Acta Scientific Otolaryngology (ASOL) (ISSN: 2582-5550)

Research Article Volume 4 Issue 7

Characteristic Features of Olfactory and Gustatory Dysfunctions of COVID-19 in Japanese Population

Katsuhisa Ikeda*, Kumiko Tanaka, Shinpei Arai, Nanae Yoshii and Ayako Inoshita

Department of Otorhinolaryngology, Juntendo University, Faculty of Medicine, Tokyo, Japan

*Corresponding Author: Katsuhisa Ikeda, Department of Otorhinolaryngology, Juntendo University, Faculty of Medicine, Tokyo, Japan.

Received: May 07, 2022; Published: June 17, 2022


Purpose: Chemosensory dysfunctions have been widely known as frequent and early symptoms of COVID-19. However, the underlying mechanisms of gustatory dysfunction associated with COVID-19 remain controversial. We aimed to reveal the dependency of taste impairment on smell function.

Materials and Methods: Olfactory and gustatory functions were subjectively and objectively examined in 54 COVID-19 patients.

Results: There were 5 patients with isolated subjective gustatory dysfunction and 4 patients with continuing smell dysfunction but resumed taste function, implying smell-independent gustatory dysfunction. Two patients with combined subjective dysfunctions showed objective smell dysfunction and normal objective taste function, suggesting a smell-dependent gustatory event. Olfactory and gustatory dysfunctions were subjectively found in 37.0 and 40.7%, respectively. Smell loss was objectively observed in 64.3% over 65 years, which was significantly greater than those (25.6%) of below 65 years. There was a significant difference in the mean open essence score between those under and those over 65 years.

Conclusion: Gustatory dysfunction is induced by both mechanisms of smell-independent and -dependent fashions in COVID-19 infection. The prevalence of olfactory and gustatory dysfunctions in Japanese corresponded to those of the countries with Caucasians rather than East Asians. A significant increase of objective olfactory dysfunction was recognized in the aged patients older than 65 years.

Keywords: COVID-19, olfactory dysfunction, gustatory function, objective test, smell-dependency


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Citation: Katsuhisa Ikeda., et al. “Characteristic Features of Olfactory and Gustatory Dysfunctions of COVID-19 in Japanese Population".Acta Scientific Otolaryngology 4.7 (2022): 59-64.


Copyright: © 2022 Katsuhisa Ikeda., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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