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Olfactory and Gustatory Dysfunctions in COVID-19 Patients: From a Different Perspective
Burcu Polat1, Nesrin Helvaci Yilmaz1, Gökhan Altin2
1Department of Neurology.
The Journal of Craniofacial Surgery
|January 11, 2021
Summary
About half of COVID-19 patients experienced smell or taste loss, with milder cases showing more frequent olfactory dysfunction. Early identification of these sensory changes can help prevent disease spread.
Area of Science:
- Otorhinolaryngology
- Infectious Diseases
- Epidemiology
Background:
- Sensory disorders, including loss of smell and taste, have a highly variable prevalence (5%-98%) in COVID-19 patients.
- These chemosensory dysfunctions are now recognized as key indicators of coronavirus disease 2019 (COVID-19) infection by the global scientific community.
Purpose of the Study:
- To investigate the prevalence and characteristics of smell and taste loss in outpatients and hospitalized patients with confirmed COVID-19.
- To analyze the correlation between chemosensory deficits and disease severity, patient demographics, and COVID-19 infection.
Main Methods:
- A cohort of 217 patients with laboratory-confirmed COVID-19 (positive PCR test) were enrolled.
- Patients with pre-existing sinonasal conditions or other respiratory infections were excluded.
- A structured questionnaire assessed changes in smell and taste, with symptom severity classified.
Main Results:
- Olfactory dysfunction was observed in 46.1% of patients, with 33.2% experiencing anosmia (complete loss of smell).
- Gustatory dysfunction affected 50.2% of patients, with ageusia (complete loss of taste) being the most common symptom.
- Anosmia was more prevalent in outpatients (P = 0.038), and chemosensory symptoms were reported more frequently by women (P = 0.009). No correlation was found with age.
Conclusions:
- Approximately half of the studied COVID-19 patients exhibited olfactory and/or gustatory deficits, with smell loss being more common in milder cases.
- Sudden, isolated smell or taste loss can occur in otherwise asymptomatic COVID-19 individuals.
- Prompt identification and isolation of individuals with these sensory symptoms are recommended to curb community transmission of COVID-19.
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