Abstract: Posttraumatic stress disorder (PTSD) is a common psychiatric disorder following natural disasters. A growing number of studies have reported elevated prevalence and risk factors of PTSD among adolescent survivors of earthquake, flood and hurricane. Social supports and negative life events have been identified as important influence factors of adolescents’ posttraumatic stress disorder. Studies have documented that there are complex interplays among negative life events, social supports and mental health problems. The leading theoretical models of their relations include stress prevention model, support deterioration model, reciprocity of stress and perceived support model. The present study explored and compared these models of negative life events, social supports and posttraumatic stress symptoms in a large, prospective non-clinical sample of adolescents after the 2008 Wenchuan earthquake.
This study is a part of the longitudinal study of adolescents in Dujiangyan district after the 2008 Wenchuan earthquake in China. A total of 1573 adolescents were sampled from Dujiangyan district, 20 kilometer away from the epicenter. At the time of 6, 18, 24 months after the earthquake, participants were asked to complete questionnaires including Self-Rating Scale for Posttraumatic Stress Disorder, Adolescent Self-Rating Life Events Checklist, Social Support Rating Scale for Children and Adolescents, and demographics including sex, age, sibling, location, and earthquake exposure factors. One thousand and seventy-four adolescents were followed up all of the three waves. The mean age of the participants was 14.9 years (SD = 1.3) at wave 1, 42.4% were female, 30.9% resided in rural areas, and 83.2% were only child. Structural equation model was used to explore the causations of posttraumatic stress symptoms, social support and negative life events following the earthquake.
The results showed a moderate continuity of posttraumatic stress symptoms, negative life events, subjective social supports, objective social supports and utilization of social supports across the three waves (b = 0.39-0.57). Reciprocal relations were founded between posttraumatic stress symptoms and negative life events. To be specific, wave 1 posttraumatic stress symptoms positively predicted wave 2 negative life events (β = 0.16), wave 2 negative life events positively predicted wave 3 posttraumatic stress symptoms (β = 0.07); wave 1 negative life events positively predicted wave 2 posttraumatic stress symptoms (β = 0.07), wave 2 posttraumatic stress symptoms positively predicted wave 3 negative life events (β = 0.10). Subjective social supports and negative life events, objective social supports and negative life events also longitudinal predicted each other across waves. Specifically, wave 1 subjective social supports predicted wave 2 negative life events negatively (β = -0.11), wave 2 subjective social supports negatively predicted wave 3 negative life events (ß = -0.07), wave 1 negative life events predicted wave 2 subjective social supports negatively (β = -0.08), wave 2 negative life events negatively predicted wave 3 subjective social supports (β = -0.11); wave 1 negative life events predicted wave 2 objective social supports (β = -0.08) negatively, wave 1 objective social supports negatively predicted wave 2 negative life events (β = -0.06). In addition, wave 1 subjective social supports predicted wave 2 posttraumatic stress symptoms significantly (β = -0.07).
Posttraumatic stress symptoms, negative life events and social supports influence each other. Subjective social supports, objective social supports and utilization of social supports have characteristic relations with posttraumatic stress symptoms and negative life events. Posttraumatic stress symptoms and negative life events should be assessed and prevented timely. It would be effective and meaningful to guide the survival adolescents to perceive, construct, maintain, seek and utilize their social supports.

Key words: Wenchuan earthquake, survival adolescents, longitudinal study, posttraumatic stress symptoms