Markaki Anastasia, Kyriazis Periklis, Dermitzaki Eleftheria-Kleio, Maragou Sevasti, Psylinakis Emmanuel, Spyridaki Aspasia, Drosataki Helen, Lygerou Dimitra, Grammatikopoulou Maria G, Petrakis Ioannis, Stylianou Kostas
Department of Nutrition and Dietetics Sciences, Hellenic Mediterranean University, Crete, Greece.
Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
Front Med (Lausanne). 2021 Jan 12;7:610659. doi: 10.3389/fmed.2020.610659. eCollection 2020.
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. 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. 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. 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.
握力（HGS）是系统评估与营养状况相关肌肉功能的一项有用工具。慢性肾脏病（CKD）5D期患者中，握力降低与不良临床结局相关。在这些患者中，透析前低血清钠（sNa）与营养不良及死亡率相关。在此，我们研究了透析前sNa在CKD-5D期患者肌肉功能中的作用。我们对45例接受血液透析（HD）的患者和28例接受腹膜透析（PD）的患者进行了评估，测量其握力、进行生物电阻抗分析、人体测量，并计算营养不良炎症评分（MIS）。根据既定诊断标准，男性和女性握力降低分别定义为力量低于30千克和20千克。透析前sNa值定义为前6个月内所有透析前测量值的平均值。分别对HD组和PD组进行数据分析。HD组（66%）和PD组（54%）握力降低的比例无差异。与PD组患者相比，HD组患者血清白蛋白、钾水平及上臂中部肌肉周长更高，而残余肾功能（RRF）和残余尿量更低。在控制肌肉质量、营养生物标志物、MIS、液体超负荷和RRF后进行多因素逻辑分析，结果显示，HD和PD患者中，sNa每升高1 mmol/L，握力降低的几率分别降低60%（OR = 0.40，95% CI：0.16 - 0.
