Factors associated with gustatory threshold for salty taste in peritoneal dialysis patients
Taste disorder is a common problem in patients with chronic kidney disease and end-stage renal disease. Specifically, salty taste disorder is associated with excess salt intake. Many factors affect taste activity; however, data focused on peritoneal dialysis (PD) patients are limited. This study aimed to investigate the distribution of the gustatory threshold for salty taste and to clarify its relevant contributing factors in PD patients. In this retrospective cross-sectional study, we enrolled 22 PD patients who were assessed for their detection and recognition thresholds for salty taste using salt-impregnated test strips. We investigated the distribution of the detection and recognition thresholds and analyzed their relevant factors. In PD patients, detection and recognition threshold for salty taste were both high. Especially, most of the PD patients could not recognize salty taste even at the highest concentration level. The high detection threshold was associated with young age, long duration of PD, high serum phosphorus, and high transferrin saturation. The high recognition threshold was associated with long duration of PD, high serum phosphorus, high creatinine, high serum β2 microglobulin, low renal Kt/V, and high peritoneal Kt/V. Partition analysis showed that high serum phosphorus was related with high detection threshold and low renal Kt/V was related with high recognition threshold. This study demonstrated that the gustatory threshold for salty taste was increased in PD patients. In addition, high detection threshold was related with high serum phosphorus and high recognition threshold was related to low renal Kt/V. Based on these findings, we consider that it is important to assess the gustatory threshold for salty taste in PD patients, particularly those with high serum P and low renal Kt/V.