Reactivity of the Vestibular System to Caloric Vestibular Stimulation in Schizophrenia

Healthy Clinical Trial

Official title:

Reactivity of the Vestibular System to Caloric Vestibular Stimulation in Schizophrenia

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03048370
• Other study ID #: 042-2016
• Status: Completed
• Phase: N/A
• Start date: January 1, 2019
• Est. completion date: December 31, 2023

Study information

• Verified date: February 2024
• Source: Centre for Addiction and Mental Health
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study aims to determine if individuals with schizophrenia have greater reactivity to vestibular stimulation than healthy controls. The physiological response of vestibular stimulation will be assessed with electronystagmography, which provides a measure of the intensity of the nystagmus via PSPV. Positive results would suggest greater vestibular system reactivity to vestibular stimulation may be a biomarker of schizophrenia. Pathophysiologically, increased vestibular reactivity to vestibular stimulation may reflect abnormal vestibular function or impaired central suppression of the vestibular ocular reflex.

Description:

In schizophrenia, there is no conclusive link between psychopathology and vestibular dysfunction and we are not aware of any data that exists on the range of responses to caloric vestibular stimulation (CVS) in persons with schizophrenia. Initial data from another CVS study from our group suggests individuals with schizophrenia have greater reactivity to body temperature (37°C) CVS, as measured by the peak slow phase velocity of the resulting nystagmus (PSPV), than would be expected from individuals without schizophrenia versus healthy participants. Intriguingly, CVS at 37°C should not theoretically produce a significant vestibulocular reflex response due to the stimulus' approximation to body temperature. Hence, the primary aim of this study is to determine if individuals with schizophrenia will have greater vestibular reactivity, as measured by nystagmus PSPV, to CVS in comparison with healthy participants. The secondary aim is to assess illness awareness pre and post CVS administration in attempts to replicate our previous observation. A total of 20 patients with schizophrenia and 20 healthy control participants will be recruited. All participants will receive three conditions bilaterally: (1) body temperature (37°C) vestibular stimulation; (2) warm CVS (44°C), and (3) cold CVS (30°C).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: December 31, 2023
• Est. primary completion date: December 31, 2023
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria for Schizophrenia group:

1. Male or female inpatients or outpatients age =18

2. Having a DSM-5 diagnosis of schizophrenia or schizoaffective disorder

3. Voluntary and capable of consenting to participation in the research study

4. Fluent in English

Inclusion Criteria for Healthy Controls group:

1. Male or female and age =18

2. Voluntary and capable of consenting to participation in the research study

3. Fluent in English

4. Absence of history of psychiatric illness using the Mini-International Neuropsychiatric Interview (MINI)

Exclusion Criteria for all participants:

1. Serious unstable medical illness or any concomitant major medical or neurological illness

2. Acute suicidal and/or homicidal ideation

3. Formal thought disorder rating of over 2 on the Scale for Assessment of Positive Symptoms (SAPS) [patients only]

4. DSM-IV substance dependence (except caffeine and nicotine) within one month prior to entering the study

5. Pregnant women

6. Positive urine drug screen

7. History of external or middle ear pathology

8. History or signs of middle ear surgery (e.g. Tympanoplasty, mastoidectomy)

9. Signs of active ear disease

Related Conditions & MeSH terms

• Healthy
• Schizophrenia

Intervention

Procedure:
• Left body temperature VS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
• Right body temperature VS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
• Left warm CVS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
• Right warm CVS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
• Left cold CVS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
• Right cold CVS
Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function

Locations

Country	Name	City	State
Canada	Centre for Addiction and Mental Health	Toronto	Ontario

Sponsors (1)

Lead Sponsor	Collaborator
Centre for Addiction and Mental Health

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Nystagmus response (peak slow phase velocity)	Nystagmus response will be measured at between thirty and 60 seconds post irrigations, looking for the highest velocities.	Between 30 and 60 sec after each CVS condition
Secondary	Illness awareness	Changes in illness awareness will be assessed using a questionnaire.	Before CVS session and10 min after CVS session

External Links

•   Information about research at the Centre for Addiction and Mental Health, Canada's largest mental health and addiction teaching hospital, fully affiliated with the University of Toronto, and a PAHO/WHO Collaborating Centre