Objective: To investigate prevalence and epidemiological and clinical factors associated with OD and GD in COVID-19 patients according to the disease severity. Study design: Cross-sectional study. Methods: A total of 2,579 patients with a positive diagnosis of COVID-19 were identified between March 22 and June 3, 2020 from 18 European hospitals. Epidemiological and clinical data were extracted. Otolaryngological symptoms, including OD and GD were collected through patient-reported outcome questionnaire and sniffin-sticks tests were carried out in a subset of patients. Results: A total of 2,579 patients were included, including 2,166 mild (84.0%), 144 moderate (5.6%) and 269 severe-to-critical (10.4%) patients. Mild patients presented an otolaryngological picture of the disease with OD, GD, nasal obstruction, rhinorrhea and sore throat as the most prevalent symptoms. The prevalence of subjective OD, GD were 73.7 and 46.8% and decrease with the severity of the disease. Females had higher prevalence of subjective OD and GD compared with males. Diabetes was associated with a higher risk to develop GD. Among the subset of patients who benefited from psychophysical olfactory evaluations, there were 75 anosmic, 43 hyposmic and 113 normosmic patients. The prevalence of anosmia significantly decreased with the severity of the disease. Anosmia or hyposmia were not associated with any nasal disorder, according to SNOT-22. Conclusion: OD and GD are more prevalent in patients with mild COVID-19 compared with individuals with moderate, severe or critical diseases. Females might have a higher risk of developing OD and GD compared with males.

Objective Olfactory Findings in Hospitalized Severe COVID-19 Patients.Jerome R. Lechien, MD, PhD, MS1-4, Morgane Ducarme, MD5, Sammy Place, MD6, Carlos M. Chiesa-Estomba, MD, MS1,7, Mohamad Khalife, MD1,8, Giacomo De Riu, MD9, Luigi Angelo Vaira, MD9, Christophe de Terwangne, MD10, Shahram Machayekhi, MD10, Arnaud Marchant, MD, PhD11, Fabrice Journe, PhD2*, Sven Saussez, MD, PhD1,2,4*