Hearing Loss, Vestibular Loss and Cognitive Performance

Study Overview
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Brief Summary
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Hearing loss is an established independent risk factor for dementia. Likewise, recent research demonstrated cognitive deficits in subjects with vestibular loss. However, in these studies data have not been adjusted for the hearing status of the enrolled study subjects. As hearing loss prevalence is high in patients with vestibular loss, this could be a major confounder. Therefore, in this study the investigators investigate cognition in patients with bilateral vestibulopathy with and without hearing loss. The investigators adjust data for the hearing status of the patients to explore the link between hearing loss, vestibular loss and cognition.

Official Title
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The Link Between Hearing Loss, Vestibular Loss and Cognitive Performance: Cross-sectional Data in Patients With Bilateral Vestibulopathy

Conditions
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Vestibular Disorder

Intervention / Treatment
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* Behavioral: RBANS-H, virtual Morris Water Maze


Participation Criteria
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Eligibility Criteria
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Inclusion criteria for BVP patients were: Bilaterally reduced vestibular function, as defined by the Bárány Criteria for BVP (Michael Strupp 2017): horizontal angular VOR gain < 0.6 measured by the vHIT, and/or reduced caloric response (sum of bithermal, 30° and 44°, max. peak slow phase velocity (SPV) on each side < 6°/sec), and/or reduced horizontal angular VOR gain < 0.1 upon sinusoidal stimulation on a rotatory chair. At our clinic rotatory chair tests are performed using sinusoidal rotation (0.05 Hertz) with a peak velocity of 60°/sec (Van der Stappen A 2000). Disease duration of BVP > 6 months. Healthy controls (HC). Only subjects with no history of vertigo, scores <5 on the Dizziness Handicap Inventory (DHI) and normal hearing thresholds at 0.25 - 8 kHz, based on age and sex (defined by the BS 6951:1988, EN 27029:1991 and ISO 7029-1984 standards), were enrolled in the study. For both BVP patients and HC the following additional inclusion criteria were applied: 1) Age ≥ 18 years; 2) Fluency in Dutch; 3) No history of neurological diseases (e.g. dementia, Parkinson's disease, cerebrovascular accident, etc.); 4) Absence of clinical signs indicating dementia or mild cognitive impairment.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Bilateral vestibulopathy<br>Patients with bilateral vestibulopathy, according to the Barany Criteria (2017, Strupp). | Behavioral: RBANS-H, virtual Morris Water Maze<br>* Cognitive tasks for respectively: general cognition and spatial cognition<br>|
| Healthy controls<br>Subjects without vestibular or neurological diseases (DHI<5), and with normal hearing thresholds according to their age. | Behavioral: RBANS-H, virtual Morris Water Maze<br>* Cognitive tasks for respectively: general cognition and spatial cognition<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Repeatable Battery for the Assessment of Neuropsychological Status for Hearing Impaired Individuals (RBANS-H): total score | General cognitive assessment, cfr. Claes et al 2016. The total-score is standardized with a mean of 100 and a standard deviation of 15. The higher the total score, the better the cognition of the participant. | 2 years | 
| Virtual Morris Water Maze performance | Spatial cognition assessment, cfr. Hamilton. Path length and latency are recorded, the higher the worse the spatial cognition of the participant. | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Repeatable Battery for the Assessment of Neuropsychological Status for Hearing Impaired Individuals (RBANS-H): index scores | Cfr. Claes et al 2016. The subscale are standardized with a mean of 100 and standard deviation of 15. The higher the score, the better the performance on a specific subdomain of cognition (attention, immediate memory, delayed memory, visuospatial and language) | 2 years |