Summary

Background: Whereas procoagulation abnormalities in acute stress are well established, little is known about the mechanism of hypercoagulation in chronic stress, such as post-traumatic stress disorder (PTSD). This is crucial, given the fact that chronic coagulation disturbances have been associated with increased morbidity and premature mortality due to thromboembolism and cardiovascular disorders, complications recently described in PTSD patients.

Objectives: To explore the mechanisms of hypercoagulation in chronic PTSD.

Methods: Thirty patients diagnosed with chronic PTSD were enrolled and compared with a control group matched for age, gender and ethnicity. Hypercoagulation state was evaluated by levels of fibrinogen, D-dimer, prothrombin fragment F 1+2, von Willebrand factor (vWF) antigen, factor VIII activity, activated protein C resistance, ProC Global assay, and tissue factor antigen. Psychiatric evaluation was performed using the Mini-International Neuropsychiatric Interview and Clinician Administered PTSD Scale (CAPS).

Results: vWF antigen levels were significantly higher in patients with chronic PTSD compared with the controls (121.3 ± 42 vs. 99.7 ± 23, respectively, P = 0.034). Higher levels of vWF antigen and factor VIII activity were found in patients with severe chronic PTSD (CAPS > 80), compared to controls and patients with chronic PTSD and less severe symptoms (CAPS ≤ 80). However, no differences were observed in any other studied coagulation parameters between patients and controls.

Conclusions: Increased levels of vWF antigen and factor VIII activity were documented in severe chronic PTSD. These findings suggest that the higher risk of arterial and venous thromboembolic events in PTSD patients could be related to endothelial damage or endothelial activation.