Olfactory and Trigeminal Functions in Patients With Multiple Sclerosis: Case-control Study

Summary

The sensation of smell is influenced by the somatosensory and chemesthetic sensati¬ons of the nose: for example, the cooling sensation of menthol or the prickle of carbon dioxide from carbonated drinks. These sensations are mediated in the nose by the trigeminal nerve and there is increasing evidence that trigeminal and olfactory functions are closely linked and potentially interdependent. In addition, trigeminal activation is crucial to the perception of nasal airflow. Some researchers speculate about the impact of trigeminal nerve on the entire olfactory sensation and about the presence of some specific "trigeminal cells" into the nose.Patients with Multiple sclerosis (MS) can suffer from quantitative olfactory disorders that generally are of light entity and do not interfere with daily life activities but it is important to underline that olfactory loss can be an onset sign of the MS. Considering the "trigeminal component" in the olfaction, because trigeminal nerve inflammation is quite common in MS patients due to central and peripheral inflammation, it could be possible that these patients suffer from changes in the quantitative, but more in the qualitative smell functions that are generally not identified because poorly investigated.

Conditions

• Multiple Sclerosis

Interventions

DIAGNOSTIC_TEST

TDI

Sniffin' Sticks Threshold and Identification Test

DIAGNOSTIC_TEST

Trigeminal Test

Test the trigeminal smell answer by a device that releases air and a substance that stimulates the trigeminal response

DIAGNOSTIC_TEST

Cognitive Evaluation by Montreal Cognitive Assessment

Montreal Cognitive assessment

DIAGNOSTIC_TEST

Anxiety and Depression questionnaire

Specific test to evaluate patient's mood

DIAGNOSTIC_TEST

Visual Analogue Scale Ratings

* Smell ability (How is your sense of smell right now? 0 cannot smell, 1-3 severe impairment, 4-6 moderate impairment, 7-9 mild impairment, 10 normal) * Nasal breathing (How well can you breathe through your nose right now? 0 complete nasal obstruction, 1-3 severe impairment, 4-6 moderate impairment, 7-9 mild impairment, 10 normal)

DIAGNOSTIC_TEST

Quality of smell Questionnaire

Patients will answer to a validated questionnaire

Sponsors & Collaborators

• University of Roma La Sapienza

  collaborator OTHER

• Hospital General Universitario Santa Lucia

  collaborator OTHER

• Klinik und Poliklinik fur Kinderheilkunde

  collaborator OTHER

• University of Catania

  lead OTHER

Eligibility

Min Age

18 Years

Max Age

55 Years

Sex

FEMALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-05-30

Primary Completion

2026-12-30

Completion

2028-12-30

Countries

• Italy

Study Locations