Association of Serum Serotonin Levels, and Hyperglycemia with Ageusia and Anosmia in Iraqi COVID-19-Infected Patients

Background: Serotonin plays a significant neuro-modulatory role in olfactory neurons and taste receptor cells. Aim: This study was conducted to examine and comparison between serum levels of serotonin in active Iraqi COVID-19 patients (with or without anosmia and ageusia) and healthy individuals. Also, the correlation between serotonin serum levels and hyperglycemia in each of the study groups was evaluated and compare it with control group. Methods: The participants were divided into three groups: 30 active COVID-19-infected patients who had anosmia and ageusia (Group 1), 30 patients who were infected and had no anosmia and ageusia (Group 2), and 30 healthy subjects who served as controls (Group 3). Results: All the samples were thawed and used to evaluate the levels of serum serotonin. Likewise, a colorimetric approach was employed to measure the levels of serum FBG and the (SPSS, version 25) was used to analyze the data, it was observed that the mean amounts of serum serotonin were significantly (p < 0.0001) lower in group 1 compared with groups 2 and 3, while mean, the average serum levels of glucose were significantly higher in group 1 (p < 0.0001), as compared with groups 2 and 3. Conclusion: Serotonin levels was decreased in patients who had COVID-19 infections along with anosmia and ageusia, which helps with the prediction of anosmia and ageusia associated with the other diseases. In addition, there is an inverse relation between blood glucose level and serotonin.