COVID-19
Conditions
Keywords
Olfactory training, Quality of life, Olfactory dysfunction, Covid-19, Parosmia
Brief summary
Aim: The aim is to investigate the effect of olfactory training with essential oils versus olfactory training with placebo-oils in patients with COVID-19 induced olfactory dysfunction Study design: The study is a placebo-controlled 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 (16.25-30.5) or anosmia (\<16) assessed by Sniffin' Sticks Olfactory Test for Threshold, Discrimination and Identification (TDI) performed in the Unit for Sense of Taste and Smell with or without parosmia based on medical history * \> 18 years of age Exclusion criteria: * Cause of hyposmia, anosmia or parosmia other than COVID-19 * 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. Questionnaires: \- 'Taste and Smell Tool for Evaluation' is used to investigate quality of life related to impaired sense of taste and smell.
Interventions
Olfactory training twice daily with essential oils from Urtegaarden Aps with scents of orange, lavender, clove and peppermint. The olfactory training is performed every morning and evening, by smelling each of the oils for 30 seconds.
OTHEROlfactory training with fragrance-free oils
Olfactory training twice daily with fragrance-free oils from Urtegaarden Aps in the same four containers as the intervention group. The olfactory training is performed every morning and evening, by smelling each of the oils for 30 seconds.
Sponsors
Ditte Gertz Mogensen
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Olfactory dysfunction caused by COVID-19 * Hyposmia (16.25-30.5) or anosmia (\<16) with or without parosmia assessed by TDI test with Sniffin Sticks performed in the Unit for Sense of Taste and Smell * \> 18 years of age
Exclusion criteria
* Cause of hyposmia, anosmia or parosmia other than COVID-19 * Does not read or speak Danish * Lack of compliance to perform daily olfactory training
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Extended Sniffin' Sticks Test score | 3 months follow-up | Change in TDI score measured by Burghart Extended Sniffin' Sticks Test (TDI test). The TDI test, consists of a threshold test, a discrimination test, and an identification test. The results of the three subtests makes a total TDI score, where the minimum score is 1 and the maximum score is 48. A score \>30 indicates normal olfactory function, a score between 15-30 indicates hyposmia and a score \<15 indicates anosmia in the form of severely impaired or complete loss of olfaction. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Quality of Life | 3 months follow-up | Change in Quality of Life measured by the questionnaire Taste and Smell Tool for Evaluation. The minimum score is 21 and the maximum score is 105. A higher score means worse outcome (quality of life). |
Countries
Denmark
Contacts
Primary ContactDitte G Gertz Mogensen, PhD-student
Backup ContactVibeke Backer, Professor
Outcome results
None listed