Clinical Taste Perception Test for Patients With End-Stage Kidney Disease on Dialysis

The aim of this study was to validate a direct taste perception test (TPT) and evaluate its performance in patients on dialysis.

This cross-sectional study was carried out in a tertiary-care hospital. A TPT was validated on 112 healthy subjects and applied on 43 patients on hemodialysis and 32 patients on peritoneal dialysis. All participants were presented a 10-mL sample to identify and rate intensity of primary tastes: sweet (sucrose 2%), sour (citric acid 0.1%), bitter (caffeine 0.06%), salty (sodium chloride 0.5%), and umami (sodium glutamate 0.25%). The internal consistency and repeatability of TPT was assessed by Cronbach's alpha and intraclass correlation coefficient. Chi-square and Mann-Whitney U tests were used to compare groups.

TPT had Cronbach's alpha of 0.77. Intraclass correlation coefficient was 0.74 for sweet, P < .0001; 0.57 for salty, P = .001; 0.62 for sour, P < .0001; 0.78 for bitter, P < .0001; and 0.76 for umami, P < .0001. Compared with controls, patients on peritoneal dialysis were less able to identify sweet and umami tastes (P < .05) and marginally (P = .06) sour taste, whereas patients on hemodialysis were marginally (P = .06) less able to identify sweet and salty tastes. Bitter was not differently identified between groups. According to the visual analog scale (0-10), all patients on dialysis perceived sour taste less intensely than control subjects (P < .05).

This TPT for patients on dialysis had adequate reliability to identify five primary tastes in a clinical setting. Except for bitter taste, perception of all the primary tastes was altered in patients on dialysis compared with control subjects. A broader use of this test would help identify taste alterations and implement strategies for malnutrition.