BreathinG-induced Myocardial and Cerebral Perfusion in Anxiety Disorders

Study Overview
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Brief Summary
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This study aims to view variations in MRI measurements of the heart and the brain in people with anxiety versus healthy volunteers. The MRI measurements used will be Oxygenation-Sensitive Cardiac MRI (OS-CMR), a recent type of MRI which is safe, fast, and non-invasive.

Detailed Description
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The investigators will prospectively analyze OS-CMR data from patients with a generalized anxiety disorder from one site. The investigators will observe how an anxiety disorder affects the OS-CMR data. In a follow-up MRI scan, the investigators will look at the OS-CMR of a subgroup who have anxiety disorder and are also undertaking cognitive behavioural therapy to asses how and if this therapy affects the OS-CMR data.

Official Title
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BreathinG-induced Myocardial and Cerebral Perfusion in Anxiety Disorders (B-GLAD)

Conditions
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Generalized Anxiety Disorder, Oxygenation Sensitive CMR

Intervention / Treatment
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* Diagnostic Test: Cardiac MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient population: Age 18-55, Confirmation of an anxiety disorder as identified by the PSWQ, No known, current or history, of significant medical conditions that may affect or directly involve the neurological, cardiovascular or respiratory system (except anxiety and depression) Non-smoker Healthy Volunteers: Age 18-55 No known, current or history, of significant medical conditions that may affect or directly involve the neurological, cardiovascular or respiratory system Non-smoker Exclusion Criteria: General MRI contraindications: pacemakers, defibrillating wires, implanted defibrillators, intracranial aneurysm clips, metallic foreign bodies in the eyes, pregnancy History of significant neurological disease or illness that is not anxiety (e.g. Dementia, stroke) Hemodynamically unstable conditions Significant or uncontrolled arrhythmias Severe pulmonary disease Recent (<90 days) myocardial infarction Recent (<90 days) surgery or coronary intervention Consumption of caffeine (caffeinated beverages, coffee, tea, cocoa, chocolate) within 12h of the exam Use of benzodiazepines or other short-acting anxiety medications (<1 day)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 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 |
| --- | --- |
| Patient Population<br>Participants diagnosed with Generalized Anxiety Disorder | Diagnostic Test: Cardiac MRI<br>* The 4-minute breathing maneuver comprised of 2 minutes of normal breathing and 1-min hyperventilation (rate of 30 breaths per minute) followed by a maximal breath-hold. This technique is used in Oxygenation Sensitive CMR, a type of MRI, and will induce a vasoactive response visible in cardiac and cerebral MRI images<br>* Other names: Breathing Maneuvers;|
| Healthy Volunteers<br>Participants with no pre-existing conditions and who are on no medications. | Diagnostic Test: Cardiac MRI<br>* The 4-minute breathing maneuver comprised of 2 minutes of normal breathing and 1-min hyperventilation (rate of 30 breaths per minute) followed by a maximal breath-hold. This technique is used in Oxygenation Sensitive CMR, a type of MRI, and will induce a vasoactive response visible in cardiac and cerebral MRI images<br>* Other names: Breathing Maneuvers;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Signal Intensity | Change in signal intensity between the baseline signal intensity and the signal intensity at 30 seconds of breath hold | Baseline |