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Author Spotlight: Assessing the Olfactory Effects of Airborne Pollutants — Buried Food and Social Odor Tests

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Persistent olfactory dysfunction in mild COVID-19 patients: A descriptive study of the characteristics and

David Dylan García-Meléndez¹, María Isabel Morales-Casado¹, Pilar Quintana Castro¹

¹Hospital Universitario de Toledo, Av. Río Guadiana, 45007 Toledo, Spain.

Medicina Clinica (English Ed.)

|May 2, 2023

Abstract

Introduction:

Post-COVID olfactory dysfunction continues to be studied due to the controversy of the mechanisms involved. The aim was to investigate the olfactory dysfunctions in association with other post-COVID symptoms.

Material And Methods:

Observational, descriptive and single-center study. The patients had confirmed mild COVID-19 and subjective olfactory dysfunction of more than a month of evolution, which was assessed by Sniffin' Sticks Olfactory Test.

Results:

A total of 86 patients participated. The mean age was 37.2 years (SD 9.82). 70.9% reported parosmia and 46.5% symptoms of brain fog. A pathological test result was obtained in 72.1% of the participants. The most failed pen was 11 (apple) in 76.7%. Anosmia of pen 15 (anise) was reported more frequently in 24.4% and cacosmia of pen 9 (garlic) in 27.9%. We observed a significant association between patients who reported parosmias and brain fog (RR 2.18; p = 0.018), also between parosmia and phantosmia (RR 6.042; p < 0.001).

Conclusion:

There is some pathological selectivity for certain test pens, a higher prevalence of cognitive symptoms and many patients with combined parosmia and brain fog.

Keywords:

Anosmia Brain fog COVID-19 Long COVID Olfactory dysfunction Parosmia

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