Epidemiological aspects of obsessive-compulsive disorder in community adolescents and young adults: subsequent psychopathology and risk factors

Obsessive-compulsive disorder (OCD) is associated with severe interference in social and
occupational functioning, quality of life, and substantial comorbidity. Improved knowledge of risk factors for OCD and pathways to subsequent mental disorders could set the stage for successfully preventing OCD and the progression of psychopathology. Thus, the aim of this thesis was to examine (1) whether OCD predicts the subsequent onset of various mental disorders and (2) whether certain risk factors, that is, behavioral inhibition (BI), parental rearing, and adverse life events and the interaction thereof, are associated with an increased risk of OCD. A representative community sample of 3,021 adolescents and young adults was prospectively followed for up to 10 years. DSM-IV OCD, other mental disorders, and adverse life events were assessed using the DIA-X/M-CIDI. Parental rearing and BI (social and nonsocial fear components) were assessed with self-report questionnaires. OCD was associated with the subsequent onset of social phobia, generalized anxiety disorder (GAD), bipolar disorder (BIP), dysthymia, and bulimia nervosa. Total BI, both its components, and paternal rejection were found to increase the risk of OCD. Components of BI moderated the effect of adverse life events and paternal rearing on OCD. Maternal and paternal emotional warmth moderated the association between adverse life events and OCD. The findings indicate that interventions for individuals with OCD are important to prevent the subsequent onset of internalizing disorders. Further research is required to fully understand the underlying mechanisms. Knowledge of the demonstrated risk factors and moderators might inform future prevention efforts for OCD. Results emphasize the need to investigate (1) whether early treatment of OCD reduces the risk of subsequent psychopathology and (2) the effectiveness of prevention programs that target individuals at high risk of OCD.