The relation between posttraumatic stress disorder and mild traumatic brain injury acquired during Operations Enduring Freedom and Iraqi Freedom

J Head Trauma Rehabil. Jan-Feb 2013;28(1):1-12. doi: 10.1097/HTR.0b013e318256d3d3.

Abstract

Objective: To understand the relations of mild traumatic brain injury (TBI), blast exposure, and brain white matter structure to severity of posttraumatic stress disorder (PTSD).

Design: Nested cohort study using multivariate analyses.

Participants: Fifty-two OEF/OIF veterans who served in combat areas between 2001 and 2008 were studied approximately 4 years after the last tour of duty.

Main measures: PTSD Checklist-Military; Combat Experiences Survey, interview questions concerning blast exposure and TBI symptoms; anatomical magnetic resonance imaging (MRI), and diffusion tensor imaging (DTI) scanning of the brain.

Results: PTSD severity was associated with higher 1st percentile values of mean diffusivity on DTI (regression coefficient [r] = 4.2, P = .039), abnormal MRI (r = 13.3, P = .046), and the severity of exposure to combat events (r = 5.4, P = .007). Mild TBI was not significantly associated with PTSD severity. Blast exposure was associated with lower 1st percentile values of fractional anisotropy on DTI (odds ratio [OR] = 0.38 per SD; 95% confidence interval [CI], 0.15-0.92), normal MRI (OR = 0.00, 95% likelihood ratio test CI, 0.00-0.09), and the severity of exposure to traumatic events (OR = 3.64 per SD; 95% CI, 1.40-9.43).

Conclusions: PTSD severity is related to both the severity of combat stress and underlying structural brain changes on MRI and DTI but not to a clinical diagnosis of mild TBI. The observed relation between blast exposure and abnormal DTI suggests that subclinical TBI may play a role in the genesis of PTSD in a combat environment.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Afghan Campaign 2001-
  • Anisotropy
  • Brain / pathology
  • Brain Injuries / diagnosis*
  • Brain Injuries / epidemiology
  • Cohort Studies
  • Diffusion Tensor Imaging
  • Explosions / statistics & numerical data
  • Female
  • Humans
  • Injury Severity Score
  • Iraq War, 2003-2011
  • Male
  • Military Personnel*
  • Multivariate Analysis
  • Occupational Exposure / adverse effects
  • Occupational Exposure / statistics & numerical data
  • Severity of Illness Index
  • Stress Disorders, Post-Traumatic / diagnosis*
  • Stress Disorders, Post-Traumatic / epidemiology
  • Surveys and Questionnaires