Brain-derived neurotropic factor polymorphisms, traumatic stress, mild traumatic brain injury, and combat exposure contribute to postdeployment traumatic stress.
In addition to experiencing traumatic events while deployed in a combat environment, there are other factors that contribute to the development of posttraumatic stress disorder (PTSD) in military service members. This study explored the contribution of genetics, childhood environment, prior trauma, psychological, cognitive, and deployment factors to the development of traumatic stress following deployment.



Both pre- and postdeployment data on 231 of 458 soldiers were analyzed. Postdeployment assessments occurred within 30 days from returning stateside and included a battery of psychological health, medical history, and demographic questionnaires; neurocognitive tests; and blood serum for the D2 dopamine receptor (DRD2), apolipoprotein E (APOE), and brain-derived neurotropic factor (BDNF) genes.



Soldiers who screened positive for traumatic stress at postdeployment had significantly higher scores in depression (d = 1.91), anxiety (d = 1.61), poor sleep quality (d = 0.92), postconcussion symptoms (d = 2.21), alcohol use (d = 0.63), traumatic life events (d = 0.42), and combat exposure (d = 0.91). BDNF Val66 Met genotype was significantly associated with risk for sustaining a mild traumatic brain injury (mTBI) and screening positive for traumatic stress. Predeployment traumatic stress, greater combat exposure and sustaining an mTBI while deployed, and the BDNF Met/Met genotype accounted for 22% of the variance of postdeployment PTSD scores (R (2)  = 0.22, P < 0.001). However, predeployment traumatic stress, alone, accounted for 17% of the postdeployment PTSD scores.



These findings suggest predeployment traumatic stress, genetic, and environmental factors have unique contributions to the development of combat-related traumatic stress in military service members.
U.S. Army Aeromedical Research Laboratory 6901 Farrel Road Fort Rucker Alabama 22206; National Intrepid Center of Excellence Walter Reed National Military Medical Center 4860 South Palmer Road Bethesda Maryland 20889; Human Dimension Division (HDD) Headquarters Army Training and Doctrine Command (HQ TRADOC) 950 Jefferson Ave Fort Eustis Virginia 23604.
Michael N
MN
Dretsch
National Intrepid Center of Excellence Walter Reed National Military Medical Center 4860 South Palmer Road Bethesda Maryland 20889.
Kathy
K
Williams
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Tanja
T
Emmerich
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Gogce
G
Crynen
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Ghania
G
Ait-Ghezala
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Helena
H
Chaytow
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Venkat
V
Mathura
Roskamp Institute 2040 Whitfield Ave Sarasota Florida 34243.
Fiona C
FC
Crawford
Department of Physical Medicine and Rehabilitation Harvard Medical School Boston Massachusetts; Spaulding Rehabilitation Hospital Boston Massachusetts; Red Sox Foundation and Massachusetts General Hospital Home Base Program Boston Massachusetts; Defense and Veterans Brain Injury Center Bethesda Maryland; Center for Health and Rehabilitation Department of Physical Medicine & Rehabilitation Harvard Medical School 79/96 Thirteenth Street Charlestown Navy Yard Charlestown Massachusetts 02129.
Grant L
GL
Iverson
D000328:Adult; D001924:Brain Concussion / Q000150:complications* / Q000523:psychology; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood / Q000235:genetics*; D005260:Female; D006801:Humans; D054542:Iraq War, 2003-2011; D008297:Male; D008889:Military Personnel / Q000523:psychology / Q000706:statistics & numerical data; D011110:Polymorphism, Genetic / Q000235:genetics*; D011446:Prospective Studies; D013313:Stress Disorders, Post-Traumatic / Q000097:blood / Q000150:complications* / Q000235:genetics; D013315:Stress, Psychological / Q000150:complications* / Q000523:psychology
D019208:Brain-Derived Neurotrophic Factor
BDNF; deployment; genetics; military; posttraumatic stress disorder; psychological health; traumatic brain injury