Characteristics of the Anosmic Olfactory Mucosa

Active, not recruiting

• Conditions: Anosmia; Head Injury; COVID-19

• Registration Number: NCT05562050
• Lead Sponsor: Nicolai Nielsen

Brief Summary

The present study aims to describe the structural tissue and cell characteristics of the olfactory mucosa in patients with persistent anosmia (≥2 years) due to COVID-19 or head-trauma, in comparison to healthy individuals with intact olfactory function. In order to avoid possible age-related degenerative changes in the neuro-epithelium, both patients and controls are between 25 and 35 years of age.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-09-28
• Study First Submitted QC: 2022-09-28
• Study First Posted: 2022-09-30
• Study Start: 2023-11-01
• Status Verified: 2024-08
• Last Update Submitted: 2024-08-13
• Last Update Posted: 2024-08-14
• Primary Completion: 2024-10-01
• Study Completion: 2024-10-30

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 18

Inclusion Criteria

• Legally competent to vouch for their own study participation.

• Informed and written consent for participation in this study.

• Study group 1 (Post-COVID anosmia)

  1. Diagnosed with persistent anosmia for approximately two years concurring with positive SARS-CoV-2 PCR-test between 2019 and 2020.
  2. Sniffin'sticks test with a threshold-discrimination-identification-score(TDI)≤16
  3. Between 25 and 35 years of age.

Study group 2 (Post-trauma anosmia)

1. Diagnosed with persistent anosmia for approximately two years concurring with head trauma.
2. Sniffin'sticks test with a threshold-discrimination-identification-score(TDI)≤16
3. Between 25 and 35 years of age.

Study group 3 (Controls):

1. Between 25 and 35 years of age.
2. Undergoing reposition of a nasal fracture in general anaesthesia

Exclusion Criteria

• <25 years of age.

• >35 years of age.

• Chronic rhinosinusitis with/without polyps.

• Nasal cancer.

• Presence of viral or bacterial rhinosinusitis.

• Uncontrolled allergic rhinosinusitis.

• Coagulation deficiencies, e.g. haemophilia.

• Use of anticoagulants.

• Not able to undergo general anaesthesia.

• Pregnancy.

• Any use of nasal detumescence drugs ≤2 weeks before biopsy.

• Any use of nasal steroids ≤3 months before biopsy.

• Use of nasal inhaled recreational drugs ≤3 month before biopsy.

• Participants not able to communicate in Danish or English.

• Major Depression Inventory (MDI) score ≥27 [49, 50]

• Mini Mental State Examination (MMSE) score ≤ 26 [51]

• Study group 1 (Post-COVID anosmia)

  1. Anosmia for less than two years or more than two and a half years.
  2. No positive SARS-CoV-2 PCR-test concurring with olfactory dysfunction.
  3. History of olfactory dysfunction before COVID-19 infection.

• Study group 2 (Post-trauma anosmia)

  1. Anosmia for less than two years or more than approximately two-three years.
  2. Anosmia without concurring with head trauma
  3. History of prior olfactory dysfunction before head trauma.

• Study group 3 (Controls) 1. Known olfactory dysfunction.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Histological evaluation	2023-2024	density
Immunohistochemical evaluation	2023-2024	density

Trial Locations

Locations (1)

ENT department; 🇩🇰 Herning, Denmark