Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024;86(3-4):107-117.
doi: 10.1159/000539378. Epub 2024 May 24.

Subjective versus Psychophysical Measures of Chemosensory Alterations following COVID-19

Brandon J Vilarello  1 , Patricia T Jacobson  2 , Clayton J Snyder  3 , Tse-Hwei Choo  3 , Liam W Gallagher  4 , Francesco F Caruana  4 , Jeremy P Tervo  4 , Joseph B Gary  4 , Tiana M Saak  4 , David A Gudis  4   2 , Paule V Joseph  5 , Terry E Goldberg  6 , Devangere P Devanand  4   6 , Jonathan B Overdevest  4   2
Affiliations

Subjective versus Psychophysical Measures of Chemosensory Alterations following COVID-19

Brandon J Vilarello et al. ORL J Otorhinolaryngol Relat Spec. 2024.

Abstract

Introduction: Olfactory dysfunction is a common symptom of COVID-19. However, subjective perception of olfactory function does not always correlate well with more objective measures. This study seeks to clarify associations between subjective and psychophysical measures of olfaction and gustation in patients with subjective chemosensory dysfunction following COVID-19.

Methods: Adults with persistent COVID-19-associated chemosensory disturbance were recruited for a prospective, longitudinal cohort study at a tertiary care institution. Participants provided subjective measures of olfactory and gustatory function and underwent psychophysical assessment using Sniffin' Sticks olfactory and Monell gustatory tests.

Results: Data analysis (n = 65) showed a statistically significant association between subjective and psychophysical measures of olfaction (p < 0.001). For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.11 (95% CI: 0.06, 0.16; p < 0.001) point increase in TDI score while adjusting for age at baseline assessment, sex, and follow-up time. For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.04 (95% CI: 0.02, 0.06; p < 0.001) point and 0.05 (95% CI: 0.03, 0.07; p < 0.001) point increase in discrimination and identification scores, respectively, when adjusting for age at baseline assessment, sex, and follow-up time.

Conclusion: Subjective olfaction shows a mild to moderate association with psychophysical measures, but it fails to comprehensively assess persistent COVID-19-associated chemosensory deficits. The lack of significant association between subjective olfaction and threshold limits the utility of subjective olfaction in tracking recovery. These findings support the push for more widespread psychophysical chemosensory testing.

Keywords: COVID-19; Gustation; Olfaction; Psychophysical testing.

PubMed Disclaimer

Conflict of interest statement

The authors have no conflicts of interest to declare.

Figures

Fig. 1.
Fig. 1.
Scatter plot, with regression line, for association between subjective olfaction and psychophysical olfaction (TDI score, p < 0.001).
Fig. 2.
Fig. 2.
Scatter plot, with regression line, for association between subjective olfaction and threshold score (not statistically significant).
Fig. 3.
Fig. 3.
Scatter plot, with regression line, for association between subjective olfaction and discrimination score (p < 0.001).
Fig. 4.
Fig. 4.
Scatter plot, with regression line, for association between subjective olfaction and identification score (p < 0.001).
See this image and copyright information in PMC

References

    1. Sudre CH, Murray B, Varsavsky T, Graham MS, Penfold RS, Bowyer RC, et al. Attributes and predictors of long COVID. Nat Med. 2021;27(4):626–31. - PMC - PubMed
    1. Lopez-Leon S, Wegman-Ostrosky T, Perelman C, Sepulveda R, Rebolledo PA, Cuapio A, et al. More than 50 long-term effects of COVID-19: a systematic review and meta-analysis. Sci Rep. 2021;11(1):16144. - PMC - PubMed
    1. Soriano JB, Murthy S, Marshall JC, Relan P, Diaz JV; WHO Clinical Case Definition Working Group on Post-COVID-19 Condition . A clinical case definition of post-COVID-19 condition by a Delphi consensus. Lancet Infect Dis. 2022;22(4):e102–7. - PMC - PubMed
    1. Ohla K, Veldhuizen MG, Green T, Hannum ME, Bakke AJ, Moein ST, et al. A follow-up on quantitative and qualitative olfactory dysfunction and other symptoms in patients recovering from COVID-19 smell loss. Rhinology. 2022;60(3):207–17. - PMC - PubMed
    1. Parma V, Ohla K, Veldhuizen MG, Niv MY, Kelly CE, Bakke AJ, et al. More than smell-COVID-19 is associated with severe impairment of smell, taste, and chemesthesis. Chem Senses. 2020;45(7):609–22. - PMC - PubMed

Publication types

MeSH terms