UCSF

Objective

To identify differentiation features of chemosensory dysfunction in COVID-19 infection and their primary drivers.

Study design

Cross-sectional cohort comparison.

Methods

A national anonymous survey was used to query participants regarding nasal symptoms and chemosensory dysfunction including sensitivity levels, and presence or absence of distortions and phantoms within the 6-week time window surrounding their COVID-19 testing and survey completion.

Results

Three-hundred and sixty-four respondents who reported COVID-19 positive (COVID+; n = 176) or COVID-19 negative (COVID-; n = 188) test results completed the survey. The COVID+ cohort had higher occurrence rates for: (a) chemosensory sensitivity impairments (67.0% vs 30.3%; P < .01), where the rate of complete loss of smell (anosmia) or taste (ageusia) was higher (35.8% vs 4.8%; P < .01), and (b) chemosensory distortions (39.8% vs 19.1%; P < .01), where the rate of anosmia or ageusia with distortions was also higher in the COVID+ cohort (19.9% vs 2.7%; P < .01). Occurrence rates in the two cohorts were similar for chemosensory phantoms (COVID+ 17.0%, COVID- 18.6%; P = .70) and nasal discharge or stuffiness in the presence of sensitivity impairment (COVID+ 63.6%, COVID- 52.6%; P = .17).

Conclusion

Chemosensory dysfunction in COVID-19 is associated with higher rates of smell or taste sensitivity impairments and distortions. Higher rates of anosmia and ageusia drive these key findings. Chemosensory phantoms and nasal symptoms in the presence of sensitivity impairment occur at rates that should demand clinical attention, but they do not appear to be specific to COVID-19 positivity.

Level of evidence

2b.