Sarcopenia and Physical Inactivity in Patients With Chronic Kidney Disease

Depression and Quality of Life in Patients With Chronic Kidney Disease: A Mediation Analysis of Handgrip Strength and Demoralization

BACKGROUND

Chronic kidney disease (CKD) is a progressive disease impacting the physical function and mental health of sufferers. Depression is known to negatively impact quality of life, whereas handgrip strength and demoralization are important factors affecting physical and mental health. Lower handgrip strength has been associated with sarcopenia and higher risk of hospitalization in patients and higher workloads for nurse caregivers. Few studies have investigated the complex relations among these factors in patients with CKD.

PURPOSE

This study was designed to investigate the mediating effects of grip strength and demoralization on the relationship between depression and quality of life in patients with CKD.

METHODS

Two hundred fifty patients with CKD comprised the study sample. The hypotheses were tested using the PROCESS macro.

RESULTS

Depression was found to be negatively associated with handgrip strength and quality of life but positively associated with demoralization. The results indicate that both handgrip strength and demoralization mediate the association between depression and quality of life. Moreover, the results of multiple mediation model analysis showed handgrip strength and demoralization both play important roles in the link between depression and quality of life.

CONCLUSIONS

The results of this study indicate that handgrip strength and demoralization mediate the relationship between depression and quality of life in patients with CKD. Thus, increasing handgrip strength and decreasing demoralization levels may mitigate the impact of depression on quality of life. Therefore, nurses should better appreciate the importance of handgrip strength for patients with CKD and evaluate handgrip strength. Nurses should also develop physical and mental interventions to increase handgrip strength and decrease demoralization.

Physical activity and renal outcome in diabetic and non-diabetic patients with chronic kidney disease stage G3b to G5

The association of physical activity with renal outcome and mortality in advanced chronic kidney disease (CKD; i.e., estimated glomerular filtration rate [eGFR] < 45 ml/min/1.73m2) is poorly studied. We examined this association in patients with advanced CKD in Japan. We used the Rapid Assessment of Physical Activity to assess baseline physical activity and classify patients as active or inactive. CKD progression was defined as 40% decline in eGFR, eGFR < 10, or requiring dialysis or transplantation. Among the 1,808 eligible patients, after adjusting for possible confounders, hazard ratios (HRs) for poor renal outcome in the active group were 0.68 (95% CI, 0.44-1.04), 1.09 (0.86-1.38), and 1.01 (0.82-1.25) in CKD stage G3b, G4, and G5, respectively, suggesting a renal benefit of exercise in CKD stage G3b. Adjusted HRs for death were 0.79 (0.40-1.57), 0.55 (0.38-0.80), and 0.75 (0.44-1.26) in stage G3b, G4, and G5, respectively. While the adjusted HRs of death were 0.84 (0.52-1.38) and 0.60 (0.43-0.83) in diabetic and non-diabetic patients, suggesting that exercise may reduce mortality in non-diabetic patients. Our study suggests that exercise is associated with better survival in non-diabetic patients with CKD stage G3b-5, and better renal outcome in diabetic and non-diabetic CKD stage G3b.

Physical Activity in Patients With Chronic Kidney Disease: The Effects of Caregivers and Residential Factors

Introduction Physical inactivity is common in chronic kidney disease (CKD) patients; several patient- and disease-related factors are linked to a sedentary lifestyle, but social and environmental influences remain unexplored. This study evaluates the level of physical activity in patients with CKD and investigates the associations with caregivers' physical activity levels, characteristics of the residential environment, and objective measures of exercise capacity. Methods Eighty CKD patients (20 per CKD stage 2-4) were included; patients and their carers filled out the International Physical Activity Questionnaire (IPAQ), questionnaires about residential environment and past exercise habits. The CKD patients also performed a 30-sec sit-to-stand-test (30-STS) as a measure of exercise capacity. Results According to the IPAQ-score, CKD patients were largely inactive (only 10% reported health-enhancing activity levels); no differences were found between CKD stages. The 30-STS was also impaired, and the number of repetitions significantly decreased with advancing CKD stages (14.2±2.9 vs. 12.6±5.4 vs. 10.4±3.3 vs. 10.5±3.5; p=0.008). Carers were also highly inactive but still had higher physical activity compared to patients (moderate intensity metabolic equivalents (METS) p=0.03, vigorous intensity METS p=0.053); no correlation between carers' and patients' physical activity was noted (p=0.702). Patients' physical activity was associated with residential factors: living in a detached house compared to an apartment (p=0.013 for moderate intensity and p=0.017 for vigorous METS), having a garden (p=0.019 for moderate intensity and p=0.022 for vigorous METS) and accessing house by stairs (p=0.037 for vigorous METS), were associated with higher physical activity. Conclusions Physical activity was significantly reduced in CKD patients, irrespectively disease stage. Carers were also highly inactive, but no association was found between the patients' and carers' daily activities. Residential characteristics were the only factors found to be associated to patients' physical activity levels. Personalized, supportive interventions are required, taking into account the patients' social support and microenvironment, in order to increase the physical activity level in this population.

Fasting Glycemia, Glycosylated Hemoglobin and Malnutrition Inflammation Are Associated With Sarcopenia in Older People With Chronic Kidney Disease Undergoing Hemodialysis Treatment: A Cross-Sectional Study

BACKGROUND

Contradictory data are available on the possible association between sarcopenia and other clinical disorders in patients with chronic kidney disease (CKD) undergoing hemodialysis.

OBJECTIVE

To determine the association between sarcopenia and markers associated with systemic inflammation, fasting glycemia, and quality of life in older people with CKD undergoing hemodialysis.

METHODS

This was an analytical cross-sectional study. People over 60 years with stage 5 CKD undergoing hemodialysis were invited to participate. Sarcopenia was assessed using the criteria of the European Working Group on Sarcopenia in Older People. Clinical variables such as body mass index, comorbidities, malnutrition inflammation, quality of life, fasting glycemia, glycosylated hemoglobin, hematocrit, uremia, creatinine, sodium, calcium, potassium, albumin, ferritin, C reactive protein were measured.

RESULTS

Twenty-three patients with CKD were included. The prevalence of sarcopenia was 56.5%. Sarcopenic participants showed higher fasting glycemia, glycosylated hemoglobin, and malnutrition inflammation, as well as expected lower physical performance compared to nonsarcopenic participants. Correlations that ranged from moderate to strong were observed between sarcopenia and clinical characteristics such as fasting glycemia (r=0.48; P<0.05), glycosylated hemoglobin (r=0.44; P<0.05), malnutrition inflammation (r=0.46; P<0.05), skeletal muscle mass (r=-0.70; P<0.01), and balance capacity (r=-0.66; P<0.01). Regression analyses showed that fasting glycemia increased the risk of sarcopenia by 1.82 times (OR=1.82; P=0.04).

CONCLUSIONS

In a sample of older people with CKD who underwent hemodialysis, sarcopenia was correlated with fasting glycemia, glycosylated hemoglobin, and malnutrition inflammation. However, only fasting glycemia was found to be a significant predictor of sarcopenia. More studies are needed to determine the influence of glycemic control on sarcopenia in older people with CKD.

Inflammation and aging-related disease: A transdisciplinary inflammaging framework

Inflammaging, a state of chronic, progressive low-grade inflammation during aging, is associated with several adverse clinical outcomes, including frailty, disability, and death. Chronic inflammation is a hallmark of aging and is linked to the pathogenesis of many aging-related diseases. Anti-inflammatory therapies are also increasingly being studied as potential anti-aging treatments, and clinical trials have shown benefits in selected aging-related diseases. Despite promising advances, significant gaps remain in defining, measuring, treating, and integrating inflammaging into clinical geroscience research. The Clin-STAR Inflammation Research Interest Group was formed by a group of transdisciplinary clinician-scientists with the goal of advancing inflammaging-related clinical research and improving patient-centered care for older adults. Here, we integrate insights from nine medical subspecialties to illustrate the widespread impact of inflammaging on diseases linked to aging, highlighting the extensive opportunities for targeted interventions. We then propose a transdisciplinary approach to enhance understanding and treatment of inflammaging that aims to improve comprehensive care for our aging patients.

Physical activity and exercise in chronic kidney disease: consensus statements from the Physical Exercise Working Group of the Italian Society of Nephrology

The Italian Society of Nephrology has tasked its Working Group on Physical Exercise with developing a consensus statement document on physical activity and exercise in patients with chronic kidney disease (CKD). This paper consists of 16 points that were discussed, and approved using the mini-Delphi method by 15 members of the working group. Each statement is based on a comprehensive review of the literature, clinical experience, and expert opinions. Overall, the statements affirm that regular physical activity and exercise training offer numerous benefits to CKD patients, including improved physical function, enhanced cardiometabolic and neuromuscular function, cognitive benefits, and an overall improvement in quality of life. Furthermore, exercise may provide nephroprotection and reduce mortality. These advantages are observed across all CKD stages, whether on conservative therapy or kidney replacement therapy (hemodialysis or peritoneal dialysis), and in kidney transplant recipients. Moreover, when physical activity and exercise training are implemented with appropriate precautions, they are safe in CKD patients. Gradual physical activity and customized exercise programs should be tailored to the patient's exercise tolerance, potentially enhancing compliance. Clinicians are encouraged to use a series of questionnaires and tests to assess the patient's level of physical activity and performance. However, exercise and physical activity are poorly implemented in clinical practice due to many barriers related to patients and healthcare staff. Overcoming these barriers requires the proactive role of the nephrologists, who should actively incorporate exercise training and promote physical activity within routine care plans. Adopting a multidisciplinary team approach, which includes nephrologists, nurses, exercise professionals, and dietitians, is crucial for providing comprehensive rehabilitation for CKD patients. Integrating new technologies and remote check ups could further enhance the effectiveness of these interventions.

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.

Comorbidity of patients with noncommunicable diseases in general practice. Eurasian guidelines

Создание руководства поддержано Советом по терапевтическим наукам отделения клинической медицины Российской академии наук.

The Moderating Role of Health Variables on the Association between Physical Exercise and Quality of Life in Patients with End-Stage Renal Disease

Scientific evidence demonstrates the positive impact that physical exercise has on the quality of life (QOL) of patients with chronic kidney disease (CKD). However, no study has proposed a model investigating the effect physical exercise has on the QOL of end-stage renal disease (ESRD) patients, considering the most frequent associated diseases (diabetes/hypertension). The objectives were (1) to explore the relationship between physical exercise and the QOL of adults with ESRD, and (2) to examine the moderating and/or mediating role of relevant patient variables. This non-interventional study utilized an ex post facto retrospective data analysis design with a sample of 310 patients with ESRD through two validated questionnaires. The dependent variables were the QOL scale (KDQOL-SF), and the physical function dimension (EFFISICA). The independent variables were the regular practice of intense physical activity (DEPINTE) and the daily time (in hours) the patient is in a sedentary attitude (TiParado). The moderating variables were the clinical situation and associated diseases. The mediator variable used was the body mass index. Bivariate and multiple regression analyses were conducted. Findings suggest implementing intense physical activity in transplant recipients and programmes to avoid sedentary lifestyles in dialysis patients have a positive effect in the QOL of ESRD patients.

Risk of sarcopenia, fear of COVID-19, anxiety, depression and physical activity levels: Associations across patients on hemodialysis within Greece

Objectives

The purpose of this multicenter cross-sectional study was to investigate the association between SARC-F, fear of COVID 19, anxiety, depression and physical activity in patients undergoing hemodialysis.

Methods

This study was conducted in 3 hemodialysis centers in Greece during the period of the COVID-19 pandemic. Sarcopenia risk was assessed using the Greek version of SARC-F (≥4). Demographic and medical history were collected from the patient's medical charts. The participants were also asked to fill the Fear of COVID-19 Scale (FCV-19S), the Hospital Anxiety and Depression Scale (HADS), and the International Physical Activity Questionnaire (IPAQ) questionnaire.

Results

A hundred and thirty-two (132) patients on hemodialysis (92 men, 70.75±13.14 years) were enrolled. Sarcopenia risk (utilizing the SARC-F) was found in 41.7% of patients on hemodialysis. The average duration of hemodialysis was 3.94±4.58 years. The mean score values for SARC-F, FCV-19S and HADS were 3.9±2.57, 21.08±5.32, and 15.02±6.69, respectively. The majority of patients were physically inactive. The SARC-F scores were strongly associated with age (r=56; p<0.001), HADS (r=0.55; p<0.001), levels of physical activity (r=0.5; p<0.001), but not with FCV-19S (r=0.27; p<0.001).

Conclusion

A statistically significant relationship was recorded between sarcopenia risk and age, anxiety/depression and levels of physical inactivity in patients on hemodialysis. Future studies are necessary in order to evaluate the association of specific characteristics of patients.

Could sarcopenia-related mortality in end-stage renal disease be underpinned by the number of hospitalizations and cardiovascular diseases?

PURPOSE

To investigate the association between sarcopenia with the number of all-cause mortality, hospitalizations, and cardiovascular diseases in patients with end-stage renal disease (ESRD).

METHODS

247 patients with ESRD (women, n = 97) (66.6 ± 3.53 years) participated in this study. At baseline, all participants were measured with dual-energy X-ray absorptiometry and handgrip dynamometer and were prospectively followed up for 5 years. The European Working Group on Sarcopenia in Older People guidelines were utilized for Sarcopenia determination. Cox proportional hazard analysis adjusted for established risk factors was used to quantify the risk between Sarcopenia and all-cause mortality.

RESULTS

Sixty-five participants (26%) were determined to have Sarcopenia at baseline and 38 (15%) have died during the follow-up. At baseline, Participants with Sarcopenia had lower body mass index and fat-free mass index. Moreover, through the 5-year follow-up, sarcopenic patients had higher number of cardiovascular disease (56.9% vs. 12.6%) and hospitalizations (93.8% vs. 49.5%) (all P < 0.0001). Sarcopenia was associated with significantly higher risk of mortality, [Hazard ratio = 3.3, (95% CI: 1.6-6.9), P = 0.001].

CONCLUSION

Sarcopenia may be a risk factor for hospitalizations, cardiovascular diseases, and all-cause mortality in patients with ESRD. These results provide support of the relevance in assessing sarcopenia in the clinical practice of chronic kidney disease and how muscle mass and strength may negatively impact the daily life of ESRD patients undergoing hemodialysis. Greater efforts at preventing muscle wasting and malfunctioning are needed through the worldwide healthcare system.

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.

The optimal exercise modality and intensity for hemodialysis patients incorporating Bayesian network meta-analysis and systematic review

Background: Physical inactivity is highly prevalent in patients with hemodialysis, and a large body of evidence reported the positive effect of different exercise modalities on their health outcomes. However, the effective dosage of exercise for hemodialysis patients still requires verification.

Objective: We aimed to determine the most effective exercise intensity and modality for improvements in physical function, blood pressure control, dialysis adequacy, and health-related quality of life for hemodialysis patients.

Design: Systematic review with network meta-analysis of randomized trials.

Data sources: Five electronic databases (PubMed, EMBASE, Web of Science, Cochrane CENTRAL, and Scopus) were searched for randomized controlled trials. Data extraction and quality appraisal were conducted by two authors independently. Data were analyzed by the R (version.3.6.2) and the Stata (version.15.0).

Result: We included 1893 patients involving four exercise modalities and six exercise intensities. Combined training (aerobic exercise plus resistance exercise) has been the top-ranking exercise modality for improving the 6-min walk test (6MWT) (surface under the cumulative ranking curve analysis (SUCRA) score, 90.63), systolic blood pressure control (SUCRA score, 77.35), and diastolic pressure control (SUCRA score, 90.56). Moreover, the top-ranking exercise intensity was moderate–vigorous for 6MWT (SUCRA score, 82.36), systolic blood pressure (SUCRA score, 77.43), and diastolic blood pressure (SUCRA score, 83.75). Regarding dialysis adequacy and health-related quality of life, we found no exercise modality or intensity superior to the placebo.

Conclusion: This network meta-analysis indicated that combined training and moderate–vigorous intensity might be the most effective interventions to improve 6MWT and blood pressure control. This finding helps further guide clinical exercise prescriptions for hemodialysis patients.

Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021268535].

Determinants of active energy expenditure in haemodialysis patients

BACKGROUND

Less active haemodialysis patients have an increased risk of mortality. We wished to determine which factors were associated with active energy expenditure (AEE), METHODS: We used the validated recent physical activity questionnaire to determine AEE, and estimated dietary protein intake and creatinine generation rates. We measured extracellular and total body water ratio (ECW/TBW) and appendicular lean muscle with bioimpedance, and arm strength by hand grip strength (HGS). Patients were graded using the Charlson co-morbidity, and the Clinical Frailty Score (CFS).

RESULTS

AEE was calculated in 98 patients (64 male), mean age 62.1±15.5 years, and AEE was negatively associated with CFS (r=-0.48), ECW/TBW (r=-0.47), and age (r=-0.4), all p<0.001, Charlson co-morbidity score (-0.27, p=0.007), and positively with serum creatinine (r=0.38, p<0.010), and HGS (r=0.25, p=0.016). Although protein nitrogen accumulation and creatinine generation were associated with resting energy expenditure (r=0.7 and r=0.44 respectively, both p<.0001), neither were associated with AEE. On multivariable analysis only CFS remained independently associated with AEE (β-0.031, 95% limits -0.057 to -0.004, p=0.024), although both age (negative p=0.07), and ALM (positive p=0.081) were retained in the model.

CONCLUSIONS

We found that AEE was lower with increasing frailty, age, loss of cell mass, co-morbidity and inflammation, and greater AEE in patients with higher serum creatinine and albumin, and greater muscle strength on univariate analysis, but only frailty remained independently associated on multivariable analysis. Whether exercise programmes designed to increase AEE in haemodialysis patients can improve frailty scores, and so reduce mortality risk reman to be determined. This article is protected by copyright. All rights reserved.

Renal dysfunction independently predicts muscle mass loss in patients following liver transplantation

BACKGROUND: Liver transplantation (LT) is the only curative treatment for cirrhosis. However, the presence of complications can impact outcomes following LT. Sarcopenia, or muscle mass loss, is highly prevalent in patients with cirrhosis and is associated with longer hospitalization stays and a higher infection rate post-surgery. We aimed to identify patients at higher risk of early sarcopenia post-LT. METHODS: This retrospective study included 79 cirrhotic patients who underwent LT. Muscle mass was evaluated using the third lumbar spine vertebra skeletal muscle mass index (SMI) and sarcopenia was defined using established cut-off values. Computerized tomography (CT) scans performed within six-month peri-operative period (three months pre- and post-LT) were included in the study. Complications and comorbidities were collected and correlated to SMI post-LT and predictive models for SMI post-LT were constructed. RESULTS: The overall prevalence of sarcopenia was 46% and 62% before and after LT, respectively. Newly developed sarcopenia was found in 42% of patients. Post-LT sarcopenia was associated with longer hospital stays (54±37 vs 29±10 days, p = 0.002), higher number of infection (3±1 vs 1±2, p = 0.027), and greater number of complications (5±2 vs 3±2, p <0.001) compared to absence of sarcopenia. Multivariate analyses showed that the SMI post-LT was independently associated with pre-LT renal function markers, the glomerular filtration rate (GFR) and creatinine (Model 1, GFR: β = 0.33; 95% CI = 0.04–0.17; p = 0.003; Model 2, Creatinine: β = –0.29; 95% CI = –0.10 to –0.02; p = 0.009). CONCLUSIONS: The present study highlights the potential role of renal dysfunction in the development and persistence of sarcopenia after LT.

Whey Protein, L-Leucine and Vitamin D Supplementation for Preserving Lean Mass during a Low-Calorie Diet in Sarcopenic Obese Women

In sarcopenic obese subjects it is essential to reduce body weight and preserve lean mass, in order to avoid a worsening of muscle function. Several studies have shown that leucine supplementation can be useful to improve skeletal muscle mass in sarcopenic patients. The aim of our study was to evaluate the effectiveness of a short-term low-calorie diet (LCD) combined with supplementation with whey protein and leucine on weight loss, lean mass and muscle strength in sarcopenic, obese, hyperinsulinemic and post-menopausal women. Sixteen females with a mean age of 60 years (range: 50–70 years), BMI 37.6 kg/m² (range: 31.7–44.1 Kg/m²), HOMA-index ≥ 2.5 (range: 2.9–12) were assigned to an LCD regimen (1000 kcal/day) with supplementation of 18 g whey proteins which 4.1 g of leucine for 45 days. Anthropometric indexes, blood and urine chemistry, body composition by DEXA, muscle strength by handgrip test and Short Physical Performance Battery (SPPB) were assessed at baseline and at the end of the treatment. A significant reduction in BMI (37.6 vs. 35.7 Kg/m²), waist circumference (107 vs. 102.4 cm), HOMA index (4.8 vs. 2.3) and fasting insulin (17.4 vs. 10.4 μIU/mL) was observed in all patients. Women preserved total lean body mass (55 vs. 5%) and significantly improved their muscle strength, as measured by handgrip (15.3 vs. 20.1 Kg), and their muscle function, as measured by SPPB (7.5 vs. 8.9). A significant increase in BUN was also observed (36.1 vs. 46.3). We conclude that LCD with adequate protein intake and supplementation with whey protein and leucine should be promoted to maintain muscle mass and improve muscle strength in post-menopausal women with sarcopenic obesity.

Functional Status and Engagement in Physical Activity Among Maintenance Dialysis Patients: A Mixed Methods Study

Rationale & Objective

People receiving maintenance hemodialysis (HD) experience significant activity barriers but desire the ability to do more and remain independent. To learn about how to help people who require dialysis stay active, a mixed methods study was designed to assess functional status and explore participants’ lived activity experiences.

Study Design

A concurrent mixed methods design was chosen to increase understanding of the real-life activity experiences of people who require dialysis through in-depth interviews paired with functional status measures. The qualitative findings were fully integrated with the quantitative results to link characteristics associated with different physical activity levels.

Setting & Participants

A purposive sample of 15 adult patients receiving maintenance HD for at least 3 months was recruited from 7 dialysis centers in Newark, New Jersey.

Analytical Approach

Thematic analysis using principles of interpretive phenomenology. Fully integrated quantitative and qualitative data with joint displays and conversion mixed methods.

Results

Participants had a median age of 58 years and were predominantly African American (83%) and men (67%). Three descriptive categories were generated about the participants. They described physical activity as a routine daily activity rather than structured exercise. All participants experienced substantial hardship in addition to chronic kidney disease and expressed that family, friends, and faith were essential to their ability to be active. An overarching theme was generated for participants’ mindsets about physical activity. Within the mindset theme, we discerned 3 subthemes comprising characteristics of participants’ mindsets by levels of engagement in physical activity.

Limitations

While code saturation and trends in functional status measures were achieved with 15 participants, a larger sample size would allow for deeper meaning saturation and statistical inference.

Conclusions

Patients receiving maintenance HD with an engaged mindset exhibited more adaptive coping skills, moved more, wanted to help others, and had a normal body weight habitus. These participants employed adaptive coping skills to carry out daily life activities of importance, highlighting the value of adaptive coping to help overcome the challenges of being physically active.

VLCKD in Combination with Physical Exercise Preserves Skeletal Muscle Mass in Sarcopenic Obesity after Severe COVID-19 Disease: A Case Report

The prevalence of sarcopenic obesity is increasing worldwide, with a strong impact on public health and the national health care system. Sarcopenic obesity consists of fat depot expansion and associated systemic low-grade inflammation, exacerbating the decline in skeletal muscle mass and strength. Dietary approach and physical exercise represent essential tools for reducing body weight and preserving muscle mass and function in subjects with sarcopenic obesity. This case report describes the effects of a dietary intervention, based on a Very-Low-Calorie Ketogenic Diet (VLCKD) combined with physical exercise, on body composition, cardiometabolic risk factors, and muscle strength in a woman with sarcopenic obesity, two weeks after hospitalization for bilateral interstitial pneumonia due to COVID-19. To our knowledge, this is the first case report to describe the efficacy of a combined approach intervention including VLCKD along with physical exercise, in reducing fat mass, improving metabolic profile, and preserving skeletal muscle performance in a patient with obesity, soon after severe COVID-19 disease.

Height-adjusted lean body mass and its associations with physical activity and kidney function in pediatric kidney transplantation

BACKGROUND

Although LBM is positively associated with health outcomes, studies assessing determinants for the accrual of ht-LBM, such as physical activity, are limited. This study aimed to assess ht-LBM levels in pediatric kidney transplant recipients and test its association with baseline and contemporaneous variables, including physical activity.

METHODS

A retrospective cross-sectional review was performed on 46 pediatric kidney transplant recipients, and a longitudinal review was performed on a subset of recipients with serial post-transplant (n = 21) and pre/post-transplant (n = 11) ht-LBM measurements. Ht-LBM measurements were obtained using DXA scans.

RESULTS

This cohort was 16.0 (IQR 12.3, 17.7) years old, 56.5% male and 46 ± 45 months post-transplant with a mean ht-LBM of 15.1 ± 2.5 kg/m² . A median ht-LBM increase of 1.6 kg/m² (IQR - 0.1, 2.6 kg/m² ; p < .01) was observed, over 29.2 ± 12.0 months from the earliest post-transplant scan obtained at 46 ± 25 months post-transplant until the most recent post-transplant scan. A 1.7 ± 1.4 kg/m² (p < .01) increase was observed between pre- and post-transplant DXA scans which were taken at 12 ± 11 months pre-transplant and 13 ± 6 months post-transplant, respectively. In separate adjusted models, lower physical activity questionnaire scores (n = 17, beta = 1.55, p = .02), faster rate of estimated glomerular filtration rate decline (beta = 0.05, p < .048) adjusted for annualized change in BSA, and younger age at scan (beta = 0.32, p < .01) were each significant predictors of lower ht-LBM.

CONCLUSIONS

Physical activity and kidney function may influence ht-LBM in the pediatric kidney transplant population.

Prevalence and determinants of sarcopenia in Indian patients with chronic kidney disease stage 3 & 4

Objectives

There is limited literature on the prevalence and determinants of sarcopenia in the Indian predialysis chronic kidney disease (CKD) population. The current study attempts to characterize sarcopenia in CKD stages 3 & 4 using 3-compartment model dual-energy X-ray absorptiometry (DXA).

Methods

This is secondary data from a randomized trial on bicarbonate supplementation for preserving muscle mass. A 3-compartment DXA was done to assess body composition in 188 subjects aged 18 to 65, with stable kidney function. Sarcopenia was defined by Asian Working Group criteria - appendicular skeletal mass index < 5.4 kg/m² in women and < 7 kg/m² in men.

Results

Sarcopenia was present in 69.1% (n = 130). There was no difference in the prevalence of sarcopenia in CKD stage 3 (n = 62; 72.1%) vs CKD stage 4 (n = 68, 66.7%); P = 0.434. A lower body mass index (BMI) (OR 1.69; 95% CI 1.43, 2.01) and lower bicarbonate levels (OR 1.22; 95% CI 1.02, 1.47), and age (OR 0.95; 95% CI 0.91, 0.98) was independently associated with the muscle mass. A BMI cut-off of 18 failed to identify sarcopenia in 78.4% (n = 102) subjects (Kappa statistic 0.396). The receiver operating characteristic curve for mid-arm muscle circumference for identifying sarcopenia was 0.651 (95% CI 0.561, 0.740).

Conclusions

Sarcopenia is highly prevalent in CKD 3 and 4. Sarcopenic individuals are older, with a low BMI and lower bicarbonate levels. The anthropometric parameters and biochemical parameters did not help identify sarcopenia in the predialysis population.

Klotho: An Emerging Factor With Ergogenic Potential

Sarcopenia and impaired cardiorespiratory fitness are commonly observed in older individuals and patients with chronic kidney disease (CKD). Declines in skeletal muscle function and aerobic capacity can progress into impaired physical function and inability to perform activities of daily living. Physical function is highly associated with important clinical outcomes such as hospitalization, functional independence, quality of life, and mortality. While lifestyle modifications such as exercise and dietary interventions have been shown to prevent and reverse declines in physical function, the utility of these treatment strategies is limited by poor widespread adoption and adherence due to a wide variety of both perceived and actual barriers to exercise. Therefore, identifying novel treatment targets to manage physical function decline is critically important. Klotho, a remarkable protein with powerful anti-aging properties has recently been investigated for its role in musculoskeletal health and physical function. Klotho is involved in several key processes that regulate skeletal muscle function, such as muscle regeneration, mitochondrial biogenesis, endothelial function, oxidative stress, and inflammation. This is particularly important for older adults and patients with CKD, which are known states of Klotho deficiency. Emerging data support the existence of Klotho-related benefits to exercise and for potential Klotho-based therapeutic interventions for the treatment of sarcopenia and its progression to physical disability. However, significant gaps in our understanding of Klotho must first be overcome before we can consider its potential ergogenic benefits. These advances will be critical to establish the optimal approach to future Klotho-based interventional trials and to determine if Klotho can regulate physical dysfunction.

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

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

Ursolic acid improves the indoxyl sulfate-induced impairment of mitochondrial biogenesis in C2C12 cells

BACKGROUND/OBJECTIVES

Patients with chronic kidney disease (CKD) have a high concentration of uremic toxins in their blood and often experience muscle atrophy. Indoxyl sulfate (IS) is a uremic toxin produced by tryptophan metabolism. Although an elevated IS level may induce muscle dysfunction, the effect of IS on physiological concentration has not been elucidated. Additionally, the effects of ursolic acid (UA) on muscle hypertrophy have been reported in healthy models; however, it is unclear whether UA ameliorates muscle dysfunction associated with chronic diseases, such as CKD. Thus, this study aimed to investigate whether UA can improve the IS-induced impairment of mitochondrial biogenesis.

MATERIALS/METHODS

C2C12 cells were incubated with or without IS (0.1 mM) and UA (1 or 2 µM) to elucidate the physiological effect of UA on CKD-related mitochondrial dysfunction and its related mechanisms using real-time reverse transcription-polymerase chain reaction, western blotting and enzyme-linked immunosorbent assay.

RESULTS

IS suppressed the expression of differentiation marker genes without decreasing cell viability. IS decreased the mitochondrial DNA copy number and ATP levels by downregulating the genes pertaining to mitochondrial biogenesis (Ppargc1a, Nrf1, Tfam, Sirt1, and Mef2c), fusion (Mfn1 and Mfn2), oxidative phosphorylation (Cycs and Atp5b), and fatty acid oxidation (Pdk4, Acadm, Cpt1b, and Cd36). Furthermore, IS increased the intracellular mRNA and secretory protein levels of interleukin (IL)-6. Finally, UA ameliorated the IS-induced impairment in C2C12 cells.

CONCLUSIONS

Our results indicated that UA improves the IS-induced impairment of mitochondrial biogenesis by affecting differentiation, ATP levels, and IL-6 secretion in C2C12 cells. Therefore, UA could be a novel therapeutic agent for CKD-induced muscle dysfunction.

Sarcopenia diagnosis in patients receiving hemodialysis: Agreement among different consensuses

BACKGROUND

There are many consensuses to diagnose sarcopenia, and their agreement in patients receiving hemodialysis (HD) is not clear. We described the sarcopenia prevalence in patients receiving HD using different consensuses and analyzed their level of agreement.

METHODS

Sixty-seven patients (43 men, 55 ± 14.6 years) were evaluated for appendicular skeletal muscle mass using dual-energy x-ray absorptiometry and muscle strength using handgrip strength. Patients were classified according to different sarcopenia consensuses (European Working Group on Sarcopenia in Older People [EWGSOP], Revised EWGSOP [EWGSOP2], Foundation for the National Institutes of Health Project [FNIH], and Asian Working Group for Sarcopenia 2019 [AWGS2]). Kappa analysis identified the level of agreement.

RESULTS

The prevalence of sarcopenia ranged from 1.5% to 11.9% depending on the sarcopenia consensus. The agreement between the different consensuses ranged from poor to almost perfect. FNIH and EWGSOP showed the lowest agreement (κ = 0.20; 95% CI, -0.14 to 0.54; P < 0.05), whereas EWGSOP2 and AWGS2 had the largest κ = 0.90 (95% CI, 0.71 to 1.00; P < 0.001). When stratified by age (≥60 years), the sarcopenia prevalence was higher in the older group (27% vs 2%; P = 0.004). In addition, male participants seemed to be more prone to sarcopenia compared with female counterparts, but this difference was not statistically confirmed (16% vs 4%; P = 0.242).

CONCLUSION

The sarcopenia consensuses showed from poor to almost perfect agreement, which varied the sarcopenia prevalence rates in patients receiving HD. EWGSOP2 and AWGS2 showed the largest agreement.

Physical activity is associated with nutritional biomarkers in hemodialysis patients: A cross-sectional study

OBJECTIVE

To explore the association between physical activity levels and nutritional biomarkers in hemodialysis patients.

METHODS

Eighty-six patients responded to the short version of the International Physical Activity Questionnaire to estimate the metabolic equivalent of tasks (MET) per week. A MET-min per week <600 was considered as sedentary. The nutritional biomarkers (i.e., albumin, globulin, and albumin/globulin ratio) were collected.

RESULTS

Sixty-five patients (75.6%) were sedentary. Binary logistic regression showed that patients with low albumin levels had an 89% lower chance to be physically active (p = 0.037), but it was not significant in the adjusted analysis (p = 0.052). Albumin and albumin/globulin ratio levels were correlated with MET-min per week (r = 0.34 and 0.30; both p < 0.05). Additionally, lower median albumin and albumin/globulin ratio levels were found in the sedentary patients (p = 0.021 and p = 0.031), respectively.

CONCLUSION

The physical activity levels were associated with albumin and albumin/globulin ratio, surrogates of nutritional status in hemodialysis patients. These nutritional biomarkers were lower in sedentary patients.

Prevalence and Factors Associated with Sarcopenia in Patients on Maintenance Dialysis in Australia-A Single Centre, Cross-Sectional Study

Background: Sarcopenia is associated with significant morbidity and mortality in patients with chronic kidney disease. The prevalence of sarcopenia in the dialysis population varies from 4% to 63%. However, the prevalence and risk factors of sarcopenia in the Australian dialysis population remain uncertain. Aim: To study the prevalence of sarcopenia in patients on maintenance dialysis by using the European Working Group on Sarcopenia in Older People (EWGSOP) diagnostic criteria of sarcopenia and to identify associated risk factors. Methods: We evaluated adult patients on maintenance haemodialysis and peritoneal dialysis in this single-centre cross-sectional study in Australia. Patient’s clinical (age, gender, dialysis modality and diabetic status) and laboratory parameters (serum albumin, calcium, phosphate, 25-hydroxy-vitamin D and parathyroid hormone levels) were investigated. We employed bioimpedance spectroscopy, hand grip dynamometer and the timed up and go test (TUG) to evaluate muscle mass, strength and function, respectively. Results: We evaluated 39 dialysis patients with a median age of 69 years old. The prevalence of sarcopenia was 18%. Sarcopenia was associated with low serum albumin (p = 0.02) and low serum phosphate level (p = 0.04). Increasing age and female sex were potential risk factors for sarcopenia (p = 0.05 and 0.08, respectively). Low lean muscle mass, reduced hand grip strength and prolonged TUG were present in 23.1%, 41% and 40.5%, respectively, of the cohort. The hand grip test had good correlation with lean muscle evaluation and the TUG. Conclusions: Sarcopenia was prevalent in 18% of maintenance haemodialysis patients from an Australian single-centre cohort, with low serum albumin and phosphate as significant risk factors.

Association of sarcopenia with mortality and end-stage renal disease in those with chronic kidney disease: a UK Biobank study

BACKGROUND

Sarcopenia, a degenerative and generalized skeletal muscle disorder involving the loss of muscle function and mass, is an under-recognized problem in clinical practice, particularly in chronic kidney disease (CKD). We aimed to investigate the prevalence of sarcopenia in individuals with CKD, its risk factors, and its association with all-cause mortality and progression to end-stage renal disease (ESRD).

METHODS

UK Biobank participants were grouped according to the presence of CKD (defined as an estimated glomerular filtration rate <60 mL/min/1.73 m² ) and as having probable (low handgrip strength), confirmed (plus low muscle mass), and severe sarcopenia (plus poor physical performance) based on the 2019 European Working Group of Sarcopenia in Older People and Foundation for the National Institutes of Health criteria. Risk factors were explored using logistic regression analysis. Survival models were applied to estimate risk of mortality and ESRD.

RESULTS

A total of 428 320 participants, of which 8767 individuals with CKD (46% male, aged 62.8 (standard deviation 6.8) years, median estimated glomerular filtration rate 54.5 (interquartile range 49.0-57.7) mL/min/1.72 m² ) were included. Probable sarcopenia was present in 9.7% of individuals with CKD compared with 5.0% in those without (P < 0.001). Sarcopenia was associated with being older; inflammation; poorer renal function; and lower serum albumin, total testosterone, and haemoglobin. The largest risk factors for sarcopenia were having three or more comorbidities (odds ratio: 2.30; 95% confidence interval: 1.62 to 3.29; P < 0.001) and physical inactivity: participants in the highest quartile of weekly activity were 43% less likely to have sarcopenia compared to the lowest quartile (odds ratio: 0.57; 0.42 to 0.76; P < 0.001). Participants with CKD and sarcopenia had a 33% (7% to 66%; P = 0.011) higher hazard of mortality compared with individuals without. Sarcopenic CKD individuals had a 10 year survival probability of 0.85 (0.82 to 0.88) compared with 0.89 (0.88 to 0.30) in those without sarcopenia, an absolute difference of 4%. Those with sarcopenia were twice as likely to develop ESRD (hazard ratio: 1.98; 1.45 to 2.70; P < 0.001).

CONCLUSIONS

Participants with reduced kidney function are at an increased risk of premature mortality. The presence of sarcopenia increases the risk of mortality and ESRD. Appropriate measurement of sarcopenia should be used to identify at-risk individuals. Interventions such as physical activity should be encouraged to mitigate sarcopenia.

The renal patient seen by non-renal physicians: the kidney embedded in the 'milieu intérieur'

Chronic kidney disease is defined as a decrease in renal function or evidence of kidney injury for >3 months. This represents an oversimplification that may confuse physicians. Thus kidney function is equated to glomerular filtration rate, which represents one of multiple kidney functions. Some potentially more important renal functions are lost earlier, such as the production for the anti-ageing factor Klotho. Overall, these changes modify the emergent properties of the body, altering the relationships between different organs and systems, in a manner that is difficult to predict the response to interventions based on normal physiology concepts, as there is a novel steady state of interorgan relations. In this regard we now discuss the impact of CKD on heart failure; osteomuscular and joint pain and bone fragility and fractures; and osteosarcopaenia as seen by a cardiologist, a rheumatologist and a geriatrician.

Consensus on the standard terminology used in the nutrition care of adult patients with chronic kidney disease

This nutrition consensus document is the first to coordinate the efforts of three professional organizations - the Brazilian Association of Nutrition (Asbran), the Brazilian Society of Nephrology (SBN), and the Brazilian Society of Parenteral and Enteral Nutrition (Braspen/SBNPE) - to select terminology and international standardized tools used in nutrition care. Its purpose is to improve the training delivered to nutritionists working with adult patients with chronic kidney disease (CKD). Eleven questions were developed concerning patient screening, care, and nutrition outcome management. The recommendations set out in this document were developed based on international guidelines and papers published in electronic databases such as PubMed, EMBASE(tm), CINHAL, Web of Science, and Cochrane. From a list of internationally standardized terms, twenty nutritionists selected the ones they deemed relevant in clinical practice involving outpatients with CKD. The content validity index (CVI) was calculated with 80% agreement in the answers. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework was used to assess the strength of evidence and recommendations. A total of 107 terms related to Nutrition Assessment and Reassessment, 28 to Diagnosis, nine to Intervention, and 94 to Monitoring and Evaluation were selected. The list of selected terms and identified tools will be used in the development of training programs and the implementation of standardized nutrition terminology for nutritionists working with patients with chronic kidney disease in Brazil.

Home-based exercise and bone mineral density in peritoneal dialysis patients: a randomized pilot study

BACKGROUND

The prevalence of osteopenia and osteoporosis is higher in patients with chronic kidney disease than that in the general population. Although physical exercise prevents bone loss in hemodialysis (HD) patients, previous studies have not focused on peritoneal dialysis (PD) patients. Therefore, we aimed to evaluate the effects of home-based exercise on bone mineral density (BMD) in patients with PD.

METHODS

Stable outpatients undergoing PD were randomly assigned to the intervention group (n = 26; male, 20; median age, 66 years) or usual-care group (n = 27; male, 21; median age, 64 years). Patients in the intervention group performed home-based exercises (resistance exercise, stretching, and aerobic exercise such as walking) for 6 months, whereas those in the usual-care group performed stretching and their usual physical activity. Based on dual X-ray absorptiometry, the primary outcomes were the BMD data of the lumbar spine and proximal femoral neck. Secondary outcomes included physical function and physical activity. Pre- and post-intervention values were compared.

RESULTS

There was no significant within-group change in the BMD of the lumbar spine, femoral neck, and hip after 6 months of the exercise program. The intervention group had significantly improved 30-s chair-stand test, 6-min walk test, and physical activity results.

CONCLUSIONS

Home-based exercises in patients with PD did not improve BMD at any of the sites evaluated. Improvement in physical function and physical activity may reduce the risk of falls in patients with PD.

TRIAL REGISTRATION

UMIN Clinical Trials Registry, UMIN000041678 . Registered September 4, 2020; retrospectively registered.

Exercise intolerance in kidney diseases: physiological contributors and therapeutic strategies

Exertional fatigue, defined as the overwhelming and debilitating sense of sustained exhaustion that impacts the ability to perform activities of daily living, is highly prevalent in chronic kidney disease (CKD) and end-stage renal disease (ESRD). Subjective reports of exertional fatigue are paralleled by objective measurements of exercise intolerance throughout the spectrum of the disease. The prevalence of exercise intolerance is clinically noteworthy, as it leads to increased frailty, worsened quality of life, and an increased risk of mortality. The physiological underpinnings of exercise intolerance are multifaceted and still not fully understood. This review aims to provide a comprehensive outline of the potential physiological contributors, both central and peripheral, to kidney disease-related exercise intolerance and highlight current and prospective interventions to target this symptom. In this review, the CKD-related metabolic derangements, cardiac and pulmonary dysfunction, altered physiological responses to oxygen consumption, vascular derangements, and sarcopenia are discussed in the context of exercise intolerance. Lifestyle interventions to improve exertional fatigue, such as aerobic and resistance exercise training, are discussed, and the lack of dietary interventions to improve exercise tolerance is highlighted. Current and prospective pharmaceutical and nutraceutical strategies to improve exertional fatigue are also broached. An extensive understanding of the pathophysiological mechanisms of exercise intolerance will allow for the development of more targeted therapeutic approached to improve exertional fatigue and health-related quality of life in CKD and ESRD.

The Effect of Exercise on Nutritional Status and Body Composition in Hemodialysis: A Systematic Review

Chronic kidney disease (CKD) is associated with aggravating factors which can affect both body composition and nutritional status. The purpose of the present systematic review was to investigate the potential effects of any physical activity on body composition or nutritional status among patients with stage 5 CKD undergoing hemodialysis (HD). A literature search on PubMed, Scopus, Web of Science, Google Scholar, and Cochrane was conducted and 14 randomized clinical trials were included. Skeletal muscle index and mid-arm muscular circumference increased after resistance exercise, and the results on body mass index, % body fat, and lean body mass varied. Serum albumin and C-reactive protein, in most cases, showed a slight increase and decrease, respectively. An improvement was also observed in body strength and overall performance status. The results suggest that physical activity can be beneficial for both the body composition and nutritional status of patients undergoing HD and can help in the prevention of sarcopenia. However, further research is needed mainly in the field of nutritional status.

PhysIOpathology of NEuromuscular function rElated to fatigue in chronic Renal disease in the elderly (PIONEER): study protocol

BACKGROUND

Chronic Kidney Disease (CKD) is associated with reduced muscular strength resulting in profound fatigue. The physiopathology of these changes, their prevalence and evolution are still debated. Moreover, we have little data on elderly CKD patients. The present study protocol aims to 1) quantify the prevalence of low muscle strength (dynapenia) in a cohort of elderly patients with advanced CKD and to 2) characterize their force production coupled with electromyographic features and the symptoms of fatigue compared to a matched control group.

METHODS

This is a case-control, prospective, interventional study.

INCLUSION CRITERIA

age ≥ 60 years; CKD Stage 3b-5; clinical stability (i.e. no hospitalization and ≤ 25% in creatinine increase in the previous 3 months). Controls with normal kidney function will be matched in terms of age, gender and diabetes mellitus (requisite: estimated glomerular filtration rate ≥ 60 ml/min/1.73m² available in the last 6 months). Exclusion criteria for cases and controls: neuromuscular disease, life expectancy < 3 months. The handgrip strength protocol is an intermittent test consisting in 6 series of 9 repetitions of 3-s sub-maximum contractions at 40% of the maximum voluntary contraction (MVC) and 2 s of resting time between contractions. Each series is separated by one fast sub-maximum contraction and one MVC. Strength is assessed with a high-frequency handgrip dynamometer paired with surface electromyography. Symptoms of fatigue are assessed using MFI-20 and FACIT-F questionnaires. In order to reach a statistical power of 96%, we plan to enroll 110 subjects in each group.

DISCUSSION

The novelty of this study resides in the application of an already validated set of tests in a population in which this combination (dynamometer, electromyography and questionnaires) has not previously been explored. We expect a high prevalence of dynapenia and a higher fatigability in CKD patients. A positive correlation is expected between reported fatigue and fatigability. Better appreciation of the prevalence and the relationship between fatigability and a sensation of fatigue can help us target interventions in CKD patients to improve quality of life and survival.

TRIAL REGISTRATION

The study was approved by Ethical Committee EST III n°20.03.01 and was recorded as a Clinical Trial (NCT04330807) on April 2, 2020.

Musculoskeletal losses in patients with ankylosing spondylitis

Ankylosing spondylitis (AS) is one of the most common autoinflammatory diseases that lead to early disability and high premature mortality rates. Along with lower bone mineral density, patients with AS are characterized by muscle mass decrease, such as sarcopenia. Musculoskeletal losses due to chronic immune inflammation and limited physical functioning significantly worsen prognosis and result in an increased risk of falls and fractures in patients with AS.

The review considers the pathogenetic mechanisms of the relationship between AS and sarcopenia and the main approaches to treating degenerative changes in muscle tissue in patients with AS.

Intradialytic Resistance Training Improves Functional Capacity and Lean Mass Gain in Individuals on Hemodialysis: A Randomized Pilot Trial

OBJECTIVE

To compare the effects of high vs moderate loads of intradialytic resistance training (RT) on body composition, sarcopenia prevalence, functional capacity, inflammatory markers, and quality of life (QoL) in individuals on hemodialysis.

DESIGN

A pilot randomized clinical trial.

SETTING

Two hemodialysis centers.

PARTICIPANTS

Individuals on hemodialysis (N=80; 51% men, aged 30-75y) in treatment for at least 3 months, adequately dialyzed (Kt/V≥1.2, where K is dialyzer clearance in mL/min, t is time, and V is volume of water) with vascular access via arteriovenous fistula.

INTERVENTIONS

The 12 weeks of intradialytic RT was performed 3 times per week. The training groups were: high-load intradialytic group (HLG, 8-10 repetitions), moderate-load intradialytic group (MLG, 16-18 repetitions), and control group (CG, stretching exercise). The total training volume was equalized among training groups.

MAIN OUTCOME MEASURES

Lean leg mass was assessed by a dual-energy x-ray absorptiometry; functional capacity was assessed by Short Physical Performance Battery and Timed Up and Go test; and QoL was assessed by Kidney Disease QoL Instrument, inflammatory markers, and sarcopenia.

RESULTS

After the training period, the HLG increased lean leg mass compared with the CG. The HLG also displayed improvements in the pain and physical function domains. The skeletal muscle index and functional capacity increased in both RT protocols. The prevalence of sarcopenia was reduced 14.3% and 25% in the MLG and HLG, respectively, while there was an increase of 10% in the CG. No differences were observed in cytokines after intervention.

CONCLUSIONS

High-load intradialytic RT was associated with gains in lean leg mass and QoL while functional capacity, appendicular muscle mass, and sarcopenia status were improved regardless of the RT load.

Sarcopenia is Associated with Malnutrition but Not with Systemic Inflammation in Older Persons with Advanced CKD

Background: In patients with chronic kidney disease (CKD), sarcopenia can be determined by a wide spectrum of risk factors. We evaluated the association of sarcopenia with nutritional, behavioral and inflammatory patterns in older patients with advanced CKD. Methods: we cross-sectionally evaluated 113 patients with CKD stages 3b-5. Sarcopenia was defined according to the EWGSOP2 criteria. We assessed: anthropometry, bioelectrical impedance analysis, physical, and psychological performance. Nutritional status was assessed using the Malnutrition Inflammation Score (MIS) and by verifying the eventual presence Protein Energy Wasting syndrome (PEW). Systemic inflammation was assessed by dosing: CRP, IL6, TNFα, MCP1, IL10, IL17, fetuin, IL12. Results: 24% of patients were sarcopenic. Sarcopenic individuals had lower creatinine clearance (18 ± 11 vs. 23 ± 19 mL/min; p = 0.0087) as well as lower BMI (24.8 ± 3.0 vs. 28.4 ± 5.5 Kg/m²; p < 0.0001) and a lower FTI (11.6 ± 3.9 vs. 14.4 ± 5.1 kg/m², p = 0.023). Sarcopenic persons had higher prevalence of PEW (52 vs. 20%, p < 0.0001) and a tendency to have higher MIS (6.6 ± 6.5 vs. 4.5 ± 4.0, p = 0.09); however, they did not show any difference in systemic inflammation compared to non-sarcopenic individuals. Conclusions: CKD sarcopenic patients were more malnourished than non-sarcopenic ones, but the two groups did not show any difference in systemic inflammation.

Exercise interventions for improving objective physical function in patients with end-stage kidney disease on dialysis: a systematic review and meta-analysis

Patients with end-stage kidney disease on dialysis have increased mortality and reduced physical activity, contributing to impaired physical function. Although exercise programs have demonstrated a positive effect on physiological outcomes such as cardiovascular function and strength, there is a reduced focus on physical function. The aim of this review was to determine whether exercise programs improve objective measures of physical function indicative of activities of daily living for patients with end-stage kidney disease on dialysis. A systematic search of Medline, Embase, the Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature identified 27 randomized control trials. Only randomized control trials using an exercise intervention or significant muscular activation in the intervention, a usual care, nonexercising control group, and at least one objective measure of physical function were included. Participants were ≥18 yr of age, with end-stage kidney disease, undergoing hemo- or peritoneal dialysis. Systematic review of the literature and quality assessment of the included studies used the Cochrane Collaboration’s tool for assessing risk bias. A meta-analysis was completed for the 6-min walk test. Data from 27 studies with 1,156 participants showed that exercise, regardless of modality, generally increased 6-min walk test distance, sit-to-stand time or repetitions, and grip strength as well as step and stair climb times or repetitions, dynamic mobility, and short physical performance battery scores. From the evidence available, exercise, regardless of modality, improved objective measures of physical function for end-stage kidney disease patients undergoing dialysis. It is acknowledged that further well-designed randomized control trials are required.

Longitudinal progression trajectory of random urine creatinine as a novel predictor of ESRD among patients with CKD

BACKGROUND

The clinical importance of random urine creatinine concentration in CKD population remains undetermined. Earlier studies found that lower 24-h urine creatinine excretion was associated with the risk of ESRD and all-cause mortality among CKD patients.

METHODS

We modeled the longitudinal trajectories of serial random urine creatinine among 4689 CKD patients enrolled in a national registry-based pre-ESRD program between 2003 and 2015 at a tertiary medical center. Other biochemical parameters including kidney function and serum albumin were regularly evaluated. Primary study outcomes were ESRD requiring maintenance dialysis and all-cause mortality.

RESULTS

By group-based trajectory modeling, the urine creatinine trajectories were characterized into three patterns: (1) stable low; (2) medium; and (3) high-declining. The adjusted hazard ratio of incident ESRD and all-cause mortality increased by 6% (95% CI: 1-12%) and 9% (95% CI: 2-17%), respectively, for each 20 mg/dL reduction in baseline random urine creatinine concentration. Consistently, there was a significant inverse linear dose-response relationship between baseline random urine creatinine and incident ESRD, but not all-cause mortality. Compared to patients with "medium" and "high-declining" urine creatinine trajectories combined, the adjusted hazard ratio for incidental ESRD among patients with a "stable-low" trajectory who had serial random urine creatinine concentrations stably below 100 mg/dL was 1.46 (95% CI: 1.00-2.12) after considering the competing risk of death.

CONCLUSIONS

Random urine creatinine not only serves as a common urinary concentration corrector but has its own clinical significance in risk stratification and outcome prediction in patients with advanced CKD.

Wasting in Chronic Kidney Disease – a Complex Issue

Chronic kidney disease (CKD) has become a global health burden and is associated with increased morbidity and mortality. In particular, wasting is highly prevalent in later stages of the illness with muscle loss being a common problem. The aetiology and progression of this wasting is complex and multiple states have been identified linked to wasting in CKD. These include: ‘malnutrition’, ‘disease-related malnutrition’, ‘protein-energy wasting’, ‘cachexia’, ‘sarcopenia’, ‘frailty’ and ‘muscle wasting’. The purpose of this paper is to review these terms in the context of CKD. Common features include weight loss, loss of muscle mass and muscle function principally driven by CKD disease specific factors and inflammatory mediators. Disease-related malnutrition would appear to be a more appropriate term for CKD than malnutrition as it take in to consideration disease specific factors such as inflammation for example.  Frailty is commonly associated with age-related decline in physiological function. Development of novel screening tools measuring across multiple domains of nutritional status, muscle and physical function may be useful in CKD. Research into potential treatments are currently underway with focus on multi-modal therapies including nutrition, resistance training and anabolic drugs such as myostatin blockade and selective androgen receptor modulators. A better understanding of different states and terms may help guide assessment and treatment opportunities for patients.

Low lean tissue mass can be a predictor of one-year survival in hemodialysis patients

Purpose: Nutritional status has a significant impact on the outcomes in the dialysis population. The aim of this study was to evaluate the association between body composition and a one-year survival of hemodialysis patients.

Methods: Forty-eight patients with chronic kidney disease stage V treated with hemodialysis for more than three months were included. Body composition was assessed by bioimpedance spectroscopy (Body Composition Monitor, Fresenius Medical Care). Blood samples for serum creatinine, serum albumin, serum prealbumin, high sensitivity C-reactive protein (hsCRP), interleukin 6 (IL-6), insulin-like growth factor 1(IGF-1) concentrations were taken before the midweek dialysis session.

Results: Over the course of a one-year observation, seven patients died. We observed a significantly lower lean tissue index (LTI) (p = .013) and higher IL-6 (p = .032) and hsCRP levels (p = .011) among the patients who died. The remaining biochemical markers did not differ between these two groups. Kapplan–Meier analysis revealed a worse survival rate in patients with sarcopenia (lower than the 10th percentile for their age and gender) in comparison with those with normal LTI. However, it was not of statistical significance (p = .055). LTI inversely correlated with age and IL-6 and positively with IGF-1.

Conclusions: Sarcopenia defined as decreased LTI, is a relatively common condition among patients undergoing maintenance hemodialysis, it can also be associated with a lower one-year survival rate. Decreased lean tissue mass can be associated with old age, lower IGF-1 levels and higher IL-6 levels. Body composition assessment may provide prognostic data for hemodialysis patients.

Atividade física e a qualidade de vida de pacientes com doença renal crônica em hemodiálise

RESUMO O objetivo deste estudo foi avaliar o nível de atividade física (NAF) de pacientes com doença renal crônica (DRC) em hemodiálise (HD) e correlacionar estes níveis à qualidade de vida relacionada à saúde (QVRS). Trata-se de um estudo correlacional, transversal, e com abordagem quantitativa. Participaram da pesquisa 84 pacientes com diagnóstico de DRC. Utilizou-se o questionário internacional de atividade física para identificar o NAF e o questionário genérico de qualidade de vida (SF-36) para avaliar a QVRS. Foram realizadas análises estatísticas descritivas. Utilizou-se o teste Kolmogorov-Smirnov e verificou-se ausência de normalidade nos dados. O teste U de Mann Whitney foi utilizado para a comparação da QVRS entre grupos (ativos e insuficientemente ativos), bem como o coeficiente de correlação de Spearman para correlacionar o NAF e a QVRS. O nível de significância adotado foi de 5%. Na comparação de grupos, verificou-se que os pacientes ativos apresentaram melhor percepção de QVRS se comparados aos insuficientemente ativos. Ainda, a partir do coeficiente de correlação de Spearman, observou-se que o NAF está correlacionado com a QVRS, com estatísticas significantes em diversas dimensões do SF-36. Sendo assim, sugere-se que a prática regular de atividade física (AF) pode contribuir para uma melhor percepção de QVRS de pacientes em HD.

The prevalence of muscle wasting (sarcopenia) in peritoneal dialysis patients varies with ethnicity due to differences in muscle mass measured by bioimpedance

BACKGROUND/OBJECTIVES

Sarcopenia is associated with increased mortality. European and North American recommended screening for low muscle mass uses gender specific cut points, with no adjustment for ethnicity. We wished to determine whether the prevalence of sarcopenia was altered by ethnicity in peritoneal dialysis (PD) patients.

SUBJECTS/METHODS

We measured appendicular lean mass indexed to height (ALMI) in PD patients by segmental bioimpedance and determined sarcopenia using different cut off points for reduced muscle mass.

RESULTS

We measured ALMI in 434 PD patients, 55.1% males, mean age 55.3 ± 16.2 years, 32.3% diabetic, 54.1% white, 23.7% Asian, 19.1% black. ALMI was lower in Asian women, compared to white and black women (6.4 ± 1.1 vs. 6.6 ± 1.0 and 6.9 ± 1.4 kg/m²), and lower in Asian men (7.5 ± 1.3 vs. 8.5 ± 1.2 and 8.7 ± 1.3 kg/m²), p < 0.001. Depending on the ALM/ALMI cut point; the prevalence of sarcopenia was greater in Asian patients (25.6-41.2% using North American or European cut points) compared to white (12.3-18.7%) and black patients (3.8-15.7%), p < 0.001, but <11% when using Asian-specific cut points. The prevalence of sarcopenia obesity (BMI ≥ 30 kg/m²) was <3%, for all groups. There was no association with duration of PD, dialysis prescription, residual renal function or small solute clearances.

CONCLUSIONS

There is no universally agreed consensus definition for loss of muscle mass (sarcopenia) and current European and North American recommended cut points for screening are adjusted only for gender. As body composition differs also with age and ethnicity, then ideally cut points should be based on age, gender and ethnicity normative values.

Sarcopenia in patients with chronic kidney disease not yet on dialysis: Analysis of the prevalence and associated factors

INTRODUCTION

Sarcopenia is a chronic condition that is associated with aging and characterized by a reduction of muscle mass, strength, and function. Sarcopenia is prevalent in patients with chronic kidney disease (CKD) and associated with increased morbidity and mortality, as well as cardiovascular complications.

OBJECTIVES

To investigate the prevalence of sarcopenia in patients with CKD not yet on dialysis and its correlation with clinical and laboratory variables and inflammatory markers.

METHODS

A total of 100 patients of both sexes aged over 18 were evaluated. Sarcopenia was defined using the criteria of the European Working Group on Sarcopenia in Older People (EWGSOP) and of the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project. Sociodemographic and clinical data, activities of daily living, functional capacity, and physical activity were also evaluated. Inflammation was assessed by the serum levels of high-sensitivity C-reactive protein (hsCRP) and interleukin (IL) 4 and 6.

RESULTS

The prevalence of sarcopenia was 11.9% and 28.7% using the EWGSOP and FNIH criteria, respectively. Sarcopenia was more prevalent in the more advanced stages of CKD (34.5% in stages 2 and 3A; and 65.5% in stages 3B, 4, and 5) and associated with worse performance in activities of daily living (p = 0.049), lower walking speeds (p < 0.001), and higher body mass indexes (BMIs) (p = 0.001) in the non-adjusted model. In addition, patients with sarcopenia had lower functional capacity (p = 0.012) and higher prevalence of physical inactivity (p = 0.041) compared with patients without sarcopenia. After adjustment for confounding variables, sarcopenia was still significantly correlated with walking speed (p = 0.004) and BMI (p = 0.002). HsCRP levels were inversely correlated with appendicular lean mass adjusted for BMI (p = 0.007) and were also positively associated with BMI (p = 0.001). IL4 levels were positively correlated with walking speed (p = 0.007) and lean mass in the lower limbs (p = 0.022).

CONCLUSIONS

Sarcopenia is common in patients with CKD, particularly in the most advanced stages of the disease. We observed an association between the levels of inflammatory markers and peripheral lean body mass, physical performance, and BMI. This association between sarcopenia and modifiable factors highlights the importance of early diagnosis and the implementation of therapeutic measures to minimize adverse outcomes in patients with CKD not yet on dialysis.