Self-reported olfactory and gustatory dysfunction in patients with COVID-19 infection

Objective: To investigate the incidence, comorbidity and recovery period of smell and taste loss in patients with COVID-19 infection, who were treated as outpatient or admitted to the hospital. Methods: 103 patients with COVID-19 infection were recruited from a COVID-19 Test Centre (CTC) and hospital wards. Subjects filled in an online self-report survey retrospectively at least six months after recruitment. The following epidemiological and clinical outcomes have been studied: age, gender, comorbidities, general and otolaryngological symptoms and recovery of the olfactory or gustatory loss. Results: All patients suffered from mild to severe respiratory disease. A high frequency of smell and taste dysfunctions was reported (71.2% and 78.9% respectively). 33% of the patients reported anosmia and 33% reported ageusia. The most frequent symptoms were fever, loss of smell and taste, dyspnoea and headache. The most common comorbidities were hypertension, obesity and diabetes. Males suffered 2.6 times more often from olfactory dysfunction than females. No statistical difference with regard to recovery time were found between man and women. There was a significant difference in the sense of taste scores before COVID-19 infection and during COVID-19 infection. Smell and taste dysfunction was related to clinical course of the infection. There was no difference in recovery of smell and taste recovery between CTC, ward and ICU patients. 87.2% of the patients reported to have recovered from their smell and taste dysfunctions after 4 months. Parosmia after recovery of loss of smell has been reported by 13% of the patients. Conclusion: After 4 months, 87% of the patients with COVID-19 infection had recovered from their smell and taste loss. The smell dysfunction was related to the clinical course of the disease but it seems that there is no difference in recovery time of smell dysfunction between patients with severe and critical course disease.