Obsessive-Compulsive Personality Disorder Symptom Stability in Individuals with Obsessive Compulsive Disorder over Six Years of Prospective Follow-up

Background: Obsessive-compulsive disorder (OCD) commonly co-occurs with personality disorders, particularly obsessive-compulsive personality disorder (OCPD). Recent research suggests that personality disorders, especially OCPD, might not be as stable as once thought. Thus, the current study aims to investigate the longitudinal stability of OCPD diagnosis and individual symptom criteria in individuals with OCD. Methods: 107 participants with a primary diagnosis of OCD were included in the study. Cochran’s Q tests were conducted to assess whether there were significant changes in the proportions of individuals endorsing an OCPD diagnosis and each of the eight OCPD symptom criteria across three time points over six years. Results: Although the percentage of participants diagnosed with OCPD remained consistent across the study, closer inspection of the data suggested diagnostic instability, with participants moving in and out of OCPD diagnosis. Five individual criteria (detail-oriented, reluctance to delegate, inflexible, overconscientious, and scrupulous, excessive work devotion, and miserly spending style) were shown to be stable and the other three (perfectionism, rigidity and stubbornness, and hoarding) were unstable. Conclusion: OCPD diagnosis is not stable in individuals with OCD and consists of a mix of enduring and episodic symptom criteria. It suggests the need for a potential refinement of OCPD diagnostic criteria and future research on symptom stability of OCPD across different diagnostic groups.