BACKGROUND: Previous studies suggested an association between exposure to trauma or stressful life events and obsessive-compulsive disorder (OCD). This study investigates the hypothesis that traumatic events and posttraumatic stress disorders (PTSD) precede the onset of OCD. SAMPLING AND METHODS: 210 cases with OCD from university treatment facilities were compared with 133 sex- and age-matched controls from the adult general population. The data were derived from a German family study on OCD (GENOS). Direct interviews were carried out with the German version of the Schedule for Affective Disorders and Schizophrenia - Lifetime Version for Anxiety Disorders (DSM-IV). RESULTS: Severe traumatization occurred in 6.2% of the OCD cases and in 8.3% of the controls. The lifetime prevalence rates of traumatization, PTSD and acute stress disorder were not different between the subjects with OCD and controls (p > 0.05). In 6 cases, acute stress disorder, subclinical or full PTSD preceded the onset of OCD, in 3 cases the trauma-related disorders and OCD occurred within the same year, in 5 other cases, the trauma-related disorders started after the onset of OCD. CONCLUSION: There is no significant association of traumatization or PTSD with OCD compared with controls. Given the low rate of trauma-related disorders occurring before (2.9%) or within (1.5%) the same year as the onset of OCD other factors than severe traumatic events determine the onset of OCD in most of the cases.
