Background: The evidence regarding whether co-morbid obsessive compulsive personality disorder (OCPD) is associated with treatment outcomes in obsessive compulsive disorder (OCD) is mixed, with some research indicating that OCPD is associated with poorer response, and some showing that it is associated with improved response. Aims: We sought to explore the role of OCPD diagnosis and the personality domain of conscientiousness on treatment outcomes for exposure and response prevention for OCD. Method: The impact of co-morbid OCPD and conscientiousness on treatment outcomes was examined in a clinical sample of 46 participants with OCD. Results: OCPD diagnosis and scores on conscientiousness were not associated with poorer post-treatment OCD severity, as indexed by Yale-Brown Obsessive Compulsive Scale (YBOCS) scores, although the relative sample size of OCPD was small and thus generalizability is limited. Conclusion: This study found no evidence that OCPD or conscientiousness were associated with treatment outcomes for OCD. Further research with larger clinical samples is required.

Background: It is often suggested that, in general, co-morbid personality disorders are likely to interfere with CBT based treatment of Axis I disorders, given that personality disorders are regarded as dispositional and are therefore considered less amenable to change than axis I psychiatric disorders. Aims: The present study aimed to investigate the impact of co-occurring obsessive-compulsive disorder (OCD) and obsessive-compulsive personality disorder (OCPD) on cognitive-behavioural treatment for OCD. Method: 92 individuals with a diagnosis of OCD participated in this study. Data were drawn from measures taken at initial assessment and following cognitive-behavioural treatment at a specialist treatment centre for anxiety disorders. Results: At assessment, participants with OCD and OCPD had greater overall OCD symptom severity, as well as doubting, ordering and hoarding symptoms relative to those without OCPD; however, participants with co-morbid OCD and OCPD demonstrated greater treatment gains in terms of OCD severity, checking and ordering than those without OCPD. Individuals with OCD and OCPD had higher levels of checking, ordering and overall OCD severity at initial assessment; however, at post-treatment they had similar scores to those without OCPD. Conclusion: The implications of these findings are discussed in the light of research on axis I and II co-morbidity and the impact of axis II disorders on treatment for axis I disorders.

Background: The value of defining subtypes in obsessive compulsive disorder (OCD) has become an important issue for recent debate. Probably the most robust example of subtyping is the identification of hoarding as being different both in terms of psychopathology and response to treatment. Aims: To identify differences in psychopathology and treatment response in OCD patients with and without additional hoarding symptoms. Method: Patients who had undertaken CBT for OCD were selected as falling into either a high or a low hoarding group. The high hoarding group (n = 18) was selected on the basis of a high score on the hoarding subscale of a self-report measure of OCD symptoms in addition to reaching clinician judged “threshold” on the hoarding item of the Obsessive Compulsive Personality Disorder (OCPD) SCID-II module. The low hoarding group (n = 20) was selected on the basis of a low score on the hoarding subscale and a clinician judgement that the hoarding item of the OCPD SCID-II module was “absent”. Results: On some measures of pre-treatment psychopathology, patients with OCD with hoarding symptoms were more severely affected than those without hoarding symptoms. It was found that there was no difference in eventual treatment outcome between the two groups, although there was some evidence that the hoarding group showed greater symptom decreases. Conclusions: The presence of hoarding symptoms does not negatively impact on the treatment of OCD.