Post-traumatic stress disorder (PTSD) accounts for a substantial portion of the total mental health burden in Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) warfighters and veterans. The underlying biological pathology of PTSD is not yet known, and diagnosis is exclusively based on clinical behavioral features, which are often under- or over-reported. PTSD is associated with increased risk for serious medical illnesses and premature death, but the mechanisms underlying this risk are not known. Discovering biomarkers of PTSD would aid: in diagnosis; in redefining the illness along biologically homogeneous dimensions; in staging the course of the illness; and in highlighting potential targets for treatment. Research to date has highlighted several candidate biomarkers of PTSD, but none has sufficient sensitivity, specificity or prognostic significance for clinical practice. Evaluating promising biomarkers in tandem in the same subjects holds greater hope for identifying interactions among biomarkers that may be more helpful in diagnosing this condition. For example, uncovering the degree of dysregulation across multiple biological systems (e.g., allostatic load) in PTSD should help in furthering our understanding of the biological mechanisms underlying disease risk in PTSD.

The overall objective of the proposed research is to identify potential biomarkers of PTSD using an extensive biological protocol, including several novel biomarkers of great potential significance that have not been adequately studied in this disorder.