Background: Whereas the phenomenology of obsessive-compulsive personality disorder (OCPD) shows similarities to that of obsessive compulsive and related disorders (OCRDs) as well as with autism spectrum disorder (ASD), the relationship between these disorders is poorly understood.Aims: Within a clinical sample, we aimed to investigate the distribution of OCD, OCPD and ASD symptoms and traits and their interrelationship, as well as to evaluate insight and treatment refractoriness.Methods: Consecutive adult OCD outpatients were assessed for OCPD traits (Compulsive Personality Assessment Scale (CPAS)), OCD symptoms (Yale-Brown Obsessive Compulsive Scale (Y-BOCS)), ASD traits (Autism Spectrum Quotient (AQ)), insight (Brown Assessment of Beliefs Scale (BABS)) and treatment resistance (clinical records). Those scoring highly on the AQ underwent a diagnostic interview for ASD.Results: Sixty-seven consenting individuals completed the CPAS, BABS and AQ, and 65 completed the Y-BOCS. Twenty-four patients (35.8%) were diagnosed with OCPD. Patients with OCPD were less likely to be employed (p=.04). They demonstrated elevated AQ scores (p=.004) and rates of ASD diagnosis (54.2%) (p <.001). OCPD traits (CPAS) showed a highly significant correlation with ASD traits (AQ) (p<.001), and no association with Y-BOCS, BABS or treatment resistance.Conclusions: In an OCD cohort limited by small size, OCPD associated strongly with unemployment and ASD, with implications for diagnosis, treatment and outcome.KEY POINTSClinicians should exercise a high level of vigilance for OCPD and ASD in patients presenting with obsessive compulsive symptoms.The presence of OCPD may indicate a likelihood of disabling ASD traits, including cognitive inflexibility, poor central coherence and poor social communication.These neuropsychological factors may require separate clinical intervention strategies.
Keywords: Obsessive compulsive personality disorder; autism spectrum disorders; co-morbidity; obsessive compulsive disorder; obsessive–compulsive and related disorders.