Association of DSM-IV Posttraumatic Stress Disorder With Traumatic Experience Type and History in the World Health Organization World Mental Health Surveys

Importance: Previous research has documented significant variation in post-traumatic stress disorder (PTSD) prevalence depending on type of traumatic experience (TE) and prior history of TE exposure, but the relatively small sample sizes in these studies resulted in a number of unresolved basic questions. Objective: To examine disaggregated associations of TE type-history with PTSD in a large cross-national community epidemiological dataset. Design/Setting/Participants/Exposures: The WHO World Mental Health Surveys assessed 29 TE types (lifetime exposure, age of first exposure) along with DSM-IV PTSD associated with one randomly-selected TE exposure (the random TE) for each respondent. Surveys were carried out in 20 countries (n=34,676 respondents). Main outcome: PTSD assessed with the Composite International Diagnostic Interview (CIDI). Results: Lifetime TE exposure was reported by 70.3% of respondents (Mean=4.5 exposures among respondents with any). Weighted (by TE frequency) prevalence of PTSD associated with random TEs was 4.0%. Odds-ratios (ORs) of PTSD were elevated for TEs involving sexual violence (OR,2.7) and witnessing atrocities (OR,4.2). Prior exposure to some, but not all, same-type TEs predicted either increased vulnerability (physical assault; OR,3.2) or resilience (participation in sectarian violence; OR,0.3) to PTSD after the random TE. We replicated the finding of earlier studies that more general history of TE exposure predicted increased vulnerability to PTSD across the full range of random TE types, but this generalized vulnerability was limited to prior TEs involving violence (participation in organized violence, physical violence victimization, sexual violence victimization; OR,1.3-2.5). Conclusions/Relevance: The WMH findings advance understanding of the extent to which PTSD risk varies with type of TE and history of prior TE exposure. We refined previous findings about the elevated PTSD risk associated with TEs involving assaultive violence by showing that this was true only for repeat occurrences. We also found that some types of prior TE exposures are associated with increased resilience rather than increased vulnerability, connecting the literature on TE history with the literature on resilience after adversity. Although leaving many questions unresolved about causal pathways and mechanisms, these results are valuable in providing an empirical rationale for more focused investigations of these specifications in future studies.