Association Between Smell Training and Quality of Life in Patients With Impaired Sense of Smell Following COVID-19 — SMELLT2022  

COVID-19 Clinical Trial

Official title: Association Between Olfactory Training and Quality of Life in Patients With Impaired Sense of Taste and Smell Following COVID-19

Status Recruiting

Clinical Trial Summary

Aim: The aim is to investigate whether guided systematic olfactory training with essential oils to improve impaired sense of smell following COVID-19, can improve patients' quality of life.

Hypothesis: The impaired quality of life in patients with impaired sense of smell following COVID-19, can be significantly improved in patients performing olfactory training with essential oils, compared to patients performing olfactory training with placebo oils.

Study design: The study is a randomized clinical trial with an intervention group and a control group. The intervention group receive four essential oils with scents of orange, lavender, clove, and peppermint. Patients in the control group receive a fragrance kit, consisting of the same containers, but with fragrance-free oils added. Both groups are instructed to smell each of the four oils for 30 seconds in the morning and evening, over a three-month intervention period. Patients are given a diary in which to record their olfactory training. The nurse or medical student instructing the patients in the training and performing the smell and taste tests is blinded.

Study population: Patients referred to the Unit for Sense of Taste and Smell in the Department of Otorhinolaryngology Head & Neck and Audiology at Rigshospitalet.

Inclusion criteria:

• Impaired sense of taste and smell following COVID-19 > 3 months

• Hyposmia (15-30) or anosmia (<15) assessed by Sniffin' Sticks Olfactory Test for Threshold, Discrimination and Identification (TDI) performed in the Unit for Sense of Taste and Smell or medical assessment of parosmia based on medical history

• > 18 years of age

Exclusion criteria:

• Cause of hyposmia, anosmia or parosmia other than COVID-19

• Impaired sense of taste and smell >24 months

• Does not read or speak Danish

• Lack of compliance to perform daily olfactory training

Procedures:

• TDI-test: To assess patients' sense of smell, the TDI-test with Sniffin' Sticks is used, which is a validated tool with normative data.

• Taste test: To assess patients' sense of taste, taste sprays with the basic tastes are used.

Questionnaires:

• 'Taste and Smell Tool for Evaluation' is used to investigate quality of life related to impaired sense of taste and smell.

• 'Major Depression Inventory' (MDI) is used in the project to assess whether the patient is depressed and to make a possible assessment of the severity of depression.

Clinical Trial Description

n/a

Related Conditions & MeSH terms

• COVID-19

• NCT number: NCT05539560
• Study type: Interventional
• Source: Rigshospitalet, Denmark
• Contact: Ditte G Gertz Mogensen, PhD-student
• Phone: +45 35457508
• Email: ditte.gertz.mogensen@regionh.dk
• Status: Recruiting
• Phase: N/A
• Start date: June 29, 2022
• Completion date: September 30, 2025