title: Recovery from post-traumatic stress disorder after a flood in China: a 13-year follow-up and its prediction by degree of collective action.
abstract: BACKGROUND
  Victims exposed to serious traumatic experiences may develop post-traumatic stress disorder (PTSD) and suffer this mental health problem for a long time. Different types of trauma displayed a chronicity rate of PTSD within the range of 6.3-68.9 %. As one of the most common and severe natural disasters, the natural progression of flood related PTSD has not been revealed. The aim of this study was to estimate the chronicity rate and identify the prognostic factors of PTSD in flood victims.
  
  
  METHODS
  Flood victims, who were over the age of 16 and diagnosed with PTSD in 2000 in Huarong, Ziyang, and Anxiang counties of Hunan province, China, were enrolled in this survey. Current probable PTSD was analyzed using the PTSD Checklist-Civilian version. Data were collected in face-to-face interviews and analyzed using univariate analysis and multiple logistic regression models.
  
  
  RESULTS
  The rate of current probable PTSD was 15.4 %. The current occurrences of re-experiencing, avoidance/numbing, and hyper-arousal symptom groups were 69.3 %, 17.2 %, and 50.2 %, respectively. Significant prognostic factors for current probable PTSD were flood-related stressors (e.g., life-threatening experiences, extreme physical adversity, and extreme psychological adversity) and frequency of general collective action. The relationships still existed when taking the fluctuation of frequency of general collective action into consideration. Gender and education level showed no influence on the recovery from PTSD. The impact of age in this study was inconsistent; in the 2000 model, around 2006 model, around 2013 model, and all FGCA model, older age was positive prognosis factor for PTSD; in the univariate analysis and fluctuation model, age showed no influence on the recovery from PTSD.
  
  
  CONCLUSIONS
  Our findings indicated that PTSD can persist 13 years after a flood. Demographic characteristics (e.g., age, gender, and education level) seem to have no influence on the recovery from PTSD. Trauma-related stressors and social participation are important predictors for remission from chronic PTSD.
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. 583534035@qq.com.
authors.forename: Shimin
authors.initials: S
authors.lastname: Hu
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. tanhz99@qq.com.
authors.forename: Hongzhuan
authors.initials: H
authors.lastname: Tan
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. rcreuben@yahoo.co.uk.
authors.forename: Reuben
authors.initials: R
authors.lastname: Cofie
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. zhoujia10@163.com.
authors.forename: Jia
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. 1064960669@qq.com.
authors.forename: Tubao
authors.initials: T
authors.lastname: Yang
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. 693583909@qq.com.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health of Central South University, 110 Xiangya Road, Changsha, Hunan, 410007, PR China. lazroy@live.cn.
authors.forename: Aizhong
authors.initials: A
authors.lastname: Liu
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D002908:Chronic Disease; D004190:Disasters; D005260:Female; D055868:Floods; D005500:Follow-Up Studies; D006801:Humans; D007407:Interviews as Topic; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D012959:Socioeconomic Factors; D013313:Stress Disorders, Post-Traumatic / Q000453:epidemiology* / Q000523:psychology