Clinical Features of Parosmia Associated With COVID-19 Infection

To characterize the clinical features, risk factors, symptom time-course, and quality of life implications for parosmia among coronavirus disease (COVID)-related olfactory dysfunction patients.

Individuals with olfactory dysfunction associated with laboratory-confirmed or clinically suspected COVID-19 infection were recruited from otolaryngology and primary care practices over a period from August 2020 to March 2021. Participants completed olfactory dysfunction and quality of life surveys.

A total of 148 (64.1%) of 231 respondents reported parosmia at some point. Parosmia developed within 1 week of any COVID-19 symptom onset in 25.4% of respondents, but more than 1 month after symptom onset in 43.4% of respondents. Parosmia was associated with significantly better quantitative olfactory scores on Brief Smell Identification Test (8.7 vs. 7.5, P = .006), but demonstrated worse quality of life scores, including modified brief Questionnaire of Olfactory Dysfunction-Negative Statements and Sino-Nasal Outcome Test-22 scores (12.1 vs. 8.5, P < .001; 26.2 vs. 23.2, P = .113). Participants who developed parosmia at any point were significantly younger and less likely to have history of chronic sinusitis than those who did not develop parosmia (40.2 vs. 44.9 years, P = .007; 7.2% vs. 0.7%, P = .006).

COVID-19-associated olfactory dysfunction is frequently linked with development of parosmia, which often presents either at onset of smell loss or in a delayed fashion. Despite better quantitative olfactory scores, respondents with parosmia report decreased quality of life. A majority of respondents with persistent parosmia have sought treatment.

3 Laryngoscope, 132:633-639, 2022.