Increased Olfactory Scores Without Improved Quality of Life Among COVID-19 Long Haulers

Introduction: This study compares the severity of residual smell loss after recovery from COVID-19 and its quality-of-life effects on patients to other non-COVID-19 smell loss etiologies.

Methods: The Questionnaire of Olfactory Disorders Negative Statements (QOD-NS), the University of Pennsylvania Smell identification Tests (UPSIT), and the Sino-nasal Outcome Test (SNOT-22) were administered to patients presenting to outpatient otolaryngology clinics from 1/1/2022-5/5/22 with complaints of smell and/or taste disturbances. An exploratory retrospective chart review was performed for patients identified to have smell or taste loss by ICD-10 codes and who completed the questionnaires. Subjects were divided into two cohorts based on self-reported COVID-19 infection: COVID-19 and non-COVID-19. The COVID-19 cohort includes patients with a self-reported infection more than 35 days before presentation. Paired t-test was used to assess change in total scores and chi-square analysis was employed to compare group demographics.

Results: 37 COVID-19 and 45 non-COVID-19 patients met inclusion criteria. On average, COVID-19 patients presented after 278 days of altered smell. The COVID-19 cohort was less likely to suffer co-morbidities such as seasonal allergies (p < .003), asthma (p < .003), or chronic rhinitis (p < .003) and more likely to report parosmia (p < 0.001), decreased or altered taste (p < 0.001), and lower SNOT-22 scores (p < .05) indicating fewer nasal symptoms. COVID-19 patients had statistically higher UPSIT scores and were less likely to be classified in the total anosmia or severe microsomia UPSIT category (p=0.011). There was no statistical difference in total QOD-NS scores between groups.

Conclusions: COVID-19 patients have better smell after infection recovery as compared to patients with non-COVID smell loss etiologies; however, their overall quality of life is equally diminished. Although more investigation is needed, we believe this likely attributable to our finding of increased parosmia and altered taste among COVID-19 patients, which significantly impact quality of life.