Comorbid obsessive–compulsive personality disorder in obsessive–compulsive disorder (OCD): A marker of severity

IntroductionComorbid obsessive–compulsive personality disorder (OCPD) is well-described in obsessive–compulsive disorder (OCD). It remains unclear, however, whether OCPD in OCD represents a distinct subtype of OCD or whether it is simply a marker of severity in OCD.Materials and methodsThe aim of this study was to compare a large sample of OCD subjects (n = 403) with and without OCPD on a range of demographic, clinical and genetic characteristics to evaluate whether comorbid OCPD in OCD represents a distinct subtype of OCD, or is a marker of severity.ResultsOur findings suggest that OCD with and without OCPD are similar in terms of gender distribution and age at onset of OC symptoms. Compared to OCD − OCPD (n = 267, 66%), those with OCD + OCPD (n = 136, 34%) are more likely to present with the OC symptom dimensions which reflect the diagnostic criteria for OCPD (e.g. hoarding), and have significantly greater OCD severity, comorbidity, functional impairment, and poorer insight. Furthermore there are no differences in distribution of gene variants, or response to treatment in the two groups.ConclusionThe majority of our findings suggest that in OCD, patients with OCPD do not have a highly distinctive phenomenological or genetic profile, but rather that OCPD represents a marker of severity.

Research highlights
► Comorbid obsessive–compulsive personality disorder (OCPD) is well-described in obsessive–compulsive disorder (OCD).
► In OCD, patients with OCPD do not have a highly distinctive phenomenological or genetic profile.
► In OCD, comorbid OCPD represents a marker of severity.