COVID-19-related chemosensory changes: Findings from a prospective national database

The aim of this study was to review findings from a large prospective national database of chemosensory disturbances associated with coronavirus disease 2019 (COVID-19) infection.

The Virginia Commonwealth University Smell and Taste Center national database of COVID-19 chemosensory disturbances.

A series of online surveys, first opened on April 10, 2020, was made accessible nationwide to any adult with sudden chemosensory dysfunction since January 2020. Participants received subsequent follow-up surveys 14 days, 1 month, 3 months, and 6 months after enrollment. An additional survey was sent to all participants on May 28, 2022 to assess long-term outcomes. Information pertaining to demographics, symptoms, comorbidities, treatments, and life impact was collected.

Of 363 participants who reported complete smell recovery, 51.2% recovered within 1 month, 70% within 3 months, and 79% within 6 months, while 8.8% took over 1 year to completely recover. Among all participants, 7.5% had no smell recovery. Positive predictors of recovery included age <40, male gender, and the presence of nasal congestion. Negative predictors included difficulty breathing and prior head injury. Many participants reported a decrease in quality of life and the presence of potential safety hazards associated with decreased smell loss.

Most subjects with COVID-19-related chemosensory dysfunction recover, with the majority noting complete recovery within weeks of infection. Those aged over 40 years and female gender were associated with lower rates of recovery. A considerable number of participants reported significant impact on quality of life and safety.