Early-stage chronic kidney disease, insulin resistance, and osteoporosis as risk factors of sarcopenia in aged population: the fourth Korea National Health and Nutrition Examination Survey (KNHANES IV), 2008-2009

Kidney function and other associated factors of sarcopenia in community-dwelling older adults: The SCOPE study

AIM

Sarcopenia is associated with several factors and medical conditions among older adults, though previous research has shown limitations and inconsistencies, especially regarding chronic kidney disease (CKD). We investigated the clinical and laboratory variables associated with sarcopenia and severe sarcopenia in older adults, focusing on kidney function measures.

METHODS

Data from community-dwelling adults aged ≥75 years participating in the SCOPE multicenter prospective cohort study were assessed cross-sectionally. Comprehensive geriatric assessment was conducted; sociodemographic and lifestyle factors, clinical variables and comorbidities, anthropometric and bioelectrical impedance analysis, blood and urine laboratory variables were collected. EWGSOP2 revised criteria were used to define sarcopenia and its severity. Estimated glomerular filtration rate (eGFR) was calculated using creatinine and non-creatinine-based equations, and CKD stages were defined accordingly.

RESULTS

1420 participants were included, prevalence of sarcopenia was 10.6 %, and 6 % had severe sarcopenia. Multivariate logistic regression analysis showed that age [OR =1.14; 95 %CI (1.09-1.19)], body mass index (BMI) [0.83 (0.79-0.88)], disability performing instrumental activities of daily living (IADL) [2.61 (1.69-4.06)], Mini Mental State Examination (MMSE) score <24 [2.75 (1.62-4.67)], osteoporosis [2.39 (1.55-3.67)], and stage 4 CKD defined by CKD-EPIBTP-B2M, a non-creatinine-based eGFR equation [2.88 (1.11-7.49)], were independently associated with sarcopenia; as were specifically with severe sarcopenia, with more pronounced associations.

CONCLUSIONS

In community-dwelling older adults, sarcopenia is a relevant condition and is associated with severe CKD, older age, IADL, cognitive impairments, osteoporosis and low BMI. These factors should be assessed for proper identification and management of older patients with sarcopenia, and even more so with severe sarcopenia.

Implications of Protein and Sarcopenia in the Prognosis, Treatment, and Management of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a common cause of chronic liver disease globally, with prevalence rapidly increasing in parallel with rising rates of obesity and metabolic syndrome. MASLD is defined by the presence of excess fat in the liver, which may induce inflammatory changes and subsequent fibrosis in high-risk patients. Though MASLD occurs frequently, there is still no approved pharmacological treatment, and the mainstay of therapy remains lifestyle modification via dietary changes, enhancement of physical activity, and management of metabolic comorbidities. Most nutrition research and clinical guidance in this disease centers on the reduction in fructose and saturated fat in the diet, although the emerging literature suggests that protein supplementation is important and implicates muscle mass and sarcopenia in disease-related outcomes. This review will assess the current data on these topics, with the goal of defining best practices and identifying research gaps in care.

Frailty-Preventing Effect of an Intervention Program Using a Novel Complete Nutritional "COMB-FP Meal": A Pilot Randomized Control Trial

Frailty is a huge concern for the aging population, and dietary nutrition is considered a key factor in the prevention of aging. To solve the problem of frailty in the aging population, we developed a novel dietary intervention program using a novel COMpletely Balanced for Frailty Prevention (COMB-FP) meal, based on the Dietary Reference Intake for Japanese; in addition, we conducted a pilot randomized control trial comparing an exercise program only (control group) with exercise plus the COMB-FP meal program (test group). We included 110 male and female healthy volunteers with pre-frailty or frailty; the trial lasted for 12 weeks. Two daily meals were replaced with the COMB-FP meals during the trial in the test group. Walking speed and cognitive function were significantly improved in the test group compared with the control group. We observed a similar pattern in other frailty-related outcomes, such as occupancy of the microbiome, World Health Organization well-being index (WHO-5), and oxidative stress. Our study might indicate the importance of a well-balanced intake of nutrients for frailty prevention.

Nutrition in the prevention and management of sarcopenia - A special focus on Asian Indians

Sarcopenia, characterized by loss of muscle mass and strength, is common in advanced old age but can be accelerated by chronic disease, malnutrition and physical inactivity. Early initiation of intervention to achieve and maintain a higher peak muscle mass and strength may allow for prevention or delay of sarcopenia and facilitate independent living even in old age. In this context, malnutrition, a significant contributor to sarcopenia, is often overlooked among the Indian population. Maintenance of an optimal energy and protein balance with adequate physical activity level is essential to preserve physical function in the aging population. However, research on the role of micronutrients in muscle maintenance, is still in its infancy. This narrative review, therefore, aims to explore the current status of International and Indian research on the role of nutrition in sarcopenia mitigation and the way forward.

Association between serum homocysteine and sarcopenia among hospitalized older Chinese adults: a cross-sectional study

OBJECTIVE

Hyperhomocysteinemia (HHcy) is considered to increase the risk of sarcopenia (S) and remains controversial. In this study, we aimed to investigate the prevalence of S among older Chinese adults and explore whether homocysteine (Hcy) was independently associated with S.

METHODS

This cross-sectional study was performed among older adults hospitalized in the Geriatric Hospital of Nanjing Medical University between June 2017 and December 2021. We measured all participants' serum Hcy levels, hand grip strength, gait speed and appendicular skeletal muscle index(ASMI) using bioelectrical impedance analysis (BIA). S was defined based on the criteria of the Asian Working Group for Sarcopenia 2 (AWGS2), which included muscle mass (ASMI< 7.0 kg/m² for men and ASMI< 5.7 kg/m² for women by BIA) and low muscle strength (handgrip strength < 28 kg for men and < 18 kg for women), and/or gait speed < 1.0 m/s. HHcy defined as Hcy ≥10 μmol/L. The strength of the association between Hcy and the risk of S was analyzed by multivariate logistic regression using three models that adjusted for possible confounding variables to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among the 441 subjects, 161 (36.5%) were diagnosed with S, and 343 (77.8%) were diagnosed with HHcy. A significant association was detected between S and serum Hcy per 1-μmol/L increase after adjustment for age, gender, education, smoking, body mass index (BMI), Mini Nutritional Assessment Short Form (MNA-SF), alanine aminotransferase (ALT), C-reactive protein (CRP), hemoglobin (Hb), albumin (ALB), diabetes, kidney disease, and statin use (OR = 1.07, 95% CI = 1.03-1.12, P = 0.002). The OR for S in the HHcy group (≥10 μmol/L) was nearly 5-fold that in the normal Hcy group (OR 4.96, 95% CI 2.67-9.24, P < 0.001). In a gender-based subgroup analysis that adjusted for age, education, smoking, BMI, MNA-SF, ALT, CRP, Hb, and ALB, female subjects with HHcy had an increased risk of S (OR 10.35, 95% CI 2.84-37.68, P < 0.001).

CONCLUSIONS

Our results demonstrated that elevated Hcy levels have an independent association with S in older adults. This suggests that the downward adjustment of HHcy (cutoff value < 10 μmol/l) might decrease the risk of S.

A pooled analysis of the association between sarcopenia and osteoporosis

BACKGROUND

Sarcopenia is a progressive generalized skeletal muscle disorder that causes the accelerated loss of muscle mass and function. Osteoporosis is a systemic condition of the skeleton that results in low bone mass and quality. Several studies have suggested that osteoporosis and sarcopenia are interrelated; however, a few studies indicate the lack of a significant association between sarcopenia and osteoporosis. We aimed to evaluate the association between sarcopenia and osteoporosis via a systematic review and pooled analysis.

METHODS

From the inception of the PubMed and Embase databases until September 2022, we conducted a systematic search for studies evaluating the relationship between sarcopenia and osteoporosis. Study appraisal and synthesis methods: We included observational studies that provided 95% confidence intervals (CIs) and risk estimates. Two reviewers independently extracted data and assessed the quality of the research. The random-effects model was applied to the pool analysis, and the odds ratios (ORs) and 95% CIs were finally calculated.

RESULTS

The primary statistic was the mutual risk between sarcopenia and osteoporosis. According to the inclusion criteria, 56 studies (796,914 participants) were finally included. Sarcopenia was significantly correlative to the risk of osteoporosis (OR, 3.06; 95% CI, 2.30-4.08), and each standard deviation increase in relative appendicular skeletal muscle mass was significantly related to a decreased risk of osteoporosis (OR, 0.65; 95% CI, 0.56-0.75). Osteoporosis observably referred to a higher risk of sarcopenia (OR, 2.63; 95% CI, 1.98-3.49).

CONCLUSION

Our research indicated that sarcopenia and osteoporosis are highly positively correlated. Osteoporosis is closely associated with the risk of sarcopenia. Our finding highlights the importance of sarcopenia screening for those at risk of osteoporosis, and vice versa. However, heterogeneity was noted among the studies, and this might have influenced the accuracy of the results. Therefore, the results of our study should be interpreted with caution.

Trends in intake and sources of dietary protein in Korean adults, 1998-2018

Although a decrease in carbohydrate intake and an increase in fat intake among Koreans have been reported, investigations of changes in protein intake have been limited. Thus, this study aimed to explore trends in the dietary intake of total, plant and animal proteins overall and by socio-demographic subgroups in Korea over the past two decades. A total of 78 716 Korean adults aged ≥ 19 years who participated in the seven survey cycles of the Korea National Health and Nutrition Examination Survey 1998-2018 were included. Dietary protein intake, overall and by source, was calculated using a single 24-h dietary recall data. Changes in dietary protein over 20 years were estimated using multiple linear regression analysis after adjusting for potential covariates. For total protein intake, a significant decrease was reported from 1998 to 2016-2018 (P for trend_linearity < 0·001), whereas an increasing trend was observed from 2007-2009 to 2016-2018 (P for trend_linearity < 0·001). In terms of protein intake by source, plant protein intake decreased while animal protein intake increased over the past two decades, indicating steeper trends during the recent decade (P for trend_linearity < 0·001). These trends were more pronounced among younger adults and those with higher household income and education levels. These findings suggest that continuous monitoring of dietary protein intake overall and by source (plant v. animal) across socio-demographic group is needed.

Creatinine-to-cystatin C ratio as a marker of sarcopenia for identifying osteoporosis in male patients with type 2 diabetes mellitus

Background

Type 2 diabetes mellitus (T2DM) is associated with the increased incidence rate of sarcopenia and osteoporosis. Serum creatinine-to-cystatin C ratio (CCR) is a novel and simple tool which can be used as an index of sarcopenia. This study aims to investigate the association between CCR and osteoporosis as well as bone mineral density (BMD) in T2DM patients.

Methods

Four hundred eighteen T2DM patients were recruited, including 166 females and 252 males. General information, BMD data and laboratory data were collected. The correlation between CCR, BMD, bone metabolism markers and osteoporosis was explored by spearman correlation, receiver-operating characteristic (ROC) curve analysis and multiple regression analysis.

Results

Spearman correlation analysis showed that there was a positive correlation between CCR and BMD as well as serum calcium in male patients (r = 0.181–0.381, P < 0.01), but such correlation was not found in the female group. In multivariate regression analysis, it was found that there was a significant correlation between CCR and BMD of total lumbar spine, hip as well as femoral neck in male patients. ROC curve showed that the optimal cut-off value of CCR for predicting osteoporosis in male patients was 6.73 with the sensitivity of 88% and specificity of 63%.

Conclusion

In male T2DM patients, CCR was negatively correlated with osteoporosis and positively correlated with BMD.

"Sarcopenia and risk of osteoporosis, falls and bone fractures in patients with chronic kidney disease: A systematic review"

Background

Chronic kidney disease [CKD] has been suggested to increase the risk of osteoporosis, sarcopenia, falls, and fractures. The aim of this systematic review was to explore the occurrence of osteoporosis, falls, and fractures in patients with sarcopenia and CKD, and to explore the possible association between sarcopenia and osteoporosis, falls, and fractures in patients with CKD.

Methods

This systematic review was conducted according to the PRISMA guideline. The protocol was registered at PROSPERO. The systematic literature search was conducted in Pubmed [1966 to present] and EMBASE [1974 to present] on December 4, 2020. We searched for articles on CKD and sarcopenia, and then we selected them with outcomes such as osteoporosis, falls, and bone fractures. The risk of bias was assessed with the Newcastle-Ottawa Scale.

Results

Five studies were eligible and included. No studies reported the occurrence of osteoporosis, falls, and bone fractures in patients with CKD and sarcopenia. Sarcopenia had a significant association with low bone mineral density [BMD] and osteoporosis in patients with CKD. The risk of bias assessed with the Newcastle-Ottawa Scale varied from 3–7 stars [median of 7]. Due to the included studies’ heterogeneity, a meta-analysis could not be conducted.

Conclusion

The occurrence of osteoporosis, falls, and bone fractures in patients with sarcopenia and CKD could not be assessed from the included studies, but an association between sarcopenia and decreased BMD/osteoporosis in patients with CKD was found. The potential mechanistic link between sarcopenia and osteoporosis in CKD needs to be investigated in future studies.

Association between serum 25-hydroxyvitamin D and physical performance measures in middle-aged and old Japanese men and women: The Unzen study

PURPOSE

Regarding epidemiological studies, the role of vitamin D in musculoskeletal functionality (muscle weakness and physical performance) among elderly people is still controversial. The purpose of the present study was to investigate the associations between 25-hydroxyvitamin D [25(OH)D] and physical performance among community-dwelling middle-aged and old Japanese men and women.

METHODS

The subjects were community-dwelling 297 men and 415 women aged 50 years and over. Data on height (m) and weight (kg) were collected. Serum 25(OH)D, parathyroid hormone, calcium, and albumin levels were measured. Serum 25(OH)D was classified into deficiency group: < 20 ng/mL, insufficiency group: 20-30 ng/mL, and sufficiency group: ≧ 30 ng/mL. Physical performance was assessed by grip strength, chair stand time, and functional reach. Information on current smoking, alcohol drinking, regular exercise, any comorbidities (hypertension, heart disease, diabetes mellitus, lung disease, and stroke), and pain (lumbar and knee) was collected.

RESULTS

Vitamin D deficiency and insufficiency based on serum 25(OH)D levels were observed in 15.2% and 56.9% of men and 52.0% and 43.6% of women, respectively. In men, higher serum 25(OH)D levels were associated with better grip strength (p for trend = 0.003), chair stand time (p for trend = 0.042), and functional reach (p for trend <0.001). On the other hand, these parameters were not associated with serum 25(OH)D levels in women.

CONCLUSION

A higher level of serum 25(OH)D was associated with better physical performance in men but not in women.

Assessment of sarcopenia as a predictor of poor overall survival for advanced non-small-cell lung cancer patients receiving salvage anti-PD-1 immunotherapy

BACKGROUND

Sarcopenia, which is defined as the loss of skeletal muscle mass, has been identified as a poor prognostic factor for cancer patients. This study sought to elucidate the effects of sarcopenia on the outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving salvage anti-programmed death-1 (PD-1) immunotherapy.

METHODS

In total, 105 NSCLC patients receiving second-line anti-PD-1 immunotherapy at the Sun Yat-sen University Cancer Center between January 2015 and December 2017 were enrolled in this study, and detailed patient data were collected. Available lumbar computed tomography images of the patients were analyzed to determine the total skeletal muscle cross-section area. The efficacy of the predictive and prognostic role of sarcopenia in progression-free survival (PFS) and overall survival (OS) was analyzed using the Kaplan-Meier method, and the risk factors were analyzed using Cox analyses.

RESULTS

We found that patients with sarcopenia receiving salvage anti-PD-1 immunotherapy had significantly worse PFS (2.67 vs. 7.96 months; P<0.001) and OS (9.08 vs. 21.84 months; P<0.001) than their non-sarcopenic counterparts. We also found that sarcopenia was associated with the neutrophil-to-lymphocyte ratio (NLR) (P=0.041), and that the NLR acts as a predictor of OS.

CONCLUSIONS

Sarcopenia was associated with a poor prognosis in advanced NSCLC patients receiving salvage anti-PD-1 immunotherapy. Further research needs to be conducted to identify more biomarkers and the patients most likely to benefit from immunotherapy.

Assessment of sarcopenia as a predictor of poor overall survival for advanced non-small-cell lung cancer patients receiving salvage anti-PD-1 immunotherapy

BACKGROUND

Sarcopenia, which is defined as the loss of skeletal muscle mass, has been identified as a poor prognostic factor for cancer patients. This study sought to elucidate the effects of sarcopenia on the outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving salvage anti-programmed death-1 (PD-1) immunotherapy.

METHODS

In total, 105 NSCLC patients receiving second-line anti-PD-1 immunotherapy at the Sun Yat-sen University Cancer Center between January 2015 and December 2017 were enrolled in this study, and detailed patient data were collected. Available lumbar computed tomography images of the patients were analyzed to determine the total skeletal muscle cross-section area. The efficacy of the predictive and prognostic role of sarcopenia in progression-free survival (PFS) and overall survival (OS) was analyzed using the Kaplan-Meier method, and the risk factors were analyzed using Cox analyses.

RESULTS

We found that patients with sarcopenia receiving salvage anti-PD-1 immunotherapy had significantly worse PFS (2.67 vs. 7.96 months; P<0.001) and OS (9.08 vs. 21.84 months; P<0.001) than their non-sarcopenic counterparts. We also found that sarcopenia was associated with the neutrophil-to-lymphocyte ratio (NLR) (P=0.041), and that the NLR acts as a predictor of OS.

CONCLUSIONS

Sarcopenia was associated with a poor prognosis in advanced NSCLC patients receiving salvage anti-PD-1 immunotherapy. Further research needs to be conducted to identify more biomarkers and the patients most likely to benefit from immunotherapy.

Associated Factors of Sarcopenia in Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis

(1) Background: To review the associated factors of sarcopenia in community-dwelling older adults. (2) Methods: PubMed, Embase, Web of Science, and four Chinese electronic databases were searched for observational studies that reported the associated factors of sarcopenia from inception to August 2021. Two researchers independently selected the literature, evaluated their quality, and extracted relevant data. The pooled odds ratio (OR) and its 95% confidence interval (CI) were calculated for each associated factors of sarcopenia using random-effects/fixed-effects models. Publication bias was assessed using funnel plot and the Eggers test. We performed statistical analysis using Stata 15.0 software. (3) Results: A total of 68 studies comprising 98,502 cases were included. Sociodemographic associated factors of sarcopenia among community-dwelling older adults included age (OR = 1.12, 95% CI: 1.10-1.13), marital status (singled, divorced, or widowed) (OR = 1.57, 95% CI: 1.08-2.28), disability for activities of daily living (ADL) (OR = 1.49, 95% CI: 1.15-1.92), and underweight (OR = 3.78, 95% CI: 2.55-5.60). Behavioral associated factors included smoking (OR = 1.20, 95% CI: 1.10-1.21), physical inactivity (OR = 1.73, 95% CI: 1.48-2.01), malnutrition/malnutrition risk (OR = 2.99, 95% CI: 2.40-3.72), long (OR = 2.30, 95% CI: 1.37-3.86) and short (OR = 3.32, 95% CI: 1.86-5.93) sleeping time, and living alone (OR = 1.55, 95% CI: 1.00-2.40). Disease-related associated factors included diabetes (OR = 1.40, 95% CI: 1.18-1.66), cognitive impairment (OR = 1.62, 95% CI: 1.05-2.51), heart diseases (OR = 1.14, 95% CI: 1.00-1.30), respiratory diseases (OR = 1.22, 95% CI: 1.09-1.36), osteopenia/osteoporosis (OR = 2.73, 95% CI: 1.63-4.57), osteoarthritis (OR = 1.33, 95% CI: 1.23-1.44), depression (OR = 1.46, 95% CI: 1.17-1.83), falls (OR = 1.28, 95% CI: 1.14-1.44), anorexia (OR = 1.50, 95% CI: 1.14-1.96), and anemia (OR = 1.39, 95% CI: 1.06-1.82). However, it remained unknown whether gender (female: OR = 1.10, 95% CI: 0.80-1.51; male: OR = 1.50, 95% CI: 0.96-2.34), overweight/obesity (OR = 0.27, 95% CI: 0.17-0.44), drinking (OR = 0.92, 95% CI: 0.84-1.01), hypertension (OR = 0.98, 95% CI: 0.84-1.14), hyperlipidemia (OR = 1.14, 95% CI: 0.89-1.47), stroke (OR = 1.70, 95% CI: 0.69-4.17), cancer (OR = 0.88, 95% CI: 0.85-0.92), pain (OR = 1.08, 95% CI: 0.98-1.20), liver disease (OR = 0.88, 95% CI: 0.85-0.91), and kidney disease (OR = 2.52, 95% CI: 0.19-33.30) were associated with sarcopenia. (4) Conclusions: There are many sociodemographic, behavioral, and disease-related associated factors of sarcopenia in community-dwelling older adults. Our view provides evidence for the early identification of high-risk individuals and the development of relevant interventions to prevent sarcopenia in community-dwelling older adults.

Effects of psoas major muscle volume in predicting the prognosis of patients with upper urinary tract urothelial carcinoma treated with radical nephroureterectomy

BACKGROUND

This study evaluated the impact of sarcopenia and psoas major muscle volume on the survival of patients with upper urinary tract urothelial carcinoma who had undergone radical nephroureterectomy.

METHODS

We reviewed data from 110 patients treated with radical nephroureterectomy in our department between June 2007 and February 2017. Psoas major muscle volume was quantified based on computed tomography data using Synapse Vincent software. The psoas major muscle volume index was calculated as psoas major muscle volume/height squared (cm3/m2). We analysed relapse-free survival, cancer-specific survival and overall survival after radical nephroureterectomy to identify factors that predicted patient survival.

RESULTS

The median psoas major muscle volume index was 121.5 cm3/m2, and the psoas major muscle volume index was <100 cm3/m2 in 34 of 110 patients (30.9%). Multivariate analysis indicated that ≥pT3-stage cancer, lymphovascular invasion and a psoas major muscle volume index of <100 cm3/m2 were independent predictors of shorter relapse-free survival, cancer-specific survival and overall survival. Using these factors, patients were stratified into three groups: low, intermediate and high risks for relapse-free survival, cancer-specific survival and overall survival.

CONCLUSIONS

Low psoas major muscle volume resulting from sarcopenia, high T stage and the presence of lymphovascular invasion was associated with poor survival in patients with urinary tract urothelial carcinoma who had undergone radical nephroureterectomy, supporting the use of psoas major muscle volume as a new objective prognostic marker.

Prevalence of Sarcopenia Among the Elderly in Korea: A Meta-Analysis

Objectives

Sarcopenia is a common disease in the elderly population that causes disability, poor quality of life, and a high risk of death. In the current study, we conducted a meta-analysis to report basic knowledge about the prevalence of sarcopenia in the elderly in Korea.

Methods

We searched for articles in the MEDLINE, Cochrane Library, Embase, and Scopus databases published until December 28, 2020. Studies investigating the prevalence of sarcopenia in elderly Koreans aged ≥65 years were included. The methodological quality of the studies was evaluated using the Newcastle-Ottawa scale. Publication bias was evaluated using the Egger test and funnel plots.

Results

In total, 3 studies and 2922 patients were included in the meta-analysis. All 3 studies used the European Working Group on Sarcopenia in Older People criteria for the diagnosis of sarcopenia. The total prevalence of sarcopenia was 13.1-14.9% in elderly men and 11.4% in elderly women.

Conclusions

This meta-analysis is the first to estimate the pooled prevalence of sarcopenia in elderly Koreans, and its findings suggest that sarcopenia is common in this population. Therefore, attention should be paid to the prevention and control of sarcopenia.

Pilot Study on Genetic Associations With Age-Related Sarcopenia

Despite strong evidence of an inheritable component of muscle phenotypes, little progress has been made in identifying the specific genetic factors involved in the development of sarcopenia. Even rarer are studies that focus on predicting the risk of sarcopenia based on a genetic risk score. In the present study, we tested the single and combined effect of seven candidate gene variants on the risk of sarcopenia. Single nucleotide polymorphisms in candidate genes were genotyped using the KASP assay. We examined 190 older adults that were classified as non-sarcopenic or sarcopenic according to the diagnostic criteria of the European Working Group on Sarcopenia in Older People. Sarcopenia was associated with Methylenetetrahydrofolate reductase, Alpha-actinin-3, and Nuclear respiratory factor 2 genotypes. The combined effect of all three polymorphisms explained 39% of the interindividual variation in sarcopenia risk. Our results suggest that the single and combined effect of Methylenetetrahydrofolate reductase, Alpha-actinin-3, and Nuclear respiratory factor 2 polymorphism is associated with sarcopenia risk in older adults. Nowadays, as the population is getting older and older, great efforts are being made to research the etiology, diagnosis and treatment of sarcopenia. At the same time, small progress has been made in understanding the genetic etiology of sarcopenia. Given the importance of research on this disease, further genetic studies are needed to better understand the genetic risk underlying sarcopenia. We believe that this small-scale study will help to demonstrate that there is still much to be discovered in this field.

The correlation between serum thyroid hormone levels and hand grip among elderly male Chinese inpatients

INTRODUCTION

Thyroid dysfunction is closely associated with skeletal muscle weakness. However, data on the optimal serum range of thyroid hormones for maintaining muscle strength in the elderly is lacking.

METHODS

We conducted a cross-sectional analysis in male elderly inpatients from the Geriatric Department of Zhongshan Hospital (affiliated to Fudan University, Shanghai, China). Serum biochemical parameters and thyroid hormones were detected for each participant. Hand grip (HG) was measured, with low hand grip defined as HG <26 kg according to the standard of the Asian Working Group for Sarcopenia. Logistic regression was used to evaluate the effects of different serum thyroid hormone levels on HG.

RESULTS

The majority of the subjects were euthyroid. The prevalence of low hand grip was 48.5%. Stratified by the free thyroxine (FT4) quartiles, the results showed HG was the highest in the third quartile. Multiple logistic regression analysis showed that compared with those in the first quartile, subjects in the third quartile of FT4 had a significantly lower risk of low hand grip (OR = 0.133, 95%CI: 0.020-0.610, p = .009), after adjusting potential confounding factors.

CONCLUSION

In elderly male inpatients, maintaining a narrower serum range of thyroid hormone might be needed to protect skeletal muscle strength.

Prevalence of sarcopenia in community-dwelling older adults using the updated EWGSOP2 definition according to kidney function and albuminuria : The Screening for CKD among Older People across Europe (SCOPE) study

Background

Loss of muscle mass and function may be more pronounced in older adults with chronic kidney disease (CKD) and with albuminuria. Thus, we investigated the prevalence of sarcopenia among community-dwelling older adults according to kidney function and grade of albuminuria. We also explored differences in the prevalence of sarcopenia according to three different equations for the estimation of glomerular filtration rate (eGFR).

Methods

A cross-sectional analysis of 1420 community-dwelling older adults (≥75 years old) included in the SCOPE study, a multicenter prospective cohort study, was conducted. Comprehensive geriatric assessment including short physical performance battery (SPPB), handgrip strength test and bioelectrical impedance analysis (BIA) was performed. Sarcopenia was defined using the updated criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2). eGFR was calculated using Berlin Initiative Study (BIS), Chronic Kidney Disease Epidemiological Collaboration (CKD-EPI) and Full Age Spectrum (FAS) equations, and urinary albumin-to-creatinine ratio (ACR) was collected to categorize CKD according to Kidney Disease Improving Global Outcomes guidelines.

Results

Median age was 79.5 years (77.0–83.0), 804 (56.6%) were women. Using EWGSOP2 definition, 150 (10.6%) participants met diagnostic criteria for sarcopenia. Moreover, 85 (6%) participants had severe sarcopenia. Sarcopenia was more prevalent in participants with more advanced stages of CKD according to BIS eq. (9.6% in stages 1 and 2 and 13.9% in stages 3a, 3b and 4, p = 0.042), and also according to CKD-EPI (9.8% vs. 14.2%, p = 0.042) and FAS although not reaching statistical signification (9.8% vs. 12.7%, p = 0.119). Thus, differences in prevalence are observed among CKD categories as estimated by different equations. Prevalence of sarcopenia was also higher with increasing albuminuria categories: 9.3% in normoalbuminuric, 13.2% in microalbuminuric and 16.8% in macroalbuminuric participants, (p = 0.019).

Conclusions

Sarcopenia is common among community-dwelling older adults, especially among those with more advanced CKD categories, with prevalence estimates differing slightly depending on the equation used for the estimation of eGFR; as well as among those with higher albuminuria categories.

Identification of sarcopenia and dynapenia in CKD predialysis patients with EGWSOP2 criteria: An observational, cross-sectional study

OBJECTIVES

Using the new European Working Group on Sarcopenia in Older People (EWGSOP2) criteria, we identified sarcopenic and dynapenic patients in a cohort of predialysis patients with chronic kidney disease (CKD), and evaluated their clinical and laboratory characteristics.

METHODS

The study population consisted of 85 (55 men) clinically stable predialysis CKD patients (92.9% in stages 3-5), with a median age of 65.0 (52.5-72.0) y. We classified as sarcopenic the patients with handgrip strength (HGS) and muscle mass both lower than the respective EWGSOP2 cutoff values and as dynapenic those in whom only HGS was less than these reference values. HGS was measured with a hand dynamometer, whereas muscle mass was measured by bioimpedance analysis. Renal function was evaluated as Modification of Diet in Renal Disease estimated glomerular filtration rate.

RESULTS

The prevalence of sarcopenia and dynapenia was, respectively, 7.1% and 17.6%. As reported in previous studies, serum albumin and hemoglobin were lower in sarcopenic patients than in patients with preserved muscle mass and strength. However, unlike in these studies, sarcopenia prevalence did not increase with CKD stage, and estimated glomerular filtration rate was similar between groups. Moreover, no difference was identified in any of the aforementioned parameters between dynapenic patients and patients with preserved muscle mass and strength.

CONCLUSIONS

The EWGSOP2 criteria identified sarcopenia in CKD with a prevalence similar to previous diagnostic criteria. In addition, they found that dynapenia was highly prevalent. Nevertheless, the EWGSOP2 criteria could be better adapted to CKD patients to improve their ability to detect high-risk sarcopenic and dynapenic patients.

Special Issue on Molecular Research Efforts in Urothelial Carcinoma: Summary of Included Topics

This Special Issue of International Journal of Molecular Sciences (IJMS) covers one of the most intriguing and emerging fields in terms of molecular oncology and uro-oncologic research efforts over the recent years, namely urothelial carcinoma of the bladder (UCB), as well as urothelial carcinoma of the upper urinary tract (UTUC). A total of 8 articles published in this Special Issue highlight the current progress in molecular oncology and cancer genetics in UCB, including a wide range of research topics, such as FGFR-inhibitors, sarcopenia in UCB, molecular predictors of response following neoadjuvant chemotherapy, exercise cardiac training impacts in the murine UCB model, Obatoclax, tropomyosins as potential biomarkers, immunotherapeutic approaches, as well as a transcriptional analysis of immunohistochemically defined UCB-subgroups. Find a brief summary of the respective articles below.

Determinants of Bone Mass and Insulin Resistance in Korean Postmenopausal Women: Muscle Area, Strength, or Composition?

PURPOSE

Muscle mass, strength, and composition determine muscle quantity and quality. However, data on muscle properties in relation to bone mass or insulin resistance are limited in Asian populations. This study aimed to investigate the relative importance of muscle measurements in regards to their relationship with lower bone mass and insulin resistance.

MATERIALS AND METHODS

In this study, 192 postmenopausal women (age, 72.39±6.07 years) were enrolled. We measured muscle cross-sectional area (CSA) and attenuation at the gluteus maximus and quadriceps muscles through quantitative computed tomography. Muscle strength and physical performance were evaluated with the hand grip test and Short Physical Performance Battery (SPPB). Pearson correlation analysis and linear regression were performed to evaluate the relationship between muscle properties and homeostatic model assessment-insulin resistance (HOMA-IR) or bone mineral density (BMD).

RESULTS

Muscle CSA, hand grip strength, and SPPB score held positive correlations with spine and hip BMDs, but not with insulin resistance. In contrast, muscle attenuation of the gluteus maximus or quadriceps was inversely related to HOMA-IR (r=-0.194, p=0.018 and r=-0.292, p<0.001, respectively), but not BMD. Compared with the control group, muscle CSA was significantly decreased in patients with osteoporosis; however, decreased muscle attenuation, indicating high fat infiltration, was found only in patients with diabetes.

CONCLUSION

Muscle mass, strength, and physical performance were associated with low bone mass, and accumulation of intramuscular fat, a histological hallmark of persistently damaged muscles, may play a major role in the development of insulin resistance in Korean postmenopausal women.

Quantitative Analysis Concerning Atrophy and Fat Infiltration of the Multifidus Muscle with Magnetic Resonance Spectroscopy in Chronic Low Back Pain

INTRODUCTION

Magnetic resonance spectroscopy (MRS) enables detailed analysis of the composition of muscular fat tissues such as intramyocellular lipids (IMCLs) and extramyocellular lipids (EMCLs). The aim of this study was to analyze the EMCL and IMCL of the multifidus muscle (Mm) using MRS in chronic low-back pain (CLBP) patients and identify their possible correlations with age, body mass index (BMI), low-back pain (LBP) visual analog scale (VAS) score, cross-sectional area (CSA), and fat infiltration of the Mm.

METHODS

Eighty patients (32 men and 48 women; mean age, 64.7 ± 1.3 years; range, 22-83 years) with VAS scores >30 mm for CLBP were included. We analyzed the gender difference and the possible correlations of age, BMI, LBP VAS, CSA, and fat infiltration of the Mm with the IMCL and EMCL of the Mm. The subjects were divided into five groups as per their age range: < 40s, 50s, 60s, 70s, and 80s. We also analyzed the EMCL and IMCL of the Mm as per the fat infiltration classification.

RESULTS

CSA was larger in the male group, EMCL was higher in the female group, and there was no significant difference in IMCL between the female and male groups. There was a significant positive correlation of EMCL with age (r = 0.33, p < 0.01) and BMI (r = 0.42, p < 0.01) and a significant negative correlation of EMCL with CSA (r = -0.61, p < 0.01). There was a significant positive correlation between IMCL and VAS (r = 0.43, p < 0.01). The EMCL and CSA of the Mm decreased with age, whereas fat infiltration increased with age.

CONCLUSIONS

These results suggest that EMCL could indicate Mm degeneration associated with aging, and IMCL could be an effective objective indicator of CLBP. The EMCL and IMCL of the Mm may be useful prognostic markers in rehabilitation strategies.

Metabolic and Molecular Basis of Sarcopenia: Implications in the Management of Urothelial Carcinoma

Sarcopenia, which represents the degenerative and systemic loss of skeletal muscle mass, is a multifactorial syndrome caused by various clinical conditions. Sarcopenia reflects not only frailty and poor general health status, but also the possible presence of advanced or progressive cancer or cancer cachexia. Therefore, sarcopenia affects the management of cancer-bearing patients, including those with urothelial carcinoma. Recently, growing evidence has shown that sarcopenia is significantly associated with higher rates of treatment-related complications and worse prognosis in patients with urothelial carcinoma, including muscle-invasive bladder cancer, upper tract urothelial carcinoma, and advanced urothelial carcinoma. Moreover, several studies reported that a post-therapeutic increase in skeletal muscle mass predicts favorable prognosis in urothelial carcinoma patients. To further explore the role of sarcopenia in the management of urothelial carcinoma patients, comprehensive understanding of its pathophysiology is vital. In this article, we reviewed the metabolic and molecular basis of cancer cachexia and sarcopenia. From this viewpoint, we discussed the possible mechanism of changes in skeletal muscle mass during the course of treatment.

Impact of Sarcopenia as a Prognostic Biomarker of Bladder Cancer

Sarcopenia, the degenerative and systemic loss of skeletal muscle mass, indicates patient frailty and impaired physical function. Sarcopenia can be caused by multiple factors, including advanced age, lack of exercise, poor nutritional status, inflammatory diseases, endocrine diseases, and malignancies. In patients with cancer cachexia, anorexia, poor nutrition and systemic inflammation make the metabolic state more catabolic, resulting in sarcopenia. Thus, sarcopenia is considered as one of manifestations of cancer cachexia. Recently, growing evidence has indicated the importance of sarcopenia in the management of patients with various cancers. Sarcopenia is associated with not only higher rates of treatment-related complications but also worse prognosis in cancer-bearing patients. In this article, we summarized metabolic backgrounds of cancer cachexia and sarcopenia and definitions of sarcopenia based on computed tomography (CT) images. We conducted a systematic literature review regarding the significance of sarcopenia as a prognostic biomarker of bladder cancer. We also reviewed recent studies focusing on the prognostic role of changes in skeletal muscle mass during the course of treatment in bladder cancer patients. Lastly, we discussed the impact of nutritional support, medication, and exercise on sarcopenia in cancer-bearing patients.

Associations between Sarcopenia and Metabolic Risk Factors: A Systematic Review and Meta-Analysis

Background

Metabolic risk factors can impact sarcopenia, but the direct relationship of metabolic risk factors with sarcopenia has not been examined. Our purpose was to investigate the effects of metabolic risk factors on sarcopenia in older adults.

Methods

Sixteen studies were found through a search of electronic databases and were subjected to a meta-analysis to investigate the differences in metabolic risk factors between patients with sarcopenia and controls. The random-effects standardized mean difference ±95% confidence interval was calculated as the effect size.

Results

The results showed that body mass index (BMI), fasting glucose, systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides (TG), homeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein cholesterol (HDL-C), and total cholesterol (d=3.252, d=2.039, d=2.956, d=2.579, d=2.123, d=1.195, d=−0.991, and d=1.007, respectively) all had relationships with sarcopenia. In addition, the effect sizes of all male groups for all variables were higher than those of the female groups. However, only the between-sex effect size of HOMA-IR (P<0.01) was significant, while those for BMI, fasting glucose, SBP, DBP, TG, HDL-C, low-density lipoprotein cholesterol, and total cholesterol were not. Finally, the metabolic risk factors appeared to be significantly related to loss of skeletal muscle.

Conclusion

Nutrition and appropriate exercise to enhance muscle strength and quality in the elderly reduce the occurrence of sarcopenia, thereby reducing the incidence of metabolic diseases.

Loop diuretics are associated with greater risk of sarcopenia in patients with non-dialysis-dependent chronic kidney disease

Introduction

Sarcopenia, the age-related loss of muscle mass and function, frequently accompanies chronic kidney disease. The aim of this study was to clarify the prevalence and the risk factors for sarcopenia among patients with non-dialysis-dependent chronic kidney disease (NDD-CKD), focusing on the use of drugs.

Methods

We conducted a cross-sectional analysis on a cohort of 260 patients with NDD-CKD in a university hospital, recruited between June 2016 and March 2017. We extracted data on patient gender, age, cause of chronic kidney disease, use of drugs, and comorbidities that could potentially affect the prevalence of sarcopenia. Sarcopenia was diagnosed using the criteria of the Asian Working Group for Sarcopenia. Logistic regression analysis was performed to analyze the association of each factor on the prevalence of sarcopenia.

Results

25.0% of our study subjects had sarcopenia. Multivariable analysis revealed that an increased risk of sarcopenia was significantly associated with age, male gender, body mass index, diabetes mellitus, and loop diuretic use (odds ratio, 4.59: 95% confidence interval, 1.81–11.61: P-value 0.001).

Conclusions

In our cohort, the prevalence of sarcopenia in patients with NDD-CKD was high, and diuretics use, particularly loop diuretic use, was suggested to be a risk factor of sarcopenia. Although loop diuretics are commonly used in patients with CKD, careful consideration of the risk of sarcopenia may be necessary.

Impact of Skeletal Muscle Mass on Long-Term Adverse Cardiovascular Outcomes in Patients With Chronic Kidney Disease

Sarcopenia, defined as skeletal muscle loss and dysfunction, is attracting considerable attention as a novel risk factor for cardiovascular events. Although the loss of skeletal muscle is common in chronic kidney disease (CKD) patients, the relation between sarcopenia and cardiovascular events in CKD patients is not well defined. Therefore, we aimed to investigate the relation between skeletal muscle mass and major adverse cardiovascular events (MACE) in CKD patients. We enrolled 266 asymptomatic CKD patients (median estimated glomerular filtration rate: 36.7 ml/min/1.73 m²). To evaluate skeletal muscle mass, we used the psoas muscle mass index (PMI) calculated from noncontrast computed tomography. The patients were divided into 2 groups according to the cut-off value of PMI for MACE. There were significant differences in age and body mass index between the low and high PMI groups (median age: 73.5 vs 69.0 years, p = 0.002; median body mass index: 22.6 vs 24.2 kg/m², p <0.001, respectively). During the follow-up period (median: 3.2 years), patients with low PMI had significantly higher risk of MACE than those with high PMI (31.7% and 11.2%, log-rank test, p <0.001). The Cox proportional hazard model showed that low PMI is an independent predictor of MACE in CKD patients (hazard ratio 3.98, 95% confidence interval 1.65 to 9.63, p = 0.0022). In conclusion, low skeletal muscle mass is an independent predictor of MACE in CKD patients. The assessment of skeletal muscle mass may be a valuable screening tool for predicting MACE in clinical practice.

High dietary sodium intake is associated with low bone mass in postmenopausal women: Korea National Health and Nutrition Examination Survey, 2008-2011

The present cross-sectional study performed using data from the Korea National Health and Nutrition Examination Survey in 9526 women older than 18 years of age demonstrates that high sodium intake is associated with lower bone mineral density and sodium intake ≥2000 mg/day is a risk factor for osteoporosis in postmenopausal women.

INTRODUCTION

Several studies have reported that large amount of dietary sodium intake is highly associated with elevated urinary calcium. However, the direct effect of excessive dietary sodium intake on bone mass, as a risk factor for osteoporosis, is still a controversial issue. The aim of the present study was to assess the relationship between high intake of sodium and lower bone mass and risk of osteoporosis in adult women.

METHODS

This cross-sectional study was performed using data from the Korea National Health and Nutrition Examination Survey (KNHANES), 2008-2011. Participants (n = 9526 women older than 18 years) were divided into a premenopausal (n = 4793) and postmenopausal (n = 4733) group. Both groups were subdivided into five groups according to quintiles of energy-adjusted sodium intake. Multiple regression analysis was performed to assess relationships between sodium intake and lower bone mass.

RESULTS

Multivariate linear regression analysis showed that high sodium intake was negatively associated with bone mineral content (BMC) and bone mineral density (BMD) in postmenopausal women. After adjusting confounding factors, high sodium intake was negatively associated with BMC and BMD of the lumbar spine in postmenopausal women. Postmenopausal women, whose sodium intake was ≥2000 mg/day (odds ratio 1.284, 95% CI 1.029-1.603, P = 0.027), were at risk of developing osteoporosis after adjustment of confounding variables.

CONCLUSIONS

The present study suggested that high sodium intake could be a potential risk factor for low bone mass after adjusting for confounding factors in postmenopausal women.

The prevalence and impact of sarcopenia on degenerative lumbar spinal stenosis

AIMS

The purpose of this study was to investigate the prevalence of sarcopenia and to examine its impact on patients with degenerative lumbar spinal stenosis (DLSS).

PATIENTS AND METHODS

This case-control study included two groups: one group consisting of patients with DLSS and a second group of control subjects without low back or neck pain and related leg pain. Five control cases were randomly selected and matched by age and gender (n = 77 cases and n = 385 controls) for each DLSS case. Appendicular muscle mass, hand-grip strength, sit-to-stand test, timed up and go (TUG) test, and clinical outcomes, including the Oswestry Disability Index (ODI) scores and the EuroQol EQ-5D were compared between the two groups.

RESULTS

The prevalence of sarcopenia, as defined by hand-grip strength, was significantly higher in the DLSS group (24%) when compared with the age- and gender-matched control group (12%) (p = 0.004). In the DLSS group, the sarcopenia subgroup demonstrated inferior results for the TUG test and ODI scores when compared with the non-sarcopenia subgroup (p = 0.006 and p = 0.039, respectively) after adjusting for age and gender.

CONCLUSION

This study demonstrated a higher prevalence of sarcopenia in patients with DLSS and highlighted its negative effect on clinical outcomes. Cite this article: Bone Joint J 2016;98-B:1093-8.

Nutrition, frailty, and sarcopenia

Frailty and sarcopenia are important concepts in the quest to prevent physical dependence, as geriatrics are shifting towards identifications of early stages of disability. Definitions of both sarcopenia and frailty are still developing, and both concepts clearly overlap in their physical aspects. Malnutrition (both undernutrition and obesity) plays a key role in the pathogenesis of frailty and sarcopenia. The quality of the diet along the lifespan has a close relation with the incidence of both entities, and nutritional interventions may be able to reduce the incidence or revert either of them. This brief review explores the role of energy and protein intake and other key nutrients on muscle function. Nutrition may be a key element of multimodal interventions for frailty and sarcopenia. The results of the "Sarcopenia and Physical fRailty IN older people: multi-componenT Treatment strategies" (SPRINTT) trial will offer key insights on the effect of such interventions in frail, sarcopenic older individuals.

Sarcopenia is associated with albuminuria independently of hypertension and diabetes: KNHANES 2008-2011

INTRODUCTION

Although sarcopenia is associated with metabolic disorders, its influence on albuminuria has not been determined. The aim of this study was to identify the relationship between sarcopenia and albuminuria in the general population.

METHODS

This was a population-based, cross-sectional study using a nationally representative sample of 2326 subjects aged ≥20years from the Korea National Health and Nutrition Examination Surveys of 2008-2011. Appendicular skeletal muscle (ASM) measured by dual-energy X-ray absorptiometry was used to assess sarcopenia, which was defined as ASM divided by body mass index, as recommended by the international consensus meeting of the National Institutes of Health. Albuminuria was defined as an albumin-to-creatinine ratio of ≥30mg/g using random spot urine samples.

RESULTS

A total of 385 (16.5%) subjects were classified as having albuminuria. Sarcopenic subjects showed a higher proportion of albuminuria than subjects without sarcopenia (odds ratios [ORs]=2.17-3.26, all P<0.05) after stratification based on the presence of hypertension, diabetes, or metabolic syndrome and a higher homeostasis model assessment of insulin resistance (all P<0.001). The albuminuria risk was comparable between insulin-sensitive subjects with sarcopenia and insulin-resistant subjects with preserved muscle mass. A multiple logistic regression analysis also demonstrated that sarcopenia was independently associated with albuminuria (OR=1.61, 95% confidence interval [CI]=1.04-2.48, P<0.05). The association between sarcopenia and albuminuria remained strong in the elderly population (ORs=1.80-2.68, P<0.05), whereas it lost its significance in the younger age group. Furthermore, the risk of albuminuria was much higher in sarcopenic obese subjects than in other groups (OR=4.90, 95% CI=3.23-7.43, P<0.001).

CONCLUSIONS

Sarcopenia was associated with an increased risk of albuminuria independent of hypertension, diabetes, and metabolic syndrome. Sarcopenia and obesity had a synergistic impact on the increased risk of albuminuria. This suggests that sarcopenic obesity as well as sarcopenia alone may be considered as novel risk factors for albuminuria.

Frailty and sarcopenia as the basis for the phenotypic manifestation of chronic diseases in older adults

Frailty is a functional status that precedes disability and is characterized by decreased functional reserve and increased vulnerability. In addition to disability, the frailty phenotype predicts falls, institutionalization, hospitalization and mortality. Frailty is the consequence of the interaction between the aging process and some chronic diseases and conditions that compromise functional systems and finally produce sarcopenia. Many of the clinical manifestations of frailty are explained by sarcopenia which is closely related to poor physical performance. Reduced regenerative capacity, malperfusion, oxidative stress, mitochondrial dysfunction and inflammation compose the sarcopenic skeletal muscle alterations associated to the frailty phenotype. Inflammation appears as a common determinant for chronic diseases, sarcopenia and frailty. The strategies to prevent the frailty phenotype include an adequate amount of physical activity and exercise as well as pharmacological interventions such as myostatin inhibitors and specific androgen receptor modulators. Cell response to stress pathways such as Nrf2, sirtuins and klotho could be considered as future therapeutic interventions for the management of frailty phenotype and aging-related chronic diseases.

Lower Serum Creatinine Is Associated with Low Bone Mineral Density in Subjects without Overt Nephropathy

Background

Low skeletal muscle mass is associated with deterioration of bone mineral density. Because serum creatinine can serve as a marker of muscle mass, we evaluated the relationship between serum creatinine and bone mineral density in an older population with normal renal function.

Methods

Data from a total of 8,648 participants (4,573 men and 4,075 postmenopausal women) aged 45–95 years with an estimated glomerular filtration rate >60 ml/min/1.73 m2 were analyzed from the Fourth Korea National Health and Nutrition Examination Survey (2008–2010). Bone mineral density (BMD) and appendicular muscle mass (ASM) were measured using dual-energy X-ray absorptiometry. Receiver operating characteristic curve analysis revealed that the cut points of serum creatinine for sarcopenia were below 0.88 mg/dl in men and 0.75 mg/dl in women. Subjects were divided into two groups: low creatinine and upper normal creatinine according to the cut point value of serum creatinine for sarcopenia.

Results

In partial correlation analysis adjusted for age, serum creatinine was positively associated with both BMD and ASM. Subjects with low serum creatinine were at a higher risk for low BMD (T-score ≤ –1.0) at the femur neck, total hip and lumbar spine in men, and at the total hip and lumbar spine in women after adjustment for confounding factors. Each standard deviation increase in serum creatinine was significantly associated with reduction in the likelihood of low BMD at the total hip and lumbar spine in both sexes (men: odds ratio (OR) = 0.84 [95% CI = 0.74−0.96] at the total hip, OR = 0.8 [95% CI = 0.68−0.96] at the lumbar spine; women: OR = 0.83 [95% CI = 0.73–0.95] at the total hip, OR=0.81 [95% CI = 0.67–0.99] at the lumbar spine).

Conclusions

Serum creatinine reflected muscle mass, and low serum creatinine was independently associated with low bone mineral density in subjects with normal kidney function.

Relationship between Stage of Chronic Kidney Disease and Sarcopenia in Korean Aged 40 Years and Older Using the Korea National Health and Nutrition Examination Surveys (KNHANES IV-2, 3, and V-1, 2), 2008-2011

Background

Protein-energy wasting is common in patients with end-stage kidney disease. However, few studies have examined the relationship between early stages of chronic kidney disease (CKD) and sarcopenia.

Methods

We conducted a cross-sectional study based on data in the Korea National Health and Nutrition Examination Survey, 2008–2011. In total, 11,625 subjects aged 40 years or older who underwent dual-energy X-ray absorptiometry were analyzed. Sarcopenia was defined based on values of appendicular skeletal muscle mass as a percentage of body weight (ASM/Wt) two standard deviations below the gender-specific mean for young adults. Estimated glomerular filtration rates (eGFR) were calculated using the CKD-EPI equation.

Results

Mean age, body mass index (BMI), and HOMA-IR were higher and caloric intake, physical activity, and vitamin D level were lower in the sarcopenia groups in both men and women. As the stage of CKD increased, the prevalence of sarcopenia increased, even in the early stages of CKD (normal and CKD1, 2, and 3-5: 2.6%, 5.6%, and 18.1% in men and 5.3%, 7.1%, and 12.6% in women, respectively; p < 0.001). In addition, a correlation analysis showed that GFR and ASM/Wt had significant correlations in both men and women. Logistic regression analyses, after adjusting for age, BMI, caloric intake, log(physical activity), vitamin D level, and log(HOMA-IR), showed that the odds ratio for sarcopenia with respect to CKD 3–5 was 1.93 (95% CI = 1.02–3.68) in men but was not statistically significant in women.

Conclusions

The prevalence of sarcopenia was higher in elderly Korean patients with even mildly reduced kidney function. Stage of CKD was associated with an increased prevalence of sarcopenia in men but not women. Thus, we should evaluate the risk of sarcopenia and work to prevent it, even in patients with early CKD.

Sarcopenia: burden and challenges for public health

Sarcopenia, operationally defined as the loss of muscle mass and muscle function, is a major health condition associated with ageing, and contributes to many components of public health at both the patient and the societal levels. Currently, no consensual definition of sarcopenia exists and therefore it is still a challenge to establish the actual prevalence of sarcopenia or to establish the direct and indirect impacts of sarcopenia on public health. Anyway, this geriatric syndrome represents a huge potential public health issue because of its multiple clinical and societal consequences. Moreover, all these aspects have an impact on healthcare costs both for the patient and the society. Therefore, the implementation of effective and broadly applicable preventive and therapeutic interventions has become a medical and societal challenge for the growing number of older persons affected by sarcopenia and its disabling complications.

Age-related impairment of pancreatic Beta-cell function: pathophysiological and cellular mechanisms

The incidence of type 2 diabetes significantly increases with age. The relevance of this association is dramatically magnified by the concomitant global aging of the population, but the underlying mechanisms remain to be fully elucidated. Here, some recent advances in this field are reviewed at the level of both the pathophysiology of glucose homeostasis and the cellular senescence of pancreatic islets. Overall, recent results highlight the crucial role of beta-cell dysfunction in the age-related impairment of pancreatic endocrine function and delineate the possibility of new original therapeutic interventions.