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The outcome of olfactory impairment in patients with otherwise paucisymptomatic coronavirus disease 2019 during the pandemic

Part of: JLO Coronavirus Collection

Published online by Cambridge University Press:  22 April 2021

M Jalessi ,
S H Bagheri ,
Z Azad ,
F D Firouzabadi ,
E Amini ,
R Alizadeh ,
S Chaibakhsh ,
B Ghalehbaghi ,
C Hopkins  and
M Farhadi
M Jalessi
Affiliation:
Skull Base Research Centre, Tehran, Iran
S H Bagheri
Affiliation:
ENT Department and Head and Neck Research Centre, Tehran, Iran
Z Azad*
Affiliation:
Skull Base Research Centre, Tehran, Iran
F D Firouzabadi
Affiliation:
ENT Department and Head and Neck Research Centre, Tehran, Iran
E Amini
Affiliation:
Skull Base Research Centre, Tehran, Iran
R Alizadeh
Affiliation:
ENT Department and Head and Neck Research Centre, Tehran, Iran
S Chaibakhsh
Affiliation:
Eye Research Centre, The Five Senses Health Institute, Hazrat Rasoul Hospital, Iran University of Medical Sciences, Tehran, Iran
B Ghalehbaghi
Affiliation:
ENT Department and Head and Neck Research Centre, Tehran, Iran
C Hopkins
Affiliation:
Guy's and St Thomas’ Hospital, King's College, London, UK
M Farhadi
Affiliation:
ENT Department and Head and Neck Research Centre, Tehran, Iran
*
Author for correspondence: Dr Zahra Azad, Skull Base Research Center, Hazrat Rasoul Hospital, Niayesh St, Sattarkhan Ave, Tehran1445613131, Iran E-mail: zahraazadmd@gmail.com Fax: +98 216 652 5329
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Abstract

Objective

This study aimed to measure the duration and recovery rate of olfactory loss in patients complaining of recent smell loss as their prominent symptom during the coronavirus disease 2019 outbreak.

Method

This was a prospective telephone follow-up observational study of 243 participants who completed an online survey that started on 12 March 2020.

Results

After a mean of 5.5 months from the loss of smell onset, 98.3 per cent of participants reported improvement with a 71.2 per cent complete recovery rate after a median of 21 days. The chance of complete recovery significantly decreased after 131 days from the onset of loss of smell (100 per cent sensitive and 97.7 per cent specific). Younger age and isolated smell loss were associated with a rapid recovery, whereas accompanying rhinological and gastrointestinal symptoms were associated with longer loss of smell duration.

Conclusion

Smell loss, occurring as a prominent symptom during the coronavirus disease 2019 pandemic, showed a favourable outcome. However, after 5.5 months from the onset, around 10 per cent of participants still complained of moderate or severe hyposmia.

Keywords

Olfactory DisordersSmellCOVID-19SARS-CoV-2Coronavirus
Type
Main Articles
Information
The Journal of Laryngology & Otology , Volume 135 , Issue 5 , May 2021 , pp. 426 - 435
Copyright
Copyright © The Author(s), 2021. Published by Cambridge University Press

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Footnotes

Dr Z Azad takes responsibility for the integrity of the content of the paper

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