Sarcopenia in chronic kidney disease: what have we learned so far?

Effectiveness of rehabilitation in hospitalized hemodialysis patients as compared with rehabilitation in hospitalized patients not on hemodialysis: a retrospective cohort study

BACKGROUND

The effectiveness of rehabilitation aimed at improving the activities of daily living and physical functions may differ between hospitalized patients undergoing hemodialysis (HD) and not undergoing HD (non-HD). The aim of the present study was to compare the outcomes of rehabilitation between hospitalized HD and non-HD patients.

METHODS

This was a retrospective cohort study of inpatients who underwent rehabilitation. We measured the rehabilitation time (min/day), length of hospital stay (days), and the Barthel index (BI). In addition, at the time of admission and discharge, grip strength, isometric knee extension strength, 10 m walking speed, timed up and go test, and short physical performance battery were examined. The outcomes were then compared between the HD and non-HD groups.

RESULTS

This study was made up of 902 patients (non-HD group: 765, HD group: 137). Our analysis revealed a lower rehabilitation time [43.3 (0.6) vs. 38.8 (1.2) min/day] and longer hospital stay [48.5 (0.5) vs. 58.1 (2.3) days] in the HD group as compared with the non-HD group (p < 0.05). In addition, the 10 m walking speed [0.75 (0.02) vs. 0.66 (0.03) m/s], timed up and go test [20.8 (0.7) vs. 24.3 (1.0) sec], and short physical performance battery [6.3 (0.6) vs. 4.7 (0.6) points] at discharge were also significantly lower in the HD group as compared with the non-HD group (p < 0.05).

CONCLUSION

Rehabilitation efforts for HD patients need to be improved by securing more time for inpatient rehabilitation and promoting mobility function improvement for these patients.

Clinical and novel insights into risk factors for sarcopenia in dialysis patients: a systematic review and meta-analysis

OBJECTIVE

We employed a meta-analysis to investigate the risk factors associated with sarcopenia in patients undergoing dialysis.

METHODS

We conducted a search in PubMed, Embase, Cochrane Library, and Web of Science databases. Inclusion criteria included case-control and cohort studies on risk factors for sarcopenia in dialysis patients. The search period spanned from the inception of each database to September 20, 2024. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). Data analysis was performed using Stata 15.0.

RESULT

A total of 625 articles were screened, with 610 articles excluded based on predefined eligibility criteria, resulting in 15 articles involving 2904 individuals were included in the final analysis, meta-analysis results indicate that older dialysis patients [SMD = 0.76, 95% CI (0.54, 0.99), I2 = 81%, P = 0.001], those with a lower BMI [SMD = -0.50, 95% CI (-0.80, -0.20), I2% = 87.4%, P = 0.02], a lower SMI [SMD = -2.67, 95% CI (-3.87, -1.47), I2% = 98.2%, P = 0.001], and those with diabetes [OR = 1.43, 95% CI (1.13, 1.82), I2% = 48.8%, P = 0.03] are more likely to develop sarcopenia.

CONCLUSION

Based on current research, our study found that elderly dialysis patients, those with a lower BMI, lower SMI, and diabetic patients are more likely to develop sarcopenia. These findings highlight the necessity of early intervention for these high-risk groups. However, the study has limitations. Future research should address these limitations and investigate the mechanisms linking these risk factors to sarcopenia to develop targeted prevention and treatment strategies.

Energy Expenditure in Chronic Kidney Disease: Affecting Factors and Evaluation Methods

Chronic kidney disease (CKD) is a chronic health problem whose prevalence is increasing. Nutrition and nutrition-related factors, one of the modifiable risk factors for CKD, are of primary importance. The key to planning optimal nutritional therapy is accurately determining energy requirements and total energy expenditure. Many health problems can accompany CKD, such as protein-energy malnutrition, sarcopenia, etc, and increase the mortality rate. This study aims to present the specific factors affecting energy expenditure specific to CKD in line with the current literature, to discuss the methods used to determine energy expenditure, and to examine these methods according to groups receiving and not receiving renal replacement therapy (hemodialysis, peritoneal dialysis, and renal transplantation).

Neutrophil-to-lymphocyte ratio as a novel predictor of sarcopenia in maintenance hemodialysis patients: a cross-sectional study exploring associations across body composition categories

BACKGROUND

Sarcopenia is prevalent among hemodialysis patients and is associated with poor outcomes. The neutrophil-to-lymphocyte ratio (NLR), an easily obtainable marker of inflammation, may predict sarcopenia risk. This study aimed to investigate the association between NLR and sarcopenia risk in maintenance hemodialysis patients, examining this association in the context of obesity.

METHODS

This cross-sectional study included 411 maintenance hemodialysis patients. Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria-2019 (AWGS 2019). Body composition was assessed using bioelectrical impedance analysis. Logistic regression models examined associations between NLR and sarcopenia risk, adjusting for potential confounders. Analyses were stratified by obesity status.

RESULTS

The prevalence of sarcopenia was 51% (95% CI: 45.1-54.9%), with 37.2% classified as sarcopenic non-obese and 13.6% as sarcopenic obese. In fully adjusted models, each unit increase in NLR was associated with 10% higher odds of sarcopenia overall (OR 1.10, 95% CI: 1.00-1.21, p = 0.048). This association remained significant in sarcopenic obese patients (OR 1.15, 95% CI: 1.00-1.32, p = 0.049). Patients in the highest NLR tertile had 1.95 times higher odds of sarcopenia compared to the lowest tertile (95% CI: 1.12-3.40, p = 0.018), with a significant trend across tertiles (p-trend = 0.015).

CONCLUSIONS

NLR is independently associated with sarcopenia risk in hemodialysis patients, including those with obesity. These findings suggest NLR could serve as a simple, cost-effective tool for identifying hemodialysis patients at high risk of sarcopenia, potentially facilitating early intervention strategies.

Prediction models for sarcopenia risk in dialysis patients: a systematic review and critical appraisal

BACKGROUND

Many studies have developed or validated predictive models to estimate the risk of sarcopenia in dialysis patients, but the quality of model development and the applicability of the models remain unclear.

OBJECTIVE

To systematically review and critically evaluate currently available predictive models for sarcopenia in dialysis patients.

METHODS

We systematically searched five databases until March 2024. Observational studies that developed or validated predictive models or scoring systems for sarcopenia in dialysis patients were considered eligible. We included studies of adults (≥ 18 years of age) on dialysis and excluded studies that did not validate the predictive model. Data extraction was performed independently by two authors using a standardized data extraction table based on a checklist of key assessments and data extraction for systematic evaluation of predictive modeling research. The quality of the model was assessed using the Predictive Model Risk of Bias Assessment Tool.

RESULTS

Of the 104,454 studies screened, 13 studies described 13 predictive models. The incidence of sarcopenia in dialysis patients ranged from 6.6 to 34.4%. The most commonly used predictors were age and body mass index. In the derivation set, the reported area under the curve or C-statistic is between 0.81 and 0.95. The area under the curve reported by the external validation set is between 0.78 and 0.93. All studies had a high risk of bias, mainly due to poor reporting in the outcome and the analysis domains, and three studies had a high risk of bias in terms of applicability.

CONCLUSION

Future research should focus on validating and improving existing predictive models or developing new models using rigorous methods.

Ameliorating role of co-administration of granulocyte colony stimulating factor and sodium bicarbonate on the skeletal muscle of a rat model of chronic kidney disease (A histological and immunohistochemical study)

Over half million individuals suffer from chronic kidney disease (CKD) worldwide. In addition to raising the possibility of cardiovascular diseases, skeletal myopathy remains a challenging complication that is highly correlated with mortality and a lower quality of life. Granulocyte-colony stimulating factor (G-CSF) is an active cytokine for mobilization of immunological and hematopoietic stem cells that can replace exogenous stem cell infusions. So, it is seen as a less expensive and noninvasive tool for regenerative medicine. Sixty three rats were divided into 4 groups: I control, II CKD induced, IIIa, IIIb treated and IV recovery groups. After induction of CKD in all rats, group II were sacrificed after 4 weeks. Rats of group IIIa received NaHCO3. Group IIIb rats were injected subcutaneously by G-CSF as 100 µg/kg/day for 5 successive days in addition to NaHCO3 as group IIIa. Group IV rats were housed for 4 weeks without treatment. Serum urea, creatinine, tissue MDA& TNF-α were assessed. Renal and gastrocnemius muscle sections were evaluated for histological structure, CD34 and myogenin immune expression, morphometric and statistical analyses. The CKD group revealed a significant increase in MDA and TNF-α. Furthermore, features of renal injury, muscle degenerative changes, increased collagen and decreased CD34 and myogenin expression were observed. Alterations were partially attenuated by NaHCO3, while GCSF remarkably improved most parameters. The current results indicated that co-administration of GCSF and NaHCO3 could ameliorate CKD myopathy via attenuating oxidative stress, immunomodulation, pro-angiogenic ability, myocyte regeneration. In addition to the reduction of mitochondrial stress and maintenance of cellular homeostasis.

Risk Prediction Models for Sarcopenia in Dialysis Patients: A Systematic Review

Nowadays, numerous studies have developed risk prediction models for sarcopenia in dialysis patients. However, the quality and performance of these models have not been integrated. The purpose of our study is to provide a comprehensive overview of the current risk prediction models for sarcopenia in dialysis patients and to offer a reference for the development of high-quality prediction models. Ten electronic databases were searched from inception to March 8, 2024. Two researchers independently assessed the risk of bias and applicability of the studies, and used Revman, 5.4, software to conduct a meta-analysis of common predictors in the models. A total of 12 studies described 13 risk prediction models for dialysis patients with sarcopenia. In dialysis patients, the prevalence of sarcopenia ranged from 6.60% to 63.73%. The area under curve (AUC) of the 13 models ranged from 0.776 to 0.945. Only six models (AUC ranging from 0.73 to 0.832) were internally validated, while two were externally evaluated (AUC ranging from 0.913 to 0.955). Most studies had a high risk of bias. The most common effective predictors in the models were age, body mass index, muscle circumference, and C-reactive protein. Our study suggests that developing a prediction model for the onset of sarcopenia in dialysis patients requires a rigorous design scheme, and future verification methods will necessitate multicenter external validation.

Fat-Free Mass Derived From Bioimpedance Spectroscopy and Computed Tomography are in Good Agreement in Patients With Chronic Kidney Disease

OBJECTIVE

Malnutrition is highly prevalent in patients with kidney failure. Since body weight does not reflect body composition, other methods are needed to determine muscle mass, often estimated by fat-free mass (FFM). Bioimpedance spectroscopy (BIS) is frequently used for monitoring body composition in patients with kidney failure. Unfortunately, BIS-derived lean tissue mass (LTMBIS) is not suitable for comparison with FFM cutoff values for the diagnosis of malnutrition, or for calculating dietary protein requirements. Hypothetically, FFM could be derived from BIS (FFMBIS). This study aims to compare FFMBIS and LTMBIS with computed tomography (CT) derived FFM (FFMCT). Secondarily, we aimed to explore the impact of different methods on calculated protein requirements.

METHODS

CT scans of 60 patients with kidney failure stages 4-5 were analyzed at the L3 level for muscle cross-sectional area, which was converted to FFMCT. Spearman rank correlation coefficient and 95% limits of agreement were calculated to compare FFMBIS and LTMBIS with FFMCT. Protein requirements were determined based on FFMCT, FFMBIS, and adjusted body weight. Deviations over 10% were considered clinically relevant.

RESULTS

FFMCT correlated most strongly with FFMBIS (r = 0.78, P < .001), in males (r = 0.72, P < .001) and in females (r = 0.60, P < .001). A mean difference of -0.54 kg was found between FFMBIS and FFMCT (limits of agreement: -14.88 to 13.7 kg, P = .544). Between LTMBIS and FFMCT a mean difference of -12.2 kg was apparent (limits of agreement: -28.7 to 4.2 kg, P < .001). Using FFMCT as a reference, FFMBIS best predicted protein requirements. The mean difference between protein requirements according to FFMBIS and FFMCT was -0.7 ± 9.9 g in males and -0.9 ± 10.9 g in females.

CONCLUSION

FFMBIS correlates well with FFMCT at a group level, but shows large variation within individuals. As expected, large clinically relevant differences were observed in calculated protein requirements.

Assessment of Nutritional Intake in Patients With Kidney Failure Treated by Haemodialysis on Dialysis and Non-dialysis Days

INTRODUCTION/AIMS/OBJECTIVE

Inadequate nutritional intake in haemodialysis (HD) patients increases the risk of muscle wasting, nutrient deficiencies, leading to an increased risk of additional morbidity and mortality. We aimed to assess nutritional intake on the dialysis day and nondialysis day (NDD) of patients established on HD.

METHODS

We employed a 2-day dietary record, one on the day of dialysis and one on the NDD, and then determined nutritional intake using the Nutritics software. Muscle strength was assessed by hand grip strength, and the body composition was determined using multifrequency bioelectrical impedance recorded postdialysis.

RESULTS

We recruited 51 established HD patients dialysing between May 2022 and July 2022, of mean age 60 ± 15 years, 52.9% male, and 51% diabetic. Only 25% achieved the calorie and protein intake recommended by Kidney Disease Outcomes Quality Initiative. Most patients had inadequate consumption of fiber (96%), calcium (86%), iron (80%), zinc (82%), selenium (92%), folate (82%), vitamin A (88%), and (100%) vitamin D. On the other hand, the great majority followed the restriction guidelines for potassium (96%), phosphorus (86%), and sodium (84%), respectively. However, consumption was greater for potassium (P = .007), phosphorus (P = .015), and zinc (P = .032) on NDDs versus dialysis days, but there was no difference in protein or calorie intake between days.

CONCLUSION

Our results suggest that many of our HD patients do not achieve the recommended nutritional targets. Patient compliance with restricting sodium, potassium, and phosphate limits protein and calorie intake. HD patients are at increased risk of sarcopenia, so failure to achieve dietary protein intake will further increase this risk.

Renal function assessment in older people: comparative analysis of estimation equation with serum creatinine

Introduction

Age-related changes occurring in the kidney can lead to a reduction in Glomerular Filtration Rate (GFR); especially in older adults with multimorbidity and/or frailty, an accurate evaluation of kidney function is critical. For the estimation of GFR in patients over 70 years, CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) is often used. However, validated equations exist for old-age populations like BIS1 (Berlin Initiative Study 1) and FAS (Full Age Spectrum). Here we aimed to compare the performance of CKD-EPI, MDRD (Modification of Diet in Renal Disease), BIS1, and FAS in assessing eGFR in a population of patients over 70, to evaluate which equations show the most accurate performance in our setting.

Materials and methods

A total of 499 older adults were consecutively recruited in the Orthogeriatric ward and Oncogeriatrics clinic of IRCCS Polyclinic San Martino in Genoa Italy. eGFR was calculated using CKD-EPI, MDRD, BIS1, and FAS, calculating mean, median, standard deviation, and interquartile range. Bland-Altman graphs were used to evaluate how each equation performs with respect to the others and the concordance of the attribution of the KDIGO CKD stage was performed with Cohen's K constant and chi-squared test.

Results

Patients' mean age was 82.6 years (± 7.44), and the mean creatinine value was 0.97 (± 0.71) mg/dl. The mean value of eGFR was 70 mL/min with CKD-EPI (± 20.6) and MDRD (± 25.7), 57 mL/min with BIS1 (± 16.7) and FAS (± 19.0), respectively. BIS1 and FAS estimated lower eGFR values than CKD-EPI and MDRD. As age increases, a steady decrease in filtrate value is observed with BIS1 and FAS. MDRD and CDK-EPI do not show the same trend. The performance of the equations at a fixed eGFR value of 30 mL/min is more linear for BIS1 and FAS compared with CKD-EPI and MDRD. Upon evaluation with chi-square, the attribution of KDIGO stage was statistically different among the various equations.

Discussion

An appropriate assessment of renal function is of key clinical relevance to prevent adverse outcomes and risk of drug accumulation in older adults. Our study originally showed that in persons aged more than 70 years old BIS1 is the most accurate formula in calculating eGFR values when only serum creatinine is available.

Male Sex and Ageing are Independent Risk Factors for Sarcopenia Stage in Patients With Chronic Kidney Disease Not Yet on Dialysis

BACKGROUND

The risk of sarcopenia in older adults with chronic kidney disease (CKD) not yet on dialysis is controversial. The aims of this study were to investigate the association among sarcopenia, diabetes and predialysis CKD and evaluate the impact of gender and ageing on the risk of sarcopenia statuses in older patients with predialysis CKD.

METHODS

The participants aged ≥60 years old were recruited from the community of New Taipei City, Taiwan. Handgrip strength, appendicular skeletal muscle mass and the 6-m walk were measured. The diagnosis of sarcopenia was established based on the consensus of Asian Sarcopenia Working Group 2019. These older adults were categorised into G1, G2 and G3-5 according to the guidelines of Kidney Disease Improving Global Outcomes (KDIGO) after calculating the estimated glomerular filtration rate by the Modification of Diet in Renal Disease equation. The Chi-square test and ANOVA were used to estimate the difference of categorical and continuous variables, respectively. Polytomous logistic regression was employed to assess the odds ratio (OR) and 95% confidence intervals (CIs) of the sarcopenia status and sarcopenia-associated risk factors in the predialysis CKD patients. All tests were two-sided, and p < 0.05 was defined as statistical significance.

RESULTS

Among the 3648 older adults (mean age: 71.9 ± 6.07 years), including 1701 males and 1947 females, 870 (23.9%), 94 (2.58%) and 48 (1.32%) had possible sarcopenia, sarcopenia and severe sarcopenia, respectively. After adjustment, the risk for possible sarcopenia, sarcopenia and severe sarcopenia significantly increased with ageing (OR = 1.11, 1.10 and 1.23; 95% CI = 1.10-1.13, 1.07-1.15 and 1.18-1.30, respectively) and male gender (OR = 2.26, 20.3 and 25.4; 95% CI = 1.87-2.73, 11.5-36.0 and 11.3-57.2, respectively). Compared with KDIGO G1, no significant association between KDIGO G3-5 and the statuses of sarcopenia was observed (OR = 0.97, 0.88 and 0.91; 95% CI = 0.75-1.26, 0.43-1.78 and 0.37-2.27, p = 0.821, 0.718, 0.838, for possible sarcopenia, sarcopenia and severe sarcopenia, respectively). Ageing and male gender indicated a significant risk for higher sarcopenia status in older patients with predialysis CKD (0.027-fold/year and 0.284-fold, respectively) (p < 0.0001).

CONCLUSIONS

This study illuminated the importance of the male sex and the ageing process on the risk of sarcopenia progression in patients with predialysis CKD. Early clinical screening and aggressive treatment for the prevention of higher sarcopenia status in advanced older male adults with predialysis CKD are recommended.

Agreement between the EWGSOP2 and SDOC consensuses for sarcopenia in patients receiving hemodialysis: Findings of a cross sectional analysis from the SARC-HD study

BACKGROUND

Differences in definitions and operational diagnoses for sarcopenia create difficulties in understanding the epidemiology of the disease. We examined the prevalences of sarcopenia using the revised European Working Group on Sarcopenia in Older People (EWGSOP2) and the Sarcopenia Definitions and Outcomes Consortium (SDOC) consensuses and analyzed their level of agreement in patients receiving hemodialysis.

METHODS

Data from the SARCopenia trajectories and associations with clinical outcomes in patients receiving hemodialysis (SARC-HD) multicenter study in Brazil were analyzed. Muscle strength was assessed using handgrip strength, muscle mass by calf circumference, and physical performance by the 4-m gait speed test. Sarcopenia was diagnosed according to both the EWGSOP2 (low muscle strength plus low muscle mass) and the SDOC (low muscle strength plus low physical performance). The Cohen kappa statistic was used to determine the level of agreement between the consensuses.

RESULTS

838 patients (57.8 ± 15.0 years; 61% men) from 19 dialysis units were included. We found similar prevalences of sarcopenia between the consensuses (EWGSOP2, n = 128, 15.3%; SDOC, n = 105, 12.5%) but with weak agreement (50 of 233 patients, 21.5%; κ = 0.34, 95% CI 0.25-0.43). Agreement was also weak within age categories (≥60 years, κ = 0.34; <60 years, κ = 0.15; both P < 0.001). Of the 51 patients diagnosed by the EWGSOP2 criterion as having severe sarcopenia, all but 1 (98.0%) met the SDOC criterion for sarcopenia (κ = 0.61, 95% CI 0.52-0.70). Low muscle strength was more frequently diagnosed using the SDOC than with the EWGSOP2 (52.3% vs 25.9%).

CONCLUSION

We found a weak agreement between the EWGSOP2 and SDOC consensuses for the diagnosis of sarcopenia in patients receiving hemodialysis. Although still weak, agreement was marginally better for older patients. These findings highlight the importance of a global and standardized conceptual diagnosis of sarcopenia.

Development and Validation of a Risk Prediction Model for Sarcopenia in Chinese Older Patients with Type 2 Diabetes Mellitus

Purpose

Sarcopenia is a common prevalent age-related disorder among older patients with type 2 diabetes mellitus (T2DM). This study aimed to develop and validate a nomogram model to assess the risk of incident sarcopenia among older patients with T2DM.

Patients and methods

A total of 1434 older patients (≥ 60 years) diagnosed with T2DM between May 2020 and November 2023 were recruited. The study cohort was randomly divided into a training set (n = 1006) and a validation set (n = 428) at the ratio of 7:3. The best-matching predictors of sarcopenia were incorporated into the nomogram model. The accuracy and applicability of the nomogram model were measured by using the area under the receiver operating characteristic curve (AUC), calibration curve, Hosmer-Lemeshow test, and decision curve analysis (DCA).

Results

571 out of 1434 participants (39.8%) had sarcopenia. Nine best-matching factors, including age, body mass index (BMI), diabetic duration, glycated hemoglobin A1c (HbA1c), 25 (OH)Vitamin D, nephropathy, neuropathy, nutrition status, and osteoporosis were selected to construct the nomogram prediction model. The AUC values for training and validation sets were 0.800 (95% CI = 0.773-0.828) and 0.796 (95% CI = 0.755-0.838), respectively. Furthermore, the agreement between predicted and actual clinical probability of sarcopenia was demonstrated by calibration curves, the Hosmer-Lemeshow test (P > 0.05), and DCA.

Conclusion

Sarcopenia was prevalent among older patients with T2DM. A visual nomogram prediction model was verified effectively to evaluate incident sarcopenia in older patients with T2DM, allowing targeted interventions to be implemented timely to combat sarcopenia in geriatric population with T2DM.

The gut microbiome, chronic kidney disease, and sarcopenia

Sarcopenia is a prevalent condition in patients with chronic kidney disease (CKD), intricately linked to adverse prognoses, heightened cardiovascular risks, and increased mortality rates. Extensive studies have found a close and complex association between gut microbiota, kidney and muscle. On one front, patients with CKD manifest disturbances in gut microbiota and alterations in serum metabolites. These abnormal microbiota composition and metabolites in turn participate in the development of CKD. On another front, altered gut microbiota and its metabolites may lead to significant changes in metabolic homeostasis and inflammation, ultimately contributing to the onset of sarcopenia. The disturbance of gut microbial homeostasis, coupled with the accumulation of toxic metabolites, exerts deleterious effects on skeletal muscles in CKD patients with sarcopenia. This review meticulously describes the alterations observed in gut microbiota and its serum metabolites in CKD and sarcopenia patients, providing a comprehensive overview of pertinent studies. By delving into the intricate interplay of gut microbiota and serum metabolites in CKD-associated sarcopenia, we aim to unveil novel treatment strategies for ameliorating their symptoms and prognosis.

Multi-channel EMG manifestations of upper-extremity muscle coordination imbalance among community-dwelling sarcopenic seniors

BACKGROUND

Sarcopenia is an age-related, insidious, crippling but curable degenerative disease if diagnosed and treated early. However, no accessible and accurate early screening method is available for community settings that does not require specialized personnel. One of the hallmarks of sarcopenia is the pathological changes of muscle fiber type composition and motor unit firing patterns. Surface electromyography (sEMG) may serve as an effective tool for detecting differences between healthy and sarcopenic individuals due to its superior wearability and accessibility compared to other screening methods such as medical imaging and bioimpedance measurements, making it ideal for community-based sarcopenic screening. Our study aims to explore sEMG biomarkers that can be used for screening or diagnosis of sarcopenia.

RESULTS

We collected multi-channel sEMG signals from six forearm muscles of 98 healthy and 55 sarcopenic community-dwelling older adults. Participants performed grasp tasks at 20% and 50% of maximum voluntary contraction (MVC). Hexagons created by various EMG features, normalized with respect to respective MVC, and symmetry analyses were performed to estimate multi-muscle coordination patterns. An innovative index, namely incenter-circumcenter distance of muscle coordination (ICDMC), is proposed to discriminate between the healthy and sarcopenic groups. We utilized non-parametric tests to compare the ICDMC between the two groups, considering a p-value less than 0.05 statistically significant. The results showed that at 20% MVC, ICDMCs from root mean square (RMS), mean absolute value (MAV), slope sign changes (SSC) and wavelength (WL) showed statistically significant differences. More insights of this sEMG manifestation of sarcopenia were revealed by gender- and age-stratifications analyses.

CONCLUSIONS

Our results demonstrated that there are clear sEMG manifestations of altered muscle coordination in sarcopenic patients. More consistent force generation patterns were observed in the sarcopenic group, especially at lower contraction intensities. The novel ICDMC can quantify differences between sarcopenic and healthy muscle. These results warrant further research to further develop more accessible sarcopenia screening strategies in community settings based on electrophysiological measurements such as sEMG.

Low Skeletal Muscle Density Assessed by Abdominal Computerized Tomography Predicts Outcome in Children With Chronic Kidney Disease

OBJECTIVES

Skeletal muscle loss and abnormal fat distribution are predictors of poor clinical outcomes in adults with chronic kidney disease (CKD). However, the relationship between body composition (muscle mass and adipose tissue) and prognosis in children with CKD has not been well elucidated.

METHODS

The retrospective single-center study enrolled children with CKD and healthy group who underwent an abdominal computerized tomography examination and compared the body composition of the third lumbar spine (L3) between the 2 groups. We defined the primary outcome as hemodialysis, peritoneal dialysis, kidney transplantation, or death. Logistic regression analysis was applied to assess the connection between low skeletal muscle density (SMD) and clinical and demographic variables. Multivariate Cox regression analysis was used to evaluate the risk factors for progression to the primary outcome. Kaplan-Meier survival analysis was performed to compare the effect of different body composition on event-free survival rate.

RESULTS

Thirty-two patients with CKD [estimated glomerular filtration rate: 14.89 (8.86, 29.88) (mL/min/1.73 m2)] and 66 heathy subjects [estimated glomerular filtration rate: 135.72 (121.70, 161.29) (mL/min/1.73 m2)] were recruited in our study. From the assessment of body composition assessed by computerized tomography, skeletal muscle area, SMD, and skeletal muscle index in the CKD group was lower than those in the healthy group (P < .05). On the other hand, visceral fat area and visceral fat index in the CKD group were significantly higher than those in the healthy group (P < .05). In logistic regression analysis, triglyceride (odds ratio: 8.635, 95% confidence interval (CI): 1.153-64.687) was independently associated with low SMD. After adjusting clinical data and body composition, high serum albumin (hazard ratio: 0.873, 95% CI: 0.798-0.955) and high SMD (hazard ratio: 0.895, 95% CI: 0.822-0.974) were protective factors for delaying renal failure. Based on the Kaplan-Meier analysis, only the group with low SMD had lower event-free survival in comparison to the reference group (P < .05).

CONCLUSIONS

These findings suggest that there is significant skeletal muscle loss and decrease in SMD in CKD children. Notably, low SMD is indicative of poor prognosis in CKD children.

Patients With Type 2 Diabetes Mellitus and Early Diabetic Kidney Disease Exhibit Lower Computed Tomography-measured Skeletal Muscle Attenuation Values: A Propensity Score-matched Study

OBJECTIVE

To investigate the association between computed tomography-measured quality characteristics of skeletal muscle (SM) and early diagnosis of diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

This retrospective study included patients diagnosed with T2DM, with and without early DKD, between January 2019 and December 2021. To reduce potential bias, propensity score matching (PSM) was performed. The area and computed tomography attenuation values for SM and different abdominal adipose depots were measured. After PSM, logistic and multiple linear regression analyze were performed to analyse risk factors for early DKD.

RESULTS

A total of 267 patients were enrolled (mean age, 61.67 years ± 10.87; 155 men) and divided into two groups: T2DM with early DKD (n = 133); and T2DM without DKD (n = 134). After PSM, 230 patients were matched (T2DM with early DKD [n = 115]; and T2DM without DKD [n = 115]), with no statistical differences in general characteristics between the two groups (P > .05). In multivariate logistic regression analysis, high-density lipoprotein cholesterol (odds ratio [OR] 0.14; 95% confidence interval [CI] 0.04-0.49; P = .002), uric acid (OR 1.01; 95% CI 1.00-1.01; P = .006), and SM attenuation value (OR 0.94; 95% CI 0.90-0.98; P = .003) were independent risk factors for early DKD. Multiple linear regression analysis revealed significant correlations between SM attenuation value and cystatin C (β = -0.39, P = .004), urine albumin-to-creatinine ratio (β = -0.26, P = .026), and estimated glomerular filtration rate (β = 0.31 P = .009) after adjustment for confounders.

CONCLUSION

Patients with T2DM and lower SM attenuation values may exhibit a higher risk for early DKD than those with higher values, which provides a potential imaging biomarker for early DKD diagnosis.

Ten tips on how to manage obesity in the presence of CKD

Patients with chronic kidney disease are frequently facing the challenge of weight reduction. Finding a weight loss strategy is on the one hand essential to reduce the co-morbidity risks in CKD but remains complex due to the metabolic abnormalities with declining renal function. Here, we provide ten tips to support our CKD patients on their journey, focussing on dietary and behavioural habits and health professional supportive therapies.

Myosteatosis: an underrecognized risk factor for mortality in non-dialysis chronic kidney disease patients

BACKGROUND

Low muscle mass quantity and quality (myosteatosis) can be evaluated by computed tomography (CT) by measuring skeletal muscle area and muscular attenuation, respectively, at the third lumbar vertebra. We aimed to define cut-off points of skeletal muscle area and muscular attenuation to predict mortality in non-dialysis chronic kidney disease (CKD) patients.

METHODS

We conducted a retrospective study including non-dialysis CKD patients over two years, who underwent an opportunistic computed tomography within a two year period, and for whom creatinine was measured within 90 days of CT. Skeletal muscle area was normalized for stature to calculate the skeletal muscle index. Area under the receiver operating characteristic (AuROC) curve and Youden's index were used, to identify the cut-point, separately according to sex.

RESULTS

One hundred sixty-seven patients (50.9% male, mean age of 68.3 ± 16.4 years) were included, most with CKD stages 3 and 4. During a median follow-up of 4.9 (4.2) years, 39 (23.4%) patients died. Muscular attenuation showed a better ability to predict mortality (AuROC curve 0.739 [95% CI 0.623-0.855] in women and 0.744 in men [95% CI 0.618-0.869]) than skeletal muscle index (AuROC curve 0.491 [95% CI 0.332-0.651] in women and 0.711 [95% CI 0.571-0.850] in men). For muscular attenuation, the best cut-off values to predict mortality were 27.56 Hounsfield units in women and 24.58 Hounsfield units in men. For skeletal muscle index, the best cut-off values were 38.47 cm2/m2 in women and 47.81 cm2/m2 in men. In univariable Cox-regression both low muscle mass and myosteatosis were associated with increased mortality. In multivariable Cox-regression models only myosteatosis maintained a significant association with mortality (Hazard Ratio 2.651 (95% CI 1.232-5.703, p = 0.013)).

CONCLUSIONS

We found sex-specific cut-off values for muscle parameters using CT analysis in non-dialysis CKD patients that were associated with mortality. In this population, myosteatosis may be more closely associated with mortality than muscle quantity.

Muscle Mass and Muscle Strength in Non-Dialysis-Dependent Chronic Kidney Disease Patients

Background: Sarcopenia is a state with a progressive and generalized loss of skeletal muscle mass and strength. However, muscle strength and muscle mass are different features, which are usually not studied separately. The aim of the study was to investigate anthropometric and clinical correlates and sources of variation in both skeletal muscle mass and muscle strength in chronic kidney disease (CKD). Methods: The study sample consisted of 84 patients with an estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2. Muscle strength was estimated by measuring hand grip strength (HGS). Muscle quantity was measured with bioimpedance spectroscopy (BIS). Serum creatinine, urea, uric acid (UA), and albumin were measured as well. Results: Appendicular skeletal muscle mass (ASM) significantly and positively correlated with body mass, NH weight (normally hydrated weight), height, body mass index (BMI), lean tissue mass (LTM), lean tissue index (LTI), fat mass (FM), and fat tissue index (FTI), and was negatively associated with hydration status. HGS significantly and positively correlated with body mass, NH weight, height, LTM, LTI, and ASM, and was negatively associated with UA and urea. After adjustment for age, sex, and height, HGS remained significantly and negatively related with UA and hydration status. Conclusions: In CKD patients, ASM is determined by anthropometric parameters, but HGS is determined by both anthropometric and clinical variables specific for CKD. In order to study the determinants of HGS in CKD, relationships with HGS should be adjusted for anthropometric variables.

Impact of Psoas Muscle Area Index on Short- and Mid-Term Mortality in Patients Undergoing Valve Surgery for Infective Endocarditis: A Retrospective Analysis

Background: Sarcopenia, characterized by the loss of skeletal muscle mass, is an emerging comorbidity associated with poor outcomes in cardiovascular surgery. Its impact on mortality in patients undergoing valve surgery for infective endocarditis (IE) remains underexplored. This study investigates the relationship between sarcopenia, measured by the Psoas muscle area index (PMAi), and mortality in patients with IE undergoing valve surgery. Materials and Methods: We retrospectively analyzed 68 patients with IE who underwent valve surgery at a tertiary care center from 2013 to 2021. Sarcopenia was defined as being in the lowest quartile of PMAi, measured via preoperative computed tomography (CT). Baseline characteristics, survival outcomes, and factors influencing mortality were analyzed using Kaplan-Meier survival curves and Cox proportional hazards regression. The predictive value of PMAi for 1-year and 3-year mortality was assessed via receiver operating characteristic (ROC) curves. Results: Sarcopenia was strongly associated with increased mortality at both 1-year (HR: 0.378, p = 0.010) and 3-year follow-ups (HR: 0.457, p = 0.012). Female sex (OR: 275.748, p < 0.001) and older age (OR: 9.995, p = 0.003) were significant predictors of sarcopenia. Chronic kidney insufficiency (CKI) and the use of heart failure medication therapy also significantly impacted survival outcomes. Conclusions: Sarcopenia is a strong independent predictor of short- and mid-term mortality in patients undergoing valve surgery for IE. Routine radiological assessment of sarcopenia using PMAi could improve risk stratification and guide preoperative interventions. Tailored management strategies, especially in older women and patients with CKI, may enhance outcomes in this high-risk population.

Effects of plasminogen activator inhibitor-1 deficiency on bone disorders and sarcopenia caused by adenine-induced renal dysfunction in mice

Chronic kidney disease (CKD) is a significant global health issue and often involves CKD-mineral and bone disorder (MBD) and sarcopenia. Plasminogen activator inhibitor-1 (PAI-1) is an inhibitor of fibrinolysis. PAI-1 has been implicated in the pathogenesis of osteoporosis and muscle wasting induced by inflammatory conditions. However, the roles of PAI-1 in CKD-MBD and sarcopenia remain unknown. Therefore, the present study investigated the roles of PAI-1 in bone loss and muscle wasting induced by adenine in PAI-1-deficient mice. CKD was induced in PAI-1+/+ and PAI-1-/- mice by administration of adenine for ten weeks. Muscle wasting was assessed by grip strength test, quantitative computed tomography (CT) analysis and muscle weight measurement. Osteoporosis was assessed by micro-CT analysis of femoral microstructural parameters. PAI-1 deficiency did not affect adenine-induced decreases in body weight and food intake or renal dysfunction in male or female mice. PAI-1 deficiency also did not affect adenine-induced decreases in grip strength, muscle mass in the lower limbs, or the tissue weights of the gastrocnemius, soleus, and tibialis anterior muscles in male or female mice. PAI-1 deficiency aggravated trabecular bone loss in CKD-induced male mice, but significantly increased trabecular bone in CKD-induced female mice. On the other hand, PAI-1 deficiency did not affect cortical bone loss in CKD-induced mice. In conclusion, PAI-1 is not critical for the pathophysiology of CKD-MBD or CKD-induced sarcopenia in mice. However, PAI-1 may be partly related to bone metabolism in trabecular bone in the CKD state with sex differences.

Performance of SARC-F and SARC-CalF scores to predict risk of mortality in hemodialysis patients: a cohort study

This study aimed to evaluate the association between the questionnaires SARC-F and SARC-CalF with risk of mortality in patients undergoing hemodialysis (HD). A cohort study, with patients on HD age ≥ 18 years, both sex, between June 2019 and April 2023. Body composition (anthropometry and bioelectrical impedance), muscle functional (handgrip strength and gait speed), screening of sarcopenia using the SARC-F and SARC-CalF, nutritional status and laboratory data were assessed. Follow-up for mortality up to 47 months. The sample consisted of 243 participants and the prevalence of risk of sarcopenia using SARC-F and SARC-CalF were 30% and 45%, respectively; 65 died for all reasons and three patients were censored due to transplantation. Multivariate analysis identified SARC-CalF as predictor of mortality in HD patients [hazard ratio 1.96; 95% CI (1.01-3.79); p = 0.04]. The survival analysis showed that there was a significant difference in the survival curves among the groups stratified by SARC-F and SARC-CalF for log-rank test. A higher specificity was found for SARC-CalF than SARC-F (80% vs. 77%) in receiver operating characteristic (ROC) curve. Both questionnaires were associated with anthropometric, parameters of body composition, physical measurements, and SARC-CalF was predictor of risk for mortality in HD patients.

Pica is associated with lower willingness to change negative habits of diet and exercise, inadequate lifestyle, and less healthful food consumption in dialysis

Background

In dialysis patients, on the one hand unwillingness to change negative lifestyle patterns is associated with worse nutritional status and unhealthy lifestyle, whereas on the other, pica may be highly prevalent. However, it is not known whether pica is associated with unwillingness to change negative lifestyle behaviors, as well as with consumption of different types of foods. This study aimed to investigate this issue.

Methods

This is a cross-sectional study in dialysis patients. Lifestyle was assessed using the self-administered Instrument to Measure Lifestyle Questionnaire (IMEVID). Pica diagnosis was established according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. A food frequency questionnaire was performed and self-reported willingness to change was determined by a trans-theoretical model staging inventory.

Results

Compared with patients without pica, those with pica (particularly hard pica) had lower willingness to change unhealthy behavior in the case of diet (22% vs. 46% in precontemplation/contemplation stages, respectively) and exercise (43% vs. 62% in precontemplation/contemplation stages, respectively). Patients with hard pica had significantly (p < 0.05) lower scores in almost all dimensions of the lifestyle questionnaire than those in the no pica group: diet (23.9 vs. 26.8, respectively), physical activity (5.5 vs. 7, respectively), knowledge of disease (5.7 vs. 6.4, respectively), emotion management (6.6 vs. 8, respectively) and adherence to treatment (13.4 vs. 14.7, respectively), but not in the consumption of tobacco and alcohol. Compared to patients with no pica, those with hard pica ate vegetables and fruits less frequently, and dairy products, fried foods and soda more frequently.

Conclusions

Pica was more frequently observed in patients with lower willingness to change negative habits of diet and exercise, in those who had more unhealthy behaviors in diet, exercise and emotion management dimensions and adherence to treatment, as well as in those who ate less frequently healthful foods and more frequently unhealthy foods.

Dietary Needs, Barriers, and Facilitators Among Patients on Hemodialysis and Their Caregivers: The GoodRENal Project in Spain

OBJECTIVE

Dietary restrictions are common in patients undergoing hemodialysis (HD). These restrictions result in a complex diet that becomes difficult for patients to understand and to follow. Therefore, we aimed to identify dietary needs, barriers, and facilitators that influence the adherence to dietary recommendations as perceived by patients on HD and their caregivers.

METHODS

Seventy-two Spanish patients on HD and 57 caregivers participated in this explorative study by replying a questionnaire consisting of 20 and 10 questions respectively. The responses were assessed using a Likert scale varying from 1 to 5 (strongly agree, agree, neither disagree or disagree, disagree, strongly disagree, respectively) to evaluate the perception of patients and caregivers regarding dietary needs, barriers, and facilitators to adhere to the recommended diet. For analysis purposes, the responses were grouped in 3 categories (agree, neither agree or disagree, disagree).

RESULTS

Seventy percent of the patients agreed that knowing the food sources of potassium, protein and phosphate was a need for them to know to be able to adhere to the dietary recommendations. Moreover, patients stated that not being able to eat what they liked, and feeling thirsty, were important barriers. For caregivers, the support of a renal dietitian was mentioned as an important facilitator to assist those they cared for to adhere to the diet.

CONCLUSIONS

Knowing food sources of potassium, phosphate, and protein, exploring foods patients like to eat and adjusting fluid intake to avoid feeling thirsty were identified as important by the patients. These findings can be used to develop strategies and educational material to improve the dietary adherence in patients undergoing HD. Moreover, the presence of a renal dietitian was identified as an important resource by the caregivers.

Changes in Bone Mineral Density in Patients With Non-dialysis-Dependent Chronic Kidney Disease Are Associated With Body Composition

OBJECTIVE

Chronic kidney disease (CKD) and low bone mineral density (BMD) are highly prevalent and can co-exist. Parameters of mineral metabolism are associated with BMD in CKD, but other contributing factors may contribute. The aim of this study was to assess changes in BMD and its determinants in patients with nondialysis-dependent CKD (NDD-CKD).

METHODS

Body composition and biochemical profiles were assessed in a retrospective hospital-based cohort study of patients with NDD-CKD. BMD, lean soft tissue (LST), appendicular LST (ALST), and percentage fat mass were assessed by dual-energy X-ray absorptiometry. The ALST index (ALSTI, ALST/height2) and load-capacity index (LCI, fat mass/LST) were calculated. Low BMD was defined as T-score ≤ -1.0.

RESULTS

The mean time between assessments was 2.8 ± 1.3 years; 46 patients were included. A reduction in renal function was observed. Changes in body composition included reductions in ALST (P = .031), ALSTI (P = .021), a trend for BMD (P = .053), and an increase in percentage fat mass (P = .044) and LCI (P = .032). Females had a reduction in BMD (P = .034), ALST (P = .026), and ALSTI (P = .037). Patients with low BMD at baseline had lower LST (P = .013), ALST (P = .023), and percentage fat mass (P = .037) than those with normal BMD. Additionally, reductions in LST (P = .041), ALST (P = .006), and ALSTI (P = .008) were observed in patients who had low BMD at baseline, while no significant changes in body composition were observed in those with normal BMD at baseline. The following body composition parameters at baseline were determinants of BMD status at follow-up: LST (odds ratio [OR]: 0.899, 95% confidence interval [CI]: 0.829-0.976, P = .010), ALST (OR: 0.825, 95% CI: 0.704-0.967, P = .017), and ALSTI (OR: 0.586, 95% CI: 0.354-0.968, P = .037), independent of fat mass and LCI.

CONCLUSIONS

Detrimental body composition changes were observed without changes in body weight; these were more significant in females. Moreover, this is the first longitudinal study showing a protective effect of LST against BMD loss in patients with NDD-CKD.

Cardiac dysfunction in dialysing adults with end-stage kidney disease is associated with exercise intolerance: A pilot observational study

People with end-stage kidney disease (ESKD) often exhibit impaired cardiac structure and function, which may contribute to poor exercise capacity. This study used multimodal exercise testing to investigate the central and peripheral mechanisms of exercise limitation in adults with ESKD, also comparing in-centre hemodialysis (ICHD) to home hemodialysis (HHD). Seventeen adults (55.5 ± 14.5 years; n = 14 male; n = 12 HHD) participated. Resting cardiac examinations, followed by submaximal cycling cardiopulmonary exercise testing (CPET) and functional exercise testing, revealed cardiac structural abnormalities (increased left ventricular mass) and cardiac injury. Aerobic fitness in adults with ESKD was low, with pulmonary oxygen uptake (V̇O2) at the gas exchange threshold (GET) occuring at 39 ± 8% predicted V̇O2peak. O2 pulse, an estimate of stroke volume (SV), was higher in HHD at rest (p = 0.05, ES = 0.58) and during unloaded cycling (p = 0.05, ES = 0.58) compared to ICHD. However, thoracic bioreactance derived SV at the GET was significantly higher in adults receiving ICHD versus HHD (p = 0.01, ES = 0.74). In adults with ESKD, cardiac output was positively associated with V̇O2 at the GET (r = 0.61, p = 0.04). This study highlights prevalent exercise dysfunction in adults with ESKD undergoing dialysis, with potential distinct differences between in-centre and home hemodialysis, mechanistically linked to underlying cardiac abnormalities.

Assessing Patients beyond the Simple Optics of BMI: The Concomitant Role of Sarcopenia and BMI in Predicting Kidney Transplant Outcomes

BACKGROUND

Body composition is associated with prognosis in many clinical settings, and patients undergoing kidney transplantation are often high risk with multiple comorbidities. We aimed to assess the effect of sarcopenia and body composition on transplant outcomes.

METHODS

We performed a retrospective analysis of 274 kidney transplants with CT scans within 3 years of transplantation. The skeletal muscle index (SMI) at the L3 vertebrae was used to evaluate sarcopenia (SMI < 40.31 cm2/m2 in males, <30.88 cm2/m2 in females). Sarcopenia, body mass index (BMI), and the visceral-to-subcutaneous-fat ratio (VSR) were assessed separately. We also used a composite BMI/sarcopenia measurement in four patient groups: BMI < 25/Non-Sarcopenic, BMI < 25/Sarcopenic, BMI > 25/Non-Sarcopenic, and BMI > 25/Sarcopenic. The outcomes measured were eGFR (1 and 3 months; and 1, 3, and 5 years), delayed graft function (DGF), rejection, major adverse cardiovascular events (MACE), and post-operative complications.

RESULTS

Sarcopenia was associated with an increased 1-year risk of MACE (OR 3.41, p = 0.036). BMI alone had no effect on function, DGF, MACE, or on other complications. High VSR was associated with a lower risk of DGF (OR 0.473, p = 0.016). When sarcopenia and BMI were assessed together, the BMI > 25/sarcopenic patients had the poorest outcomes, with increased risk of MACE (OR 26.06, p = 0.001); poorer eGFR at 1, 3, 12, and 36 months; (p < 0.05 at all timepoints), and poorer graft survival (p = 0.002).

CONCLUSIONS

Sarcopenia alone is associated with an increased risk of MACE. Overweight sarcopenic patients are additionally at increased risk of graft loss and have poorer graft function for up to three years.

Proteomic analysis of endothelial cells and extracellular vesicles in response to indoxyl sulfate: Mechanisms of endothelial dysfunction in chronic kidney disease

AIMS

Cardiovascular pathology is the main cause of death in chronic kidney disease (CKD) patients. CKD is associated with the accumulation of uremic toxins in the bloodstream, and indoxyl sulfate (IS) is one of the most abundant uremic toxins found in the blood of CKD patients. We conducted an in vitro study to assess the mechanisms underlying the IS-induced endothelial dysfunction that could lead to cardiovascular diseases. We also studied their extracellular vesicles (EVs) owing to their capacity to act as messengers that transmit signals through their cargo.

MAIN METHODS

EVs were characterized by nanoparticle tracking analysis, transmission electron microscopy, flow cytometry, and tetraspanin expression. Cell lysates and isolated EVs were analyzed using liquid chromatography coupled with mass spectrometry, followed by Gene Set Enrichment Analysis to identify the altered pathways.

KEY FINDINGS

Proteomic analysis of endothelial cells revealed that IS causes an increase in proteins related to adipogenesis, inflammation, and xenobiotic metabolism and a decrease in proliferation. Extracellular matrix elements, as well as proteins associated with myogenesis, response to UV irradiation, and inflammation, were found to be downregulated in IS-treated EVs. Fatty acid metabolism was also found to be increased along with adipogenesis and inflammation observed in cells.

SIGNIFICANCE

The treatment of endothelial cells with IS increased the expression of proteins related to adipogenesis, inflammation, and xenobiotic metabolism and was less associated with proliferation. Furthermore, EVs from cells treated with IS may mediate endothelial dysfunction, since they present fewer extracellular matrix elements, myogenesis, inflammatory factors, and proteins downregulated in response to UV radiation.

Muscle mass dynamics is independently associated with long-term liver-related mortality in patients with cirrhosis

Objectives

Sarcopenia has a detrimental impact on the prognosis of individuals with liver cirrhosis, however, the clinical significance of alterations in muscle mass remains uncertain. This study aims to investigate the influence of loss of skeletal muscle mass (LSMM) on the prognostic outcomes among patients diagnosed with cirrhosis.

Methods

In this retrospective analysis, a total of 158 individuals with cirrhosis who visited our hospital during the period from January 2018 to August 2023 were included. Computed tomography was utilized to measure the cross-sectional area of the skeletal muscles at the level of the third lumbar vertebra. This measurement enabled the determination of the skeletal muscle index for the purpose of diagnosing sarcopenia. The annual relative change in skeletal muscle area (ΔSMA/y) was calculated for each patient, and LSMM was defined as ΔSMA/y < 0. To assess the risk factors associated with liver-related mortality, a competing risk model was applied.

Results

Of the 158 cirrhotic patients, 95 (60.1 %) patients were identified as LSMM. The median of ΔSMA/y% was -0.9 (interquartile range [IQR], -3.8, 1.6) in all patients. Chronic kidney disease (CKD) was confirmed as a risk factor of LSMM. During a median follow-up period of 68.1 (IQR, 43.5, 105.0) months, 57 patients (36.1 %) died due to the liver-related diseases. The competing risk model found that LSMM was significantly associated with liver-related mortality in cirrhotic patients (hazard ratio [HR], 1.86; 95 % CI, 1.01-3.44, p = 0.047). Cumulative survival was significantly higher in patients without LSMM than in those with LSMM (p = 0.004). Survival rates at 1-, 3-, and 5-years were 96.8 %, 81.0 %, and 65.1 %, respectively, in patients without LSMM, and 97.9 %, 80.0 %, and 56.8 %, respectively, in patients with LSMM.

Conclusion

The utilization of LSMM can be valuable in the prediction of liver-related mortality among individuals diagnosed with liver cirrhosis. Paying attention to the management of skeletal muscle might play a role in enhancing the prognosis of patients with cirrhosis.

Clinical relevance statement

This study provides an additional indicator-LSMM for clinicians to help predict the liver-related mortality in patients diagnosed with cirrhosis.

Low thoracic skeletal muscle is a risk factor for 6-month mortality of severe community-acquired pneumonia in older men in intensive care unit

BACKGROUND

Patients with severe community-acquired pneumonia (sCAP) admitted to the intensive care unit (ICU) often exhibit muscle catabolism, muscle weakness, and/or atrophy, all related to an increased morbidity and mortality. However, the relationship between thoracic skeletal muscle mass and sCAP-related mortality has not been well-studied. Early recognition of sarcopenia in ICU patients with sCAP would benefit their prognosis.

METHODS

A retrospective study was conducted in Taizhou Hospital of Zhejiang Province, involving 101 patients with sCAP admitted in the ICU between December 2022 and February 2023. We measured the cross-sectional aera of the pectoralis, intercostal, paraspinal, serratus, and latissimus muscles at the T4 vertebral level (T4CSA) using chest computed tomography. Discriminatory thresholds were established by performing receiver operating characteristic curve analysis, with a designated cutoff value of 96.75 cm2 for male patients. This cohort was classified into mortality and survival groups based on a 6-month post-admission outcome. Univariate and multifactorial logistic regression analyses were performed to validate the correlation between low thoracic skeletal muscle area and prognostic outcomes.

RESULTS

The mean age of the patients was 75.39 ± 12.09 years, with an overall 6-month mortality of 73.27%. T4CSA of the 6-month survival group was significantly larger than that in the mortality group for overall cohort. The T4CSA in the survival group was significantly larger than that in the mortality group (104.29 ± 23.98cm2 vs. 87.44 ± 23.0cm2, p = 0.008). T4CSA predicted the 6-month mortality from sCAP in males with an AUC of 0.722 (95% confidence interval (CI), 0.582-0.861). The specificity and sensitivity were 71.4% and 71.1%, respectively, (p < 0.05). No significant difference was observed between the two groups in terms of T4CSA.

CONCLUSIONS

This study revealed that low thoracic skeletal muscle mass increased the risk of all-cause 6-month mortality in ICU patients with sCAP, particularly among male patients.

The value of multi-modal ultrasound in the assessment of sarcopenia in maintenance hemodialysis patients

INTRODUCTION

Sarcopenia is one of the common complications in maintenance hemodialysis (MHD) patients and is associated with poor prognosis. We aimed to study the validity and reliability of ultrasound in the assessment of sarcopenia in MHD patients.

METHODS

MHD patients were categorized into the sarcopenia group and the non-sarcopenia group according to the diagnostic criteria of the Asian Working Group on Sarcopenia (AWGS) 2019. Ultrasonography of the left medial head of the gastrocnemius muscle was performed in MHD and healthy controls to obtain muscle thickness (MT), pinnation angle (PA), fascicle length (FL), cross-sectional area (CSA), echo intensity (EI), elastic modulus (E), shear wave velocity (SWV), and microvascular velocity (MV). Compare the differences in ultrasound parameters among different groups, and determine the cut-off values suitable for diagnosing sarcopenia in MHD patients.

RESULTS

The MT, CSA, PA, and MV in the sarcopenia group were lower than those in the non-sarcopenia group and the control group; while the EI was higher, the FL of the sarcopenia group was lower than that of the non-sarcopenia group, while the E and SWV of the sarcopenia group were higher than those of the control group. Receiver operating characteristic curve analyses indicated that ultrasound combined index had a good diagnostic value, model Y = 13.511-0.121*MT-0.609*CSA-0.172*PA+0.011*EI-2.205*MV(P < 0.05), with a cut-off value of 0.69.

CONCLUSIONS

Multi-modal ultrasound is a safe, non-invasive, and real-time imaging examination method, and can provide information on muscle structure, stiffness, and perfusion, which is expected to be a promising potential tool for predicting sarcopenia in MHD patients.

Sarcopenia and Associated Factors in Adults Aged 40 and Above: A Study Conducted in Primary Healthcare

INTRODUCTION

Sarcopenia, characterized by progressive skeletal muscle loss, has emerged as a significant public health concern, with a global prevalence of 10-27%. While traditionally studied in geriatric populations, recent evidence indicates its impact on individuals aged 40 and above, with early manifestations of muscle decline. Primary care settings play a pivotal role in the early identification and management of sarcopenia, facilitating timely diagnosis and intervention. This study aims to evaluate the prevalence of sarcopenia and its associated factors among individuals aged 40 and above attending a family medicine outpatient clinic.

METHODS

A cross-sectional study was conducted in a family medicine outpatient clinic, including participants aged 40 and above. Participants underwent handgrip strength measurements, calf circumference measurements, and a 4-m walking test. Based on the criteria of the European Working Group on Sarcopenia in Older People 2 (EGSWOP2), individuals with sarcopenia and those at risk of sarcopenia were identified. The Mini Nutritional Assessment (MNA) was used to assess nutritional status. Sociodemographic characteristics, comorbidities, and laboratory values were recorded. A comparison was made between individuals with normal muscle strength and those at risk of sarcopenia.

RESULTS

Among 213 individuals, 33 (15.4%) were at risk of sarcopenia (probable sarcopenia), and 12 (5.6%) were diagnosed with sarcopenia. There was a negative correlation observed between age and muscle strength (r=-0,339, p<0,001), and positive correlation was found between muscle strength and MNA score (r=0.301, p<0.001). Individuals with higher education and income levels exhibited higher muscle strength. Participants at risk of sarcopenia had higher prevalence rates of comorbidities such as diabetes mellitus (DM), chronic kidney disease, and cardiovascular disease (p=0.20, p<0.01, p=0.015, respectively).

CONCLUSION

Our study highlights the prevalence and associated factors of sarcopenia in individuals aged 40 and above emphasizing the need for screening and intervention strategies in primary care settings. The study findings support the role of primary care in addressing sarcopenia and improving patient outcomes.

Analysis of Risk Factors of Sarcopenia in Patients with Maintenance Hemodialysis and Its Correlation with Emotional Status and Quality of Life

Objective

Sarcopenia is more common in maintenance hemodialysis (MHD) patients, and the aim of this study is to analyze the risk factors associated with sarcopenia in MHD patients, along with its correlation to emotional status and quality of life.

Methods

This is a cross-sectional cohort study. A total of 111 MHD patients who were treated in the Department of Nephrology of our hospital were selected as the study subjects by convenience sampling. The quality of life and emotional status were evaluated by health survey scale (SF-36), self-rating anxiety scale (SAS) and self-rating depression scale (SDS). Regression analysis was used to explore the influencing factors of sarcopenia. Correlation analysis was used to investigate the correlation between sarcopenia and quality of life and emotional status.

Results

The prevalence of sarcopenia was 59.8%. The results showed that age, gender, body mass index (BMI), dialysis time, economic status, marital status and pre-dialysis creatinine were significant factors affecting the development of sarcopenia in hemodialysis patients (p<0.05). The SF-36 total score was significantly lower in the sarcopenia group (72.05±12.28 vs 78.03±10.55) than in the non-sarcopenia group, but the anxiety scale score (52.97±4.67 vs 36.2±3.36) and depression scale score (57.67±4.58 vs 38.71±3.77) were significantly higher than those in the non-sarcopenia group (p< 0.001). Correlation analysis showed that sarcopenia was positively correlated with SAS and SDS scores and negatively correlated with SF-36 total score (p < 0.05).

Conclusion

The risk of sarcopenia was higher among MHD patients who were older, male, single, with a longer MHD duration, lower economic status, lower BMI, comorbid diabetes and lower levels of creatinine.

Association between pro-vegetarian dietary pattern and the risk of protein-energy wasting and sarcopenia in patients with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is characterized by structural abnormalities in nephrons, loss of functional nephrons, and impaired renal excretory function. A pro-vegetarian dietary pattern (PDP) is a gradual and progressive approach to vegetarianism. The current study aimed to assess the association between PDP and the odds of protein-energy wasting (PEW) and sarcopenia in patients with CKD.

METHODS

The present cross-sectional study was conducted on kidney disease patients (n = 109) referred to two clinics in Shiraz, Iran. The diagnosis of sarcopenia and PEW was made according to the guidelines of the Asian Working Group for Sarcopenia (AWGS) and the International Society of Renal Nutrition and Metabolism (ISRNM) criteria, respectively. The participants' dietary intake was evaluated using a 168-item semi-quantitative food frequency questionnaire (FFQ). For PDP index calculation, plant and animal food sources were categorized into 12 subgroups. The association between sarcopenia and PEW with PDP was evaluated using logistic regression.

RESULTS

The PDP was significantly associated with a lower risk of PEW in the second tertile compared to the first in the crude model (odds ratio (OR) = 0.225; confidence interval (CI): 0.055-0.915; p-value = 0.037). After adjusting for potential confounders, lower significant odds of PEW were observed in the second and last tertiles of PDP compared to the first (T2: OR = 0.194; CI: 0.039-0.962; p-value = 0.045, and T3: OR = 0.168; CI: 0.030-0.950; p-value = 0.044). In contrast, no significant relationship was observed between PDP and the odds of sarcopenia (p-value ˃ 0.05).

CONCLUSIONS

Overall, the findings indicated that greater adherence to PDP was negatively associated with the odds of PEW. Additionally, the results showed no association between PDP and the odds of sarcopenia. Further studies are needed to support these findings.

The association of appendicular skeletal muscle mass with anthropometric, body composition, nutritional, inflammatory, and metabolic variables in non-dialysis-dependent chronic kidney disease men

Background

Muscle atrophy affects more than 50% of patients with chronic kidney disease (CKD) and is associated with increased morbidity and mortality. It is crucial to understand the mechanisms involved in the muscle atrophy in CKD and search for specific determinants of skeletal muscle mass loss, especially those which are available in everyday medical practice. This study aimed to evaluate the association between appendicular skeletal muscle mass (ASM) and anthropometric, body composition, nutritional, inflammatory, metabolic, and kidney function variables in non-dialysis-dependent CKD men.

Methods

A total of 85 men with CKD and eGFR lower than 60 mL/min/1.73 m2 were included in the cross-sectional study: 24 participants with eGFR 59-45 mL/min/1.73 m2, 32 individuals with eGFR 44-30 mL/min/1.73 m2, and 29 men with eGFR ≤29 mL/min/1.73 m2. ASM was estimated by bioimpedance spectroscopy (BIS) with the use of a Body Composition Monitor (BCM). To evaluate ASM from BCM, Lin's algorithm was used. Among anthropometric parameters, height, weight, and body mass index (BMI) were measured. Serum laboratory measurements were grouped into kidney function, nutritional, inflammatory, and metabolic parameters.

Results

ASM was significantly associated with anthropometric and body composition variables. According to the anthropometric parameters, ASM correlated positively with weight, height, and BMI (p < 0.001 and r = 0.913, p < 0.001 and r = 0.560, and p < 0.001 and r = 0.737, respectively). Among body composition variables, ASM correlated significantly and positively with lean tissue mass (LTM) (p < 0.001, r = 0.746), lean tissue index (LTI) (p < 0.001, r = 0.609), fat mass (p < 0.001, r = 0.489), and fat tissue index (FTI) (p < 0.001, r = 0.358). No other statistically significant correlation was found between ASM and kidney, nutritional, metabolic, and inflammatory variables.

Conclusion

In male patients with CKD stages G3-G5 not treated with dialysis, ASM correlates significantly and positively with anthropometric and body composition parameters such as weight, height, BMI, LTM, LTI, fat mass, and FTI. We did not observe such relationship between ASM and kidney function, nutritional, metabolic, and inflammatory variables.

The U-shape relationship between insulin resistance-related indexes and chronic kidney disease: a retrospective cohort study from National Health and Nutrition Examination Survey 2007-2016

BACKGROUND

There is ongoing debate on the correlation between chronic kidney disease (CKD) and insulin resistance (IR)-related indices. Our objective was to explore the prognostic ability of IR-related indexes for the prevalence of CKD, as well as the mortality from all causes and cardiovascular disease (CVD) in CKD patients.

METHODS

The data used in this study came from the National Health and Nutrition Examination Survey (NHANES). Binary logistic regression analysis, Cox proportional hazards model, and restricted cubic spline (RCS) were used to analyze the relationship between IR-related indexes, including metabolic score of IR (METS-IR), homeostatic model assessment for IR (HOMA-IR), triglyceride glucose index (TyG), triglyceride glucose-waist-to-height ratio (TyG-WHtR), triglyceride glucose-body mass index (TyG-BMI), with CKD and its all-cause mortality and CVD mortality. Subgroup analysis was performed to test the stability of the results. Finally, the predictive power of IR-related indexes for CKD was tested by the receiver operating characteristic (ROC) curve.

RESULTS

Among the recruited 10,660 participants, 15.42% were CKD patients. All IR-related indexes were found to be nonlinearly correlated to the prevalence of CKD in the study. When the TyG index was higher than 9.05, it was positively associated with CKD (OR: 1.77, 95% CI 1.44-2.18). Moreover, increased TyG-WHtR level was correlated with a greater prevalence of CKD when it was higher than 4.3 (OR: 1.31, 95% CI 1.19-1.45). Other IR-related indexes (METS-IR, HOMA-IR, and TyG-BMI) showed fewer notable correlations with CKD. The association of IR-related indexes and the prevalence of CKD remained consistent in most subgroups (P for interactions > 0.05). TyG-WHtR was also the predictor of all-cause mortality in CKD patients (HR: 1.34, 95% CI 1.14-1.58), while other IR-related indexes were not correlated with the all-cause mortality or CVD mortality in CKD patients (P > 0.05). Otherwise, ROC curves showed that TyG-WHtR had more robust diagnostic efficacy than other IR-related indexes (METS-IR, HOMA-IR, TyG, and TyG-BMI) in predicting CKD (area under the curve: 0.630, 95% CI 0.615-0.644).

CONCLUSIONS

IR-related biomarkers (METS-IR, HOMA-IR, TyG, and TyG-BMI) were positively correlated with the prevalence of CKD. Moreover, TyG-WHtR enhanced CKD and its all-cause mortality prediction. In patients with elevated levels of IR-related indexes, the early detection and intervention of IR may reduce the occurrence of CKD and the prognosis of CKD patients.

Biomarkers of chronic kidney disease in older individuals: navigating complexity in diagnosis

Chronic kidney disease (CKD) in older individuals is a matter of growing concern in the field of public health across the globe. Indeed, prevalence of kidney function impairment increases with advancing age and is often exacerbated by age-induced modifications of kidney function, presence of chronic diseases such as diabetes, hypertension, and cardiovascular disorders, and increased burden related to frailty, cognitive impairment and sarcopenia. Accurate assessment of CKD in older individuals is crucial for timely intervention and management and relies heavily on biomarkers for disease diagnosis and monitoring. However, the interpretation of these biomarkers in older patients may be complex due to interplays between CKD, aging, chronic diseases and geriatric syndromes. Biomarkers such as serum creatinine, estimated glomerular filtration rate (eGFR), and albuminuria can be significantly altered by systemic inflammation, metabolic changes, and medication use commonly seen in this population. To overcome the limitations of traditional biomarkers, several innovative proteins have been investigated as potential, in this review we aimed at consolidating the existing data concerning the geriatric aspects of CKD, describing the challenges and considerations in using traditional and innovative biomarkers to assess CKD in older patients, highlighting the need for integration of the clinical context to improve biomarkers' accuracy.

[Nephroprotection: General principles and application to the patients with cancers - when nephroprotection is essential for oncological care plan]

Nephroprotection is a set of recommendations that aim to prevent the risks of acute and/or chronic renal failure and to limit the progression of renal failure towards an end stage. Nephroprotection is not limited to nephrology and applies to all patients at risk of renal failure. Cancer patients are particularly at risk of developing intrinsic and extrinsic renal failure, as well as the toxicity of specific treatments. However, they are poorly included in nephroprotection studies. Thus, current guidelines have not been adapted to these pathologies and oncology-specific comorbidities, such as malnutrition or prognosis, are often not taken into account. In this article, we review the established recommendations by transposing them to the cancer patient as a whole. In addition to the reminder of hygiene and dietary rules to control blood pressure and diabetes, we discuss the importance of therapeutic education, iatrogeny and treatment options to control renal failure in this context. The lack of clearly established data in cancer confirms the needs to strengthen links between oncologists, hematologists and nephrologists and reinforces the emergence of onco-nephrology as a new discipline.

Identifying the potential therapeutic effects of miR‑6516 on muscle disuse atrophy

Muscle atrophy is a debilitating condition with various causes; while aging is one of these causes, reduced engagement in routine muscle‑strengthening activities also markedly contributes to muscle loss. Although extensive research has been conducted on microRNAs (miRNAs/miRs) and their associations with muscle atrophy, the roles played by miRNA precursors remain underexplored. The present study detected the upregulation of the miR‑206 precursor in cell‑free (cf)RNA from the plasma of patients at risk of sarcopenia, and in cfRNAs from the muscles of mice subjected to muscle atrophy. Additionally, a decline in the levels of the miR‑6516 precursor was observed in mice with muscle atrophy. The administration of mimic‑miR‑6516 to mice immobilized due to injury inhibited muscle atrophy by targeting and inhibiting cyclin‑dependent kinase inhibitor 1b (Cdkn1b). Based on these results, the miR‑206 precursor appears to be a potential biomarker of muscle atrophy, whereas miR‑6516 shows promise as a therapeutic target to alleviate muscle deterioration in patients with muscle disuse and atrophy.

Relationships between sarcopenia, depressive symptoms, and the risk of cardiovascular disease in Chinese population

BACKGROUND

Previous studies had indicated that sarcopenia and depressive symptoms were associated with increased risk of cardiovascular disease (CVD). The aim of present study was to evaluate the combined effect of sarcopenia and depressive symptoms on the CVD risk.

METHODS

A total of 11,011 participants from the China Health and Retirement Longitudinal Study 2011-2020 were included. Multivariate Cox proportional hazards regression model was used to explore the associations between sarcopenia, depressive symptoms and new-onset CVD, stroke and cardiac events.

RESULTS

During the 7-year follow-up, a total of 2,388 respondents experienced CVD (including 812 stroke and 1,831 cardiac events). There is a significant additive and multiplicative interactions of sarcopenia and depressive symptoms on risk of CVD, stroke and cardiac events. Compared with those without sarcopenia and depressive symptoms, individuals with depressive sarcopenia had the highest risk of CVD, stroke and cardiac events, with the corresponding hazard ratios (95% confidence interval) were 1.43 (1.26-1.63), 1.45 (1.15-1.82) and 1.50 (1.29-1.74), respectively.

CONCLUSION

Our study indicated that there was a combined effect of sarcopenia and depressive symptoms on the risk of CVD, stroke and cardiac events. Our findings highlighted the importance of identifying sarcopenia and depressive symptoms, and intervening much earlier both in older and younger population.

Low handgrip strength is related to elevated echogenicity in patients with chronic kidney disease: A pilot, cross-sectional and exploratory study

OBJECTIVES

Evaluate associations between triceps braqui muscle ultrasound measures (TB US) and handgrip strength (HGS), and the sensibility of TB US for low HGS in non-dialysis-dependent chronic kidney disease (nd-CKD) patients.

PARTICIPANTS AND METHODS

This pilot, cross-sectional, and exploratory study evaluated TB cross-sectional images from A-mode US and processed by FIJI-Image J to obtain muscle thickness (MT), echogenicity (EI), cross-sectional area (CSA), pennation angle (PA), and fascicle length (Lf) associating them with absolute HGS by simple and, multiple linear regression. The HGS was normalized to body mass index (BMI) and separated into low HGS (HGS/BMI≤10p according to sex and age) and adequate HGS (HGS/BMI>10p) groups. The body composition was from multifrequency bioimpedance. ROC analysis verified the TB US diagnostic accuracy to low HGS.

RESULTS

Were included 42 (21M/21F) adults with 65.5 (60-70) y median age, 47.22% in 3b CKD stage. The low HGS group (45.23%) showed a higher fat mass (FM), TB muscle medium head's PA, and EI than adequate HGS (p<0.05). In crude model, a pixels increase in EI was associated with a 0.452kgf HGS reduction (p=0.019); adjusted for sex, age, and FM, a one-unit increase in EI was associated with a 0.510kgf HGS reduction (p=0.011). The EI also showed moderate diagnostic accuracy (AUC=0.730; CI 95%=0.589; 0.919) to low HGS and a sensitivity of 86.9% (cutoff≥13.52 pixels).

CONCLUSION

In nd-CKD patients, of all measurements from US, the EI was the most associated with HGS, and the only one sensitive to low HGS diagnosis.

Quantification of volumetric thigh and paravertebral muscle fat content: comparison of quantitative Dixon (Q-Dixon) magnetic resonance imaging (MRI) with high-speed T2-corrected multiecho MR spectroscopy

Background

Muscle fat infiltration (MFI) is increasingly recognized as a critical factor influencing muscle function and metabolic health. Accurate quantification of MFI is essential for diagnosing and monitoring various muscular and metabolic disorders. Quantitative Dixon (Q-Dixon) magnetic resonance imaging (MRI) and high-speed T2-corrected multi-echo (HISTO) magnetic resonance spectroscopy (MRS) are both advanced imaging techniques that offer potential for detailed assessment of MFI. However, the validity and reliability of these methods in measuring volumetric changes in muscle composition, particularly in both thigh and paravertebral muscles, have not been thoroughly compared. This study aims to validate volumetric measurements using Q-Dixon MRI against HISTO MRS in thigh and paravertebral muscles, taking into account the heterogeneity of MFI.

Methods

A retrospective study was conducted with 54 subjects [mean age, 60 years; 38 male (M)/16 female (F)] for thigh muscle and 56 subjects (mean age, 50 years; 22 M/34 F) for paravertebral muscle assessment using a 3-Tesla MRI. The proton density fat fraction (PDFF) was measured with Q-Dixon MRI and HISTO MRS within the upper-middle part of quadriceps femoris and paravertebral muscles at L4/5 level in volumes-of-interest (VOIs). The corresponding volumetric Q-Dixon freehand VOI PDFF was measured. Scatterplots, Bland-Altman plots, Spearman correlation coefficients, and Wilcoxon signed rank test with Bonferroni correction were employed. The Kruskal-Wallis H tests followed by Bonferroni-corrected post hoc tests were analyzed to compare parameter differences with visual MFI grades.

Results

Q-Dixon cubic VOI PDFF correlated positively with HISTO MRS PDFF in thigh (r=0.96, P<0.001) and paravertebral groups (r=0.98, P<0.001), with insignificant differences (P=0.29, 0.82, respectively). Both PDFF values from cubic VOIs in Q-Dixon and HISTO MRS differed from the freehand Q-Dixon PDFF (all P<0.001). Only for <5% HISTO MRS PDFF, there was a difference between HISTO MRS PDFF and Q-Dixon cubic VOI PDFF (P=0.002).

Conclusions

Volumetric Q-Dixon cubic VOI PDFF exhibited good correlation and consistency with HISTO MRS PDFF for quantitative fat assessment in thigh and paravertebral muscles except for muscles with fat fraction <5%, and the Q-Dixon freehand VOI PDFF offers a more comprehensive assessment of the actual MFI compared to cubic VOI.

Clinical usefulness of psoas muscle thickness for the prognosis of acute type A aortic dissection patients undergoing total arch replacement

Background

Sarcopenia has emerged as a comprehensive predictor of mortality in diseased populations. The aim of this study was to evaluate the prognostic and predictive value of psoas muscle thickness/height (PMTH) measurement in patients with acute type A aortic dissection (AAAD).

Methods

A retrospective analysis of patients (from January 2020 to December 2020) who underwent AAAD surgery at our institution was conducted. PMTH, as a measure of sarcopenia, was measured by preoperative computed tomography. Patients were classified into two groups according to the cut-off value of PMTH. To balance potential bias, a 1:1 propensity score matching (PSM) with a caliper 0.05 was conducted.

Results

PSM analysis created 68 pairs of patients. In short-term outcomes, a lower PMTH value was strongly correlated with higher in-hospital mortality and renal failure. Receiver operating characteristic (ROC) analysis suggested that sarcopenia had good predictive capabilities in in-hospital mortality, with the area under curve (AUC) of 0.81 [95% confidence interval (CI): 0.64-0.97]. During a median follow-up of 37 months, 24 (19.4%) patients died, including 16 in low PMTH group and 8 in high PMTH group. Kaplan-Meier analysis indicated the sarcopenia significantly affected long-term survival [log-rank P=0.02; hazard ratio (HR) 2.53 (95% CI: 1.13-5.66)]. Multivariable Cox regression analysis revealed that sarcopenia was an independent predictor for decreased survival [HR 2.73 (95% CI: 1.15-8.78)].

Conclusions

Sarcopenia defined from the PMTH may be a useful tool for predicting short- and long-term mortality in patients after AAAD surgery.

High-intensity interval training using electrical stimulation ameliorates muscle fatigue in chronic kidney disease-related cachexia by restoring mitochondrial respiratory dysfunction

Background

Exercise, especially high-intensity interval training (HIIT), can increase mitochondrial respiratory capacity and enhance muscular endurance, but its systemic burden makes it difficult to safely and continuously prescribe for patients with chronic kidney disease (CKD)-related cachexia who are in poor general condition. In this study, we examined whether HIIT using electrical stimulation (ES), which does not require whole-body exercise, improves muscle endurance in the skeletal muscle of 5/6 nephrectomized rats, a widely used animal model for CKD-related cachexia.

Methods

Male Wistar rats (10 weeks old) were randomly assigned to a group of sham-operated (Sham) rats and a group of 5/6 nephrectomy (Nx) rats. HIIT was performed on plantar flexor muscles in vivo with supramaximal ES every other day for 4 weeks to assess muscle endurance, myosin heavy-chain isoforms, and mitochondrial respiratory function in Nx rats. A single session was also performed to identify upstream signaling pathways altered by HIIT using ES.

Results

In the non-trained plantar flexor muscles from Nx rats, the muscle endurance was significantly lower than that in plantar flexor muscles from Sham rats. The proportion of myosin heavy chain IIa/x, mitochondrial content, mitochondrial respiratory capacity, and formation of mitochondrial respiratory supercomplexes in the plantaris muscle were also significantly decreased in the non-trained plantar flexor muscles from Nx rats than compared to those in plantar flexor muscles from Sham rats. Treatment with HIIT using ES for Nx rats significantly improved these molecular and functional changes to the same degrees as those in Sham rats. Furthermore, a single session of HIIT with ES significantly increased the phosphorylation levels of AMP-activated protein kinase (AMPK) and p38 mitogen-activated protein kinase (MAPK), pathways that are essential for mitochondrial activation signaling by exercise, in the plantar muscles of both Nx and Sham rats.

Conclusion

The findings suggest that HIIT using ES ameliorates muscle fatigue in Nx rats via restoration of mitochondrial respiratory dysfunction with activation of AMPK and p38 MAPK signaling. Our ES-based HIIT protocol can be performed without placing a burden on the whole body and be a promising intervention that is implemented even in conditions of reduced general performance status such as CKD-related cachexia.

Physical exercise as a modulator of the purinergic system in the control of sarcopenia in individuals with chronic kidney disease on hemodialysis

The word sarcopenia derives from the Greek terms "sarx" for meat and "penia" for loss, thus being used to define reductions in muscle mass, muscle strength, and lower physical performance that compromise, mainly, the elderly population. Its high negative impact on patients' quality of life encourages the production and publication of new studies that seek to find methods to prevent and reverse cases of loss of muscle mass and strength. Furthermore, the high prevalence of sarcopenia in patients with chronic kidney disease (CKD) is closely related to its pathophysiology, which consists of a state of increased protein catabolism and decreased muscle tissue synthesis. Also considering the inflammatory nature of CKD and sarcopenia, the purinergic system has been an important target of studies, which seek to relate it to the two previous conditions. This system achieves anti-inflammatory action by inhibiting, through adenosine, pro-inflammatory factors such as interleukin-12 (IL-12), tumor necrosis factor alpha (TNF-α), and nitric oxide (NO), as well as by releasing anti-inflammatory substances such as interleukin-10 (IL-10). Simultaneously, the purinergic system presents pro-inflammatory activity, signaled by adenosine triphosphate (ATP), which occurs through the activation of T cells and the release of pro-inflammatory factors such as those mentioned above. Therefore, the ability of this system to act on inflammatory processes can promote positive and negative changes in the clinical aspect of patients with CKD and/or sarcopenia. Furthermore, it appears that there is a correlation between the practice of repeated physical exercise with the clinical improvement and in the quality of life of these patients, presenting a decrease in the levels of C-reactive protein (CRP), NTPDase, and the pro-inflammatory cytokine IL-6, such as increases in IL-10 resulting from modulation of the purinergic system. In this way, the present article seeks to evaluate the effect of physical exercise as a modulator of the purinergic system in the control of sarcopenia in patients with CKD on hemodialysis, in order to trace a relationship that can bring benefits both for biological markers and for quality of life of these patients.

Sarcopenia and mild kidney dysfunction and risk of all-cause and cause-specific mortality in older adults

BACKGROUND

Sarcopenia has been identified as a risk factor for increased mortality in individuals with CKD. However, when considering individuals with mild kidney dysfunction prior to CKD, the impact of sarcopenia on adverse outcomes, particularly mortality, remains uncertain.

METHODS

This study included 323 801 participants from the UK Biobank. Mild kidney dysfunction was defined as estimated glomerular filtration rate between 60 and 89.9 mL/min/1.73 m2, and sarcopenia was defined according to the criteria of the 2019 European Working Group of Sarcopenia in Older People. Cox proportional hazard models with inverse probability weighting and competing risk models were used for analysis.

RESULTS

During a median follow-up of 11.8 years, 20 146 participants died from all causes. Compared with participants with normal kidney function and without sarcopenia, those with mild kidney dysfunction or sarcopenia had significantly increased risks of all-cause mortality [hazard ratio (HR) 1.16, 95% confidence interval (CI) 1.12-1.19; HR 1.29, 95% CI 1.20-1.37]; those with both mild kidney dysfunction and sarcopenia had an even higher risk of all-cause mortality (HR 1.61, 95% CI 1.52-1.71), with a significant overall additive interaction (relative risk due to interaction 0.17, 95% CI 0.05-0.29). Further subgroup analyses revealed that the associations of probable sarcopenia with all-cause and cause-specific mortality (non-accidental cause, non-communicable diseases and cancer) were stronger among participants with mild kidney dysfunction than those with normal kidney function.

CONCLUSIONS

The study indicates that sarcopenia and mild kidney dysfunction synergistically increase the risk of all-cause and cause-specific mortality. Early recognition and improvement of mild kidney function or sarcopenia in older people may reduce mortality risk but would require more prospective confirmation.