Salty taste thresholds and preference in patients with chronic kidney disease according to disease stage: A cross-sectional study.

Aim: The present study was performed to evaluate the differences in salty taste thresholds among normal controls and non-dialysis chronic kidney disease (CKD) patients according to disease stage and to evaluate the relationship between salty taste thresholds or preferences and mean spot urine sodium concentrations.

Methods: This cross-sectional study enrolled 436 patients with non-dialysis CKD and 74 normal controls. We evaluated detection and recognition thresholds, salty taste preferences and salt usage behaviours (through a questionnaire) in CKD patients and normal controls. We averaged the three most recent spot urine sodium concentrations and used this 'mean spot urine sodium' value to estimate sodium intake in CKD patients.

Results: Detection thresholds of stages 3 and 5 and recognition thresholds of stage 3 CKD patients were higher than those of normal controls. Salty taste preferences of stage 5 and salt usage behaviour scores of stages 4 and 5 CKD patients were lower than those of normal controls. Univariate analysis showed that estimated glomerular filtration rate (eGFR), salt usage behaviour score, salty taste preference, smoking, gender and zinc level were significantly associated with mean spot urine sodium in CKD patients. Multiple regression analysis showed that the eGFR and salty taste preference were independently correlated with mean spot urine sodium.

Conclusions: Education to change salty taste preferences and regular follow up are necessary to decrease salt intake in CKD patients.