Bed-side measures for diagnosis of low muscle mass, sarcopenia, obesity, and sarcopenic obesity in patients with chronic kidney disease under non-dialysis-dependent, dialysis dependent and kidney transplant therapy

Calf circumference predicts sarcopenia in maintenance hemodialysis

BACKGROUND

Early recognition of sarcopenia in hemodialysis (HD) patients will be of great importance in preventing adverse outcomes and improving the quality of life in these patients. The main goal of this study was to evaluate the diagnostic accuracy of calf circumference (CC) measurement in detecting sarcopenia among CKD patients undergoing maintenance HD.

METHODS

This cross-sectional study included 52 patients (53 ± 17 years) who were currently in a maintenance HD. Muscle strength was evaluated using handgrip strength, and smooth muscle mass index (SMI) was assessed through bioelectrical impedance analysis, and CC was measured at the widest part of the calf with the foot pressed against a hard surface.

RESULTS

Out of the total patient population, sarcopenia was identified in 32.7% (n = 17). The two groups were comparable in terms of age, weight, and height, but the median body mass index of sarcopenic group was statistically lower than nonsarcopenic group (21.6 kg/m2 [18.9-24.6] vs 24.7 kg/m2 [21.4-27.3]. The sarcopenic group had a substantially smaller CC than the nonsarcopenic group (30.0 cm [26.5-32.0] vs 31.5 cm [30.3-34.8], P = 0.013; respectively). In the regression analysis, CC was found to be independently associated with post-HD SMI (P < 0.001; odds ratio, 1.938; and 95% CI, 1.020-2.856). CC was positively but weakly correlated with handgrip strength, however strong and significant correlation was found between CC and SMI (r = 0.277, P = 0.047 and r = 0.733, P < 0.001; respectively). A CC of 31 cm or less predicted confirmed sarcopenia in HD patients (area under the curve = 0.709, P = 0.006, specificity = 0.556, sensitivity = 0.765).

CONCLUSIONS

Low muscle mass and potentially low muscle strength in HD patients can be accurately identified through the use of CC measurements. Specifically, a CC measurement below 31 cm has found to be a useful indicator to identify individuals on maintenance HD.

Associations of sarcopenic obesity vs either sarcopenia or obesity alone with cognitive impairment risk in patients requiring maintenance hemodialysis

BACKGROUND

The association between sarcopenic obesity (SO) and cognitive impairment (CI) risk in patients requiring maintenance hemodialysis (MHD) is not known. In this study, we investigated the prevalence of SO in MHD patients. Furthermore, we would explore and compare the associations between SO, sarcopenia, and obesity with CI risk in this population.

METHODS

A multicenter, cross-sectional study was conducted. Data from 2743 adult MHD patients were recorded. SO was defined as the co-occurrence of sarcopenia and obesity. Cognitive function was assessed with the Mini-Mental State Examination (MMSE). Multiple logistic regression models, stratified analyses, and interactive analyses were conducted.

RESULTS

21.58% of the participants met the criteria for SO. The overall prevalence of CI was 23.3% in our study. Participants in the SO group had the highest CI prevalence (34.6%). The association between SO and CI was weakened but remained statistically significant after adjusting for age, sex, and educational status (odds ratio, 1.47; 95% CI, 1.11-1.96). However, associations between sarcopenia, obesity, and CI disappeared after adjusting for these variables. The additional adjustment did not attenuate the significant association between SO and CI. Subgroup analyses and interactive analyses showed that the associations were similar across subgroups (P > 0.05 for interaction for all).

CONCLUSIONS

SO and CI are highly prevalent in MHD patients. Participants with SO are at significantly higher risk of CI than those with sarcopenia or obesity alone. Furthermore, this association is consistent across different subgroups.

Coexistence of Low Muscle Mass and Osteoporosis as a Predictor of Fragility Fractures in Long-Term Kidney Transplant Recipients

INTRODUCTION

Sarcopenia and osteoporosis are highly prevalent among kidney transplant recipients (KTRs). Although osteoporosis is known to increase fracture risk in KTRs, it is unclear whether sarcopenia or osteosarcopenia is associated with this increased risk. Thus, we aimed to investigate the association of the coexistence of low muscle mass (LMM) and osteoporosis with the risk of fracture in long-term KTRs.

METHODS

Exactly 342 stable KTRs underwent dual-energy X-ray absorptiometry and skeletal muscle mass index (SMI) measurement using bioelectrical impedance analysis.

RESULTS

LMM and osteoporosis were observed in 109 (31.9%) and 93 patients (27.2%), respectively. During a follow-up period of 5.1 years, 48 (14.0%) fractures occurred. KTRs with LMM had a higher fracture risk, but this was not significant (adjusted hazard ratio [aHR] 1.82, 95% confidence interval [CI] 0.94-3.50, p = 0.073). Similar results were obtained in KTRs with osteoporosis (aHR 1.84, 95% CI 0.96-3.47, p = 0.063). We divided the KTRs into four groups according to the presence of LMM and/or osteoporosis. The cumulative incidence rates of fractures were 13.0%, 11.1%, 10.5%, and 31.3% in the KTRs without both LMM and osteoporosis, those with LMM alone, those with osteoporosis alone, and those with both, respectively. The KTRs with both LMM and osteoporosis had a 2.92fold higher risk of fractures (95% CI 1.29-6.49; p = 0.010) than those without both LMM and osteoporosis.

CONCLUSION

Long-term KTRs with the coexistence of LMM and osteoporosis had an independently higher risk of fragility fractures than those without both LMM and osteoporosis. The combination of SMI and osteoporosis definitions can be used to identify KTRs with a high fracture risk.

Application of Bioelectrical Impedance Analysis in Nutritional Management of Patients with Chronic Kidney Disease

Body composition measurement plays an important role in the nutritional diagnosis and treatment of diseases. In the past 30 years, the detection of body composition based on bioelectrical impedance analysis (BIA) has been widely used and explored in a variety of diseases. With the development of technology, bioelectrical impedance analysis has gradually developed from single-frequency BIA (SF-BIA) to multi-frequency BIA (multi-frequency BIA, MF-BIA) and over a range of frequencies (bioimpedance spectroscopy, BIS). As the clinical significance of nutrition management in chronic kidney disease has gradually become prominent, body composition measurement by BIA has been favored by nephrologists and nutritionists. In the past 20 years, there have been many studies on the application of BIA in patients with CKD. This review describes and summarizes the latest research results of BIA in nutritional management of patients with CKD including pre-dialysis, hemodialysis, peritoneal dialysis and kidney transplantation, in order to provide reference for the application and research of BIA in nutritional management of chronic kidney disease in the future.

Association of Alpha-Actinin-3 Polymorphism With Sarcopenia in Kidney Transplant Recipients

BACKGROUND

Sarcopenia is defined as the loss of skeletal muscle mass and function and is associated with increased mortality. Certain genetic polymorphisms represent risk factors used to assess the incidence of sarcopenia; however, few studies have evaluated the association between genetic polymorphisms and sarcopenia after kidney transplantation (KTx). We examined single-nucleotide polymorphisms (SNPs) in the genes involved in sarcopenia after KTx.

METHODS

Sixty-five patients who underwent KTx were enrolled in this study. We used the psoas mass index (PMI; the cross-sectional area of the bilateral psoas muscle/height) as a surrogate marker for assessing the extent of sarcopenia. We determined the PMI before KTx and 1 year after KTx, and we identified 5 SNPs in 5 genes associated with sarcopenia in the general population. Finally, the link between the changes in PMI 1 year after KTx and each SNP was examined.

RESULTS

The median PMI before KTx and 1 year after KTx was 7.4 (4.6-13.2) and 7.0 (3.6-13.6), respectively. The PMI decreased in 43 patients (66.2%). The alpha-actinin-3 rs1815739 genotype was associated with changes in PMI; the distribution of CT+TT genotypes in the PMI decrease group was significantly higher than that of the CC genotype (odds ratio, 4.23; 95% CI 0.05-0.97; P = 0.025). Moreover, the T allele frequency was significantly higher in the PMI decrease group than in the PMI increase group (odds ratio, 2.34; 95% CI 0.18-0.950; P = 0.025).

CONCLUSION

The alpha-actinin-3 rs1815739 genotype may represent a genetic risk factor for sarcopenia after KTx.

Nutritional status and the risk of malnutrition in older adults with chronic kidney disease - implications for low protein intake and nutritional care: A critical review endorsed by ERN-ERA and ESPEN

Increased life expectancy is posing unprecedented challenges to healthcare systems worldwide. These include a sharp increase in the prevalence of chronic kidney disease (CKD) and of impaired nutritional status with malnutrition-protein-energy wasting (PEW) that portends worse clinical outcomes, including reduced survival. In older adults with CKD, a nutritional dilemma occurs when indications from geriatric nutritional guidelines to maintain the protein intake above 1.0 g/kg/day to prevent malnutrition need to be adapted to the indications from nephrology guidelines, to reduce protein intake in order to prevent or slow CKD progression and improve metabolic abnormalities. To address these issues, the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Renal Nutrition group of the European Renal Association (ERN-ERA) have prepared this conjoint critical review paper, whose objective is to summarize key concepts related to prevention and treatment of both CKD progression and impaired nutritional status using dietary approaches, and to provide guidance on how to define optimal protein and energy intake in older adults with differing severity of CKD. Overall, the authors support careful assessment to identify the most urgent clinical challenge and the consequent treatment priority. The presence of malnutrition-protein-energy wasting (PEW) suggests the need to avoid or postpone protein restriction, particularly in the presence of stable kidney function and considering the patient's preferences and quality of life. CKD progression and advanced CKD stage support prioritization of protein restriction in the presence of a good nutritional status. Individual risk-benefit assessment and appropriate nutritional monitoring should guide the decision-making process. Higher awareness of the challenges of nutritional care in older adult patients with CKD is needed to improve care and outcomes. Research is advocated to support evidence-based recommendations, which we still lack for this increasingly large patient subgroup.

Diagnosis, prevalence, and outcomes of sarcopenia in kidney transplantation recipients: A systematic review and meta-analysis

The prevalence of sarcopenia and its clinical predictors and clinical impact vary among kidney transplant recipients (KTRs), in part because of different diagnostic criteria. This study aimed to assess the reported diagnosis criteria of sarcopenia and compare them in terms of prevalence, clinical predictors, and impact of sarcopenia. The Medline, Embase, and Cochrane Library were searched for the full-length reports published until 28 January 2022. The subgroup analysis, meta-regression, and sensitivity analysis were performed and heterogeneity was assessed using the I² . A total of 681 studies were retrieved, among which only 23 studies (including 2535 subjects, 59.7% men, mean age 49.8 years) were eventually included in the final analysis. The pooled prevalence in these included studies was 26% [95% confidence interval (95% CI): 20-34%, I²  = 93.45%], including 22% (95% CI: 14-32%, I²  = 88.76%) in men and 27% (95% CI: 14-41%, I²  = 90.56%) in women (P = 0.554 between subgroups). The prevalence of sarcopenia diagnosed using low muscle mass was 34% (95% CI: 21-48%, I²  = 95.28%), and the prevalence of using low muscle mass in combination with low muscle strength and/or low physical performance was 21% (95% CI: 15-28%, I²  = 90.37%) (P = 0.08 between subgroups). In meta-regression analyses, the mean age (regression coefficient: 1.001, 95% CI: 0.991-1.011) and percentage male (regression coefficient: 0.846, 95% CI: 0.367-1.950) could not predict the effect size. Lower body mass index (odds ratio (OR): 0.57, 95% CI: 0.39-0.84, I²  = 61.5%), female sex (OR: 0.31, 95% CI: 0.16-0.61, I²  = 0.0%), and higher age (OR: 1.08, 95% CI: 1.05-1.10, I²  = 10.1%) were significantly associated with a higher risk for sarcopenia in KTRs, but phase angle (OR: 0.81, 95% CI: 0.16-4.26, I²  = 84.5%) was not associated with sarcopenia in KTRs. Sarcopenia was not associated with rejections (risk ratio (RR): 0.67, 95% CI: 0.23-1.92, I²  = 12.1%), infections (RR: 1.03, 95% CI: 0.34-3.12, I²  = 87.4%), delayed graft functions (RR: 0.81, 95% CI: 0.46-1.43, I²  = 0.0%), and death (RR: 0.95, 95% CI: 0.32-2.82, I²  = 0.0%) in KRTs. Sarcopenia was found to be very common in KRTs. However, we have not found that sarcopenia had a negative impact on clinical health after kidney transplantation. Large study cohorts and multicentre longitudinal studies in the future are urgently needed to explore the prevalence and prognosis of sarcopenia in kidney transplant patients.

The Association of Sarcopenia and Central Obesity with Mortality Risk in Patients with Chronic Kidney Disease - a 2-Year Observational Study

Background

Patients with chronic kidney disease (CKD) face numerous challenges regarding their nutritional status, including undernutrition, wasting, overweight, and obesity. However, there is a gap in the knowledge on the importance of nutritional status on the survival of CKD in patients along the spectrum of progression of CKD.

Objectives

This study aimed to investigate the association of several nutritional measures with all-cause mortality. The hypothesis was that indicators of nutritional status exceeding BMI are associated with increased mortality risk.

Methods

One-hundred seventy adult patients with predialysis CKD (n = 82), receiving hemodialysis (n = 42) or kidney transplantation (n = 46) were recruited from 2014 to 2019. At baseline, nutritional status was assessed by anthropometry, body composition, and muscle function by handgrip strength. Patient survival was assessed after a 2-y follow-up by Cox regression models adjusted for age, sex, and renal function and generalized additive models.

Results

Thirty-one patients (18%) died during the 2-y follow-up. Sarcopenia (n = 30) was associated with an increased risk of death (HR: 2.92; 95% CI: 1.24, 6.89), whereas central obesity (n = 82) was not associated with mortality (1.05; 0.51, 2.15) in the Cox regression analyses. An association between BMI and mortality risk per unit increase (0.97; 0.90, 1.05) was not observed. Other markers of nutritional status were inversely associated with mortality risk, including handgrip strength (0.89; 0.83, 0.95), mid-upper arm circumference (0.86; 0.78, 0.95), and phase angle (per 0.1 degree increase 0.86; 0.81, 0.92). In the generalized additive models, U-shaped relationships were observed between mortality risk and waist circumference and mid-upper arm muscle circumference, while BMI < 22 kg/m2 was associated with increased mortality risk.

Conclusions

Sarcopenia, but not central obesity was associated with total mortality in patients with CKD. The inclusion of muscle strength and mass measures in clinical practice should be considered.

Muscle mass, muscle strength and mortality in kidney transplant recipients: results of the TransplantLines Biobank and Cohort Study

BACKGROUND

Survival of kidney transplant recipients (KTR) is low compared with the general population. Low muscle mass and muscle strength may contribute to lower survival, but practical measures of muscle status suitable for routine care have not been evaluated for their association with long-term survival and their relation with each other in a large cohort of KTR.

METHODS

Data of outpatient KTR ≥ 1 year post-transplantation, included in the TransplantLines Biobank and Cohort Study (ClinicalTrials.gov Identifier: NCT03272841), were used. Muscle mass was determined as appendicular skeletal muscle mass indexed for height² (ASMI) through bio-electrical impedance analysis (BIA), and by 24-h urinary creatinine excretion rate indexed for height² (CERI). Muscle strength was determined by hand grip strength indexed for height² (HGSI). Secondary analyses were performed using parameters not indexed for height². Cox proportional hazards models were used to investigate the associations between muscle mass and muscle strength and all-cause mortality, both in univariable and multivariable models with adjustment for potential confounders, including age, sex, body mass index (BMI), estimated glomerular filtration rate (eGFR) and proteinuria.

RESULTS

We included 741 KTR (62% male, age 55 ± 13 years, BMI 27.3 ± 4.6 kg/m²), of which 62 (8%) died during a median [interquartile range] follow-up of 3.0 [2.3-5.7] years. Compared with patients who survived, patients who died had similar ASMI (7.0 ± 1.0 vs. 7.0 ± 1.0 kg/m²; P = 0.57), lower CERI (4.2 ± 1.1 vs. 3.5 ± 0.9 mmol/24 h/m²; P < 0.001) and lower HGSI (12.6 ± 3.3 vs. 10.4 ± 2.8 kg/m²; P < 0.001). We observed no association between ASMI and all-cause mortality (HR 0.93 per SD increase; 95% confidence interval [CI] [0.72, 1.19]; P = 0.54), whereas CERI and HGSI were significantly associated with mortality, independent of potential confounders (HR 0.57 per SD increase; 95% CI [0.44, 0.81]; P = 0.002 and HR 0.47 per SD increase; 95% CI [0.33, 0.68]; P < 0.001, respectively), and associations of CERI and HGSI with mortality remained independent of each other (HR 0.68 per SD increase; 95% CI [0.47, 0.98]; P = 0.04 and HR 0.53 per SD increase; 95% CI [0.36, 0.76]; P = 0.001, respectively). Similar associations were found for unindexed parameters.

CONCLUSIONS

Higher muscle mass assessed by creatinine excretion rate and higher muscle strength assessed by hand grip strength are complementary in their association with lower risk of all-cause mortality in KTR. Muscle mass assessed by BIA is not associated with mortality. Routine assessment using both 24-h urine samples and hand grip strength is recommended, to potentially target interdisciplinary interventions for KTR at risk for poor survival to improve muscle status.

Sarcopenia and sarcopenic obesity in chronic kidney disease: update on prevalence, outcomes, risk factors and nutrition treatment

PURPOSE OF REVIEW

This review summarizes literature from the last 18 months reporting on sarcopenia (or its components) in chronic kidney disease (CKD).

RECENT FINDINGS

The prevalence of sarcopenia in CKD is reported to be 5-62.5%, with higher rates observed later in the disease. Sarcopenic obesity rates are reported to be 2-23%. Sarcopenia in CKD is associated with increased risk of mortality, cardiovascular disease and vascular calcification. Risk factors include kidney disease itself and the impacts of CKD on lifestyle (reduced physical activity, diet changes). In earlier stages of CKD, if the risks from sarcopenia outweigh the risk of reaching end-stage renal disease, ensuring adequate energy intake combined with modest protein liberalization and physical activity may be indicated. Protein intakes above 1.3 g/kg of body weight per day should be avoided. For dialysis patients, interventions that provide a combination of carbohydrate, protein and fat appear more effective than those that provide protein alone, though it may take as long as 48 weeks for detectable changes in muscle mass.

SUMMARY

Sarcopenia is prevalent in CKD as kidney disease significantly impacts muscle mass and function. Nutrition interventions can improve components of sarcopenia, with an emphasis on adequate energy and protein.

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

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

Neutrophil-lymphocyte Ratio and C-Reactive Protein Levels are not Associated with Strength, Muscle Mass, and Functional Capacity in Kidney Transplant Patients

Chronic inflammation has been associated with components of sarcopenia; however, these associations are unknown in kidney transplant patients (KTPs). The aim of this study was to associate neutrophil-lymphocyte ratio (NLR) and C-reactive protein (CRP) with strength, muscle mass, and functional capacity in KTPs. A cross-sectional study evaluating 108 KTPs was performed. Strength was evaluated by handgrip strength and five-times-sit-to-stand test (5STS), and appendicular skeletal muscle mass (ASM) was estimated by bioelectrical impedance analysis. The ASM index (ASMI) was calculated using the ASM (kg)/height (m²). Functional capacity was assessed by the 4-m gait speed test and short physical performance battery (SPPB). The electrochemiluminescence method was used for analyzing CRP levels, and the cytometric method XN-3000 Sysmex was used for obtaining leukogram values to calculate the NLR. Linear regression analysis was used to assess the association between systemic inflammation and sarcopenia components, adjusting for confounders. NLR and CRP levels were not associated with handgrip strength (β =  - 0.231, p = 0.389; β =  - 0.291, p = 0.577), 5STS (β =  - 0.114, p = 0.288; β =  - 0.202, p = 0.334), ASM (β =  - 0.027, p = 0.813; β = 0.062, p = 0.788), ASMI (β =  - 0.036, p = 0.242; β = 0.040, p = 0.505), 4-m gait speed (β = 0.013, p = 0.082; β = 0.004, p = 0.769), and SPPB (β = 0.076, p = 0.170; β = 0.152, p = 0.157), respectively. In conclusion, NLR and CRP levels were not associated with muscle mass, strength, and functional capacity in KTPs.

The importance of muscle mass in predicting intradialytic hypotension in patients undergoing maintenance hemodialysis

Background

Patients undergoing hemodialysis are susceptible to sarcopenia. As intracellular reservoirs of water, skeletal muscles are important contributors to intradialytic hypotension. This study was designed to determine the role of skeletal muscle mass in intradialytic hypotension.

Methods

In a cross-sectional study, the body composition of 177 patients was measured immediately after hemodialysis using bioelectrical impedance analysis. The parameters measured were skeletal muscle mass, intracellular and extracellular water contents, total body water, and cell-membrane functionality (in phase angle at 50 kHz). Data from laboratory tests, chest radiography, measurements of handgrip strength and mid-arm circumference, and questionnaires were collected. The main outcome was intradialytic hypotension, defined as more than two episodes of hypotension (systolic blood pressure of <90 mmHg) with intervention over the 3 months following enrollment. Logistic regression models including each parameter related to sarcopenia were compared with a clinical model.

Results

Patients with a low ratio of skeletal muscle mass to dry body weight (SMM/WT) had a higher rate of intradialytic hypotension (41%). Most low-SMM/WT patients were female, obese, diabetic, and had a lower handgrip strength compared with the other patients. In the high-SMM/WT group, the risk of intradialytic hypotension was lower, with an odds ratio of 0.08 (95% confidence interval [CI], 0.02-0.28) and adjusted odds ratio of 0.06 (95% CI, 0.01-0.29).

Conclusion

Measurement and maintenance of skeletal muscle can help prevent intradialytic hypotension in frail patients undergoing hemodialysis.

Optimal Obesity- and Lipid-Related Indices for Predicting Metabolic Syndrome in Chronic Kidney Disease Patients with and without Type 2 Diabetes Mellitus in China

Existing obesity- and lipid-related indices are inconsistent with metabolic syndrome (MetS) in chronic kidney disease (CKD) patients. We compared seven indicators, including waist circumference (WC), body mass index (BMI), visceral fat area (VFA), subcutaneous fat area (SFA), visceral adiposity index (VAI), Chinese VAI and lipid accumulation product (LAP), to evaluate their ability to predict MetS in CKD patients with and without Type 2 diabetes mellitus (T2DM) under various criteria. Multivariate logistic regression analysis was used to investigate the independent associations between the indices and metabolic syndrome among 547 non-dialysis CKD patients, aged ≥18 years. The predictive power of these indices was assessed using receiver operating characteristic (ROC) curve analysis. After adjusting for potential confounders, the correlation between VAI and MetS was strongest based on the optimal cut-off value of 1.51 (sensitivity 86.84%, specificity 91.18%) and 2.35 (sensitivity 83.54%, specificity 86.08%), with OR values of 40.585 (8.683–189.695) and 5.076 (1.247–20.657) for males and females with CKD and T2DM. In CKD patients without T2DM, based on the optimal cut-off values of 1.806 (sensitivity 98.11%, specificity 72.73%) and 3.11 (sensitivity 84.62%, specificity 83.82%), the OR values were 7.514 (3.757–15.027) and 3.008 (1.789–5.056) for males and females, respectively. The area under ROC curve (AUC) and Youden index of VAI were the highest among the seven indexes, indicating its superiority in predicting MetS in both male and female CKD patients, especially those with T2DM.

SARC-F and SARC-CalF are associated with sarcopenia traits in hemodialysis patients

BACKGROUND

The SARC-F questionnaire assesses sarcopenia risk. The addition of a calf circumference measurement, known as SARC-CalF, has been recently proposed. We investigated possible associations of SARC-F and SARC-CalF with sarcopenia traits in patients undergoing hemodialysis.

METHODS

Thirty patients (17 men; 57 ± 15 years) were enrolled. Sarcopenia risk was assessed by SARC-F (≥4) and SARC-CalF (≥11). Probable (low muscle strength or low skeletal muscle mass [SMM]) and confirmed (both) sarcopenia were diagnosed as recommended by the revised European Working Group on Sarcopenia in Older People. Muscle strength was assessed by handgrip strength (HGS) and five-time sit-to-stand test (STS-5), and physical performance was evaluated by gait speed. SMM was assessed by bioelectrical impedance.

RESULTS

Sarcopenia risk by the SARC-F and SARC-CalF were found in 23% (n = 7) and 40% (n = 12) patients, respectively. The SARC-F and SARC-CalF were both associated with physical function, but not with SMM. Probable sarcopenia by HGS was associated with SARC-F and SARC-CalF. Moreover, both showed moderate Kappa agreement with slowness and probable sarcopenia by HGS and/or STS-5, but only SARC-CalF with probable sarcopenia by HGS. A larger sensitivity was found for SARC-CalF than SARC-F in detecting probable sarcopenia by HGS (70% vs 30%) and by HGS and/or STS-5 (63% vs 44%).

CONCLUSION

SARC-F and SARC-CalF are associated with sarcopenia traits in patients undergoing hemodialysis. SARC-CalF seems to be more strongly associated with sarcopenia traits and present a higher sensitivity for probable sarcopenia than SARC-F, as it adds a direct measurement.

Sarcopenia diagnosis using different criteria as a predictor of early mortality in patients undergoing hemodialysis

OBJECTIVES

Chronic kidney disease (CKD) is a public health problem, causing secondary sarcopenia. The aim of this study was to evaluate sarcopenia using the definitions proposed by European Working Group on Sarcopenia in Older People in 2010 (EWGSOP₂₀₁₀) and 2019 (EWGSOP₂₀₁₉) as an independent prognostic factor for worse survival in patients with CKD undergoing hemodialysis.

METHODS

Muscle mass, muscle strength, and physical performance were assessed in a cohort of patients with CKD on hemodialysis. The sample consisted of 127 patients (40% >60 y of age) and 36 patients (28.3%) died after a median follow-up length of 23.5 mo (interquartile range= 14.9 - 29). The EWGSOP₂₀₁₀ and EWGSOP₂₀₁₉ definitions were used for diagnosing sarcopenia. Sarcopenia association with mortality by both definitions was investigated using Kaplan-Meier curves and Cox proportional hazard models. The area under the curve, sensitivity, specificity, positive, and negative predictive values for both definitions were also compared.

RESULTS

Patients diagnosed with sarcopenia by both criteria had almost three times higher risk for mortality (95% confidence interval,1.45-6.06 and 1.44-6.13, respectively). Patients classified with severe sarcopenia by both definitions had a significantly lower survival, even after the adjusted analysis. The areas under the curve for EWGSOP₂₀₁₀ and EWGSOP₂₀₁₉ did not significantly differ. The sensitivity/specificity analysis was considered similar for both criteria, and around 70% of the patients was correctly classified.

CONCLUSION

Sarcopenia, notably severe sarcopenia, diagnosed by EWGSOP₂₀₁₀ or EWGSOP₂₀₁₉ criteria, is an independent prognostic factor for worse survival in this population. Early detection with effective interventions may decrease the higher mortality risk among patients with sarcopenia and CKD.

Estimation of Muscle Mass in the Integrated Assessment of Patients on Hemodialysis

Assessment of muscle mass (MM) or its proxies, lean tissue mass (LTM) or fat-free mass (FFM), is an integral part of the diagnosis of protein-energy wasting (PEW) and sarcopenia in patients on hemodialysis (HD). Both sarcopenia and PEW are related to a loss of functionality and also increased morbidity and mortality in this patient population. However, loss of MM is a part of a wider spectrum, including inflammation and fluid overload. As both sarcopenia and PEW are amendable to treatment, estimation of MM regularly is therefore of major clinical relevance. Whereas, computer-assisted tomography (CT) or dual-energy X-ray absorptiometry (DXA) is considered a reference method, it is unsuitable as a method for routine clinical monitoring. In this review, different bedside methods to estimate MM or its proxies in patients on HD will be discussed, with emphasis on biochemical methods, simplified creatinine index (SCI), bioimpedance spectroscopy (BIS), and muscle ultrasound (US). Body composition parameters of all methods are related to the outcome and appear relevant in clinical practice. The US is the only parameter by which muscle dimensions are measured. BIS and SCI are also dependent on either theoretical assumptions or the use of population-specific regression equations. Potential caveats of the methods are that SCI can be influenced by residual renal function, BIS can be influenced by fluid overload, although the latter may be circumvented by the use of a three-compartment model, and that muscle US reflects regional and not whole body MM. In conclusion, both SCI and BIS as well as muscle US are all valuable methods that can be applied for bedside nutritional assessment in patients on HD and appear suitable for routine follow-up. The choice for either method depends on local preferences. However, estimation of MM or its proxies should always be part of a multidimensional assessment of the patient followed by a personalized treatment strategy.

Correction: Bed-side measures for diagnosis of low muscle mass, sarcopenia, obesity, and sarcopenic obesity in patients with chronic kidney disease under non-dialysis-dependent, dialysis dependent and kidney transplant therapy

[This corrects the article DOI: 10.1371/journal.pone.0242671.].

Sarcopenic Obesity in Chronic Kidney Disease: Challenges in Diagnosis Using Different Diagnostic Criteria

OBJECTIVES

Obesity, muscle impairment (low muscle mass or strength), and sarcopenic obesity are present in chronic kidney disease (CKD) and are associated with worse clinical prognosis. However, the various existing definitions for these conditions make the diagnosis variable. The aim of the present study was to evaluate the agreement between diagnostic criteria for sarcopenic obesity and its components in CKD.

SUBJECT AND METHODS

267 patients with CKD were included in the study. We assessed body composition by dual-energy X-ray absorptiometry and muscle function by handgrip strength (HGS) and adiposity by body mass index (BMI), waist circumference (WC), fat mass index (FMI), and percentage of FM. Diagnosis of muscle impairment was made by HGS, appendicular lean mass (ALM), and ALM index; obesity by BMI, WC, FMI, and %FM, and sarcopenic obesity was diagnosed by concomitant presence of muscle impairment and obesity.

RESULTS

Prevalence of muscle impairment varied from 11 to 50%, higher when low muscle mass criteria were used. Prevalence of obesity varied from 26 to 62%, higher when WC and %FM criteria were used. Prevalence of sarcopenic obesity varied from 2 to 23%. Women were more affected by sarcopenic obesity. Muscle impairment and sarcopenic obesity were more prevalent among patients on hemodialysis and obesity among nondialysis-dependent and kidney transplant patients. The agreement was poor between muscle mass and strength criteria; substantial between FMI, BMI, and %FM and fair between WC and the other measures; for sarcopenic obesity, it varied from poor to almost perfect.

CONCLUSION

Significant differences were found among the various diagnostic criteria that are used in the diagnosis of sarcopenic obesity. Our results highlight the need for standardization in the diagnosis of sarcopenic obesity.