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. 2023 Feb;280(2):757-763.
doi: 10.1007/s00405-022-07570-w. Epub 2022 Jul 29.

Effects of classical olfactory training in patients with COVID-19-related persistent loss of smell

Atılay Yaylacı  1 , Emel Azak  2 , Alperen Önal  3 , Doğukaan Ruhi Aktürk  3 , Aynur Karadenizli  2
Affiliations

Effects of classical olfactory training in patients with COVID-19-related persistent loss of smell

Atılay Yaylacı et al. Eur Arch Otorhinolaryngol. 2023 Feb.

Abstract

Purpose: The management of post-COVID-19 persistent olfactory dysfunction (OD) is uncertain. Currently, olfactory training is the only evidence-based therapy for post-viral OD. In this study, we evaluated the effectiveness of classical olfactory training (COT) in the treatment of post-COVID-19 persistent OD.

Materials and methods: Patients with persistent OD after COVID-19 were assessed using the Sniffin' Sticks test. Fifty-one patients were then divided into two groups based on personal preference: the COT group (n = 31) included subjects who performed COT over 12 weeks, and the control group (n = 20) included subjects who did not receive any treatment. After the exclusion of eight patients, the olfactory performances of 43 patients were re-evaluated and compared to the baseline values.

Results: A significantly higher proportion of patients in the COT group improved their olfactory scores above the clinically important difference compared to the control group (40% versus 6%) (p = 0.014). The subjective smell improvement by COT was independent of age, gender, OD duration, presence of parosmia, or the initial olfactory score (all p > 0.05).

Conclusion: Twelve weeks of COT appears to increase the olfactory sensitivity in patients with persistent OD following COVID-19.

Keywords: Anosmia; COVID-19; Hyposmia; Loss of smell; Olfactory dysfunction; Olfactory training.

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Conflict of interest statement

The authors have no conflict of interest to declare.

Figures

Fig. 1
Fig. 1
Mean threshold (T), discrimination (D), identification (I), and composite TDI scores at the beginning and twelfth weeks for the control group (no training) and the COT (classical olfactory training) group
Fig. 2
Fig. 2
Boxplot indicates the difference in the mean threshold–discrimination–identification (TDI) score between the end of the twelfth week and the start of the study for the control (no training) and COT (classical olfactory training) groups
See this image and copyright information in PMC

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