#2674 ASSOCIATION BETWEEN SARCOPENIA, BODY COMPOSITION AND FRAILTY IN PERITONEAL DIALYSIS PATIENTS: A MULTI-CENTRIC STUDY
Authors: Mauricio Miguel Nuno Petrucci , Merino Jaime Hernán , Carnevale Andreia , Pereira Sofia Azeredo , Martins Ana Rita , Calça Rita , Matias Patricia , Castellano Barbara Cancho , Perez-Monteoliva Nicolas-Roberto Robles , Branco Patricia 
Published: June 2023

Abstract

Background and Aims
Patients with chronic kidney disease (CKD) have an increased risk of mortality due to many causes. One of them is sarcopenia, a progressive skeletal muscle disorder that increases adverse outcomes such as fractures, falls, and physical disability, and has been considered an independent risk factor for mortality. Sarcopenia could be defined as a muscle failure in which muscle strength is the most solid measure of muscle function and a better predictor of adverse events rather than muscle mass. Grip strength is considered a reliable surrogate for measures of arm and leg strength. The aim of this study was to evaluate the prevalence of probable sarcopenia in peritoneal dialysis (PD) patients and its association with body composition and several clinical variables.

Method
This retrospective multi-centric descriptive study was conducted at the Hospital de Santa Cruz (Lisboa) and Hospital Universitario de Badajoz (Badajoz). We performed a single evaluation of 62 patients on peritoneal dialysis from at least 3 months, aged &gt;18 years in whom we measured muscle strength by handgrip strength using a dynamometer. We divided patients into two groups, using cut-off points to consider probable sarcopenia for men and women less than 27 kg and 16 kg, respectively. Patients with acute infection, amputated limbs, and implantable cardiac devices were excluded. The following data were analyzed: age, anthropometric variables, gender, duration, modality of PD, presence of hypertension, diabetes, and cardiovascular disease, obtained from electronic medical records. We also analyze data from body composition using a bioelectrical impedance device (overhydration, extracellular intracellular water ratio (E/I), lean and fat tissue index and phase angle), PD parameters (weekly urea Kt/v, nGFR, D/P Cr, nPCR, residual urine output) and measured serum concentrations of hemoglobin, PCR, NT-ProBNP, PTH, Ca-125, calcium, and phosphorus. We assessed patients for the Clinical Fragility Scale (CFS) and measured performance in activities of daily living using the Barthel Scale.

Results
Records of 62 patients, 61% male, mean age 57 ± 22 years, and body mass index 27.5 ± 5.1 kg/m2 were reviewed, with 15 (18.8%) classified as probable sarcopenic. Old age (p = 0.005), high CFS score (p = 0.005), E/I ratio (p &lt; 0,001), and low values of lean tissue index (p &lt; 0.031), mean phase angle (p &lt; 0.001) and residual urine output (p &lt; 0,018) were correlated with the presence of probable sarcopenia. In the multivariable analysis, age (HR 1.135; CI 95% 1.015 - 1.269), CFS score (HR 2.637; CI 1,008 - 6,900), and urine output (HR 0,996; CI 95% 0.993 - 0.999) were also related to probable sarcopenia. There was no association between the presence of anemia, cardiovascular disease, type of peritoneal transport, and clearance of small solutes.

Conclusion
This study reported a low prevalence of probable sarcopenia in PD patients. We corroborate the association between age and frailty in the sarcopenic group. The percentage of extracellular water, muscle mass, and phase angle measured by bioimpedance could be useful variables to identify sarcopenic or at-risk patients. In multivariate analysis, age, higher CFS score, and urine output have been associated with sarcopenia. Preservation of residual renal function seems to be associated with less sarcopenia, which reinforces the importance of preserving residual renal function in PD patients. It's also important to identify sarcopenic or at-risk patients in order to promote early detection and treatment.