Childhood trauma, combat trauma, and substance use in National Guard and reserve soldiers

Background: The goal of this work was to examine associations among childhood trauma, combat trauma, and substance use (alcohol problems, frequent heavy drinking [FHD], current cigarette smoking, and current/lifetime drug use) and the interaction effects of childhood trauma and combat exposure on those associations among National Guard/reserve soldiers. Methods: Participants (N = 248) completed an electronic survey asking questions about their military experiences, physical and mental health, and substance use. Childhood trauma and combat exposure were examined jointly in regression models, controlling for age, marital satisfaction, and number of deployments. Results: Childhood trauma was associated with current drug use (trend level, odds ratio [OR] = 1.44, 95% confidence interval [CI]: 0.97, 2.14; P =.072) in the main effect model; however, there was not a significant interaction with combat. Combat exposure had a significant interaction with childhood trauma on alcohol problems (b = −0.56, 95% CI: −1.12, −0.01; P =.048), FHD (b = −0.27, 95% CI: −0.47, −0.08; P =.007), and lifetime drug use (OR = 1.78, 95% CI: 1.04, 3.04; P =.035). There were no associations with either of the trauma measures and current cigarette smoking. Conclusions: These results demonstrate that childhood and combat trauma have differential effects on alcohol use, such that combat trauma may not add to the effect on alcohol use in those with greater child maltreatment but may contribute to greater alcohol use among those with low child maltreatment. As expected, childhood and combat trauma had synergistic effects on lifetime drug use. Screening for multiple types of trauma prior to enlistment and/or deployment may help to identify at-risk individuals and allow time for early intervention to prevent future adverse outcomes.