Reciprocal associations between PTSD symptoms and alcohol involvement in college: a three-year trait-state-error analysis.

Bidirectional associations between posttraumatic stress disorder (PTSD) symptoms and alcohol involvement have been theorized, but have not been tested empirically. In this study, we examined these relations at the transition into and over the first 3 years of college by using an analytic approach (Trait-State-Error Modeling [TSE]; Kenny & Zautra, 1995) that allowed us to examine prospective, reciprocal associations among these constructs while accounting for intraindividual stability. Young adults (N = 486) were recruited at matriculation into college and assessed by Web survey in September of the first college year (T1) and 11 additional time points over 3 years. Findings showed evidence of prospective associations from alcohol involvement (both use and problems) to PTSD symptoms over the 3-year assessment period. We also observed prospective relations from PTSD symptoms to alcohol involvement over time. Patterns of covariation in trait vulnerability for alcohol involvement and PTSD symptoms differed from crossed-lagged associations among state-like variance in these constructs. Results suggest that PTSD symptoms and alcohol involvement each predict the other over the course of college. Findings also highlight the importance of considering both time-varying and stable sources of variation in these associations.