The Mediating Role of Misinterpretations and Neutralizing Responses to Unwanted Intrusive Thoughts in Obsessive-Compulsive Spectrum Disorders.

Background. Cognitive-behavioral theories suggest that obsessions in obsessive-compulsive disorder (OCD) develop from maladaptive misinterpretations and coping strategies of unwanted intrusive thoughts (UITs). Models of Body Dysmorphic Disorder (BDD) and Illness Anxiety Disorder (IAD) propose that these symptoms stem from similar misinterpretations of common UITs relating to perceived defects in appearance and illness. This study examines whether maladaptive misinterpretations and control strategies leading to the escalation of obsessional UITs to OCD symptoms also have a similar effect on the development of BDD and IAD. More specifically, we examined whether misinterpretations and neutralizing responses mediate the associations between the frequency of disorder-specific UITs and symptoms of these disorders. Method. A total of 625 non-clinical participants from four countries completed the Questionnaire of Unpleasant Intrusive Thoughts (QUIT) that assesses OCD, BDD and IAD-related UITs and their associated misinterpretations and neutralizing strategies, as well as self-report measures of OCD, BDD, and IAD symptoms. Parallel multiple mediation models were conducted. Results. The frequency of OCD, BDD and IAD-related UITs predicted symptoms of each disorder. Dysfunctional appraisals and neutralizing behaviors mediated the associations between disorder-specific UITs and symptoms in OCD and IAD. The IAD model accounted for a smaller proportion of variance than the OCD model. No mediating effects were found for BDD symptoms. Conclusions. Experiencing disturbing UITs is a transdiagnostic risk factor of OCD, BDD and IAD, and is associated with symptoms of these disorders. Maladaptive interpretation of UITs and neutralizing strategies should be specific targets in the assessment and treatment of OCD and IAD. The absence of mediation effects for BDD could be due to the limitations observed on the self-report used to assess BDD symptoms and/or the low relevance of the misinterpretations and control strategies assessed by the QUIT, which are more typically endorsed by individuals with OCD.