REEDUCATION OF OLFACTORY DISORDERS AFTER A CEREBRAL VASCULAR ACCIDENT IN ADULTS

NCT04703218 | Terminated

• 1 other identifier: 20-055
• Study Type: interventional
• Target: 3
• Locations: 1 country
• Sites: 1

Brief Summary

Study context: The literature identifies more and more research revealing olfactory disorders, with a high frequency after an acquired brain injury. So far, studies have mainly focused on post-traumatic and post-infectious olfactory disorders of the upper airways. There is scarcer data available on the olfactory disorders occurring after stroke. A recent study found 43.6% of patients with a loss of olfactory function after a stroke (2). This type of disorder can have repercussions in everyday life and endanger people, not being able to smell a burning odor or gas fumes. In addition, patients frequently describe loss of pleasure associated with these olfactory disorders (3). Tests allowing the evaluation of these difficulties exist but remain little used in clinical routine (4). These psychophysical tests allow a quantitative analysis of the olfactory capacities of subjects through various measures such as the detection threshold (T SST sub-score), discrimination (D SST sub-score) or the identification of an odor. (SST sub-score I). Some studies have shown a reduction in olfactory disturbances following specific training. Thus, Hummel et al. proposed a self-stimulation protocol to patients whose olfactory dysfunction was due to various aetiologies (post-infectious, post-traumatic or idiopathic) (5). People were to smell 4 scents twice a day for 12 weeks. The results show an improvement in the olfaction of the patients, while no change was noted in the subjects who did not perform the training. Lehrer et al. obtained similar results in patients with head trauma (CT) after 3 months of training (6). However, no study has looked at the effect of specific olfaction training in post-stroke patients. The few data available in the literature suggest that these disorders are common after stroke. Objectives : We propose an open, randomized controlled study, comparing the SST score between the group of patients who received olfactory training and the group who received standard rehabilitation. Material and methods : In the treatment of post-stroke olfactory disorders, we will suggest to patients hospitalized in SSR or followed in consultation to participate in a controlled, randomized open study. All included patients will be assessed using the SST and the modified ASOF quality of life questionnaire (7). After randomization, patients in the treatment group will benefit from a presentation of specific olfaction training. This training consists of smelling 4 scents twice a day using scent sticks, for 12 weeks. At the end of these 12 weeks, a post-protocol evaluation including the SST, the modified ASOF quality of life questionnaire and a measurement of any side effects related to training will be offered. Hypothesis tested: The aim of this work is to evaluate the effectiveness of a specific olfaction training protocol in patients with olfaction disorders following stroke.

Conditions

Adult With Stroke and Olfaction's Complaint

Outcome Measures

Primary Outcomes (1)

• TDI score obtained in SST after the training period (12 weeks)

  3 months

Secondary Outcomes (7)

• Score obtained on the ASOF quality of life questionnaire modified after training (12 weeks)

  3 months

• T, D and I sub-scores obtained in SST after training (12 weeks)

  3 months

• Number of complaints about side effects and possible discomfort related to training

  3 months and 6 months

• Number of training stops (training < 12 weeks)

  3 months

• score obtained in the SST after training (12 weeks)

  3 months

Study Arms (2)

Patients with stroke and olfaction disorder benefiting from specific olfaction training.

EXPERIMENTAL

Other: olfactory rehabilitation

Patients with stroke and olfactory disorder benefiting from standard post-stroke rehabilitation

NO INTERVENTION

Interventions

olfactory rehabilitation OTHER

Olfactory rehabilitation consists of smelling 4 scents twice a day using scent sticks, for 12 weeks

Patients with stroke and olfaction disorder benefiting from specific olfaction training.

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult patient under 65 in order to avoid presbyosmia bias,
• Patient suffering from an ischemic and / or hemorrhagic stroke dating at least 3 months,
• Patient followed in the SRH department and / or in post-stroke consultation,
• French-speaking patient,
• Patient affiliated to the social security scheme,
• Patient having signed the informed consent.

You may not qualify if:

• Patient with a TDI score greater than 30.5 on the SST,
• Patient with global aphasia: score \<25 on the oral comprehension subtest of MT86 sentences (1),
• Person under legal protection (guardianship, curatorship, safeguard of justice),
• Patient treated with corticosteroids, corticosteroids, steroids, antihistamines and antibiotics which may have repercussions on olfaction,
• History of trauma to the face,
• History of ENT surgery,
• Chronic rhinitis,
• Neurodegenerative pathology,
• Parosmia, phantosmia or cacosmia,
• History of systemic chemotherapy or radiotherapy to the head.

Sponsors & Collaborators

• University Hospital, Caen: lead

Study Sites (1)

Caen University Hospital

Caen, France

Location

MeSH Terms

Interventions

Olfactory Training

Intervention Hierarchy (Ancestors)

Therapeutics

Study Design

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

Study Record Dates

• First Submitted: January 7, 2021
• First Posted: January 11, 2021
• Study Start: January 11, 2022
• Primary Completion: November 16, 2022
• Study Completion: November 16, 2022
• Last Updated: July 25, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)