Salt taste threshold and contributory factors of chronic kidney disease patients: a cross-sectional study

High salt intake, correlated with high salt taste threshold, may accelerate renal injury in chronic kidney disease (CKD) patients. However, few studies have focused on factors that influence salt taste threshold. Therefore, we aimed to identify factors that influence the salt taste threshold of CKD patients, to provide more precise salt restriction recommendations in dietary therapy.

Between April 2016 and March 2019, we measured the salt taste threshold of 1019 CKD patients, aged 22-78 years, from 52 hospitals across southwestern China, and then we performed a cross-sectional study.

The mean salt taste threshold was 0.37 ± 0.16% NaCl. There were 115 (11.3%), 670 (65.7%), and 234 (23.0%), respectively, patients who had low (≤ 0.1% NaCl), medium (0.1-0.4% NaCl), and high (> 0.4% NaCl) salt taste thresholds. One-way ANOVA and regression results revealed that sex (male), age, decreased estimated glomerular filtration rate, and absence of salt restriction were factors that influenced CKD groups with high salt taste threshold.

We found an independent correlation between contributory factors including sex, age, eGFR, and salt restriction behavior of subjects with the salt taste threshold of CKD patients. Our findings also offer insights on salt taste thresholds that could be useful for clinicians advising salt restriction to impair the salt taste sensitivity of the corresponding populations.