precipitation strengthening enable it to achieve twice the radial strength with only 40% of the strut thickness of the pure Zn scaffold. Adding Li alters the thermodynamic formation pathways of products during scaffold biodegradation, creating an alkaline microenvironment. Li₂ CO₃  may actively stabilize this microenvironment due to its higher solubility and better buffering capability than Zn products. The co-release of ionic zinc and lithium enhances the beneficial differential effects on activities of endothelial cells and smooth muscle cells, resulting in good endothelialization and limited intimal hyperplasia in porcine coronary arteries. The findings here may break the predicament of the next-generation biodegradable scaffolds.

Association of high body mass index, waist circumference, and body fat percentage with sarcopenia in older women

BACKGROUND

Age-related obesity and body composition changes include loss of muscle mass and increased body fat. This study aimed to investigate sex differences in the impact of sarcopenia, defined by the Asian Working Group for Sarcopenia (AWGS), on obesity in Korean older adults.

METHODS

In this 2-year longitudinal study, 3014 participants were excluded based on AWGS sarcopenia parameters (if any one of the sarcopenic parameter criteria was satisfied), including low handgrip strength (HGS), low appendicular skeletal muscle mass index (ASMI), and low short physical performance battery (SPPB). A total of 926 non-sarcopenic participants were recruited for the study. The obese and non-obese groups were compared according to the sarcopenia parameters. The following variables were selected for obesity analysis: body mass index (BMI), waist circumference (WC), and body fat percentage. Unadjusted and fully adjusted logistic regression analyses were performed for each variable to predict sarcopenia and sarcopenic obesity according to sex.

RESULTS

Among the sarcopenia parameters, reduction in ASMI was significantly lower in the obese group with high WC and percentage of body fat (PBF) in both men and women (P < 0.01). Multivariable analysis revealed that different obesity parameters were associated with AWGS criteria: women in the high BMI group presented significantly lower ASMI and sarcopenia (ASMI, OR = 0.289, 95% CI = 0.174-0.480; sarcopenia, OR = 0.152, 95% CI = 0.048-0.483). Women in the high WC group had significantly lower ASMI and sarcopenia (ASMI, OR = 0.307, 95% CI = 0.189-0.500; sarcopenia, OR = 0.262, 95% CI = 0.106-0.649). Women in the high PBF group had a lower incidence of sarcopenia (OR = 0.214, 95% CI = 0.068-0.278).

CONCLUSIONS

Our study identified that high BMI had a protective effect on the reduction of muscle mass in men and women. However, obesity parameters including BMI, WC, and PBF were positively correlated with a lower incidence of sarcopenia only in women. Obesity in older women may have a protective effect in reducing ASMI and the incidence of sarcopenia.

Changes in the body composition of boys aged 11-18 years due to COVID-19 measures in the Czech Republic

BACKGROUND

The lockdown measures related to coronavirus disease 2019 (COVID) impacted the health of adolescents by reducing physical activity (PA). The physical changes in response to decreases in PA can be measured with full body composition analysis. The aim of this study was to evaluate the effects of long-term PA restrictions on body fat (BF), fat-free mass (FFM) and skeletal muscle mass (SMM) in adolescents.

METHODS

A total of 1669 boys (before PA restriction (G1): 998; after PA restrictions ended (G2): 671; between the ages of 11 and 18 were included. The measured parameters were body mass (BM), visceral fat area (VFA), BF, FFM and SMM. The whole-body composition was evaluated using bioelectrical impedance analysis (BIA).

RESULTS

Compared to G1, G2 exhibited an increase in BF between 1.2 and 5.1%. This difference was significant in boys aged 13 to 18 years (p < 0.05). VFA increased between 5.3 and 20.5 cm²; this increase was significant in boys aged 13 to 18 years (p < 0.05). SMM decreased between 2.6 and 3.8%, and this decrease was significant in all age groups (p < 0.05). Changes in body composition were not accompanied by any significant changes in BM.

CONCLUSIONS

COVID-19 restrictions reduced PA, resulting in a significant decrease in SMM. This decrease may impact boys' ability to engage in sufficiently varied PA, which may lead to a further decline in PA and subsequent medical consequences in adulthood.

Association between handgrip strength and metabolic syndrome: A meta-analysis and systematic review

BACKGROUND

Although muscle strength has been reported to be associated with metabolic syndrome (MetS), the association is still controversial. Therefore, the purpose of this meta-analysis was to identify the association between handgrip strength (HGS) and MetS.

METHODS

Original research studies involving HGS and MetS from database inception to 20 May 2022 were selected from PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang databases, and Chinese Biomedical Document Service System. The odds ratios (ORs) with 95% confidence intervals (CIs) of MetS for HGS were calculated using a random-effects model. A dose-response analysis was performed. Subgroup analysis and meta-regression were also conducted.

RESULTS

Thirty effect sizes (reported in 19 articles) with a total of 43,396 participants were included in this meta-analysis. All studies were considered to be of moderate-to-good quality. An inverse association between HGS (low vs. high) with MetS was shown (OR: 2.59, 95% CI: 2.06-3.25). Subgroup analyses demonstrated the pooled ORs of relative HGS (HGS/weight), relative HGS (HGS/BMI), and absolute HGS were 2.97 (95% CI: 2.37-3.71), 2.47 (95% CI: 1.08-5.63), and 1.34 (95% CI: 1.06-1.68), respectively. Dose-response analysis revealed a significant linear dose-response relationship between relative HGS (HGS/weight) and MetS in observational studies (0.1 HGS/weight: OR, 0.68; 95% CI: 0.62-0.75). Univariate meta-regression analysis indicated that country status, measuring tools of HGS, components of MetS, and diagnosed criteria of MetS explained 16.7%, 26.2%, 30.1%, and 42.3% of the tau-squared in the meta-regression, respectively.

CONCLUSION

The results of the current meta-analysis indicated that lower HGS is associated with a higher risk of MetS. A linear dose-response association between lower relative HGS (HGS/weight) and increased prevalence of MetS was found. Accordingly, a lower HGS is a significant predictor of MetS.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021276730].

Association between skeletal muscle mass or percent body fat and metabolic syndrome development in Japanese women: A 7-year prospective study

Previous cross-sectional studies have indicated that low relative appendicular lean mass (ALM) against body weight (divided by body weight, ALM/Wt, or divided by body mass index, ALM/BMI) was negatively associated with metabolic syndrome (MetS). Conversely, previous cross-sectional studies have indicated that the absolute ALM or ALM divided by squared height (ALM/Ht2) were positively associated with MetS. The aim of this longitudinal study was to investigate the association between low absolute or relative skeletal muscle mass, leg muscle power, or percent body fat and the development of MetS in Japanese women in a 7-y prospective study. The study participants included 346 Japanese women aged 26 to 85 years. The participants were divided into low and high groups based on the median values of ALM/Wt, ALM/BMI, ALM/Ht2, absolute ALM, or leg power. The longitudinal relationship between ALM indices or leg power and MetS development was examined using Kaplan-Meier curves and Cox regression models (average follow-up duration 7 years, range 1 to 10 years). During follow-up, 24 participants developed MetS. MetS incidence was higher in the low ALM/Wt group than the high ALM/Wt group even after controlling for age, obesity, waist circumference, family history of diabetes, smoking, and physical activity [adjusted hazard ratio = 5.60 (95% CI; 1.04-30.0)]. In contrast, MetS incidence was lower in the low ALM/Ht2 group than the high ALM/Ht2 group [adjusted hazard ratio = 10.6 (95%CI; 1.27-89.1)]. MetS incidence was not significantly different between the low and high ALM/BMI, absolute ALM, and leg power groups. Both ALM/Ht2 and ALM/Wt were not significant predictive variables for MetS development when fat mass or percent body fat was taken into account in the Cox model. At the very least, the results of this study underscore the importance of body composition measurements in that percent body fat, but not ALM, is associated with MetS development.

Sex Difference in Cutoff and Prevalence of Sarcopenia among 300,090 Urban Korean Population: Association with Metabolic Syndrome

Background and Objectives: The study aimed to establish the threshold values and prevalence of sarcopenia and to investigate the association of sarcopenia with metabolic syndrome in an urban Korean population. Materials and Methods: The study included 300,090 adults who underwent anthropometric analyses by bioelectrical impedance analyzer. Sarcopenia was defined as: (1) class I, skeletal muscle mass index (SMI) within −1 to −2 standard deviations (SDs); (2) or class II, <−2 SD of SMI in a young population. Results: Low SMI threshold levels for class I and class II sarcopenia were 39.8 and 36.7% in men, and 35.5 and 32.3% in women. Among all age groups, the prevalence rates of sarcopenia were highest in the age group 80−89 years. Following adjustment for possible confounders including age, sex, height, metabolic and health behavioral factors, adjusted odds ratios (95% confidence intervals) for the risk of metabolic syndrome were 2.43 (2.33−2.54) for class I and 2.69 (2.49−2.91) for class II sarcopenia, compared with the normal reference. Sarcopenia was more strongly associated with metabolic syndrome in women than men (p for interaction < 0.01). The threshold values and prevalence of sarcopenia were demonstrated in a large Korean urban population. Conclusions: This study identified that sarcopenia was associated with increased risk of metabolic syndrome, showing itself to be significantly higher in women than men.

Exploring the relationships between anthropometric indices of adiposity and physical performance in middle-aged and older Brazilian women: a canonical correlation analysis

OBJECTIVES

This study analyzed the influence of anthropometric indices of adiposity on the physical performance of middle-aged and older women.

METHODS

A cross-sectional study was conducted among 368 women from 50 years to 80 years old. Anthropometric and biochemical characteristics were analyzed, and physical performance was evaluated. The statistical analysis used measures of central tendency and dispersion for descriptive data, Pearson correlations to demonstrate the initial associations between the variables, and canonical correlation (CC) to evaluate the relationship between the set of anthropometric adiposity indices and performance-related variables.

RESULTS

The participants had a mean age of 58.57±8.21 years, a visceral adiposity index of 7.09±4.23, a body mass index of 29.20±4.94 kg/m2, and a conicity index of 1.33±0.07. The average handgrip strength was 25.06±4.89 kgf, gait speed was 1.07±0.23 m/s, and the mean Short Physical Performance Battery (SPPB) score was 10.83±1.36. The first canonical function presented the highest shared variance, CC, and redundancy index (cumulative percentage of variance, 82.52; Wilks' lambda, 0.66; CC, 0.532; p<0.001). From the analysis of this canonical function, the conicity index (-0.59) displayed inverse correlations with handgrip strength (0.84) and the SPPB (0.68), as well as a direct correlation with gait speed (-0.43).

CONCLUSIONS

In middle-aged and older women, there was an inverse relationship between the conicity index and muscle strength and power, while a direct relationship was found between the same index and gait speed.

Exercise, aerobic fitness, and muscle strength in relation to glucose tolerance 6 to 10 years after gestational diabetes

AIMS

We sought to identify self-reported exercise and objectively measured fitness variables associated with glucose tolerance and metabolic health 6-10 years after gestational diabetes (GDM) METHODS: Women (n = 84) underwent oral glucose tolerance testing (OGTT), body composition measurements, and lifestyle questionnaires 6 and 10 years after GDM. In a subset (n = 45), peak oxygen uptake (VO_2peak), peak fat oxidation, and maximal isometric strength of five muscle groups were tested.

RESULTS

At 10 years, 41 women (49%) had impaired glucose metabolism or type 2 diabetes (T2D). VO_2peak and muscle strength were lowest in the T2D group. In a regression analysis, VO_2peak and all strength measurements were associated negatively with HbA1c and waist-hip ratio and positively with high-density lipoprotein cholesterol. However, only muscle strength was associated with fasting and area-under-the-curve glucose. For changes between the 6- and 10-year follow-ups, only muscle strength was associated with HbA1c change, whereas both VO_2peak and strength were associated with high-density lipoprotein level and changes in waist-hip ratio. Peak fat oxidation and self-reported physical activity showed no or weak relationships with glycemic variables.

CONCLUSION

Objectively measured fitness variables, particularly muscle strength, were strongly associated with glycemic and other metabolic outcomes in a high-risk group after GDM.

Prevalence of Risk of Sarcopenia in Polish Elderly Population—A Population Study

Sarcopenia in the elderly population is a public health challenge, and there are few data on its prevalence in Europe. In this study, we investigated the prevalence of sarcopenia in the elderly Polish population and its association with the level of obesity and co-existing diseases. We conducted a population-based cross-sectional study involving 823 men and 1177 women aged 65 years and older, randomly selected from the population living in the territory of the Republic of Poland between 2017 and 2020. We analyzed the results of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). Risk of sarcopenia was assessed with the simple questionnaire to rapidly diagnose sarcopenia (SARC-F), and sarcopenic obesity risk was defined as the combination of anthropometry and SARC-F results. In addition, we collected disease data with an author questionnaire. The prevalence of risk of sarcopenia was 18.6% (22.3% in women and 13.2% in men), and its incidence significantly increased with age in both sexes. The risk of sarcopenic obesity was more common in women than in men, and it was higher in the older age group, except for sarcopenic obesity diagnosed by the WHR criteria. The group of elderly with concomitant diseases had a higher risk of developing sarcopenia, which emphasizes the need to monitor sarcopenia when concomitant diseases are diagnosed. In both groups, risk of sarcopenia was associated with motor and respiratory system diseases, type 2 diabetes, and neurological diseases. This study highlights that the risk of sarcopenia in the elderly population affects women to a greater extent than men. It is important to identify the elderly at risk of sarcopenia in routine clinical practice to develop long-term prevention strategies.

Effect of vitamin D monotherapy on indices of sarcopenia in community-dwelling older adults: a systematic review and meta-analysis

BACKGROUND

Vitamin D supplementation is proposed as a potentially effective nutritional intervention to mitigate the risk of sarcopenia. The aim of this systematic review and meta-analysis was to investigate the impact of vitamin D supplementation monotherapy on indices of sarcopenia in community-dwelling older adults.

METHODS

A comprehensive search of the literature was conducted in PubMed, Web of Science, Scopus, and Cochrane Library. Eligible randomized controlled trials (RCTs) compared the effect of vitamin D supplementation (as monotherapy) with placebo on indices of sarcopenia in older (>50 years) adults. Using the random effects inverse-variance model, we calculated the mean difference (MD) in handgrip strength (HGS), short physical performance battery (SPPB), timed up and go (TUG), and appendicular lean mass (ALM) between groups. We also calculated the standardized mean difference (SMD) in general muscle strength and general physical performance (composite plot of all muscle strength and physical performance outcomes, respectively) between groups.

RESULTS

Ten RCTs were included in the meta-analysis. A significant decrease in SPPB scores was observed with vitamin D supplementation compared with placebo (MD: -0.23; 95% CI -0.40 to -0.06; I²  = 0%; P = 0.007). Vitamin D supplementation conferred no effect on HGS (MD: -0.07 kg; 95% CI -0.70 to 0.55; I²  = 51%, P = 0.82), TUG (MD: 0.07 s; 95% CI -0.08 to 0.22; I²  = 0%, P = 0.35), ALM (MD: 0.06 kg/m² ; 95% CI: -0.32 to 0.44; I²  = 73%, P = 0.77), general muscle strength (SMD: -0.01; 95% CI -0.17 to 0.15; I²  = 42%, P = 0.90), or general physical performance (SMD: -0.02; 95% CI -0.23 to 0.18; I²  = 71%, P = 0.83).

CONCLUSIONS

Vitamin D supplementation did not improve any sarcopenia indices in community-dwelling older adults and may compromise some aspects of physical performance. Future studies are warranted to investigate the impact of vitamin D supplementation on individual indices of SPPB, including mobility and balance, in older adults.

A combined index of waist circumference and muscle quality is associated with cardiovascular disease risk factor accumulation in Japanese obese patients: a cross-sectional study

PURPOSE

To identify obese patients at high risk of cardiovascular disease (CVD) using a combined index of obesity and sarcopenia.

METHODS

In this cross-sectional study, we firstly conducted analysis of covariance to select each index most associated with the CVD risk score, the number of concomitant CVD risk factors, among obesity- (body mass index, percentage body fat, or waist circumference [WC]) and sarcopenia-evaluated indices (skeletal muscle mass index, handgrip strength, or muscle quality [MQ]), respectively in 188 Japanese obese patients (BMI ≥ 25 kg/m², 73 men and 115 women). Next, we conducted multivariate logistic regression analysis to compare the four groups (Group A-D) classified by medians of the selected indices.

RESULTS

WC and MQ were selected as the indices most associated with the CVD risk scores, respectively. The CVD risk score was significantly higher in Group B (low WC and low MQ) and Group D (high WC and low MQ) with higher prevalence of diabetes as compared with Group A (low WC and high MQ). Adjusted for sex and age, odds ratios for CVD risk scores = 2 were significantly higher in Group B, Group C (high WC and high MQ), and Group D compared with Group A. Furthermore, odds ratios for CVD risk scores = 3 were significantly higher only in Group D compared with Group A (4.29 [95% confidence interval: 1.49-12.33], p = 0.007).

CONCLUSION

Combined index of WC and MQ was useful in Japanese obese patients at high risk of CVD, regardless sex and age.

Skeletal muscle properties show collagen organization and immune cell content are associated with resistance exercise response heterogeneity in older persons

In older individuals, hypertrophy from progressive resistance training (PRT) is compromised in approximately one- third of participants in exercise trials. The objective of this study was to establish novel relationships between baseline muscle features and/or their PRT-induced change in vastus lateralis muscle biopsies with hypertrophy outcomes. Multiple linear regression analyses adjusted for sex were performed on phenotypic data from older adults (n=48, 70.8±4.5 years) completing 14 weeks of PRT. Results show that baseline muscle size associates with growth regardless of hypertrophy outcome measure (fiber cross-sectional area (fCSA), β=-0.76, Adj. p<0.01; thigh muscle area by CT, β=-0.75, Adj. p<0.01; DXA thigh lean mass, β=-0.47, Adj. p<0.05). Furthermore, loosely packed collagen organization (β=-0.44, Adj. p<0.05) and abundance of CD11b+/CD206- immune cells (β=-0.36, Adj. p=0.10) were negatively associated with whole muscle hypertrophy, with a significant sex interaction on the latter. Additionally, a composite hypertrophy score generated using all three measures reinforces significant fiber level findings that changes in myonuclei (β=0.67, Adj. p<0.01), changes in immune cells (β=0.48, Adj. p<0.05; both CD11b+/CD206+ and CD11b+/CD206- cells), and capillary density (β=0.56, Adj. p<0.01) are significantly associated with growth. Exploratory single cell RNA-sequencing of CD11b+ cells in muscle in response to resistance exercise showed that macrophages have a mixed phenotype. Collagen associations with macrophages may be an important aspect in muscle response heterogeneity. Detailed histological phenotyping of muscle combined with multiple measures of growth response to resistance training in older persons identify potential new mechanisms underlying response heterogeneity and possible sex differences.

Should knee extension strength testing be implemented as a screening test for identifying probable and confirmed sarcopenia in older T2DM patients?

Background

The accelerated loss of muscle strength and mass observed in older type 2 diabetes mellitus (T2DM) patients due to the combined effects of diabetes and obesity, greatly increases their risk for sarcopenia. Early detection and treatment of probable and confirmed sarcopenia is paramount to delay mobility disability. Using low handgrip strength cut-off points for the initial identification of sarcopenia according to the new European Working Group on Sarcopenia in Older People (EWGSOP2) guidelines may mask the presence of sarcopenia. Relative knee extension strength cut-off points using a simple hand-held dynamometer can assist clinicians in the diagnosis of probable and confirmed sarcopenia by possibly reducing false negative results.

Methods

A cohort of one hundred T2DM older patients (60% women) (mean age 74.5 years) mostly obese community dwelling older adults were evaluated for body composition by Bioelectrical impedance analysis (BIA), yielding appendicular skeletal mass index (ASMI) results. Patients underwent handgrip strength (HGS) and knee extension strength (KES) tests as well as functional ability tests. Prevalence of probable and confirmed sarcopenia using HGS and KES cut-off points were calculated. Pearson correlations were performed to evaluate the relationship between ASMI and limbs strength. A regression analysis was conducted to examine which variables best predict ASMI values. A multivariate analysis of covariance was performed to assess the effect of independent variables on KES and HGS.

Results

Using cutoff points for low KES identified 24 patients with probable sarcopenia and two with confirmed sarcopenia. Conversely, using the EWGSOP2 cut off points for low HGS, identified only one patient with probable sarcopenia and none of the patients with confirmed sarcopenia.

Conclusion

KES cut-off points using a simple hand-held dynamometer can assist in the identification of probable and confirmed sarcopenia using EWGSOP2 cut off points for low muscle mass in a population of older T2DM patients for further analysis and early treatment. This is notably true in patients possessing high body mass index (BMI) alongside normal ASMI and HGS, potentially reducing false positive sarcopenia screening results.

Trial registration

ClinicalTrials.gov PRS: NCT03560375. Last registration date (last update): 06/06/2018. The trial was a-priori registered before actual recruitment of subjects.

Fat-free/lean body mass in children with insulin resistance or metabolic syndrome: a systematic review and meta-analysis

BACKGROUND

Lean / Fat Free Body Mass (LBM) is metabolically involved in active processes such as resting energy expenditure, glucose uptake, and myokine secretion. Nonetheless, its association with insulin sensitivity / resistance / glucose tolerance and metabolic syndrome remains unclear in childhood.

METHODS

The current investigation aimed to examine the differences in fat-free mass /lean body mass according to the presence of insulin sensitivity/insulin resistance/glucose tolerance/metabolic syndrome in children. A systematic search was carried out in Medline/PubMed, Embase, Scopus, Web of Science, and SciELO, covering the period from each database's respective start to 21 June 2021. Two researchers evaluated 7111 studies according to the inclusion criteria: original human studies, written in English or Spanish, evaluating fat-free mass/lean body mass in children and adolescents including both with and without insulin sensitivity/insulin resistance /glucose tolerance and metabolic syndrome and reported the differences between them in terms of fat free mass/lean body mass. The results of the studies were combined with insulin sensitivity, insulin, resistance, glucose tolerance and metabolic syndrome. The standardized mean difference (SMD) in each study was calculated and combined using the random-effects model. Heterogeneity between studies was tested using the index of heterogeneity (I2), leave-one-out sensitivity analyses were performed, and publication bias was assessed using the Egger and Begg tests.

RESULTS

Finally, 15 studies which compared groups defined according to different glucose homeostasis criteria or metabolic syndrome out of 103 eligible studies were included in this systematic review and 12 studies in the meta-analysis. Meta-analysis showed lower fat-free mass/lean body mass percentage in participants with insulin resistance/glucose tolerance/metabolic syndrome (SMD -0.47; 95% CI, - 0.62 to - 0.32) while in mass units (kg), higher values were found in the same group (SMD, 1.01; 95% CI, 0.43 to 1.60).

CONCLUSIONS

Our results identified lower values of fat-free mass/lean body mass (%) in children and adolescents with insulin resistance/glucose tolerance/metabolic syndrome and higher values of fat-free mass/lean body mass when these are expressed in kg. The evidence of the impact of lean mass on children's glucose homeostasis or metabolic syndrome is limited, so future studies research should focus on explaining the effect of fat-free mass/lean body mass on different metabolic outcomes. Moreover, it may be interesting to evaluate the quality (muscle density) or functional (muscle strength) outcomes in addition to both absolute (kg) and relative (%) values in future studies. The systematic review was prospectively registered at PROSPERO (registration number CRD42019124734; available at: http://www.crd.york.ac.uk/prospero [accessed: 05 April 2019]).

Metabolic syndrome and its association with components of sarcopenia in older community-dwelling Chinese

Aging and obesity contribute to muscle dysfunction. This study aimed to determine the cross-sectional associations between components of metabolic syndrome (MetS) and sarcopenia in 251 older community-dwelling Chinese. The total fat-free mass was measured by dual-energy X-ray absorptiometry, muscle strength (handgrip strength) by a handheld dynamometer, physical performance by 4-meter walk, 5-time chair stand test, and the short physical performance battery (SPPB). MetS was defined using the International Diabetes Federation (IDF) criteria. The participants with MetS had a higher appendicular skeletal muscle mass (ASM) and relative ASM (RASM). The males with MetS had higher handgrip strength, and the females with MetS had higher SPPB scores. After adjusting for age and body mass index, the participants with an increased waist circumference had a higher ASM, and those with increased diastolic blood pressure (DBP) also had higher handgrip strength. The males with elevated fasting blood glucose (FBG) levels had a lower gait speed. Components of MetS, such as DPB and FBG, were associated with muscle strength and physical performance in older adults. These results suggest that muscle strength and function should be considered in treating older adults with MetS.

Lipoprotein subfractions in patients with sarcopenia and their relevance to skeletal muscle mass and function

OBJECTIVE

Loss of skeletal muscle mass is a characteristic of aging. Growing evidence suggests the role of fatty acids and their derived lipid intermediates in the regulation of skeletal muscle and function. However, the exact association between lipoprotein subfractions and sarcopenia in elderly individuals remains unclear. In this study, we aimed to investigate the levels of lipoprotein subfractions in sarcopenia patients and their relationship with skeletal muscle mass and function.

METHODS

A total of 84 elderly Chinese subjects aged ≥65 years who did not have diseases that obviously affected lipid metabolism were included. Concentrations of lipoprotein subfractions, including total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), HDL2, HDL3, low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), VLDL3, LDL-particle (LDL-P), lipoprotein(a) and remnant-like particle cholesterol (RLP-C), were determined by vertical auto profile. Triglyceride (TG) was measured by an enzymatic colorimetric assay. The skeletal muscle index (SMI) was assessed by bioelectrical impedance analysis. Handgrip strength was measured using a hand-held dynamometer.

RESULTS

The levels of TC, TG, LDL-C, LDL-P, IDL, VLDL, VLDL3, RLP-C and C-reactive protein were significantly higher in sarcopenia patients than in controls (p < 0.05). Pearson Product-Moment Correlation Coefficient analysis showed that the TC, TG, LDL-C, IDL, VLDL, VLDL3, and RLP-C levels were negatively associated with the SMI; The TG, IDL, VLDL, VLDL3, and RLP-C were negatively correlated with handgrip strength. In multivariate stepwise regression analysis, the VLDL and RLP-C levels were significantly correlated with the SMI. The sensitivity and specificity of the combined measurement of VLDL and RLP-C in predicting sarcopenia were 69.8% and 92.5% (AUC: 0.831; 95% CI:(0.739, 0.924); p < 0.05).

CONCLUSION

The occurrence of sarcopenia is associated with disorders of lipid metabolism, particularly VLDL and RLP-C.

Prevalence of Metabolic Syndrome According to Absolute and Relative Values of Muscle Strength in Middle-Aged and Elderly Women

Metabolic syndrome (MetS) increases with age, obesity, low physical activity, and decreased muscle strength. Although many studies have reported on grip strength and MetS, few studies have been conducted on leg strength. The purpose of this study was to analyze the prevalence of MetS according to absolute and relative leg strength values in middle-aged and older women. The participants were 1053 women who visited the healthcare center: middle-aged (n = 453) and older (n = 601). MetS was diagnosed using the criteria established by the third report of the National Cholesterol Education Program Adult Treatment Panel III and the World Health Organization's Asia Pacific guidelines for waist circumference. For leg strength, knee flexion and extension were performed using isokinetic equipment. Grip strength was measured using a grip dynamometer and classified into quartiles. Analysis of prevalence using logistic regression showed that MetS was present in 21.2% of middle-aged and 39.4% of older women. The lowest relative leg extension increased 2.5 times in the middle-aged and 1.5 times in older women (p < 0.05). However, leg flexion did not have a significant prevalence in either age group. The prevalence of MetS in middle-aged and older women with the lowest relative grip strength increased 1.5 and 1.2 times, respectively. Conversely, the lower the absolute leg extension strength, the lower the MetS prevalence was at 0.520 in middle-aged and 0.566 in older women (p < 0.05). In conclusion, the prevalence of MetS increased in women with low relative grip and leg strengths. Specifically, the lower the relative leg extension muscle strength, the higher the prevalence of MetS. In addition, the prevalence of MetS increased in the high-frequency alcohol consumption and non-physical activity group.

Cutoff points of adiposity anthropometric indices for low muscle mass screening in middle-aged and older healthy women

Background

The reduction of female sex hormones causes changes in the contractile properties of muscles as well as infiltration of fat in the muscle tissue. This results in a consequent decline in muscle strength. These changes are related to higher levels of functional impairment and physical disability. In this sense, several anthropometric indices have been used to quantify body and visceral fat. Thus, the objective of this paper is to propose cutoff points for adiposity anthropometric indices in order to identify low muscle mass, as well as to analyze the relationship between these indices and low muscle mass in middle-aged and older women.

Methods

Cross-sectional analytical study carried out in the Northeast of Brazil. The sample was formed by 593 women between 40—80 years old. Data collection included anthropometric assessment (BMI: Body Mass Index – WC: Waist Circumference – WHR: Waist-to-hip Ratio – WHtR: Waist-to-height Ratio – CI: Conicity Index – BAI: Body Adiposity Index – VAI: Visceral Adiposity Index – LAP: Lipid Accumulation Product), bioimpedance test and biochemical dosage. Moreover, sociodemographic data and practice of physical activity were collected. Descriptive statistics, Student's t-test, ROC curves, chi-squared and logistic regression were performed.

Results

The participants had a mean age of 53.11 (8.89) years, BMI of 28.49 (5.17) kg/m² and WC of 95.35 (10.39). The prevalence of low muscle mass was 19.4%. Based on sensitivity and specificity of adiposity anthropometric indices, cutoff points were developed to identify the presence of low muscle mass (p < 0.05), except for VAI. After logistic regression, WC (OR = 6.2; CI 95%: 1.4—28.1), WHR (OR = 1.8; CI: 1.0—3.4), WHtR (OR = 5.0; CI 95%: 1.0—23.7) and BAI (OR = 14.5; CI 95%: 6.6—31.7) were associated with low muscle mass.

Conclusions

All anthropometric indices, except VAI, showed adequate accuracy in identifying low muscle mass in women, especially those that took into account WC. This suggests that they can become accessible and also be cost-effective strategies for assessing and managing health outcomes related to muscle mass analysis.

Computed Tomography-Derived Myosteatosis and Metabolic Disorders

The role of ectopic adipose tissue infiltration into skeletal muscle (i.e., myosteatosis) for metabolic disorders has received considerable and increasing attention in the last 10 years. The purpose of this review was to evaluate and summarize existing studies focusing on computed tomography (CT)-derived measures of myosteatosis and metabolic disorders. There is consistent evidence that CT-derived myosteatosis contributes to dysglycemia, insulin resistance, type 2 diabetes mellitus, and inflammation, and, to some extent, dyslipidemia, independent of general obesity, visceral fat, and other relevant risk factors, suggesting that it may serve as a tool for metabolic risk prediction. Identification of which muscles should be examined, and the standardized CT protocols to be employed, are necessary to enhance the applicability of findings from epidemiologic studies of myosteatosis. Additional and longer longitudinal studies are necessary to confirm a role of myosteatosis in the development of type 2 diabetes mellitus, and examine these associations in a variety of muscles across multiple race/ethnic populations. Given the emerging role of myosteatosis in metabolic health, well-designed intervention studies are needed to investigate relevant lifestyle and pharmaceutical approaches.

Exploring the Impact of Obesity on Skeletal Muscle Function in Older Age

Sarcopenia is of important clinical relevance for loss of independence in older adults. The prevalence of obesity in combination with sarcopenia ("sarcopenic-obesity") is increasing at a rapid rate. However, whilst the development of sarcopenia is understood to be multi-factorial and harmful to health, the role of obesity from a protective and damaging perspective on skeletal muscle in aging, is poorly understood. Specifically, the presence of obesity in older age may be accompanied by a greater volume of skeletal muscle mass in weight-bearing muscles compared with lean older individuals, despite impaired physical function and resistance to anabolic stimuli. Collectively, these findings support a potential paradox in which obesity may protect skeletal muscle mass in older age. One explanation for these paradoxical findings may be that the anabolic response to weight-bearing activity could be greater in obese vs. lean older individuals due to a larger mechanical stimulus, compensating for the heightened muscle anabolic resistance. However, it is likely that there is a complex interplay between muscle, adipose, and external influences in the aging process that are ultimately harmful to health in the long-term. This narrative briefly explores some of the potential mechanisms regulating changes in skeletal muscle mass and function in aging combined with obesity and the interplay with sarcopenia, with a particular focus on muscle morphology and the regulation of muscle proteostasis. In addition, whilst highly complex, we attempt to provide an updated summary for the role of obesity from a protective and damaging perspective on muscle mass and function in older age. We conclude with a brief discussion on treatment of sarcopenia and obesity and a summary of future directions for this research field.

Association of metabolic phenotypes, grip strength and diabetes risk: The 15-year follow-up of The North West Adelaide Health Study, Australia

BACKGROUND

The association of diabetes risk in the long-term, metabolic phenotypes (MP) and muscle strength is unclear. We aimed to investigate the association between strictly defined MP, grip strength (GS) and diabetes.

MATERIAL AND METHODS

MP were defined according to BMI and presence of any individual metabolic abnormality for ≥18 years, in participants of the North West Adelaide Health Study (Australia) free of diabetes at baseline. The association of MP and dominant hand GS with incident diabetes over 15-years follow-up and the moderation effect of GS on the association between diabetes and MP were investigated by logistic regression models.

RESULTS

Of 3039 participants followed over 13.3 years (SD 2.6), 236 (7.8%) developed diabetes. Compared to the metabolically healthy (MH) normal weight phenotype, the metabolically unhealthy (MU) overweight (OR 6.15, 95%CI 2.43-15.59) and obese (OR 12.32, 95%CI 4.97-30.52) phenotypes were associated with a high risk of diabetes, but not the MU normal weight (OR 1.73, 95%CI 0.57-5.25), MH overweight (OR 1.15, 95%CI 0.31-4.31) or MH obese phenotypes (OR 0.77, 0.07-8.89). GS was inversely associated with diabetes (OR 0.97, 95% CI 0.95-0.99) and attenuated the risk associated with MU overweight (beta = -0.296, p = 0.039) and MU normal weight (beta = -0.773; p for interaction = 0.009).

CONCLUSION

Strictly defined MP (rather than based on metabolic syndrome criteria) and GS, a proxy of muscle strength, might be useful for stratifying the risk of diabetes in the long-term. Improving muscle strength might be an important strategy to reduce diabetes risk.

Respiratory Muscle Strengths and Their Association with Lean Mass and Handgrip Strengths in Older Institutionalized Individuals

The study of reduced respiratory muscle strengths in relation to the loss of muscular function associated with ageing is of great interest in the study of sarcopenia in older institutionalized individuals. The present study assesses the association between respiratory muscle parameters and skeletal mass content and strength, and analyzes associations with blood cell counts and biochemical parameters related to protein, lipid, glucose and ion profiles. A multicenter cross-sectional study was performed among patients institutionalized in nursing homes. The respiratory muscle function was evaluated by peak expiratory flow, maximal respiratory pressures and spirometry parameters, and skeletal mass function and lean mass content with handgrip strength, walking speed and bioimpedance, respectively. The prevalence of reduced respiratory muscle strength in the sample ranged from 37.9% to 80.7%. Peak expiratory flow significantly (p < 0.05) correlated to handgrip strength and gait speed, as well as maximal inspiratory pressure (p < 0.01). Maximal expiratory pressure significantly (p < 0.01) correlated to handgrip strength. No correlation was obtained with muscle mass in any of parameters related to reduced respiratory muscle strength. The most significant associations within the blood biochemical parameters were observed for some protein and lipid biomarkers e.g., glutamate-oxaloacetate transaminase (GOT), urea, triglycerides and cholesterol. Respiratory function muscle parameters, peak expiratory flow and maximal respiratory pressures were correlated with reduced strength and functional impairment but not with lean mass content. We identified for the first time a relationship between peak expiratory flow (PEF) values and GOT and urea concentrations in blood which deserves future investigations in order to manage these parameters as a possible biomarkers of reduced respiratory muscle strength.

Diagnostic differences and agreement between the original and revised European Working Group (EWGSOP) consensus definition for sarcopenia in community-dwelling older adults with type 2 diabetes mellitus

AIM

We aimed to compare diagnostic differences for identification of sarcopenia using the original operational definition developed by the European Working Group on Sarcopenia in Older People (EWGSOP1) and the most recently revised EWGSOP2 definition in community dwelling older adults with type 2 diabetes mellitus (T2DM).

METHODS

Appendicular Lean Mass (ALM) corrected for height (ALM/m²) was assessed by dual energy X-ray absorptiometry. Muscle strength was assessed using hand-grip strength (HGS) or chair stands, and the Short Physical Performance Battery (SPPB) and gait speed were used to evaluate lower extremity physical function. Cohen's kappa (κ) statistic was applied to determine the degree of agreement between the two definitions. Chi-square analysis with Bonferroni post hoc corrections were applied to determine differences in the prevalence of sarcopenic case-findings.

RESULTS

A total of n = 87 older adults (71.2 ± 8.2 years; 66.7% males; BMI: 29.5 ± 5.8 kg/m2) were included. Agreement between the two definitions was low and non-significant (κ value = 0.118; P =  0.144). Significantly more cases of sarcopenia were identified when applying the EWGSOP1 definition (EWGSOP1: n = 6 (7%); EWGSOP2: n = 2 (2%); P = 0.004). No sex specific differences were observed. Only 2 of the 6 (33.3%) cases of sarcopenia identified by EWGSOP1 were also identified as sarcopenic when applying the EWGSOP2 diagnostic criteria.

CONCLUSIONS

We showed significant discordance and limited overlap in the number of sarcopenic case-findings when applying both EWGSOP definitions. It is unknown as to whether the new diagnostic criteria are better at identifying adverse clinical outcomes in patients with T2DM. Future investigation is therefore warranted.

A counterintuitive perspective for the role of fat-free mass in metabolic health

Fat-free mass (FFM) has long been recognized to play a role in metabolic homeostasis. Over the years, it has become widely accepted by the scientific and general community alike that having a greater FFM can be protective for metabolic health. Hence, in the context of an aging population concurrently facing sarcopenia and an elevated incidence of metabolic diseases, substantial efforts are being made to study and develop interventions aiming to maintain or increase FFM. However, accumulating evidence now suggests that a large FFM may be deleterious to metabolic health, at least in some populations. The objective of this article is thus to raise awareness surrounding these results and to explore possible explanations and mechanisms underlying this counterintuitive association.

Obesity-associated poor muscle quality: prevalence and association with age, sex, and body mass index

BACKGROUND

Muscle quality (i.e., the expression of muscle function per unit of muscle mass) has been proposed as a clinically-relevant measure to detect individuals at risk of functional incapacity. Individuals with obesity might be at an increased risk of having poor muscle quality. Thus, we aimed to analyze the prevalence of poor muscle quality in obese individuals, to determine associated variables, and to provide normative values for this population.

METHODS

203 individuals with obesity (103 women, age: 18-75 years, body mass index (BMI): 35-64 kg·m^- 2) participated in this cross-sectional study. Their muscle strength (handgrip dynamometry), muscle power (sit-to-stand test) and muscle mass (bioelectrical impedance analysis) were measured, and muscle quality (strength/power to muscle mass ratio) was compared with reference values obtained in young healthy individuals. Muscle quality was individually categorized as normal, low or poor based on specific muscle strength and power (i.e., strength and power per unit of muscle mass, respectively). Sex and age-specific normative values of specific muscle strength and power were computed for the whole cohort.

RESULTS

Age and being a woman were inversely associated with specific muscle strength, with age being also inversely associated with specific muscle power. A small proportion of participants (6%) presented with an impaired (i.e., low/poor) specific muscle power while most of them (96%) had impaired specific muscle strength. Eventually, 84% of the participants were deemed to have poor muscle quality. Being a woman (odds ratio [OR]: 18.09, 95% confidence intervals [CI]: 4.07-80.38), age (OR: 1.06, 95%CI: 1.03-1.10) and BMI (OR: 1.22, 95%CI: 1.07-1.38) were independently associated with a higher risk of poor muscle quality in adjusted analyses.

CONCLUSIONS

These findings show a high prevalence of poor muscle quality among individuals with obesity, with age, sex and BMI being independent predictors.

Utilization of Hydroxyl-Methyl Butyrate, Leucine, Glutamine and Arginine Supplementation in Nutritional Management of Sarcopenia-Implications and Clinical Considerations for Type 2 Diabetes Mellitus Risk Modulation

While onset characteristics may vary, sarcopenia gradually develops over time as a result of the aging process, leading to muscle loss, disturbance of the muscle to fat ratio, and a variety of negative symptoms undermining the wellbeing, quality of life, and lifespan in the aging population globally. There is evidence that sarcopenia may be a cause and consequence of type 2 diabetes mellitus (T2DM) in the aging population. The importance of nutritional management in the prevention and/or deceleration of sarcopenia is critical, with the main focus placed on the amount and quality of protein intake. Significant efforts are being made towards the development of medical nutrition therapies involving certain amino acids and amino compounds, as well as their combinations, for the improvement in muscle strength, muscle function and protein synthesis. This may reduce hospitalization times and hasten the recovery of patients with sarcopenia. The administration of protocols with varying dose and frequencies, as well as their efficacy, is being investigated. In the work herein, we present and evaluate data derived from human trials regarding the utilization of hydroxyl-methyl butyrate (HMB), L-leucine (Leu), L-glutamine (Gln) and L-arginine (Arg) supplementation for optimal management of sarcopenia in geriatric patients, a topic of significant clinical nutrition interest which may have important implications in T2DM status.

Skeletal muscle area and density are associated with lipid and lipoprotein cholesterol levels: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Loss of muscle mass with age may be a key player in metabolic dysregulation. We examined the associations between abdominal muscle area and density with lipids and lipoproteins.

METHODS

One thousand eight hundred and sixty eight adults completed health history and physical activity questionnaires, provided venous blood samples for lipids and inflammatory biomarkers, and underwent computed tomography to quantify body composition. Associations between muscle area and density with multiple lipid measures were assessed with multivariable linear and logistic regression.

RESULTS

The mean age and body mass index of participants was 65 years and 28 kg/m², respectively, and 50% were female. After adjustment for demographics, cardiovascular disease risk factors, lipid-lowering medications, physical activity, sedentary behavior, inflammatory biomarkers, and central obesity, a 1-standard deviation increase in total abdominal, stability, and locomotor muscle areas was associated with a 13%, 11%, and 8% lower high-density lipoprotein cholesterol level, respectively (P < .05). With similar adjustment, a 1-standard deviation increase in total abdominal and stability muscle area was associated with a 13% and 12% lower total cholesterol level, respectively (P < .01). Compared to the lowest quartiles of total, stability, and locomotor muscle area, those in the higher quartiles of muscle area had over a 40% reduction in the odds of triglyceride levels greater than 150 mg/dL (P < .05). Total abdominal muscle density was positively associated with total cholesterol (P < .05) but was not associated with the other lipid outcomes.

CONCLUSION

Maintaining adequate skeletal muscle mass with age may decrease specific lipid levels related to hyperlipidemia and development of cardiometabolic disease.

Risk Factors for Sarcopenia in the Elderly with Type 2 Diabetes Mellitus and the Effect of Metformin

AIMS

Sarcopenia is a common condition in older individuals, especially in the elderly with type 2 diabetes mellitus (T2DM). The aim of the present study was to examine the risk factors for sarcopenia in elderly individuals with T2DM and the effects of metformin.

METHODS

A total of 1732 elderly with T2DM were recruited to this cross-sectional observational study, and we analyzed the data using logistic regression analyses. Skeletal muscle mass, grip strength, and usual gait speed were measured to diagnose sarcopenia according to the criteria of the Asian Working Group for Sarcopenia, combined with expert consensus on sarcopenia in China.

RESULTS

The overall prevalence of sarcopenia was 10.37% of the participants. In the multivariate analysis, sex, age, educational level, and BMI were risk factors for sarcopenia, with women more likely to develop sarcopenia relative to men (OR = 2.539, 95% CI = 1.475-4.371; P < 0.05). We observed that sarcopenia increased with age and decreased with increasing BMI and educational level (P < 0.05). Participants who took metformin alone or combined with other drugs exhibited a lower risk for sarcopenia than those who took no medication (OR = 0.510, 95% CI = 0.288-0.904 and OR = 0.398, 95% CI = 0.225-0.702, respectively; P < 0.05).

CONCLUSIONS

We showed that being female and at an older age, lower educational level, and lower BMI were risk factors for sarcopenia in elderly T2DM and that metformin acted as a protective agent against sarcopenia in these patients.

Prevalence of Metabolic Syndrome and Association with Grip Strength in Older Adults: Findings from the HOPE Study

OBJECTIVE

To determine the prevalence of metabolic syndrome (MetS) in older adults and assess the association of MetS and adverse outcomes with handgrip strength (HGS), HGS/body weight (BWT), and HGS/body mass index (BMI).

METHODS

A cross-sectional population study in Singapore. Data were collected on demographics, HGS, Timed-Up and Go (TUG), fasting glucose, lipid profile, blood pressure, waist circumference, frailty status, and cognition in 722 older adults ≥65 years old. MetS was defined using the Modified ATP III for Asians where at least three of the following conditions must be fulfilled, central obesity, high blood glucose (or diagnosed diabetes mellitus), high blood pressure (or diagnosed hypertension), low high-density lipoprotein, and high triglycerides. The waist circumference in the Modified ATP III for Asians is ≥90 cm for males or ≥80 cm for females. HGS and HGS normalized by BWT or BMI were used for the association.

RESULTS

The prevalence of MetS in older adults was 41.0%, and those ≥85 years old 50.0%. The prevalence was higher in females ≥70 years old, with 8 in 10 females ≥85 years having MetS. After adjusting for age, years of education, physical exercise, as well as history of smoking and alcohol consumption, higher HGS normalized by BWT or BMI was significantly associated with lower odds of having MetS (OR: 0.51,95% CI 0.43-0.61, p<0.01) and (OR: 0.13, 95% CI 0.07-0.24, p<0.01).

CONCLUSION

Almost 1 in 2 older adults had MetS, with the prevalence in females much higher than that in males over 70 years old. Our findings suggest that both HGS/BWT and HGS/BMI had a significant negative association with MetS, its components, and adverse effects. Further studies are needed to validate the association and to determine optimal cutoffs of HGS/BWT and HGS/BMI for MetS, and the effectiveness of interventions in averting the risk.

Metabolic syndrome (MetS) and associated factors in middle-aged women: a cross-sectional study in Northeast Brazil

We determined the prevalence of Metabolic Syndrome (MetS) and associated factors in 419 women (aged 40 to 65 years) in Northeast Brazil in a cross-sectional study conducted from April to November 2013. We defined MetS using the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. Socio-demographic variables, reproductive factors, lifestyle factors, anthropometrics, body composition, quality of life, and physical performance were assessed for their associations. We constructed multivariate Poisson regression models to estimate prevalence rate ratios (PRR) and 95% confidence intervals (CI). We identified 275 (65.6%) cases of MetS. The three most prevalent indicators were obesity (73.5%), reduced high-density lipoprotein level (63.0%), and elevated blood pressure (60.9%). In the final adjusted model, black race (PR 1.30, 95% CI: 1.07-1.57), lower grip strength/body mass index (PR 1.31, 95% CI: 1.15-1.50), and low estradiol levels (PR 1.17, 95% CI: 1.00-1.35) were associated with MetS. MetS is a long-term threat to the health of middle-aged women and a potential public health burden. These results may help in developing health promotion strategies to prevent morbidity and mortality associated with MetS in this vulnerable population.

A cross-sectional study on sarcopenia using EWGSOP1 and EWGSOP2 criteria with regional thresholds and different adjustments in a specific geriatric outpatient clinic

PURPOSE

The aim of this study was to determine the prevalence of sarcopenia according to different methods in older outpatients using regional threshold values of muscle mass and muscle strength.

METHODS

We used data from our university hospital's geriatric outpatient clinic specific to endocrinological problems, retrospectively. Sarcopenia was defined according to European Working Group on Sarcopenia in Older People (EWGSOP)1 and EWGSOP2 criteria using regional threshold values of skeletal muscle mass (SMM) with the use of different adjustments, and also according to EWGSOP2 with regional threshold values of grip strength.

RESULTS

Among 248 study participants, 53.6% were obese. There was no sarcopenic patient with the height square adjusted regional SMM thresholds for EWGSOP1 and EWGSOP2. Sarcopenia prevalence was 11.7% with EWGSOP2, and 41.1% by the use of regional grip strength thresholds for EWGSOP2 with body mass index adjustments for SMM. The comparison of EWGSOP1 versus EWGSOP2 was not possible due to lack of sarcopenic patients with height adjustment.

CONCLUSIONS

The prevalence of sarcopenia varied significantly with the application of different adjustment methods for SMM, and the use of regional grip strength thresholds in the specific patient group with normal to overweight and obese individuals. The use of regional thresholds of grip strength increased the prevalence of EWGSOP2-defined sarcopenia. The impact of the adjustment methods, the characteristics of the study population, and the regional thresholds should be taken into consideration while evaluating the results of sarcopenia studies.

Sarcopenia in Older Adults

Sarcopenia was first described in 1988 as the age-related decline of skeletal muscle mass [...].

Sarcopenia and type 2 diabetes mellitus: a bidirectional relationship

The incidence and prevalence of metabolic and musculoskeletal diseases are increasing. Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance, inflammation, advanced glycation end-product accumulation and increased oxidative stress. These characteristics can negatively affect various aspects of muscle health, including muscle mass, strength, quality and function through impairments in protein metabolism, vascular and mitochondrial dysfunction, and cell death. Sarcopenia is a term used to describe the age-related loss in skeletal muscle mass and function and has been implicated as both a cause and consequence of T2DM. Sarcopenia may contribute to the development and progression of T2DM through altered glucose disposal due to low muscle mass, and also increased localized inflammation, which can arise through inter- and intramuscular adipose tissue accumulation. Lifestyle modifications are important for improving and maintaining mobility and metabolic health in individuals with T2DM and sarcopenia. However, evidence for the most effective and feasible exercise and dietary interventions in this population is lacking. In this review, we discuss the current literature highlighting the bidirectional relationship between T2DM and sarcopenia, highlight current research gaps and treatments, and provide recommendations for future research.

Association between metabolic syndrome and limb muscle quantity and quality in older adults: a pilot ultrasound study

PURPOSE

Limited imaging studies have investigated whether limb muscle quantity and quality change after metabolic syndrome (MetS) development. This pilot study examined MetS influence on limb muscle characteristics in older adults.

METHODS

Participants were recruited from annual health examinations; their right biceps brachii, triceps brachii, rectus femoris, and gastrocnemius muscles were measured by ultrasound. Anthropometric parameters, blood biochemistry, and physical performance (handgrip strength and gait speed) were also examined.

RESULTS

Overall, 129 participants were enrolled, including 26 with MetS. Although handgrip strength was lower in MetS patients, there were no significant between-group differences considering thickness and mean echogenicity of the four muscles. Handgrip strength was positively correlated with the thickness of biceps brachii, triceps brachii, and rectus femoris but was negatively associated with their echogenicity. On multivariate analysis, triceps muscle echogenicity was trivially associated (odds ratio, 0.93; 95% confidence interval, 0.86-0.99) with MetS, possibly due to multicollinearity with grip strength.

CONCLUSION

No significant difference was recognized in limb muscle thickness and echogenicity in the geriatric population with MetS compared with healthy controls by ultrasound imaging. However, the finding might be caused by the small sample size of our participants. Future large-scale studies should explore the influence of separated risk factors of MetS on limb muscle echotexture and examine whether manifestation differs in different age populations.

Sarcopenia and type 2 diabetes mellitus: a bidirectional relationship

The incidence and prevalence of metabolic and musculoskeletal diseases are increasing. Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance, inflammation, advanced glycation end-product accumulation and increased oxidative stress. These characteristics can negatively affect various aspects of muscle health, including muscle mass, strength, quality and function through impairments in protein metabolism, vascular and mitochondrial dysfunction, and cell death. Sarcopenia is a term used to describe the age-related loss in skeletal muscle mass and function and has been implicated as both a cause and consequence of T2DM. Sarcopenia may contribute to the development and progression of T2DM through altered glucose disposal due to low muscle mass, and also increased localized inflammation, which can arise through inter- and intramuscular adipose tissue accumulation. Lifestyle modifications are important for improving and maintaining mobility and metabolic health in individuals with T2DM and sarcopenia. However, evidence for the most effective and feasible exercise and dietary interventions in this population is lacking. In this review, we discuss the current literature highlighting the bidirectional relationship between T2DM and sarcopenia, highlight current research gaps and treatments, and provide recommendations for future research.