Chemosensory Dysfunction in Long-Term COVID-19 Assessed by Self-Reported and Direct Psychophysical Methods.

Area of Science:

• Neuroscience
• Otolaryngology
• Psychophysics

Background:

• Chemosensory dysfunction is a common post-COVID-19 symptom, with varying reported severity based on assessment methods.
• Discrepancies exist between self-reported and objectively measured chemosensory deficits in long COVID patients.

Purpose of the Study:

• To investigate smell, taste, and chemesthesis in long COVID patients using both self-report and direct psychophysical methods.
• To compare the agreement between different assessment tools for chemosensory function in COVID-19 survivors.
• To establish best practices for monitoring chemosensory dysfunction post-COVID-19.

Main Methods:

• Cross-sectional analysis of 208 Italian participants (133 COVID+, 75 COVID-) in a longitudinal study.
• Utilized the Smell and Taste Check (GCCR) for self-reports and direct intensity ratings of household items.
• Administered SCENTinel, a validated direct smell test, alongside other psychophysical measures.

Main Results:

• Strong association found between self-reported, unstandardized, and validated direct smell tests.
• SCENTinel performance significantly correlated with self-reported smell loss.
• Positive correlations observed between self-reports and direct taste/chemesthesis measures.
• Time since COVID-19 onset did not significantly impact chemosensory performance.

Conclusions:

• Confirms persistent impairment of smell, taste, and chemesthesis in long COVID patients.
• Demonstrates concordance between self-reported and direct psychophysical assessment methods for chemosensory function.
• Provides evidence supporting the use of combined assessment strategies for accurate evaluation of post-COVID-19 chemosensory deficits.