NCT05384561

Brief Summary

Olfactory dysfunction is a defining symptom of COVID-19 infection. Studies have demonstrated improved olfaction in patients with post infectious olfactory dysfunction after an olfactory training (OT). The aim of this study is to assess the clinical outcomes of olfactory training (12 weeks) therapy in the treatment of persistent olfactory dysfunctions after COVID-19. Specially, we aim to compare the effectiveness of two different olfactory training (different odors). A group will train themselves with 4 scents (rose, orange, clove and eucalyptus) and another group with 4 different scents (cheese, coffee, strawberries and lemon). Olfaction sensory evaluation will be performed by using different olfaction tests (Sniffin' Sticks and UPSIT) and complete questionnaires to assess olfactory perception and particularly parosmia and phantosmia.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
70

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started May 2022

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 19, 2022

Completed
1 day until next milestone

First Posted

Study publicly available on registry

May 20, 2022

Completed
11 days until next milestone

Study Start

First participant enrolled

May 31, 2022

Completed
3.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 1, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

September 1, 2025

Completed
Last Updated

December 17, 2024

Status Verified

December 1, 2024

Enrollment Period

3.3 years

First QC Date

May 19, 2022

Last Update Submit

December 11, 2024

Conditions

Keywords

Olfactory trainingChemosensory impairmentsPersistent smell impairment

Outcome Measures

Primary Outcomes (5)

  • Changes from baseline in olfactory score on the University of Pennsylvania Identification Test (UPSIT) [ Time Frame: Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

    The UPSIT includes 4 odor-impregnated booklets that contain 10 forced-choice multiple choice questions each for participants to scratch-and-sniff to identify various odors and is a commercially available test. Normosmia is defined as ≥34 for males and ≥35 for females, and a change of 4 points or more from baseline indicates a clinically meaningful result.

    Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

  • Changes from baseline in olfactory score on the Sniffin's Sticks test

    Sniffin' Sticks test and Taste strips: Sniffin' Sticks test (Burghardt®, Wedel, Germany) is a psychophysical test. It allows semi-objective assessment of the patient's olfactory performance by means of 3 subtests: threshold test, identification test and discrimination test. The Sniffin' Sticks Olfactory Test Kits contain pen like bodies as, for example, in pens used to write on flipcharts or whiteboards.These pen-like bodies, however, contain a fibre stick which is filled with scents. For testing, the cap should be removed so the patient can smell on the tip of the pen.

    Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

  • n-house test for chemosensory dysfunction (TMSC)

    The TMSC is a 55-item questionnaire evaluating the three chemical senses: olfaction, taste and the trigeminal sense. First, questions with a 10-point visual analog scale make a subjective self-assessment of each of the three senses. Multiple-choice questions establish the precise characteristics of the dysfunctions of each of the senses if they are present. Secondly, a psychophysical test is administered remotely using substances typical of North American cuisines. Substances are first sniffed (peanut butter, jam, vinegar, coffee) then tasted (peanut butter, jam, salt water (1 tsp/250mL), sugar water (3 tsp/250mL)). The perceived intensity of each of the substances is reported each time on a visual analogue scale of 10 points.

    Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

  • Parosmia and phantosmia assessment test

    This test has a first part with four questions that aim to assess the presence of parosmia or phastosmia. Patients who have reported parosmia or phantosmia will be asked to complete a second part with six questions focusing on the quality of their olfactory distortion.

    Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

  • The abridged version of the Questionnaire of Olfactory Disorders - Negative Statements (sQOD-NS)

    The sQOD-NS is a validated questionnaire that measures the quality of life specific to olfactory functions. The questionnaire measures 7 items with a 4-point Likert scale.

    Measurement will be taken at time zero (pre-intervention) and 12 weeks (post-intervention)

Secondary Outcomes (1)

  • Nasal Obstruction Symptom Evaluation (NOSE)

    Measurement will be taken at time zero (pre-intervention)

Study Arms (2)

Chemosensory training group 1

EXPERIMENTAL

For 12 weeks, morning and evening, smell four odors namely eucalyptol, phenyl ethanol, Orange, and eugenol, for a total of five minutes per session.

Other: Smell training

Chemosensory training group 2

EXPERIMENTAL

For 12 weeks, morning and evening, smell four odors namely coffee aroma, cheese aroma, strawberries, and limon, for a total of five minutes per session.

Other: Smell training

Interventions

For 12 weeks, morning and evening, smell four different odors or four odorless substances for a total of five minutes per session.

Also known as: Chemosensory training group
Chemosensory training group 1Chemosensory training group 2

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Patient diagnosed positive for COVID-19 with persistent olfactory dysfunction
  • Willing and able to provide written informed consent
  • Understand and read the French language
  • Have an internet connection and a working email address

You may not qualify if:

  • Anosmia and hyposmia pre-covid-19
  • Be known chronic rhinosinusitis with or without nasal polyposis
  • Have received radiotherapy or chemotherapy for Head and Neck Tumors
  • Have a diagnosis of Alzheimer's, Parkinson's, multiple sclerosis or any other neurodegenerative disease 5. Have a brain tumor or ENT diagnosis 6. History of naso-sinus surgery; 7. History of traumatic brain injury

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Université du Québec à Trois-Rivières

Trois-Rivières, Quebec, G8Z 4M3, Canada

RECRUITING

MeSH Terms

Conditions

AnosmiaCOVID-19Olfaction Disorders

Interventions

Olfactory Training

Condition Hierarchy (Ancestors)

Sensation DisordersNeurologic ManifestationsNervous System DiseasesSigns and SymptomsPathological Conditions, Signs and SymptomsPneumonia, ViralPneumoniaRespiratory Tract InfectionsInfectionsVirus DiseasesCoronavirus InfectionsCoronaviridae InfectionsNidovirales InfectionsRNA Virus InfectionsLung DiseasesRespiratory Tract Diseases

Intervention Hierarchy (Ancestors)

Therapeutics

Study Officials

  • Johannes A Frasnelli, PhD

    Université du Québec à Trois-Rivières

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Johannes A Frasnelli, PhD

CONTACT

Frank Cloutier, PhD

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 19, 2022

First Posted

May 20, 2022

Study Start

May 31, 2022

Primary Completion

September 1, 2025

Study Completion

September 1, 2025

Last Updated

December 17, 2024

Record last verified: 2024-12

Locations