The association between changes of gustatory function and changes of salivary parameters: A pilot study

Objective: The aim of the pilot study was to explore which of the salivary parameters best reflects improvement or deterioration of taste function. Methods: A total of 14 patients were included. Taste ability was measured using taste strips and patients rated their symptom strength using visual analogue scales. Salivary parameters (flow rate, total proteins, proteolysis, catalase, total anti-oxidative capacity [TAC], carbonic anhydrase VI [caVI], and pH) were determined and the Beck Depression Inventory (BDI) was administered. All these parameters were measured twice with a one-year interval to acquire the changes of data. Results: Patients with decreased taste function exhibited a decrease in salivary proteolysis and caVI, and an increase in salivary total protein. Patients with increased taste function also showed an increase in salivary total protein. Delta Salivary flow rate was negatively correlated with Delta taste strip scores. Delta Salivary pH was significantly lower in patients with increased taste function compared to patients with decreased taste function. Delta BDI was positively correlated with both Delta symptoms ratings. Across all patients, symptom ratings decreased while salivary total protein increased; salivary flow rate, proteolysis and caVI decreased significantly compared with baseline. Conclusions: The present longitudinal results suggest that changes of both taste function and taste complaints were accompanied by changes in salivary parameters, indicating that salivary parameters have the potential to be useful in the diagnosis of patients with qualitative taste disorders.