Treatment of Postviral Olfactory Dysfunction

Study Overview
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Brief Summary
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A decreased sense of smell (hyposmia) is often caused by viral infections, such as COVID-19. Today, the only recommended treatment for hyposmia is olfactory training, a time consuming method with limitations in terms of both compliance and effect. The aim of this study is therefore to evaluate, as well as optimize, a new treatment method for olfactory loss. Hyposmic participants will be recruited and randomized into two different treatment conditions. One group will do regular olfactory training and the other will do passive olfactory training with scented nose plugs. The training will be conducted in the home of the individual monday through friday for two consecutive months. Subjective and objectvie measures of olfactory problems will be assessed before and after treatment, as well as subjective measures related to quality of live and genereal wellbeing.

Official Title
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Treatment of Postviral Olfactory Dysfunction

Conditions
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Hyposmia

Intervention / Treatment
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* Device: Nose plug
* Other: Regular olfactory training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 - 65 years old Physically and cognitively capable of participating in the study Having appropriate olfactory screening test scores (hyposmic) Exclusion Criteria: Anosmics Individuals with other diagnoses that could affect the study results

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Olfactory training with nose plugs<br>Participants will complete olfactory training with scented nose plugs. | Device: Nose plug<br>* Participants will complete olfactory training with scented nose plugs.<br>|
| Active Comparator: Olfactory training with household odors<br>Participants will complete olfactory training with odors found in their household. | Other: Regular olfactory training<br>* Participants will complete olfactory training with regular odors found in their home.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Objective olfactory function | Does the use of scented nose plugs increase the effect of olfactory training on objective olfactory function compared to regular olfactory training? For this outcome, we will use the standardized Sniffin' Sticks test to assess olfactory function. | 2 months | 
| Subjective symptoms and social/emotional consequences | Does the use of scented nose plugs increase the effect of olfactory training on subjective symptoms and social/emotional consequences compared to regular olfactory training? For this outcome, we will use the Sino-Nasal Outcome Test (SNOT). | 2 months | 
| Subjective health | Does the use of scented nose plugs increase the effect of olfactory training on subjective health compared to regular olfactory training? For this outcome, we will use the Self-Rated Health 5 measure and SF-36. | 2 months | 
| Subjective olfactory function | Does the use of scented nose plugs increase the effect of olfactory training on subjective olfactory function compared to regular olfactory training? For this outcome, we will use the Self-Reported Mini Olfactory Questionnaire. | 2 months | 
| Subjective degree of suffering from olfactory impairment | Does the use of scented nose plugs increase the effect of olfactory training on subjective degree of suffering from olfactory impairment compared to regular olfactory training? For this outcome, we will use the Questionnaire of Olfactory Disorders - Negative Statements. | 2 months | 
| Subjective parosmia | Does the use of scented nose plugs increase the effect of olfactory training on subjective parosmia compared to regular olfactory training? For this outcome, we will use the Landis parosmia questionnaire. | 2 months | 
| Subjective depressive symptoms | Does the use of scented nose plugs increase the effect of olfactory training on depressive symptoms compared to regular olfactory training? For this outcome, we will use the Beck Depression Inventory (BDI). | 2 months | 
| Subjective general wellbeing | Does the use of scented nose plugs increase the effect of olfactory training on depressive symptoms compared to regular olfactory training? For this outcome, we will use the General Well Being Schedule. | 2 months | 
| Compliance | Does the use of scented nose plugs increase the compliance of olfactory training compared to regular olfactory training? For this outcome, we will use questions asking the participants about their experience during the olfactory training, specifically targeting their compliance, such as how often they actually completed the olfactory training and how often they forgot to. | 2 months |