COVID-19-Induced Anosmia and Ageusia Are Associated With Younger Age and Lower Blood Eosinophil Counts

Background Anosmia and ageusia are symptoms commonly associated with COVID-19, but the relationship with disease severity, onset and recovery are unclear. Objective To examine factors associated with anosmia and ageusia and the recovery from these symptoms in an ethnically diverse cohort. Methods Individuals tested for SARS-CoV-2 between March and April 2020 were eligible for the study. Randomly selected participants answered a telephone questionnaire on COVID-19 symptoms with a focus on anosmia and ageusia. Additionally, relevant past medical history and data on the COVID-19 clinical course were obtained from electronic medical records. 486 patients were in the COVID-19 group and 103 were COVID-19-negative. Results Patients who were younger were more likely to report anosmia and/or ageusia (odds ratio (OR) for anosmia per 1-year increase in age: 0 center dot 98, 95%CI:0-97-0 center dot 99, p = 0 center dot 003; for ageusia: 0 center dot 98, 95%CI:0 center dot 97-0 center dot 99, p = 0 center dot 005) as were patients with lower eosinophil counts (OR for anosmia per 0.1-K/mu L increase in eosinophils: 0 center dot 02, 95%CI:0 center dot 001-0 center dot 46, p = 0 center dot 01, for ageusia 0 center dot 10, 95%CI:0 center dot 01-0 center dot 97, p = 0 center dot 047). Male gender was independently associated with a lower probability of ageusia (OR:0 center dot 56, 95%CI:0 center dot 38-0 center dot 82, p = 0 center dot 003) and earlier sense of taste recovery (HR:1 center dot 44, 95%CI:1 center dot 05-1 center dot 98, p = 0 center dot 02). Latinos showed earlier sense of taste recovery than white patients (HR:1 center dot 82, 95%CI:1 center dot 05-3 center dot 18, p = 0 center dot 03). Conclusion Anosmia and ageusia were more common among younger patients and those with lower blood eosinophil counts. Ageusia was less commonly reported among men, and time to taste recovery was earlier among both men and Latinos.