High-Salt Diet Accelerated the Decline of Residual Renal Function in Patients With Peritoneal Dialysis

Nirong Gong,Yanhong Lin,Tingting Zhang,Xianhui Qin,Chun Zhou,Zhixiu Yi,Jianping Jiang,Jianxia Hu,Xiaohong Zhong,Jianwei Tian,Liping Hu,Cong Yang

doi:10.3389/fmed.2021.728009

Abstract

Objective: This study aims to investigate the relationship between dietary salt intake and residual renal function in peritoneal dialysis (PD) patients.Methods: The daily salt intake of the patients was calculated based on a 3 day dietary record. Sixty-two patients were divided into three groups: 33 patients in the low salt intake group (salt intake <6.0 g/day), 17 in the medium salt intake group (salt intake 6.0 to <8.0 g/day), and 12 in the high salt intake group (salt intake ≥8.0 g/day). Regular follow-up was conducted every 3 months. Urine volume, peritoneal ultrafiltration volume, and other clinical indicators were recorded. Biochemical indexes were detected to evaluate the changes in residual renal function and peritoneal function during follow-up.Results: A positive correlation between dietary sodium intake and sodium excretion was found. During 12-month follow-up, a decrease of residual renal function showed a significant difference among the three groups (p = 0.041) (15.3 ± 27.5 vs. 12.5 ± 11.5 vs. 32.9 ± 18.4 L/W/1.73 m2 in the low-, medium-, and high salt intake groups, respectively). Consistently, a higher decline of residual renal function (adjusted β, 20.37; 95% CI, 2.83, 37.91) was found in participants with high salt intake (salt intake ≥8 g/day) compared with those in non-high salt intake.Conclusion: Our study showed that the sodium excretion by peritoneal dialysis was positively correlated with dietary sodium intake in PD patients. The high salt intake diet (salt intake ≥8 g/day) may lead to a faster decline of residual renal function in PD patients.

Highlights

Residual renal function (RRF) is defined as the ability of the native kidneys to eliminate water and uremic toxins, and the presence of RRF is associated with prolonged survival and a better quality of life in peritoneal dialysis (PD) patients with end-stage renal disease (ESRD) [1,2,3]
There were no significant differences in age, sex, body mass index (BMI), baseline dialysis vintages, and other demographic data among the three groups
The present study showed that the sodium excretion was positively correlated with dietary sodium intake in PD patients

Summary

Introduction

Residual renal function (RRF) is defined as the ability of the native kidneys to eliminate water and uremic toxins, and the presence of RRF is associated with prolonged survival and a better quality of life in peritoneal dialysis (PD) patients with end-stage renal disease (ESRD) [1,2,3]. Salt Intake and Renal Function kidney disease (CKD) and high salt intake accelerated the progression of renal injury [6]. Another study showed that highsalt diet could accelerate the loss of RRF in patients with CKD [7, 8]. Whether the salt intake should be limited in PD patients was unclear. Fewer studies have evaluated the relationship between salt intake and residual renal decline in PD patients

Methods

Results

Conclusion