Abnormalities in acute salivary biochemical characteristic responses to gustatory stimulation with citric acid in chronic non-atrophic gastritis.

Background and Aim: Salivary characteristics are altered in gastrointestinal diseases and related to oral taste disorder. However, specific salivary biochemical characteristics and their relationships with oral taste disturbances in chronic non-atrophy gastritis (CNAG) remain uncertain.
Methods: Seventy patients with CNAG and 70 subjects in healthy control group (HCG) were enrolled in our study. The levels of salivary flow rate (SFR), pH, salivary α-amylase (sAA) activity, total protein density (TPD), chloride concentration, and calcium concentration were determined before and after citric acid stimulation and compared between CNAG with and without oral taste disturbances.
Results: Average body mass index (BMI) of CNAG (17.75 ± 2.08) was lower than that of HCG (21.96 ± 1.72, P < 0.01). Compared with HCG, CNAG showed increased TPD and calcium concentration but decreased SFR both before and after acid stimulation (P < 0.01), as well as reduced sAA and salivary chloride responses to acid stimulation (P < 0.01). Compared with CNAG with normal BMI (24.29%, 17/70), sAA activity response to acid stimulation was reduced in those with low BMI (75.71%, 53/70, P < 0.05). Under resting condition, CNAG with dry mouth (55.71%, 39/70) showed increased SFR and decreased TPD (P < 0.05), as compared with CNAG without dry mouth (44.29%, 31/70). Compared with CNAG without bitter taste (57.14%, 40/70), pH was decreased in those with bitter taste (42.86%, 30/70) under both resting and stimulated conditions (P < 0.05).
Conclusion: Decreased sAA activity may reflect malnutrition state and be one potential marker of poor digestion, decreased salivary pH may contribute to bitter taste perception, and reduced TPD might be a cause of dry mouth in CNAG.
(© 2018 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)