Prevalence and outcomes of olfactory and gustatory dysfunctions in hospitalized SARS-CoV-2-infected patients

Abstract
Background
The prevalence of olfactory/gustatory dysfunctions among hospitalized SARS-CoV-2-infected patients is highly variable between different studies, ranging from 5.6% in the Asian population to 86% in the European population. The study aimed to detect the prevalence and the recovery of olfactory/gustatory dysfunctions in hospitalized SARS-CoV-2-infected patients in an Egyptian tertiary care center. A total of 579 hospitalized patients were enrolled. Demographic data as well as upper respiratory tract symptoms including olfactory/gustatory dysfunctions and other risk factors were documented. Then the recovery of olfactory/gustatory dysfunctions after 6 months was followed up.

Results
50.6% had olfactory/gustatory dysfunctions (24.2% had a total smell and taste loss). A logistic regression analysis revealed a statistical significance between olfactory/gustatory dysfunctions and female gender and presence. Most patients (88.4%) reported partial or complete recovery during the 6 months (28.0% and 60.4%, respectively), while 11.6% of patients did not recover. The median time to start recovery was 3 days, and the median time to the best recovery was 22 days.

Conclusions
Olfactory/gustatory dysfunctions should be recognized for early detection of COVID-19 infection. Most recovery of olfactory/gustatory dysfunction in COVID-19 infection starts within 3 days and reaches the best recovery within 19 to 24 days. Female gender and the presence of general symptoms are associated with olfactory/gustatory dysfunctions in the hospitalized COVID-19 patients.