Abstract
BackgroundPersistent olfactory dysfunction is a significant complication of SARS-CoV-2 infection. Olfactory training involving aromatic oils has been recommended to improve olfactory recovery, but quantitative data are missing.ObjectiveWe aimed to quantify the benefit of olfactory training and visual stimulation assisted by a dedicated web application for patients who experienced olfactory dysfunction for ≥1 month.MethodsWe performed an observational, real-life, data-based study on a cohort of patients who experienced at least 1 month of persistent olfactory dysfunction between January 30 and March 26, 2021. An analysis was performed after a mean olfactory training time of 4 weeks, and at least 500 patients were assessable for primary outcome assessment. Participants exposed themselves twice daily to odors from 4 high-concentration oils and visual stimulation assisted by a dedicated web application. Improvement was defined as a 2-point increase on a 10-point, self-assessed olfactory visual analogue scale.ResultsIn total, 548 patients were assessable for primary outcome assessment. The mean baseline, self-assessed olfactory score was 1.9 (SD 1.7), and this increased to 4.6 (SD 2.8) after a mean olfactory training time of 27.7 days (SD 17.2). Olfactory training was associated with at least a 2-point increase in 64.2% (352/548) of patients. The rate of patients’ olfactory improvement was higher for patients who trained for more than 28 days than that rate for patients who trained for less than 28 days (73.3% vs 59%; P=.002). The time to olfactory improvement was 8 days faster for patients with hyposmia compared to the time to improvement for patients with anosmia (P<.001). This benefit was observed regardless of the duration of the olfactory dysfunction.ConclusionsOlfactory training and visual stimulation assisted by a dedicated web application was associated with significant improvement in olfaction, especially after 28 days of olfactory training.
Highlights
Anosmia is a frequent symptom of SARS-CoV-2 infection, and its duration is usually less than 2 weeks before recovery [1,2,3]
After 18 weeks of olfactory training, olfactory function improved in 63% of patients who experienced olfactory dysfunction for a duration of less than 12 months and used high-concentration oils, whereas olfactory function improved in 19% of patients in the control group who used low-concentration oils
In order to quantitatively study the time course of olfactory scores during olfactory training in real life, we developed a web application dedicated to olfactory training and visual stimulations as well as the self-assessment and follow-up of olfactory scores
Summary
Anosmia is a frequent symptom of SARS-CoV-2 infection, and its duration is usually less than 2 weeks before recovery [1,2,3]. One treatment option that is recommended for persistent olfactory dysfunction is daily olfactory training involving high-concentration aromatic oils [7]. This showed significant results in treating postinfectious olfactory loss in a randomized, controlled, multicenter study [8]. In this trial, after 18 weeks of olfactory training, olfactory function improved in 63% of patients who experienced olfactory dysfunction for a duration of less than 12 months and used high-concentration oils, whereas olfactory function improved in 19% of patients in the control group who used low-concentration oils. Olfactory training involving aromatic oils has been recommended to improve olfactory recovery, but quantitative data are missing
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
