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Olfactory and gustatory dysfunction in COVID-19 patients: A meta-analysis study.
Bahareh Hajikhani1, Tess Calcagno2, Mohammad Javad Nasiri1
1Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Physiological Reports
|September 25, 2020
Summary
COVID-19 frequently causes smell and taste loss. This meta-analysis found nearly half of patients experienced taste impairment and over 60% had olfactory dysfunction, highlighting these as key symptoms.
Area of Science:
- Infectious Diseases
- Epidemiology
- Otolaryngology
Background:
- The novel coronavirus (COVID-19) pandemic presents significant global health challenges.
- Understanding the clinical manifestations of COVID-19 is crucial for effective patient management.
- Olfactory and gustatory dysfunctions are reported symptoms in COVID-19 patients.
Purpose of the Study:
- To conduct a large-scale meta-analysis to determine the prevalence of olfactory and gustatory dysfunction in COVID-19 patients.
- To summarize and characterize the clinical course of COVID-19, focusing on sensory impairments.
Main Methods:
- Searched major databases (PubMed/Medline, Embase, Web of Sciences) for relevant studies published up to April 30, 2020.
- Included studies reporting olfactory and/or gustatory disorders in confirmed COVID-19 cases; excluded reviews and meta-analyses.
- Assessed study quality using Joanna Briggs Institute checklists and performed data extraction by multiple observers.
- Calculated pooled frequencies of taste and smell disorders using a random-effects model with 95% confidence intervals.
Main Results:
- Analyzed 15 studies comprising 3,739 participants with confirmed COVID-19.
- Estimated prevalence of taste disorder was 49.0% (95% CI 34.0-64.0) and olfactory disorder was 61.0% (95% CI 44.0%-75.0%).
- High heterogeneity (I2: 96%) was observed for taste disorder prevalence.
Conclusions:
- COVID-19 is associated with high rates of taste (49.0%) and smell (61.0%) disorders.
- These findings emphasize that olfactory and gustatory dysfunction should be routinely considered in the assessment of COVID-19 infection.
- The results strengthen the evidence base for sensory loss as a significant clinical feature of COVID-19.
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