Clinical, Prognostic, and Predictive Value of Olfactory Dysfunction for COVID-19: A Prospective Controlled Study

Area of Science:

• Otorhinolaryngology
• Infectious Diseases
• Pulmonology

Background:

• Olfactory dysfunction is a recognized symptom of COVID-19.
• The prognostic and predictive significance of olfactory dysfunction in COVID-19 requires further investigation.

Purpose of the Study:

• To evaluate the impact of olfactory dysfunction on COVID-19 course and severity.
• To assess the prognostic and predictive value of olfactory dysfunction for COVID-19.

Main Methods:

• Prospective case-control study involving PCR-positive patients, symptomatic PCR-negative patients, and healthy controls.
• Olfactory function assessed using the Sniffin' Sticks identification (SS-ID) test and visual analog scale (VAS-smell).
• Clinicodemographic data, inflammatory markers, and CT findings were recorded; disease progression and ICU admission were tracked.

Main Results:

• Mean SS-ID scores were significantly lower in PCR-positive patients compared to negative and control groups.
• PCR-positive patients exhibited lower VAS-smell scores and higher prevalence of anosmia.
• Olfactory dysfunction severity did not correlate with inflammatory markers, CT stage, disease progression, or ICU admission.

Conclusions:

• Objective and subjective olfactory dysfunction are present in PCR-positive COVID-19 patients.
• Olfactory dysfunction alone does not determine COVID-19 severity or prognosis.
• Olfactory dysfunction, particularly a low SS-ID score, shows potential in predicting COVID-19 positivity.