Key Dimensions of PTSD and ED

Study Overview
=================
Brief Summary
-----------------
This study will test whether endothelial dysfunction could be the early subclinical mechanism by which posttraumatic stress disorder (PTSD) increases cardiovascular disease (CVD) risk, and whether posttraumatic fear-a key component of PTSD-or another PTSD dimension could be the target to offset that risk. The results of this study may help trauma-exposed individuals who are at risk of having CVD events.

Detailed Description
-----------------
Posttraumatic stress disorder (PTSD) increases risk of incident cardiovascular disease (CVD) by 25-50%. Most individuals (50-90%) experience a traumatic event in their lifetime, and PTSD is the fifth most common psychiatric disorder. Experts have now called for increased CVD surveillance after trauma and for PTSD treatment trials powered to reduce CVD risk. However, both CVD risk and PTSD are complex phenomena that likely interact in nuanced ways. This study will determine which PTSD dimension(s) contribute to endothelial dysfunction, one of the earliest modifiable precursors to CVD. The investigators will examine cross-sectional and longitudinal associations of PTSD and its underlying dimensions with functional and, secondarily, cellular measures of endothelial dysfunction (FMD and circulating endothelial cell-derived microparticles, respectively) in a community-dwelling sample of CVD-free adult men and women with a history of trauma (50% with current PTSD).

Official Title
-----------------
Key Dimensions of Post-traumatic Stress Disorder (PTSD) and Endothelial Dysfunction (ED)

Conditions
-----------------
Trauma, PTSD, Endothelial Dysfunction

Intervention / Treatment
-----------------
* Behavioral: Psychophysiological fear conditioning and extinction task
* Behavioral: Eyetracking task


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Aged 18+ years History of exposure to a psychological trauma (e.g., natural disaster, physical assault) Fluent in English Willing to and capable of providing informed consent Additional Inclusion Criteria for the PTSD Group Diagnosed with current PTSD (duration of at least 1 month) using the Clinician-Administered PTSD Scale for Diagnostic and Statistical Manual 5th Edition (DSM-5) (CAPS-5) at the diagnostic interview assessment Exclusion Criteria: History of CVD (i.e., diagnosis of myocardial infarction, unstable angina, heart failure, peripheral artery disease, or stroke) Deemed unable to comply with the protocol (either self-selected or by indicating during screening that could not complete all requested tasks) Current bipolar disorder or psychotic disorder Mild or more severe cognitive impairment [Mini-Mental State Exam (MMSE)3 score ≤18] Current moderate or severe substance use disorder Acute, unstable, or severe medical disorder or pregnancy Deemed to need immediate psychiatric intervention (e.g., active suicidality) Use of antipsychotic, mood stabilizer, antidepressant, or stimulant medication in the past 4 weeks Daily benzodiazepine use in the past 2 weeks Additional Exclusion Criteria for the Trauma-Exposed Matched Control Group Current or past diagnosis of any DSM-5 psychiatric disorder CAPS-5 total score ≥25

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Trauma exposed without PTSD<br>Individuals with a history of trauma exposure who do not have current PTSD | Behavioral: Psychophysiological fear conditioning and extinction task<br>* Behavioral task to assess psychophysiological measures of fear<br>Behavioral: Eyetracking task<br>* Behavioral task to assess dysphoria-relevant attention allocation<br>|
| Trauma exposed with PTSD<br>Individuals with a history of trauma exposure and a current diagnosis of PTSD | Behavioral: Psychophysiological fear conditioning and extinction task<br>* Behavioral task to assess psychophysiological measures of fear<br>Behavioral: Eyetracking task<br>* Behavioral task to assess dysphoria-relevant attention allocation<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Flow-mediated dilation of the brachial artery (FMD) % | FMD is the percent difference in diameter of the brachial artery, before and after occlusion. Impaired endothelial function occurs when blood vessels are unable to dilate fully in response to nitric oxide synthesis and release, which is manifested as impaired endothelium-dependent vasodilation (i.e., lower FMD). Lower FMD has been associated with the degree of coronary atherosclerosis and predicts CVD events. | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Circulating EMPs expressing CD62E | EMPs expressing CD62E (i.e., endothelial cell activation) and CD31 (i.e., endothelial cell apoptosis) will be measured. Assessments of circulating EMPs will be measured using flow cytometry, and total flow cytometry counts will be converted to the number of EMPs per uL of blood. Higher concentrations of EMPs expressing CD62E and CD31 indicate greater endothelial dysfunction. | Baseline | 
| Circulating EMPs expressing CD31 | EMPs expressing CD62E (i.e., endothelial cell activation) and CD31 (i.e., endothelial cell apoptosis) will be measured. Assessments of circulating EMPs will be measured using flow cytometry, and total flow cytometry counts will be converted to the number of EMPs per uL of blood. Higher concentrations of EMPs expressing CD62E and CD31 indicate greater endothelial dysfunction. | Baseline | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Trauma, PTSD, Endothelial Dysfunction