Longitudinal examination of PTSD symptoms and problematic alcohol use as risk factors for adolescent victimization

Abstract

The current study examined associations between posttraumatic stress disorder (PTSD) symptoms and future interpersonal victimization among adolescents, after accounting for the impact of early victimization exposure, gender, ethnicity, and household income. In addition, problematic alcohol use was tested as a mediator of the relation between PTSD symptoms and subsequent victimization. Participants included a national longitudinal sample of adolescents (N = 3,604) who were ages 12 to 17 at the initial assessment: 50% were male, and 67% were White, 16% African American, and 12% Hispanic. Cohort-sequential latent growth curve modeling was used to examine associations among the study variables. Baseline PTSD symptoms significantly predicted age-related increases in interpersonal victimization, even after accounting for the effects of earlier victimization experiences. In addition, alcohol problems emerged as a partial mediator of this relation, such that one fourth to one third of the effect of PTSD symptoms on future victimization was attributable to the impact of PTSD symptoms on alcohol problems (which, in turn, predicted additional victimization risk). Collectively, the full model accounted for more than half of the variance in age-related increases in interpersonal victimization among youth. Results indicate that PTSD symptoms serve as a risk factor for subsequent victimization among adolescents, over and above the risk conferred by prior victimization. This increased risk occurred both independently and through the impact of PTSD symptoms on problematic alcohol use. Based on these findings, it is hypothesized that the likelihood of repeated victimization among youth might be reduced through early detection and treatment of these clinical problems.

Figure 1

Cohort-sequential latent growth curve model for PTSD symptoms. Variables represent baseline symptom levels at age 13 (intercept) and age-related increases from 13 to 19 (slope). Solid age boxes represent collected data, whereas dashed lines reflect data missing by design. Asterisks indicate that pathways were allowed to vary freely, with the exception that regression weights at each age are equal across cohorts. An identical procedure was used to model the alcohol problems and interpersonal victimization variables. Cov = covariance; D = variance; M = mean; y.o. = year-old.

Figure 2

Results of the (a) Tier II and (b) Tier III models. PTSD symptoms and interpersonal victimization are modeled in Tier II (Figure 2a). Alcohol problems were added as a potential mediator of these relations in Tier III, and are shown in grey font (Figure 2b). Variables represent baseline symptom levels at age 13 (intercept) and age-related increases from 13 to 19 (slope). Single-headed arrow values reflect standardized β-weights; double-headed arrow values reflect correlations (r). Regression pathways for both models are all significant at p ≤ .002. Gender, ethnicity, and household income are included in both models but not depicted for readability.

Figure 3

Cohort-sequentially modeled age-related changes in mean number of items endorsed for PTSD symptoms (squares), interpersonal victimization (diamonds), and alcohol problems (triangles). Error bars reflect standard error.