Identify Delayed Trajectory from Resilience Trajectory in Trauma Exposed Youths: the Role of Different PTSD Dimensions.

A subset of trauma-exposed youth follows a "delayed" posttraumatic stress disorder (PTSD) trajectory, where initially low symptoms escalate over time. This pattern poses a significant clinical challenge as these individuals resemble the resilient group and are often missed by early screening, requiring sensitive identification. This study aimed to identify youth on delayed versus resilience trajectories using specific symptom dimensions from the refined 8-factor model of DSM-5 PTSD symptoms. 659 middle-school students exposed to a major chemical explosion accident were assessed at 4, 8, and 13 months post-trauma using the PTSD Checklist-5. First, latent class growth analysis identified four distinct trajectories, including delayed and resilience trajectories. Second, using baseline demographics and eight symptom dimensions, logistic regression predicted the odds of membership in the delayed trajectory (vs. resilience). The primary model (dichotomous predictors) found female gender (OR = 2.38), internally-cued intrusions (OR = 2.77), dysphoric arousal (OR = 2.61), and anxious arousal (OR = 2.77) were significant predictors. A subsequent sensitivity analysis (continuous scores) confirmed internally-cued intrusions and anxious arousal as robust predictors but revealed that the gender effect was no longer significant. Our results suggest that current severity-based screening can be enhanced by incorporating profile-based approaches. Internally-cued intrusions and anxious arousal are potent early predictors for the delayed trajectory, even among individuals with low total symptom scores. Our findings highlight the need for integrating profile-based strategies into early identification and targeted prevention, while the role of gender in this process warrants further investigation.