Smell and Taste in Severe CoViD-19: Self-Reported vs. Testing

Area of Science:

• Neurology
• Infectious Diseases
• Otolaryngology

Background:

• Loss of smell and taste are prominent symptoms of COVID-19.
• Assessing these impairments is crucial for diagnosis and understanding viral pathogenesis.
• The specificity of these symptoms as a biomarker for central nervous system involvement is of great interest.

Purpose of the Study:

• To objectively evaluate the severity of olfactory and gustatory impairment in severe COVID-19 patients.
• To compare self-reported symptoms with objective testing results.
• To explore the correlation between smell/taste dysfunction and other COVID-19 symptoms, age, sex, and hospitalization duration.

Main Methods:

• Objective testing of smell and taste function in severe COVID-19 patients.
• Statistical analysis to compare self-reported deficits with objective findings.
• Correlation analysis between olfactory impairment severity and clinical parameters like symptom onset and hospitalization.

Main Results:

• A significant discrepancy exists between self-reported and objectively tested smell and taste abilities (p < 0.001).
• Objective testing revealed hyposmia (34%), severe hyposmia (48%), and anosmia (13%) in COVID-19 patients.
• 95% of patients exhibited smell dysfunction, while 47% had taste dysfunction; olfactory impairment correlated with symptom onset and hospitalization (p < 0.05).

Conclusions:

• Objective smell testing is essential, as self-reporting underestimates the prevalence and severity of olfactory dysfunction in COVID-19.
• Severe olfactory impairment in COVID-19 correlates with infection severity and may indicate neurological damage.
• Smell test assessment could serve as a potential screening tool for COVID-19, guiding testing, quarantine, and evaluation of neurological impact.