The Association Between Handgrip Strength and Predialysis Serum Sodium Level in Patients With Chronic Kidney Disease Stage 5D.

Anastasia Markaki,Helen Drosataki,Aspasia Spyridaki,Ioannis Petrakis,Periklis Kyriazis,Eleftheria-Kleio Dermitzaki,Kostas Stylianou,Emmanuel Psylinakis,Dimitra Lygerou,Sevasti Maragou,Maria G Grammatikopoulou

doi:10.3389/fmed.2020.610659

Abstract

Purpose: Handgrip strength (HGS) is a useful tool for the systematic assessment of muscle function related to nutritional status. Reduced HGS has been associated with adverse clinical outcomes in chronic kidney disease (CKD) stage 5D patients. In the same patients, predialysis low serum sodium (sNa) has been associated with malnutrition and mortality. Here, we investigated the role of predialysis sNa on muscle function in CKD-5D patients.Methods: We evaluated 45 patients on hemodialysis (HD) and 28 patients on peritoneal dialysis (PD) with HGS measurement, bioimpedance analysis, anthropometric measures, and malnutrition inflammation score (MIS). According to established diagnostic criteria, reduced HGS was defined as strength below 30 and 20 Kg in men and women, respectively. Predialysis sNa values were defined as the mean of all predialysis measurements during the preceding 6 months. Data analysis was performed separately for each of the HD and PD groups.Results: The proportions of reduced HGS did not differ between the HD (66%) and PD (54%) groups, respectively. Patients in the HD group as compared to those in the PD group had higher serum albumin and potassium and mid-arm muscle circumference and lower residual renal function (RRF) and residual urine volume. Multivariate logistic analysis, after controlling for muscle mass, nutritional biomarkers, MIS, fluid overload and RRF, showed that for every 1 mmol/l increase of sNa the odds of reduced HGS was decreased by 60% (OR = 0.40, 95% CI: 0.16–0.99) and 42% (OR = 0.58, 95% CI: 0.36–0.93) in HD and PD patients, respectively. However, stratified analysis indicated that lower sNa levels predicted reduced HGS in individuals with a background of malnutrition, inflammation, overhydration and less preserved RRF, representing unfavorable conditions strongly related to muscle wasting in the dialysis setting.Conclusions: Predialysis sNa is a strong and independent determinant of HGS, a reliable nutritional marker in CKD-5D stage patients. However, according to our findings, lower sNa levels appear to be a marker of underlying unfavorable conditions that are heavily associated with reduced HGS, rather than a causal determinant of reduced HGS. Whether optimizing sNa levels improves patient muscle performance requires further investigations.

Highlights

Protein-energy wasting (PEW) is defined as a pathological state where there is a continuous decrease or wasting of both protein deposits and energy reserves [1]
The results of our stratified analysis indicated that the association between lower sNa levels and reduced Handgrip strength (HGS) was most apparent in malnourished HD patients with higher levels of inflammation, higher degrees of over-hydration, lower levels of Residual renal function (RRF) and in hypo-albuminemic PD patients with anthropometric evidence of under-nutrition by TSF
The negative correlations of HGS with age, Malnutrition-inflammation score (MIS), and extracellular water to total body water (ECW/TBW) and the positive ones with male gender, mid-arm muscle circumference (MAMC), fat-free mass index (FFMI), skeletal muscle index (SMI), Serum levels of albumin (sAlb), creatinine, and RRF are in agreement with previous studies [7,8,9] and support the validity of our dataset

Summary

Introduction

Protein-energy wasting (PEW) is defined as a pathological state where there is a continuous decrease or wasting of both protein deposits and energy reserves [1]. HGS, a measurement of the maximal voluntary force of the hand/arm, has emerged as a simple and reliable method of assessing muscle function and indirectly the nutritional status in the general population [6] and patients with CKD [7, 8]. Several studies showed that reduced HGS could independently predict adverse health outcomes, such as inflammation, malnutrition, over-hydration, and higher mortality and morbidity in CKD populations [9,10,11,12,13]. These data further reinforce the systematic use of HGS in the assessment of muscle function related to nutritional status in the CKD setting

Objectives

Methods

Results

Discussion

Conclusion