Epidemiology and presentation of post-traumatic disorders

Abstract

The history of trauma research is a relatively short one, dating back to the introduction of post-traumatic stress disorder (PTSD) into the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) in 1980. Whilst the introduction of PTSD has provided a major impetus for the scientific investigations of post-traumatic conditions in a variety of samples, fewer epidemiological studies have been conducted in the general population for both adults and children. Large differences in the lifetime prevalence rates reported for adult exposure to traumatic events (3.9–89.6%) as well as for PTSD (1.0–11.2%) have been observed owing to variations in the design, sampling strategies, and method of diagnostic assessments used. Despite these differences, however, several consistent findings have emerged, although it remains unclear to what extent the outcome of population-based surveys conducted predominantly in the USA can be generalized to other countries. Similarly, disasters occur in a wide variety of settings and circumstances, thereby introducing a number of methodological challenges that may deviate substantially from those commonly used in traditional epidemiological studies. Systematic reviews of the disaster literature based on meta-analyses have sought to address these limitations. A similar approach has been applied to the identification of vulnerability factors for PTSD in trauma-exposed adults to establish why considerable individual differences exist. Such knowledge is imperative to inform the selective use of interventions. We still await a better understanding of why some individuals display positive changes after trauma, given evidence of resilience in the face of even the most severe stressor.