Anosmia and dysgeusia in COVID-19: A systematic review

Carrillo Larco, Rodrigo Martín; Altez-Fernandez, C.

dc.contributor.author	Carrillo Larco, Rodrigo Martín
dc.contributor.author	Altez-Fernandez, C.
dc.date.accessioned	2020-12-14T16:06:13Z
dc.date.available	2020-12-14T16:06:13Z
dc.date.issued	2020
dc.identifier.uri	https://hdl.handle.net/20.500.12866/8681
dc.description.abstract	Background: This systematic review had three aims: i) to determine the frequency of anosmia (or other smell disorders) and dysgeusia (or other taste disorders) in COVID-19 patients; ii) to determine whether anosmia or dysgeusia are independently associated with COVID-19 diagnosis; and iii) to determine whether anosmia or dysgeusia are prognostic factors for impaired outcomes among COVID-19 patients. Methods: On April 20 th, 2020, we search MEDLINE, Embase, Global Health, Scopus, Web of Science and MedXriv. We used terms related to COVID-19, smell and taste disorders. We selected case series, cross-sectional, case-control and cohort studies. We included studies with COVID-19 patients describing their symptoms; studies that compared smell and taste disorders between COVID-19 patients and otherwise healthy subjects; and studies comparing smell and taste disorders between COVID-19 severe and mild/moderate cases. Because of methodological heterogeneity and the limited number of results, a qualitative synthesis is presented. Results: From 31 reports, we selected six (n=2,757). Six studies reported the proportion of smell and taste disorders among COVID-19 patients. Two reports studied whether smell and taste disorders were independently associated with COVID-19 diagnosis. No reports studied the association with impaired outcomes among COVID-19 patients. The frequency of anosmia ranged between 22%-68%. The definition of taste disorders varied greatly, with dysgeusia present in 33% and ageusia in 20%. People who reported loss of smell and taste had six-fold higher odds of being COVID-19 positive; similarly, anosmia and ageusia were associated with 10-fold higher odds of COVID-19 diagnosis. Conclusions: The frequency of smell and taste disorders is as high as other symptoms, thus, at least anosmia for which the definition was more consistent, could be included in lists of COVID-19 symptoms. Although there is promising evidence, it is premature to conclude that smell and taste disorders are strongly associated with COVID-19 diagnosis.	en_US
dc.language.iso	eng
dc.publisher	F1000 Research
dc.relation.ispartofseries	Wellcome Open Research
dc.rights	info:eu-repo/semantics/restrictedAccess
dc.rights.uri	https://creativecommons.org/licenses/by-nc-nd/4.0/deed.es
dc.subject	COVID-19	en_US
dc.subject	Smell disorders	en_US
dc.subject	taste disorders	en_US
dc.subject	neurological symptoms	en_US
dc.title	Anosmia and dysgeusia in COVID-19: A systematic review	en_US
dc.type	info:eu-repo/semantics/review
dc.identifier.doi	https://doi.org/10.12688/wellcomeopenres.15917.1
dc.subject.ocde	https://purl.org/pe-repo/ocde/ford#1.06.03
dc.subject.ocde	https://purl.org/pe-repo/ocde/ford#3.00.00
dc.relation.issn	2398-502X