Objective Evaluation of Smell and Taste Senses in COVID-19 Patients

Abstract

Objective: The severe acute respiratory syndrome‐coronavirus‐2 pandemic is one of the largest of the recent times and can cause many symptoms including smell and taste disorders. In the literature, smell disorders caused by coronavirus disease-2019 (COVID-19) have been reported within a wide range from 3.2% to 98.3%. A small number of these studies demonstrated smell and taste disorders through objective tests. Our aim in this study was to determine the prevalence of smell and taste disorders in hospitalized patients due to COVID-19 infection. Methods: The study was carried out with 100 patients who were positive for real-time polymerase chain reaction and treated at the Kayseri City Hospital, and 100 healthcare worker relatives. We used the Connecticut Chemosensory Clinical Research Center test to evaluate the sense of smell. Sense of taste was evaluated using four different standardized bottles of preparations, and the results were scored according to the patients’ statements. Results: Patient (Group 1) and control (Group 2) groups were compared for age, gender, smell and taste disorders. There were 39 women and 61 men in the patient group, and 40 women and 60 men in the control group. Mean age was 50.2±1.37 (range 21–70) years in Group 1 and 47.6±1.25 (range 18–70) years in Group 2, and there was no significant difference between the two groups. While the rate of smell disorder was 80% in Group 1, we found this rate as 35% in Group 2. Taste disturbance was identified in 38 patients, of whom 16 had mild hypogeusia, 17 had moderate hypogeusia, four had severe hypogeusia, and one patient had ageusia. We found that taste disorder was 38% in Group 1 and 3% in Group 2. Conclusion: Smell and taste dysfunctions are very common symptoms in COVID-19 patients. The results obtained using objective test methods are higher than the rates obtained from patient statements.

Prevalence of Olfactory Dysfunction with the Omicron Variant of SARS-CoV-2: A Systematic Review and Meta-analysis

“…It is currently controversial whether psychophysical testing or subjective recall is the most valid and sensitive approach to assess COVID-related chemosensory dysfunction [21,27]. Among studies that compared the two types of methods, about half of them concluded that objective testing is more sensitive than subjective testing [112-115]. The other half concluded the opposite, that subjective testing is more sensitive than objective testing [116-120].…”

“…Among studies that compared the two types of methods, about half of them concluded that objective testing is more sensitive than subjective testing [112][113][114][115].…”