Recovery rate and factors associated with smell and taste disruption in patients with coronavirus disease 2019

Purpose: To determine the occurrence of olfactory and gustatory disruptions in COVID-19 patients, their association with demographic and clinical features and prognosis. Material and methods: This observational cohort study involved consecutively diagnosed COVID-19 patients tested between March the 3rd 2020 and March the 24th 2020, in a geographically defined cohort area. All COVID-19 patients were evaluated in a University Hospital. The primary outcome of interest is the prevalence of smell and taste alterations, factors associated and recovery rate. Univariate and multivariate analysis by logistic regression was performed to detect factors associated to these symptoms. Results: 151 patients were included and 99 (65.6%) reported olfactory or gustatory symptoms. Olfactory dysfunction was reported by 75 patients (49.7%). Isolated anosmia was found in 2 patients (1.3%). Gustatory dysfunction was reported by 91 patients (60.3%). Factors associated with higher prevalence of smell dysfunction included age, sex, and comorbidities. The time to smell disruption development was significantly shorter in mild to moderate patients than in severe patients (p = 0.043). In 85.3% of patients with smell disruption, the symptom had been resolved in the first 2 months. 14.7% of patients remained symptomatic after 3 months of follow-up. Conclusions: Olfactory and gustatory dysfunction was common in COVID-19 patients. Smell disruption has high recovery rate and was associated with age, sex, and clinical severity. It may be beneficial to investigate the appearance of taste and/or smell disruptions in individual patients, with respect to diagnosis and prognosis.

Automated summary

The study found that olfactory and gustatory dysfunction was common in COVID-19 patients, with associations to age, sex, and clinical severity. Smell disruption had a high recovery rate, with most patients experiencing symptom relief within two months, while around 15% remained symptomatic after three months of follow-up.