The influence of PTSD symptoms on alcohol and drug problems: Internalizing and externalizing pathways.

Abstract

The present study used longitudinal data from a community study of familial alcoholism to examine the extent to which the long-term influence of posttraumatic stress disorder (PTSD) symptoms on future adult alcohol and drug problems was mediated by increases in early adult internalizing or externalizing symptoms. The subsample of participants included in this study were exposed to at least one traumatic event and had measures of both pre- and post-trauma functioning (n = 166; 62% men; 57% children of parents with an alcohol disorder; 68% non-Hispanic Caucasian, 26% Hispanic). The average age of participants was 13.1-year-old at the pre-trauma assessment, 20.3 years old at the early adult post-trauma assessment, and 25.7 years old at the adult follow-up assessment. Results from path analyses indicated that PTSD symptoms directly influenced risk for adult drug problems, but PTSD symptoms only influenced risk for adult alcohol problems to the extent that PTSD symptoms increased early adult externalizing symptomatology. Early adult internalizing symptomatology did not significantly mediate the influence of PTSD on either adult alcohol or drug problems. These findings suggest that the association between PTSD and future drug problems may be best explained by a PTSD-specific self-medication mechanism, whereas the association between PTSD symptoms and future alcohol problems may be best explained by an increased propensity to engage in externalizing behaviors. This study is among the first prospective, community-based studies to examine the risk mechanisms that link PTSD symptoms to alcohol and drug problems.