Smell and taste alterations in COVID‐19: a cross‐sectional analysis of different cohorts

Abstract

Background: Olfactory (OD) and gustatory (GD) dysfunction have been proven to be a typical symptom of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. However, their prevalence in different patient populations still needs to be clarified. Methods: A cross-sectional study was performed from March 27 to April 1, 2020, in Northern Italy. Physicians administered a survey-based questionnaire to SARS-CoV-2positive patients with the aim of assessing symptoms, focusing on OD and GD. Two groups were studied: group A, patients hospitalized at Azianda Socio Sanitaria Territoriale (ASST) Spedali Civili University Hospital of Brescia; and group B, home-quarantined subjects. Results: A total of 508 patients were enrolled: 295 in group A and 213 in group B. Mean age ± standard deviation (SD) was 55 ± 15 years; 56% were men. Overall, OD and GD were present in 56% (95% confidence interval [CI], 51% to 60%) and 63% (95% CI, 59% to 67%) of cases, respectively. In group A, the prevalence of OD and GD was 44% (95% CI, 38% to 50%) and 52% (95% CI, 46% to 58%), respectively. In group B, the prevalence of OD and GD was 72% (95% CI, 65% to 79%) and 79% (95% CI, 73% to 84%), respectively. In the entire cohort, total loss of olfaction and taste was reported in 64% and 60% of cases, respectively. OD and GD occurred as the first symptom in 10% and 11% of cases, respectively; in the remaining cases, they occurred a er a mean of 4 ± 3 days following the first symptom. At the time of the questionnaire, complete resolution of OD and GD was reported in 52% and 55% of cases, respectively (mean duration, 9 ± 5 days in both). Conclusion: OD and GD are more prevalent in homequarantined subjects, and they are independently associated with younger age and female gender. C 2020 ARS-AAOA, LLC.

Olfactory disorders in coronavirus disease 2019 patients: a systematic literature review

“…18,20,[24][25][26]29,32,34,37,[40][41][42][43][47][48][49][50][51][52][53][54][55][56][57][58][59] The remaining studies assessed olfactory ability through anamnestic data collection, simple surveys and/or structured, non-validated questionnaires (Table 4). 2,16,17,19,[21][22][23]27,28,30,31,33,35,36,38,39,[44][45][46]…”

“…61 Regarding the hospital setting, our review highlighted a lower prevalence of smell disorders in hospitalised patients compared with home-quarantined patients. Two studies focused specifically on this comparison, 2,35 emphasising a greater prevalence of the disorder in individuals with low-to-mild disease compared to those who needed hospital treatment. Once again, this difference could be related to greater attention devoted to olfactory impairment in patients in an overall better health condition.…”

COVID‐19 Viral Load in the Severity of and Recovery From Olfactory and Gustatory Dysfunction

“…However, the prevalence of olfactory and gustatory disturbance in our local COVID-19 cohort is consistent with the results of a metaanalysis of 10 large cohort studies of smell impairment and nine large cohort studies of taste impairment, respectively, which showed a prevalence of 52.5% and 43.93% of olfactory and gustatory dysfunction. 20 However, some individual cohorts display the opposite trend, with a higher prevalence of gustatory than olfactory impairment, 21,22 which cannot be explained solely by regional differences in viral load in the pharynx.…”

Olfactory and gustatory dysfunction in COVID‐19 patients: A meta‐analysis study

“…In fact, there are some reports that COVID-19 patients experience a period of anosmia and/or ageusia without any other symptoms (Hummel, Landis, & Huttenbrink, 2011;Karimi-Galougahi, Raad, & Mikaniki, 2020). Olfactory and taste dysfunction have very recently been reported to be higher in home-quarantined, young, and female patients (Paderno et al, 2020). Screening for loss of taste or smell in otherwise asymptomatic individuals may be an effective strategy to stop transmission early in the disease.…”