Posttraumatic Stress Disorder among Survivors 8 Months and 3 Years after Sichuan 2008 Earthquake in China

OBJECTIVE: This retrospective analysis aimed to report the prevalence of posttraumatic stress disorder (PTSD) at eight months and three years post 2008 earthquake in Sichuan province of China and to examine risk factors of PTSD among survivors at eight months post-earthquake. METHODS: A two-wave longitudinal survey study with a multistage cluster sampling method was conducted. A total of 1441 survivors aged between 16 and 89 years were interviewed at 8 months post-earthquake (i.e. first wave). The second wave was conducted at three years post-earthquake with 332 respondents who were randomly selected from the original cohort. PTSD was defined if the total score of PTSD self-rating scale (PTSD-SS) >50. Student's T-test was used to compare PTSD-SS scores at eight months and three years. Multivariate logistic regression analyses were used to evaluate risk factors of PTSD in the first wave. RESULTS: The rates of PTSD at eight months and at three years were 58.36% and 16.10% respectively (p<0.001). The average PTSD total scores (SD) at eight months and three years were 56.48 (20.66) and 45.50 (18.35), respectively (p<0.001). Statistically significant risk factors of PTSD in the first wave included age (odds ratio (OR=1.02, 95% confidence interval (CI) =1.01-1.03), body injury (OR=2.44, 95% CI=1.54-3.85) and self-assessment of psychological trauma (OR=1.15, 95% CI=1.10-1.22). Social support was a protective factor of PTSD (OR=0.47, 95% CI=0.37-0.59). CONCLUSIONS: PTSD declined and resolved largely over time. Post-disaster recovery interventions should focus on those with risk factors such as the elderly, self-assessed traumatic, and those lacking social support.