Association of sarcopenia with phase angle and body mass index in kidney transplant recipients

Bioelectrical impedance analysis for measuring body composition and predicting low muscle mass in apparently healthy pediatric outpatients: a retrospective observational study

BACKGROUND

The bioelectrical impedance analysis-derived phase angle is a proposed indicator of sarcopenia in adults. This study assessed the body composition of pediatric outpatients without underlying medical conditions to evaluate the predictive value of the phase angle in identifying low muscle mass, a risk factor for pediatric sarcopenia.

METHODS

Analyses were performed separately for each sex among 480 pediatric outpatients aged 5-18 years. Body composition variables were compared between low and normal body mass index-for-age z-score (BMIz) groups, including correlation analysis between the phase angle and other variables. The receiver operating characteristic curves of the phase angle, body mass index, and fat-free mass index (FFMI) were compared to predict a severely low appendicular skeletal muscle mass index (ASMI), defined as an ASMI below - 1 or - 2 standard deviations based on sex- and ethnicity-specific reference curves derived from dual-energy X-ray absorptiometry.

RESULTS

The low BMIz group showed a greater prevalence of a low fat-mass percentage and severely low ASMI, accompanied by notable changes in fat mass, muscle mass, height-squared adjusted indices, body water, protein, visceral fat area, and the phase angle (P < 0.05) compared with the normal BMIz group. The phase angle exhibited moderate correlations (P < 0.001) with the FFMI and ASMI (positive) and the visceral fat area and the extracellular water/total body water (ECW/TBW) ratio (negative) but no or negligible correlation with fat mass, fat-mass percentage, the fat mass index, or minerals. The phase angle' area under the curve for predicting a severely low ASMI was 0.743-0.785 (sensitivity: 62.3-80.4%; specificity: 67.0-75.0%). The area under the curve of the FFMI was 0.853-0.931 (sensitivity: 78.4-92.9%; specificity: 79.6-87.1%).

CONCLUSIONS

Body composition can identify fat and muscle wasting in children with a normal BMIz. The phase angle moderately correlated with the FFMI, ASMI, visceral fat area, and ECW/TBW ratio. The phase angle is a reasonable, although not a surrogate, indicator of the sarcopenia risk in pediatric outpatients.

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.

The phase angle before transplantation can predict the status of low muscle mass after kidney transplantation

BACKGROUND

This study aimed to evaluate the association between phase angle, muscle strength, and muscle mass in patients undergoing kidney transplantation.

METHODS

Patients whose pre- and follow-up phase angles were measured after kidney transplantation were enrolled. Phase angle and body composition were measured using a multi-frequency bioimpedance analysis device before and at 7 and 14 days and 3, 6, and 12 months after transplantation. Muscle strength was evaluated using handgrip strength (HGS). Low HGS was defined as < 28 kg in males and < 18 kg in females. Low muscle mass was defined as an appendicular lean mass index of < 7.0 kg/m2 in males and < 5.7 kg/m2 in females.

RESULTS

Eighty-eight patients (mean age 52.3 ± 10.1 years) were analyzed. The mean phase angle of pre-transplantation was 5.0 ± 1.0°. Body fat percentage was significantly higher at 6 and 12 months after transplantation than pre-transplantation (P < 0.0001). Twelve months after kidney transplantation, the prevalence of low HGS decreased (pre-transplantation vs. 12 months post-transplantation: 28.4% vs. 17.0%), and the prevalence of low muscle mass (pre-transplantation vs. 12 months post-transplantation: 21.6% vs. 28.4%) increased. The pre-transplantation phase angle was significantly associated with low muscle mass at 12 months after kidney transplantation (odds ratio [OR]: 0.34; 95% confidence interval [CI]: 0.16-0.72; P = 0.005). The pre-transplantation phase angle was not significantly associated with low HGS (OR: 0.37; 95% CI 0.12-1.17; P = 0.090) 12 months after kidney transplantation.

CONCLUSIONS

Pre-transplantation phase angle can predict muscle mass status 12 months after kidney transplantation.

The Diagnostic Accuracy and Cutoff Value of Phase Angle for Screening Sarcopenia: A Systematic Review and Meta-Analysis

OBJECTIVES

Phase angle (PhA) declines with age and is a reliable marker for muscle function, making it a potential screening indicator for sarcopenia. However, studies examined the reliability and validity of PhA for detecting sarcopenia, yielding inconsistent results. This meta-analysis aimed to evaluate the accuracy and cutoff value of PhA for screening sarcopenia and examine the potential confounding factors.

DESIGN

This is a meta-analysis.

SETTING AND PARTICIPANTS

PubMed, Embase, and Cochrane Library were searched up to September 18, 2023. Eighteen studies (6184 participants) were included reporting the diagnostic accuracy of PhA for screening sarcopenia.

METHODS

Pooled accuracy [ie, the computed area under the curve value (AUC)] and cutoff value interval for screening sarcopenia were estimated using a random-effects model. Meta-regression analyses were conducted to identify sources of heterogeneity.

RESULTS

The AUC value was 0.81. Pooled sensitivity and specificity were 80% and 70%. The calculated 95% CI of the cutoff value of PhA for screening sarcopenia falls between 4.54° and 5.25°. The results of meta-regression analyses showed that ethnicity, body mass index (BMI), health status, and diagnostic criteria were the main factors affecting the diagnostic accuracy for screening sarcopenia (with all P values < 0.01).

CONCLUSION AND IMPLICATIONS

PhA may serve as a robust screening tool for sarcopenia, and the recommended cutoff interval falls between 4.54° and 5.25°. Ethnicity, BMI, health status, and diagnostic criteria can affect PhA's efficacy in sarcopenia screening.

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.

Phase angle and donor type are determinants of coronary artery calcification in stable kidney transplant recipients at twelve months after transplantation

BACKGROUND AND AIM

Coronary artery calcification (CAC) partially explains the excess cardiovascular morbidity and mortality after kidney transplantation. This study aimed to investigate determinants of CAC in stable kidney transplant recipients at 12 months post-transplantation.

METHODS AND RESULTS

CAC-score was quantified by the Agatston method using non-contrast enhanced computed tomography, and age- and sex-standardized CAC-percentiles were calculated. Univariable and multivariable multinomial logistic regression was performed to study potential determinants of CAC. The independent determinants were included in multivariable multinomial logistic regression adjusting for potential confounders. 203 KTRs (age 54.0 ± 14.7 years, 61.1% male) were included. Participants were categorized into four groups according to CAC percentiles (p = 0 [CAC-score = 0], n = 68; p ≥ 1%-p ≤ 50% [CAC score = 29.0 (4.0-166.0)], n = 31; p > 50 ≤ 75% [CAC score = 101.0 (23.8-348.3)], n = 26; and p>75% [CAC score = 581.0 (148.0-1652)], n = 83). Upon multivariable multinomial logistic regression, patients with a narrower phase angle and patients who had received a graft from a deceased donor had a higher risk of being in the >75th CAC-percentile.

CONCLUSIONS

This study identifies not only metabolic and transplant-related factors, but also phase angle, a composite marker of cell integrity, as an independent determinant of CAC at 12 months after kidney transplantation. This study offers new perspectives for future research into the value of bioelectrical impedance analysis in relation to vascular calcification in kidney transplant recipients.

The Role of Combined Muscle Ultrasound and Bioimpedentiometry Parameters for Sarcopenia Diagnosis in a Population of Hospitalized Older Adults

BACKGROUND

For the study of quantitative and qualitative muscle parameters, ultrasound and bioelectric impedance analysis are reliable, non-invasive, and reproducible. The aim of this study was to test the combined role of those techniques for the diagnosis of sarcopenia in a population of hospitalized older males and females.

METHODS

A total of 70 subjects were recruited, including 10 healthy adults and 60 hospitalized elderly patients with a good level of independence and cooperation, with and without sarcopenia. The rectus femoris cross-sectional area (CSA), thickness, echogenicity, and compressibility were measured with ultrasound echography. The phase angles (PhAs) and skeletal muscle mass were calculated by bioimpedence analysis. The muscle quality index (MQI) was calculated as the product of CSA and PhA.

RESULTS

Muscle compressibility was greater and PhA was lower in sarcopenic when compared with non-sarcopenic subjects. The threshold values for sarcopenia diagnosis in both sexes of CSA, of PhA, and of the MQI were identified. The obtained CSA values showed an AUC of 0.852 for women and 0.867 for men, PhA of 0.792 in women and 0.898 in men, while MQI was 0.900 for women and 0.969 for men.

CONCLUSIONS

The newly calculated cut-off values of CSA, PhA, and MQI predicted the presence of sarcopenia with good sensitivity and specificity values. The use of the MQI proved to be more promising than the separate use of CSA and PhA in both male and female subjects.

Prevalence of Musculoskeletal and Metabolic Disorders in Kidney Transplant Recipients: A Systematic Review and Meta-Analysis

Introduction

Musculoskeletal disorders could be associated with metabolic disorders that are common after kidney transplantation, which could reduce the quality of life of patients. The aim of this study was to assess the prevalence of both musculoskeletal and metabolic disorders in kidney transplant patients.

Methods

MEDLINE, CINAHL, Cochrane Library, EMBASE and Web of Science were searched from their inception up to June 2023. DerSimonian and Laird random-effects method was used to calculate pooled prevalence estimates and their 95% confidence intervals (CIs).

Results

21,879 kidney transplant recipients from 38 studies were analysed. The overall proportion of kidney transplant patients with musculoskeletal disorders was 27.2% (95% CI: 18.4-36.0), with low muscle strength (64.5%; 95% CI: 43.1-81.3) being the most common disorder. Otherwise, the overall proportion of kidney transplant patients with metabolic disorders was 37.6% (95% CI: 21.9-53.2), with hypovitaminosis D (81.8%; 95% CI: 67.2-90.8) being the most prevalent disorder.

Conclusion

The most common musculoskeletal disorders were low muscle strength, femoral osteopenia, and low muscle mass. Hypovitaminosis D, hyperparathyroidism, and hyperuricemia were also the most common metabolic disorders. These disorders could be associated with poorer quality of life in kidney transplant recipients.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier [CRD42023449171].

Assessing nutrition status, sarcopenia, and frailty in adult transplant recipients

The assessment of nutrition status, sarcopenia, and frailty holds significant relevance in the context of adult transplantation, as these factors are associated with an unfavorable prognosis; thus, transplant candidates must undergo a full nutrition assessment. Screening tools may be used to prioritize patients, this can be done using the Nutrition Risk Screening 2002 or Royal Free Hospital-Nutritional Prioritizing Tool. Subsequently, a thorough nutrition-focused physical examination should be conducted to evaluate clinical signs of nutrition deficiencies, fat and muscle loss, and fluid overload; dietary history and current intake must also be assessed. Apart from physical examination, specific testing for sarcopenia and frailty are recommended. For sarcopenia assessment, specifically for muscle quantification, the gold standard is the cross-sectional measurement of the muscle at L3 obtained from a computed tomography scan or magnetic resonance imaging; dual-energy x-ray absorptiometry is also a good tool especially when appendicular skeletal muscle index is calculated. Other more readily available options include phase angle from bioelectrical impedance or bioimpedance spectroscopy. In the sarcopenia assessment, muscle function evaluation is required, handgrip strength stands as the primary test for this purpose; this test is also part of the subjective global assessment and is included in some frailty scores. Finally, for frailty assessment, the Short Physical Performance Battery is useful for evaluating physical frailty, and for a multidimensional evaluation, the Fried frailty phenotype can be used. Specifically for liver transplant candidates, the use of Liver Frailty Index is recommended.

Association of phase angle with sarcopenia and muscle function in patients with COPD: a case-control study

BACKGROUND AND AIMS

The predictive value of phase angle for sarcopenia diagnosis has been discussed for years. The present investigation was conducted to determine the association between phase angle and sarcopenia in patients with COPD.

METHODS

In this case-control study, 222 smoker men were divided into healthy and COPD groups. COPD was diagnosed by a pulmonologist through spirometry. Anthropometric indices, phase angle, muscle function, sarcopenia, and dietary intake were assessed.

RESULTS

A significant inverse association was observed between phase angle and sarcopenia after adjustment for age and energy intake (OR: 0.31, 95% CI 0.18-0.52) and after adjustment for BMI (OR: 0.31, 95% CI 0.18-0.52). A significant decrease was detected in anthropometric indices and indicators of sarcopenia and muscle function in COPD cases compared to the healthy controls.

CONCLUSIONS

Although further studies are suggested, phase angle might be considered an indicator of sarcopenia and muscle function in COPD patients.

Use of bioimpedance in prevention of sarcopenia in the elderly

OBJECTIVES

Physiological ageing is associated with major and progressive changes in body composition, particularly in the decline of fat-free mass, which puts older individuals at risk of geriatric syndromes such as sarcopenia and sarcopenic obesity. Bioimpedance analysis noninvasively allows the determination of body composition, thus being able to rapidly assess primary risk factors leading to sarcopenia prediction.

METHODS

We conducted a study of 180 probands, 120 females (66.7%) with a mean age of 76.23 (SD = 9.29) years and 60 males (33.3%) with a mean age of 74.01 (SD = 8.99) years in cooperation with facilities for the elderly and with the inpatient department of the clinics of J.A. Reimann Hospital in Prešov. Body height, body weight, hip circumference, and waist circumference were determined by the anthropometric method, from which the values of the body mass index and waist-to-hip ratio were calculated. Active body mass, total body water, extracellular body water, intracellular body water, cell mass, body mass fat, body fat index, fat-free mass index, impedance at frequencies of 50 kHz, resistance, reactance, and phase angle were determined using the Quadscan 4000 Touch bioimpedance instrument. Appendicular skeletal muscle mass (ASMM) and muscle mass (ASMM/Ht2) were calculated. The data obtained from anthropometric and bioimpedance measurements were processed in MS Excel 2000 and STATISTICA ver. 12. The difference of means in the studied groups was tested by the t-test.

RESULTS

Presarcopenia was diagnosed in 12 (6.66%) probands out of 180 probands, of which were 3 (5%) men and 9 women (7.5%). Phase angle, ASMM and ASMM/Ht2 values were significantly lower (p < 0.001) in men and women with presarcopenia.

CONCLUSION

By introducing bioimpedance measurements into practice, it is possible to obtain results in a non-invasive way revealing possible presarcopenia in the elderly.

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

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

Frailty and sarcopenia in older kidney transplant recipients: a cross-sectional study

PURPOSE

The aging of the kidney transplant population is accelerating, and measures against geriatric syndromes including frailty and sarcopenia, which elevate the risk of needing long-term care and even death, are being considered important. Recently, both the frailty and sarcopenia criteria for Asians were revised based on various research reports and clinical experiences. The purpose of this study is twofold: firstly, to investigate the prevalence of frailty based on the revised Japanese version of the Cardiovascular Health Study (J-CHS) criteria and the Kihon Checklist (KCL) and that of sarcopenia based on the Asian Working Group for Sarcopenia (AWGS) 2019 as well as the relationship between frailty and sarcopenia, and secondly, to determine the concurrent validity of the KCL with the revised J-CHScriteria in older kidney transplant recipients.

METHODS

This study was a single-center cross-sectional investigation carried out on older kidney transplant recipients who visited our hospital from August 2017 to February 2019. The diagnosis of frailty was assessed using the revised J-CHS criteria and the KCL. The diagnosis of sarcopenia was made by low skeletal muscle mass and either low physical performance or low muscle strength based on the AWGS 2019. To examine the relationship between frailty and sarcopenia, categorical variables were compared using chi-squared test and continuous variables Mann-Whitney U test. Spearman's correlation analysis was used to investigate the correlation between the KCL score and the revised J-CHS score. The concurrent validity of the KCL for estimating frailty based on the revised J-CHS criteria was evaluated using the receiver operating characteristics (ROC) curve analysis.

RESULTS

A total of 100 older kidney transplant recipients were enrolled in this study. The median age was 67, 63 (63%) were males, and the median time after transplant was 95 months. The prevalence of frailty based on the revised J-CHS criteria and the KCL, and sarcopenia based on the AWGS 2019 was 15%, and 19%, and 16% respectively. Sarcopenia was significantly associated with frailty based on the KCL (p = 0.016), while not with frailty based on the revised J-CHS criteria (p = 0.11). The KCL score significantly correlated with the revised J-CHS score (p < 0.001). The area under the ROC curve was 0.91.

CONCLUSION

Frailty and sarcopenia are interrelated complex geriatric syndromes that are risk factors for adverse health outcomes. In older kidney transplant recipients, frailty and sarcopenia were highly prevalent and frequently co-existed. Furthermore, the KCL was verified as a useful tool for frailty screening in these patient. Easy identification of patients with frailty, which is reversible, can help clinicians institute appropriate corrective measures for kidney transplant recipients to improve transplant outcomes.

Neighbourhood transportation, elapsed years, and well-being after surrendering the driver's licence in older Japanese adults: The JAGES longitudinal study

This study aimed to examine how the associations between surrendering driving licence and changes in self-rated health and social interactions among older adults differ by the years elapsed since surrendering and the number of public transportation systems (PTS) in the neighbourhood. We used the 2013 and 2016 survey data from the Japan Gerontological Evaluation Study targeting residents aged ≥65 years in 30 municipalities in Japan. Two-waves longitudinal data from 4894 older adults were evaluated. Based on the difference-in-differences method, the interaction terms of respondents' driving status, which was the categorical exposure variable representing respondents' driving status for three years during the study period, and a dummy variable of year (2016) were used as explanatory variables in logistic regression analyses to examine changes in outcomes (poor self-rated health and infrequent meeting with friends) between 2013 and 2016 by driving status during this period. Analyses were stratified based on neighbourhood PTS ('more PTS' and 'fewer PTS' groups). We found that, while surrendering licence within three years was associated with increased probability of poor self-rated health in more PTS group, the confidence interval was large. Although surrendering licence within three years was associated with decreased social interactions, this association weakened if licence was surrendered more than three years ago. These associations were not markedly affected by neighbourhood PTS. Our findings suggested that, regardless of neighbourhood PTS, support and care to promote social interactions at or shortly after surrendering licence may be beneficial to the well-being of older adults who lost their driving licence.

Bioelectrical impedance analysis-derived phase angle predicts sarcopenia in patients on maintenance hemodialysis

BACKGROUND

This study aimed to investigate the association between phase angle (PhA) and sarcopenia and evaluate its performance as a sarcopenia predictor in patients receveing maintenance hemodialysis (MHD).

METHODS

All enrolled patients underwent handgrip strength (HGS) and the 6-m walk test, and muscle mass was measured using bioelectrical impedance analysis. Sarcopenia was diagnosed according to the diagnostic criteria of the Asian Sarcopenia Working Group. Logistic regression analysis was used to evaluate the PhA as an independent predictor of sarcopenia after adjusting for confounding factors. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of PhA in sarcopenia.

RESULTS

Two hundred forty-one patients receiving hemodialysis were enrolled in this study, and the prevalence of sarcopenia was 28.2%. Patients with sarcopenia presented a lower PhA value (4.7° vs 5.5°; P < 0.001), lower muscle mass index (6.0 vs 7.2 [kg/m² ]; P < 0.001), lower HGS (19.7 vs 26.0 [kg]; P < 0.001), and lower walk speed (0.83 ± 0.27 vs 0.92 ± 0.23 [m/s]; P = 0.007) than patients without sarcopenia. The odds of patients receiving MHD presenting with sarcopenia increased as PhA decreased, even after adjustment (odds ratio = 0.39; 95% CI, 0.18-0.85; P = 0.019). ROC analysis revealed that the best cutoff value of PhA for sarcopenia was 4.95° in patients receiving MHD.

CONCLUSION

PhA may be a useful and simple predictor for predicting patients undergoing hemodialysis who are at risk of sarcopenia. To further facilitate the application of PhA in the diagnosis of sarcopenia, more research need to be conducted.

Association of phase angle with sarcopenia in chronic musculoskeletal pain patients: a retrospective study

BACKGROUND

In chronic musculoskeletal pain patients, detection of sarcopenia is of significant clinical interest. Phase angle, which can be measured through bioelectrical impedance analysis (BIA), can detect sarcopenia; however, the evidence in chronic musculoskeletal pain patients is limited. This study aimed to assess the relationship between phase angle and sarcopenia in patients with chronic musculoskeletal pain. Our hypothesis was that phase angle would be a useful indicator to identify sarcopenia in patients with chronic musculoskeletal pain.

METHODS

A total of 190 patients (51 men and 139 women) with chronic musculoskeletal pain were included in this retrospective cross-sectional study. Patient data of backgrounds, numeric rating scale score for pain, skeletal muscle index, and phase angle assessed using BIA were retrospectively reviewed. Sarcopenia was diagnosed using the Asian Working Group for Sarcopenia criteria 2019.

RESULTS

A total of 51 patients (26.7%), including 10 men (19.6%) and 41 women (29.5%), were diagnosed with sarcopenia. Phase angle, sarcopenia-related factors, age, and body mass index (BMI) differed significantly in patients with and without sarcopenia. On multiple logistic regression analysis, the prevalence of sarcopenia was significantly correlated with phase angle and BMI. The areas under the curve exhibited high accuracy in discriminating sarcopenia in men and moderate accuracy in both sexes and in women.

CONCLUSIONS

Phase angle may be a valid discriminator of sarcopenia in patients with chronic musculoskeletal pain.

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

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

Phase angle derived from bioelectrical impedance analysis as a marker for predicting sarcopenia

Sarcopenia is commonly defined as the age-related loss of muscle mass and function and may be caused by several factors, such as genetics, environmental conditions, lifestyle, drug use, and, in particular, comorbidities. People with pre-existing conditions are more likely to develop sarcopenia and subsequently have a less favorable prognosis. Recently, phase angle (PhA), which is derived from bioelectrical impedance analysis (BIA), has received a great deal of attention, and numerous studies have been carried out to examine the relationship between PhA and sarcopenia in different conditions. Based on these studies, we expect that PhA could be used as a potential marker for sarcopenia in the future.

The combination of phase angle and age has a good diagnostic value for sarcopenia in continuous ambulatory peritoneal dialysis patients

Aims

There are limited studies on phase angle and sarcopenia in continuous ambulatory peritoneal dialysis patients. So, we want to explore the association between phase angle and sarcopenia and find a more sensitive indicator for diagnosing sarcopenia.

Methods

We included 101 continuous ambulatory peritoneal dialysis patients from March 2022 to August 2022 and measured the phase angle and body composition by bioelectrical impedance analysis. All patients had their handgrip strength measured. Then, we divided patients into the sarcopenia (n = 30) group and non-sarcopenia (n = 71) group according to the sarcopenia diagnostic strategy formulated by the Asian Working Group for Sarcopenia. We used logistic regression to explore the risk factors of sarcopenia. We applied Receiver-operating characteristics curves to determine the diagnostic accuracy of these risk factors.

Results

After adjustments for sex, age, diabetes, BMI, extracellular water ratio, extra water, serum creatinine, total kt/v, and residual kt/v, phase angle correlated to handgrip strength and lowered limb muscle mass but not to skeletal muscle mass, upper arm muscle circumference, upper limb muscle mass and appendicular skeletal muscle mass index. In the multivariate logistic model, low phase angle and older age are risk factors for sarcopenia. The AUROC of phase angle for sarcopenia is 0.79 (95%CI, 0.70–0.86, P &lt; 0.01) for both sexes, 0.70 and 0.85 for females and males. After we combined age and phase angle as diagnostic indicators of sarcopenia, the AUROC is 0.91 (95%CI, 0.83–0.96, P &lt; 0.0001) in both sexes, 0.89 and 0.93 for females and males.

Conclusion

This study illustrates that age 52 or older is an independent risk factor for sarcopenia in continuous ambulatory peritoneal dialysis patients. Phase angle can act as a predictor of sarcopenia in those patients. But the combination of age and phase angle is more valuable in diagnosing sarcopenia.

Efficacy of neuromuscular electrical stimulation with combined low and high frequencies on body composition, peripheral muscle function and exercise tolerance in patients with chronic kidney disease undergoing haemodialysis: a protocol for a randomised, double-blind clinical trial

INTRODUCTION

Neuromuscular electrical stimulation (NMES) as an adjunctive strategy to increase isolated muscular strength or endurance has been widely investigated in patients with chronic kidney disease (CKD) undergoing haemodialysis (HD). However, the efficacy of combined low and high frequencies, to improve both muscular strength and endurance, is unknown. This trial aims to evaluate the efficacy of this combined NMES strategy in this population.

METHODS AND ANALYSIS

This is a randomised controlled trial with blinded assessments and analysis. A total of 56 patients with CKD undergoing HD will be recruited and randomised to an NMES protocol. The evaluations will be performed on three different days at baseline and after 24 sessions of follow-up. Assessments will include the background, insulin-like growth factor, lactate measurement, malnutrition and inflammation score evaluation, an electrical bioimpedance examination, global muscular evaluation by means of the Medical Research Council scale, handgrip strength evaluation, muscular isokinetic evaluation of lower limbs, 6 min step test performance and quality of life (QoL) questionnaire with emphasis on physical function. The patients will be allocated in one of the following four groups: 1) combined low and high frequencies; 2) low frequency; 3) high frequency; and 4) sham stimulation with minimal intensity to generate only sensory perception (with no visible contraction). In all groups, the intensity throughout the session will be the highest tolerated by patient (except for control group). The primary endpoint is the change of peripheral muscle function (muscular strength and endurance). The secondary endpoints will be the changes of body composition; muscle trophism; exercise tolerance; QoL; and nutritional, inflammatory, and metabolic markers. The findings of this study are expected to provide valuable knowledge on how to optimise the NMES intervention, with improvements in both muscle strength and endurance.

ETHICS AND DISSEMINATION

This protocol has been approved by the Ethics Committee on Research with Humans of Hospital Sírio-Libanês (approval no. 24337707). Written informed consent will be obtained from each participant. The results of the study will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03779126.

Comparison of three nutritional screening tools for detecting sarcopenia in patients with maintenance hemodialysis

Background

Malnutrition, dynapenia, and sarcopenia are prevalent conditions among patients with maintenance hemodialysis (MHD). They are related to numerous adverse health outcomes. The aim of this study was to compare the effect of three nutritional screening tools on predicting the risk of dynapenia and sarcopenia in patients with MHD.

Methods

From July 2020 to April 2021, a total of 849 patients with MHD were enrolled at seven different healthcare facilities in Shanghai, China in this multi-center cross-sectional study. Geriatric nutritional risk index (GNRI), malnutrition inflammation score (MIS), and creatinine (Cr) index were used for nutritional assessment. The cutoff values of muscle mass and strength to define dynapenia, pre-sarcopenia, and sarcopenia were based on the consensus by the Asia Working Group of Sarcopenia in 2019.

Results

Among 849, almost 60% were malnourished with the majority suffering from dynapenia (27.7%), followed by sarcopenia (22.7%), and pre-sarcopenia (6.2%).The area under the receiver-operating characteristic curve for GNRI was 0.722 [95% confidence interval (CI) = 0.684-0.760] and 0.723 (95% CI = 0.663-0.783) in predicting sarcopenia and pre-sarcopenia. The GNRI [odds ratio (OR) =6.28, 95% CI: 4.05-9.73], MIS (OR =1.91, 95% CI: 1.31-2.78), and the Cr index (OR =2.73, 95% CI: 1.71-4.34) were all significantly associated with the risk of sarcopenia. More importantly, the sarcopenia predictability of the GNRI appears greater than the MIS and Cr index, while MIS was similar to the Cr index. Similarly, the superiority of GNRI prediction was also found in pre-sarcopenia, but not in dynapenia.

Conclusion

All the three nutritional screening tools were significantly associated with an increased risk of sarcopenia. The sarcopenia predictability of the GNRI was greater than the MIS and Cr index.

Associations between Advanced Glycation End Products, Body Composition and Mediterranean Diet Adherence in Kidney Transplant Recipients

There is limited evidence on the associations between dietary patterns, body composition, and nonclassical predictors of worse outcomes such as advanced glycation end products (AGE) in kidney transplant recipients (KTRs). The aim of this cross-sectional study was to determine the level of AGE-determined cardiovascular (CV) risk in Dalmatian KTRs and possible associations between AGE, adherence to the Mediterranean diet (MeDi), and nutritional status. Eighty-five (85) KTRs were enrolled in this study. For each study participant, data were collected on the level of AGE, as measured by skin autofluorescence (SAF), Mediterranean Diet Serving Score (MDSS), body mass composition, anthropometric parameters, and clinical and laboratory parameters. Only 11.76% of the participants were adherent to the MeDi. Sixty-nine percent (69%) of KTRs had severe CV risk based on AGE, while 31% of KTRs had mild to moderate CV risk. The results of the LASSO regression analysis showed that age, dialysis type, dialysis vintage, presence of CV and chronic kidney disease, C- reactive protein level, urate level, percentage of muscle mass, and adherence to recommendations for nuts, meat, and sweets were identified as positive predictors of AGE. The negative predictors for AGE were calcium, phosphate, cereal adherence according to the MeDi, and trunk fat mass. These results demonstrate extremely low adherence to the MeDi and high AGE levels related CV risk in Dalmatian KTRs. Lifestyle interventions in terms of CV risk management and adherence to the MeDi of KTRs should be taken into consideration when taking care of this patient population.

Body composition is associated with tacrolimus pharmacokinetics in kidney transplant recipients

PURPOSE

A population pharmacokinetic (popPK) model may be used to improve tacrolimus dosing and minimize under- and overexposure in kidney transplant recipients. It is unknown how body composition parameters relate to tacrolimus pharmacokinetics and which parameter correlates best with tacrolimus exposure. The aims of this study were to investigate which body composition parameter has the best association with the pharmacokinetics of tacrolimus and to describe this relationship in a popPK model.

METHODS

Body composition was assessed using bio-impedance spectroscopy (BIS). Pharmacokinetic analysis was performed using nonlinear mixed effects modeling (NONMEM). Lean tissue mass, adipose tissue mass, over-hydration, and phase angle were measured with BIS and then evaluated as covariates. The final popPK model was evaluated using goodness-of-fit plots, visual predictive checks, and a bootstrap analysis.

RESULTS

In 46 kidney transplant recipients, 284 tacrolimus concentrations were measured. The base model without body composition parameters included age, plasma albumin, plasma creatinine, CYP3A4 and CYP3A5 genotypes, and hematocrit as covariates. After full forward inclusion and backward elimination, only the effect of the phase angle on clearance (dOFV =  - 13.406; p < 0.01) was included in the final model. Phase angle was positively correlated with tacrolimus clearance. The inter-individual variability decreased from 41.7% in the base model to 34.2% in the final model. The model was successfully validated.

CONCLUSION

The phase angle is the bio-impedance spectroscopic parameter that correlates best with tacrolimus pharmacokinetics. Incorporation of the phase angle in a popPK model can improve the prediction of an individual's tacrolimus dose requirement after transplantation.

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

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

Sarcopenia in Non-Dialysis Chronic Kidney Disease Patients: Prevalence and Associated Factors

Background

Sarcopenia is related to morbidity and mortality in non-dialysis Chronic Kidney Disease (ND-CKD) patients; however, the pathophysiology of sarcopenia remains unclear. The study aimed to assess the prevalence and factors associated with sarcopenia in ND-CKD individuals.

Methods

We cross-sectionally evaluated 139 prevalent ND-CKD patients attending our outpatient clinic at Hospital das Clínicas of the Federal University of Pernambuco, between April and October 2019. Patients older than 18 years old and at G3-G5 CKD stages were included. Hand grip strength, Muscle Mass appendicular Index, and Gait Speed (GS) were defined by the standards of the European Working Group on Sarcopenia in Older People 2 guideline.

Results

Sarcopenia prevalence was 20.9% and severe sarcopenia 2.9%. Sarcopenic were mostly found in elderly ones (64.8 ± 13.5 years vs. 54.9 ± 12.8 years, p < 0.001), revealing lower body mass index [26.1 (6.8) vs. 28.6 (6.2), p = 0.023], lower phase angle (PhA) [4.50 (1.10) vs. 5.60 (1.20), p < 0.001] and lower GS [1.00 (0.50) vs. 1.40 (0.4), p < 0.001]. They also presented lower serum creatinine levels [2.40 (1.50) vs. 3.0 (1.8), p = 0.032], lower Albumin-to-Creatinine Ratio [72.60 (1008.30) vs. 342.30 (1172.1), p = 0.039] and Hemoglobin levels [11.45 (1.8) vs. 12.60 (2.40), p = 0.003], and higher levels of C-reactive protein [0.2 (0.80) vs. 0.03 (0.3), p = 0.045] compared to non-sarcopenic. Under Poisson Multivariate Model, PhA [Relative precision (RP): 0.364, Confidence Interval (CI) (95%):0.259-0.511, p < 0.001], Interleukin six (IL-6) [RP: 1.006, CI (95%):1.001-1.01, p = 0.02] and serum creatinine levels [RP: 0.788, CI (95%): 0.641-0.969, p = 0.024] were associated with sarcopenia.

Conclusions

Sarcopenia predominance was identified in our ND-CKD population, and was associated with lower PhA values, higher IL-6 levels, and lower serum creatinine levels.

Standardized Phase Angle for Predicting Nutritional Status of Hemodialysis Patients in the Early Period After Deceased Donor Kidney Transplantation

Background

This study was designed to verify whether early posttransplant standardized phase angle (SPhA) determines nutrition status of hemodialysis patients in regard to different nutritional markers and predicts handgrip strength (HGS) 6 months after kidney transplantation.

Methods

A total of 82 kidney transplant recipients on maintenance hemodialysis treatment entered the study. Nutritional status was evaluated before kidney transplantation, at the hospital discharge date, and 6 months after. We used bioelectrical impedance analysis (BIA), three different malnutrition screening tools, HGS, and anthropometric measurements. Demographic profiles and biochemical nutritional markers were collected. SPhA values, adjusted for age and BMI, were used in our study.

Results

In the early posttransplant period, kidney transplant recipients lost muscle mass, gained fat mass, and developed mostly negative SPhA, accompanied by significantly lower albumin levels. The subjects with lower than median (<-1.46) SPhA_dis [the SPhA (at discharge) adjusted for hospitalization time and the baseline SPhA] displayed lower values of albumin concentration (43.4 vs. 45.1 g/l, p = 0.010), hemoglobin (124 vs. 133 g/l, p = 0.016), GNRI (113 vs. 118, p = 0.041), and HGS (30 vs. 33 kg, p = 0.043). These patients had higher ferritin concentrations (420 vs. 258 mkmol/l, p = 0.026), longer inpatient stays (32 vs. 21 days, p < 0.001), and higher MIS scores (3 vs. 1, p = 0.001).

Conclusion

At the moment of hospital discharge, lower than the median SPhA is related to protein-energy wasting, represented as lower concentrations of nutrition biomarkers and an active inflammatory response. Higher SPhA before kidney transplantation predicts HGS 6 months after kidney transplantation, especially in women.

Focus on Nutritional Aspects of Sarcopenia in Diabetes: Current Evidence and Remarks for Future Research

Sarcopenia has been defined as a progressive and generalized loss of muscle mass that can be observed after the age of 40 years, with a rate of deterioration of about 8% every ten years up to 70 years, and 15-25% thereafter [...].

The Change in Muscle Mass Among Kidney Transplant Recipients: A Prospective Cohort Study

BACKGROUND

Recovery of renal function after transplantation leads to improved uremic conditions, increased physical activity, and liberation from severe dietary restrictions. Consequently, the muscle mass of kidney transplant recipients increases for several years after their transplant. However, the change in muscle mass and its associated factors among these patients remain largely unknown. Herein, we carried out a prospective cohort study with 1-year follow-up to investigate how muscle mass changes and to identify its risk factors among kidney transplant recipients.

PATIENTS AND METHODS

We performed a single-center, 1-year, prospective, observational cohort study from August 2017 to February 2019 at Osaka City University Hospital in Japan. The skeletal muscle mass index (SMI) was measured by bioelectrical impedance analysis. The risk factors related to the change in muscle mass were analyzed using multivariate linear regression models of age, sex, body mass index (BMI), dialysis vintage, transplant vintage, diabetes mellitus, hemoglobin, C-reactive protein, estimated glomerular filtration rate, and SMI at baseline.

RESULTS

A total of 180 kidney transplant recipients were enrolled in the present study. The median age was 55 years, and the median transplant vintage was 78 months. The median rate of change in SMI was +2.07%, and SMI increased in 118 (66%) patients during the 1-year follow-up. By multivariate analysis, the change in SMI at 1-year follow-up was independently associated with age (P = 0.017) and BMI (P = .023).

CONCLUSIONS

SMI increased in most of the kidney transplant recipients, and age and BMI might be the risk factors for this change in muscle mass among these patients.

A Combined Assessment Method of Phase Angle and Skeletal Muscle Index to Better Predict Functional Recovery after Acute Stroke

OBJECTIVES

We aimed to investigate whether combination assessment of phase angle (PhA) and skeletal muscle index (SMI), was a possible predictor of physical function at discharge from the hospital in patients with acute stroke.

RESEARCH METHODS AND PROCEDURES

In this retrospective cohort study that was conducted from May 2020 and July 2021, we determined PhA and SMI using bioimpedance analysis (BIA) in patients with acute stroke. Patients were classified as normal, low PhA + SMI group, pre-sarcopenia (low SMI only), and dynapenia (low PhA only) using cut-off points (men: SMI < 7.0 kg/m2, PhA < 4.05 degrees; women: SMI < 5.7 kg/m2, PhA < 3.55 degrees). The main outcome was physical function based on functional independence measure motor (FIM-motor) score at discharge. Multiple regression analysis was used to determine the association between low PhA + SMI and FIM-motor score.

RESULTS

We included 244 patients (161 men; mean age, 73.9 years). low PhA + SMI was found in 21 (8.6%) patients. Multiple regression analysis showed that low PhA + SMI was independently associated with the FIM-motor score at discharge (β= -0.099, 95%CI: -0.193,-0.005, p = 0.039). The PhA cutoff values for determining good functional results using receiver operating characteristic (ROC) curves were 5.36 for men (sensitivity = 0.769, specificity = 0.586, area under the curve [AUC] = 0.682), and 3.85 for women (sensitivity = It was 0.881, specificity = 0.481, AUC). Further, pearson correlation coefficient showed that PhA was significantly related to FIM-motor score in patients with mild or moderately severe stroke (mild: r = 0.472, p < 0.001; moderate: r = 0.524, p < 0.001).

CONCLUSIONS

Combination of low PhA and SMI values at baseline, was an independent predictor of physical function at discharge in patients with acute stroke. The findings highlighted the importance of measuring PhA and SMI using BIA in patients with acute stroke.

Association of endothelial dysfunction with sarcopenia and muscle function in a relatively young cohort of kidney transplant recipients

Background

Sarcopenia and endothelial dysfunction are both common among kidney transplant (KT) recipients. We aimed to evaluate the association between endothelial dysfunction and sarcopenia, as well as its individual components.

Methods

Vascular reactivity index (VRI), skeletal muscle index (SMI = skeletal muscle mass/height²), handgrip strength (HGS), and 6-meter usual gait speed (GS) were measured in 95 KT recipients. Low SMI was defined as SMI less than 10% of the sex-specific reference values from Chinese adults; low HGS as HGS < 28 kg for men and < 18 kg for women; slow GS as GS below 1.0 m/s. Sarcopenia was diagnosed based on the presence of low SMI as an essential criterion, accompanied by either low HGS or slow GS. Vascular reactivity was classified as being indicative of poor (VRI < 1.0), intermediate (1.0 ≤ VRI < 2.0), or good (VRI ≥ 2.0) vascular reactivity.

Results

Of the 95 patients, aged 45.2 ± 10.9 years, 11.6% had sarcopenia and 13.7% had poor vascular reactivity. Patients with sarcopenia were lower in body mass index (p = 0.001) and VRI (p = 0.041), and have a higher proportion of low muscle mass (p < 0.001), low HGS (p < 0.001), and slow GS (p = 0.001). Patients with poor vascular reactivity have a higher proportion of sarcopenia (p = 0.005), low HGS (p = 0.006), and slow GS (p = 0.029). Multivariate logistic regression analysis showed that patients in the poor VRI group were significantly associated with sarcopenia (odds ratio, OR = 6.17; 95% confidence interval [1.06-36.04]; p = 0.043), comparing to those with good VRI. We further analysed the effects of VRI on individual components of sarcopenia and found that VRI predicted slow GS significantly (OR = 0.41; 95% CI = [0.21-0.79]; p = 0.007), but not low SMI (OR = 1.15; 95% CI [0.53-2.49]; p = 0.718) and HGS (OR = 0.59; 95% CI [0.31-1.16]; p = 0.125).

Conclusions

We concluded that endothelial dysfunction is a key determinant of sarcopenia in KT recipients. Furthermore, endothelial dysfunction is more closely related to gait speed than muscle mass and strength.

Predictive value of phase angle in sarcopenia in patients on maintenance hemodialysis

OBJECTIVES

The aim of this study was to analyze the factors influencing sarcopenia in patients on maintenance hemodialysis (MHD) in mainland China and to explore the role of phase angle (PhA) in sarcopenia.

METHODS

We enrolled 346 patients on MHD with regular dialysis and collected relevant data. According to the diagnostic criteria of the Asian Sarcopenia Working Group, the patients were placed into one of two groups: sarcopenia and non-sarcopenia. The differences between groups were compared and the statistically significant factors were included in binary logistic regression analysis to screen for independent factors influencing sarcopenia. Receiver operating characteristic curve and area under the curve were used to evaluate the predictive value of PhA in sarcopenia.

RESULTS

The prevalence of sarcopenia was 32.66% in patients on MHD. Logistic regression analysis showed that sarcopenia was significantly associated with age (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.08-1.15; P < 0.001), body mass index (OR, 0.66; 95% CI, 0.58-0.76; P < 0.001), and PhA (OR, 0.24; 95% CI, 0.15-0.40; P < 0.001). The best cutoff value of PhA on sarcopenia was 4.67° for both sexes, 4.67° and 4.60° for men and women, respectively (P < 0.001).

CONCLUSION

The present study showed that PhA was an important influencing factor of sarcopenia adjusted by age and body mass index in Asian patients on MHD. PhA may have an optimistic predictive value to identify sarcopenia in these population, and it is convenient and accessible in clinical practice than the diagnostic criteria of sarcopenia.

Association Between Phase Angle and Sarcopenia in Patients Undergoing Peritoneal Dialysis

Introduction: There is limited data on the association between phase angle (PhA) and sarcopenia using both muscle strength and muscle mass in patients undergoing peritoneal dialysis (PD). We aimed to evaluate the association between PhA and sarcopenia in patients undergoing PD.

Methods: We enrolled prevalent patients undergoing PD (n = 200). The patients were divided into tertiles based on their PhA level: low (n = 66; 1.9–4°), middle (n = 68; 4.1–4.9°), and high tertiles (n = 66; 5–8°). PhA was measured by a bioimpedance analysis. Handgrip strength (HGS) was measured in all the patients. Body compositions were measured by dual energy x-ray absorptiometry (DXA).

Results: Handgrip strength (HGS) and/or lean mass indices showed poorer trends in the low tertile than in the other tertiles. PhA was positively associated with HGS and/or muscle mass index. Multivariate analyses showed that the patients in the low tertile had an odds ratio of 9.8 (p = 0.001) and 52.79 (p < 0.001) for developing sarcopenia compared with those in the middle and high tertiles, respectively. Subgroup analyses using these variables yielded results similar to those from the total cohort.

Conclusion: This study demonstrated that PhA is independently associated with muscle mass, strength, and sarcopenia in patients undergoing PD. This result suggests that PhA can be used as a valuable and simple predictor for identifying patients undergoing PD who are at risk of sarcopenia.

Sarcopenia measurement in research and clinical practice

Sarcopenia is a disease related to accelerated loss of skeletal muscle and subsequent decline in functional capacity. It affects approximately 13% of the world's population aged over 60 years. Sarcopenia is primarily managed and prevented through a combination of exercise prescription combined with appropriate nutritional strategies. This review outlines diagnostic and case finding/screening tools for age-related (primary) sarcopenia used in research and clinical practice. Diagnostic tools critically reviewed include those of the: European Workgroup for Sarcopenia (EWGSOP) versions 1 and 2; Asian Working Group for Sarcopenia (AWGS) versions 1 and 2; Foundation for the National Institutes of Health (FNIH); and the Sarcopenia Definition and Outcomes Consortium (SDOC). Criteria used by diagnostic tools (muscle mass, muscle strength and physical functioning/performance) are also detailed. Case-finding tools include the SARC-F questionnaire, Ishii's formula and Goodman's screening grid. Additionally, this review discusses the strengths and weaknesses of each diagnostic and case-finding tool, and examines their ability to reliably predict adverse clinical outcomes and patient responses to potential therapies.

Effect of Home Enteral Nutrition on Nutritional Status, Body Composition and Quality of Life in Patients With Malnourished Intestinal Failure

Background: The ultimate goal of intestinal failure (IF) management is to maintain optimal nutritional status, improve the quality of life (QoL), and promote intestinal adaptation. Enteral nutrition support is safe and effective in patients with IF and plays a central role in the management of patients with IF. The purpose of this study was to evaluate the effect of home enteral nutrition on nutritional status, body composition (BC), QoL and other clinical outcomes in malnourished patients with intestinal failure. Methods: This prospective observational study included 166 malnourished patients with intestinal failure presented to Jinling Hospital from January 2016 to October 2018. All patients were supported with home enteral nutrition after discharge. We evaluated clinical outcomes, including nutritional status, BC, phase angle (PhA), QoL, mortality, gastrointestinal complications related to enteral feeding, and other clinical outcomes at 1, 3, and 6 months after discharge. Results: Body weight, BC, and other nutritional parameters were maintained or significantly increased during the period of home enteral nutrition after discharge (p < 0.01). Especially, the quality of skeletal muscle mass in body composition was significantly improved (p < 0.01). SF-36 quality of life scores was significantly improved (discharged at 6 months: reported health transition 40.7 ± 12.1 vs. 69.3 ± 16.3, p < 0.01). There were no differences between hospital and out of hospital with respect to tube-related or gastrointestinal complications. Advanced age, disease type, and poor nutritional status were risk factors for poor clinical outcomes. Conclusions: Home enteral nutrition support is effective for malnourished patients with intestinal failure. It improves nutritional status, BC, PhA, and QoL. Clinical Trial Registration: identifier: ChiCTR2000035145.

Phase angle as a marker for muscle abnormalities and function in patients with colorectal cancer

BACKGROUND AND AIMS

Considering the applicability of phase angle (PhA) as a marker of muscle mass and function, we aimed to investigate whether PhA is a predictor of muscle abnormalities and function in patients with cancer.

METHODS

In a sample of patients with colorectal cancer (CRC), PhA was obtained from measurements of resistance and reactance from bioelectrical impedance analysis. Computerized tomography imaging at the third lumbar vertebra was used to evaluate muscle abnormalities by quantifying skeletal muscle index (SMI) and skeletal muscle radiodensity (SMD). Muscle function was assessed by handgrip strength (HGS) and gait speed (GS).

RESULTS

This cross-sectional study included 190 participants (X±SD), mean age 60.5 ± 11.3 years; 57% men; 78% had cancer stages III to IV. PhA was highly correlated with SMI (r = 0.70) and moderately correlated with HGS (r = 0.54). PhA explained 48% of the SMI variability (R² = 0.485), 21% of the SMD variability (R² = 0.214), 26% of HGS (R² = 0.261) and 9.8% of GS (R² = 0.098). In the multivariate model adjusted for age, sex, body mass index, performance status, comorbidities and cancer stage, 1-degree decrease in PhA was associated with low SMI (Odds Ratio (OR) = 6.56, 95% CI: 2.90-14.86) and with low SMI and HGS combined (OR = 11.10, 95% CI: 2.61-47.25). In addition, Receiving Operating Characteristics curve analysis showed that PhA had a good diagnostic accuracy for detecting low SMI, low SMI and SMD combined, low SMD and HGS and low SMI and HGS combined (AUC = 0.81, 95% CI: 0.74-0.88; AUC = 0.88, 95% CI: 0.81-0.95; AUC = 0.80, 95% CI: 0.70-0.91; AUC = 0.82, 95% CI: 0.74-0.89; respectively).

CONCLUSIONS

PhA was a predictor of muscle abnormalities and function and had a good diagnostic accuracy for detecting low muscle mass, low muscle mass and radiodensity, low muscle radiodensity and strength, and low muscle mass and strength in patients with CRC.

Association of Phase Angle, but Not Inflammation and Overhydration, With Physical Function in Peritoneal Dialysis Patients

Introduction: Muscle mass depletion, overhydration, and inflammatory state have been related to impaired physical function in chronic kidney disease patients. The relationship between bioelectrical impedance analysis (BIA) parameters, such as hydration status and phase angle (PhA), with physical function in peritoneal dialysis (PD), is still not well-established. Therefore, the objective was to evaluate the association of BIA parameters (overhydration index and PhA) and inflammatory markers with physical function in patients on PD.

Methods: The present cross-sectional study enrolled PD patients. Multifrequency BIA was performed to obtain overhydration index and PhA. The Short Physical Performance Battery (SPPB) test battery was applied to assess physical function. The time to complete the 4-m gait test and sit-to-stand test was also considered for physical function assessment. The inflammatory markers tumor necrosis factor-alpha and C-reactive protein levels were determined. Multiple linear regression models were performed, with the physical function variables as dependent variables, adjusted for age, diabetes, and sex.

Results: Forty-nine PD patients were enrolled, 53.1% (n = 26) women; mean age, 55.5 ± 16.3 years. There were significant correlations between PhA and SPPB (r = 0.550, p < 0.001), time of 4-m gait test (r = −0.613, p < 0.001) and sit-to-stand test and (r = −0.547, p < 0.001). Overhydration index was significantly correlated with SPPB, 4-m gait test (r = 0.339, p = 0.017), and sit-to-stand test (r = 0.335, p = 0.019). Inflammatory markers were not significantly correlated with physical function parameters. In the multiple linear regression analysis, PhA was associated with physical function parameters, even after adjustments. Overhydration index was associated with all physical function tests only in the models with no adjustments.

Conclusion: PhA was independently associated with physical function in PD patients. Inflammatory markers and overhydration index were not associated with physical function.

Relationship of phase angle and peak torque of knee extensors with the performance in six-minute step test in haemodialysis patients

BACKGROUND

Chronic kidney disease is a systemic disease affecting not only renal function, but also endocrine, cardiovascular, and skeletal muscle systems, with broad impact on functionality. Therefore, the assessment of body composition, peripheral muscle function, and exercise tolerance is also of great importance in this population. In addition, the development of reliable strategies that use feasible tools in clinical practice is of great importance in the functional diagnosis, clinical management and prescription of physical activity.

OBJECTIVE

To assess the relationship between phase angle and peak torque of knee extensors with the performance in six-minute step test of patients with chronic kidney disease undergoing haemodialysis.

METHODS

Observational and cross-sectional study at Haemodialysis Centre of Sírio-Libanês Hospital. The evaluations took place 3 days before the haemodialysis sessions. On the first day, patients underwent anthropometric evaluation and biochemical tests (lactate, urea, creatinine, albumin, ferritin and growth factor similar to insulin type 1 [IGF1]). On the second day, performed electrical bioimpedance and exercise tolerance assessed using the six-minute step test. On the last day, the evaluation of knee extensor muscles strength using isokinetic dynamometry was performed.

RESULTS

Eighteen subjects were included, with a mean age of 62.3 ± 17.6 years. A positive linear correlation was observed between the phase angle, derived from the electrical bioimpedance, and the performance in six-minute step test in these patients. It was also possible to observe a linear correlation between phase angle and IGF1, handgrip strength, peak torque of knee extensors and quality of life questionnaire. The peak torque of knee extensors also presented a linear correlation with IGF1, the performance in six-minute step test and mal-nutrition and inflammation score.

CONCLUSION

Phase angle and peak torque of knee extensors were correlated with the performance in six-minute step test. Therefore, the phase angle seems to be an important marker of reduced peripheral muscle function and exercise tolerance in haemodialysis patients.

Novel approaches to sarcopenic obesity and weight management before and after kidney transplantation

PURPOSE OF REVIEW

Although a widely recognized and complex pathophysiological condition, sarcopenic obesity remains less appreciated and may elude diagnosis and workup in both kidney transplant waitlisted candidates and kidney transplant recipients. The lack of consensus definition, and practical diagnostic tools for evaluating waitlisted candidates and transplant recipients are barriers to early detect and initiate therapeutic management for sarcopenic obesity. Although sarcopenia leads to poor clinical outcomes, posttransplant obesity yields conflicting results. Exercise and nutritional managements are common therapies for sarcopenic obese patients; however, surgery weight loss or bariatric surgery in both transplant candidates and potential living kidney donors shows promising benefits for kidney transplant access in waitlist obese candidates but may require to be selected for appropriate patients.

RECENT FINDINGS

Pathogenesis and management for sarcopenia and obesity are interconnected. The benefits of exercise to improve muscle mass and function is clear in waitlist kidney transplant candidates and transplant recipients. However, there are several barriers for those to increase exercise and improve physical activity including patient, provider, and healthcare or environmental factors. The advantages of fat mass reduction to lose weight can promote muscle mass and strength. However, epidemiological data regarding the obesity paradox in dialysis-dependent patients when overnutrition provides survival benefits for this population should be taken into account when performing weight loss especially bariatric surgery.

SUMMARY

Barriers in providing optimal care to kidney transplant waitlisted candidates and transplant recipients may partly result from underdiagnosis of sarcopenic obesity; notwithstanding that this entity has increasingly been more recognized. Mechanistic studies to better understand pathogenesis of sarcopenic obesity will help determine pathogenesis and clinical tools for diagnosis of this entity, which can facilitate further studies related to the outcomes and weight management to ultimately improve kidney transplant outcomes.