Personality disorders and autism spectrum disorders: what are the connections?

BACKGROUND The relationship between autism spectrum disorders/pervasive developmental disorders and personality disorders is not completely clear, although both concepts imply lifelong impairment. The purpose of the present study was to investigate the presence of possible personality disorders in a group of young adults with Asperger syndrome. METHOD Fifty-four young adults with a clinical diagnosis of Asperger syndrome were assessed with Structured Clinical Interview for DSM-IV Axis II disorders to evaluate the presence of a concomitant personality disorder and completed the Autism Spectrum Quotient to measure level of autistic features. Autism spectrum diagnosis was confirmed by Diagnostic Interview for Social and Communication Disorders with a collateral informant. RESULTS Approximately half of the study group fulfilled criteria for a personality disorder, all belonging to cluster A or C. There was a significant difference across sex: men with Asperger syndrome meeting personality disorder criteria much more often than women with Asperger syndrome (65% vs 32%). Participants fulfilling criteria for a personality disorder showed more marked autistic features according to the Autism Spectrum Quotient. CONCLUSIONS There is a considerable overlap in symptoms between Asperger syndrome and certain personality disorders. Similarities and differences of the two concepts are discussed in the framework of the Diagnostic and Statistical Manual of Mental Disorders classification system.