Cardiovascular and Neurovascular Regulation in GWI

Study Overview
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Brief Summary
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Brain blood flow regulation and autonomic dysfunction will be measured in Veterans with and without Gulf War Illness who served in the Gulf War between 1990 and 1992.

Detailed Description
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Gulf War Illness (GWI) is a multi-symptom illness with unknown etiology. GWI is a leading cause of disability in Gulf War Veterans. Cognitive complaints are a common symptom of GWI, which suggests the brain is involved in the development of this condition. As Veterans age, these cognitive complaints may worsen and be compounded by the aging process. GWI may be a condition of accelerated brain aging. Therefore, there may be long-term consequences of GWI, and the presence of GWI may increase a person's risk for developing Alzheimer's Disease (AD) or other dementias. In comparison to other brain-related diseases such as stroke, relatively little is known about GWI and how this condition impacts the normal age-related changes in the brain. The research aims are: To determine if Veterans with Gulf War Illness demonstrate abnormal brain blood flow regulation and autonomic dysfunction when compared with Veterans without Gulf War Illness. To determine if brain blood flow and autonomic nervous system variables in Veterans are associated with other markers of brain aging that are relevant to cognitive decline.

Official Title
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Autonomic Dysfunction, Brain Blood Flow and Cognitive Decline in Veterans With Gulf War Illness

Conditions
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Brain Blood Flow, Neurovascular Control

Intervention / Treatment
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* Device: MRI
* Device: Transcranial Doppler Ultrasound
* Other: Sympathetic Nerve Activity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Deployed to the Persian Gulf between 1990-1992 Body mass <300 lbs Diagnosis of Gulf War Illness based on CMI/CDC and Kansas definitions or No diagnosis of Gulf War Illness Exclusion Criteria: Current or lifetime evidence of: Type II diabetes, neurological disease, cancer treatment, rheumatoid arthritis, lupus, bipolar disorder, psychotic disorders, or mood disorders with psychotic features Current illicit substance use or partial remission for less than 1 year Taking multiple sedatives or anticonvulsant medications Currently pregnant Absolute contraindications to exercise testing Contraindications to MRI Other significant medical conditions at investigator's discretion

Ages Eligible for Study
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Minimum Age: 45 Years
Maximum Age: 68 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 |
| --- | --- |
| Veterans with GWI<br>Veterans with GWI who served in the Gulf War between 1990 and 1992 | Device: MRI<br>* Participants will undergo an MRI scan while participating in a breathing test to measure brain blood flow.<br>Device: Transcranial Doppler Ultrasound<br>* Participants will undergo a TCD scan while participating in a breathing test to measure brain blood flow.<br>Other: Sympathetic Nerve Activity<br>* Participants will undergo sympathetic nerve activity testing while participating in a breathing test.<br>|
| Veterans without GWI (Controls)<br>Veterans without GWI who served in the Gulf War between 1990 and 1992 | Device: MRI<br>* Participants will undergo an MRI scan while participating in a breathing test to measure brain blood flow.<br>Device: Transcranial Doppler Ultrasound<br>* Participants will undergo a TCD scan while participating in a breathing test to measure brain blood flow.<br>Other: Sympathetic Nerve Activity<br>* Participants will undergo sympathetic nerve activity testing while participating in a breathing test.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brain blood flow measured using Transcranial Doppler ultrasound | Neurovascular control will be investigated by measuring the change in brain blood flow using a transcranial Doppler ultrasound in response to a breathing test. | Baseline | 
| Brain blood flow measured using MRI | Neurovascular control will be investigated by measuring the change in brain blood flow using an MRI in response to a breathing test. | Baseline | 
| Sympathetic nerve activity | Neurovascular control will be investigated by measuring the change in sympathetic nerve activity will be measured using microneurography in response to a breathing test. | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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MRI, Brain Blood Flow, Sympathetic Nerve Activity, Cardiorespiratory Fitness