Olfactory and Gustatory Symptoms of Coronavirus Disease 2019: A Systematic Review and Meta-analysis

Abstract

Introduction: There is increasing anecdotal evidence that olfactory and gustatory dysfunction may be associated with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Aim: The aim of this systematic review and meta-analysis was to find the association of olfactory and gustatory symptoms with Coronavirus Disease-19 (COVID-19) and estimate their pooled prevalence. Materials and Methods: PubMed, Embase, EBSCO and Cochrane databases were searched for cross-sectional, cohort and case-control studies evaluating olfactory and gustatory symptoms in patients with COVID-19. The search terms included COVID-19, severe acute respiratory syndrome coronavirus-2, coronavirus, olfaction disorders, anosmia, hyposmia, dysgeusia and ageusia. Random effects model was used to calculate a pooled Odds Ratio (OR) and pooled prevalence. Results: Total 14 studies were included in qualitative synthesis and 13 studies were incorporated in quantitative synthesis, involving 3,125 patients. The pooled OR was 15.59 reflecting that smell and taste disorders were strongly associated with COVID-19. The pooled prevalence of olfactory and gustatory dysfunction was 56% and 44%, respectively. Conclusion: It can be concluded that there is a significant association between olfactory and gustatory symptoms and COVID-19. Majority of the studies support the use of these symptoms as screening tools for COVID-19.