Modified Olfactory Training Is an Effective Treatment Method for COVID‐19 Induced Parosmia

Abstract

Objectives Coronavirus disease (COVID‐19) infection often causes olfactory dysfunction and parosmia may occur in some patients with olfactory dysfunction. In this study, we retrospectively investigated the effectiveness of modified olfactory training (MOT) for the treatment of COVID‐19‐induced parosmia. Study Design This study presents results of MOT performed with 12 odors for 36 weeks in patients with olfactory dysfunction following COVID‐19 infection. A total of 75 participants were included in the study (mean age 33 years, range 16–60 years). Methods The patients were separated into two groups: 1) Treatment group consisted of parosmia patients who received MOT with three sets of four different odors sequentially. 2) Control group consisted of parosmia patients who did not perform any olfactory training. Both groups were matched for age and sex distribution of participants. TDI scores were compared at the time of application and at the end of the 9th month by the Sniffin' Sticks Test. The results of the 0th and 9th months were recorded by applying the parosmia assessment scale to both groups. The results were analyzed statistically, and p < 0.05 was considered significant. Results When the treatment group and the control group were compared, a significant improvement was observed in both groups at the third, sixth, and ninth month, however the improvement in the treatment group was found to be better than in the control group ( P < .001). Extending the treatment from 6 to 9 months in the treatment group was found to be effective in mitigating parosmia complaints and improving discrimination scores ( P < .001). Conclusion This study has shown that modified olfactory training is effective in the treatment of parosmia following COVID‐19 infection. Level of Evidence 3 Laryngoscope , 2022

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19 related olfactory disorders

“…It also supports the use of SCENTinel 1.1 as a tool to help detect and monitor sudden loss of smell, which is a symptom of COVID-19 (5,55), as well as parosmia, an evolving symptom of COVID-19 (31,36,37). Early diagnosis of olfactory impairment is critical for establishing successful outcomes to treatment regimes like olfactory training (56) which has recently shown effectiveness with patients with parosmia (57).…”

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“…51 OT is maximally efficacious when started as soon as possible to the onset of smell loss, when performed for 9 months, and when 12 essential oils are rotated to increase novelty—the introduction of additional essential oil scents has been termed Modified Olfactory Training. 52 Altundag et al 53 showed that this regimen also works for COVID-19-induced parosmia, significantly improving parosmia and quantitative olfaction as compared to controls ( P = .001 and P < .001, respectively).…”

SARS-CoV-2 Infection (COVID-19) and Rhinologic Manifestation: Narrative Review

“…Several studies have reported the effects of olfactory training in patients with COVID-19-associated olfactory dysfunction and that subjective and objective olfactory functions were significantly improved after olfactory training [ 23 , 24 ]. Denis et al performed olfactory training with a mean visual stimulation duration of 4 weeks in 548 patients with COVID-19-associated olfactory dysfunction.…”

“…Altundag et al performed modified olfactory training using 12 odorants during a 36-week period on 75 patients with COVID-19-associated parosmia, and reported a significant improvement in olfactory function in both treatment and non-treatment groups at the third, sixth, and ninth months. However, the degree of improvement was significantly higher in the treatment group than in the non-treatment group [ 24 ]. The authors also published an article about the effects of olfactory training in patients with persistent olfactory dysfunction for about 3 months.…”