Patients with personality disorders and intellectual disability – closer to personality disorders or intellectual disability? A three-way comparison

Abstract

Within secure intellectual disability services, the prevalence of personality disorders is around 50%. Few studies have systematically examined how patients with both intellectual disability and personality disorders (the ID-PD group) differ from either those with a intellectual disability alone (the ID group) or those with a personality disorder alone (the PD group). The study groups were drawn from a database of 1182 discharges from secure hospital services in the UK and were compared on a number of pre and post treatment variables. Findings suggest that within the secure hospital system, those with intellectual disability alone and personality disorder alone are strikingly distinct on most of the examined parameters. The ID-PD group had higher scores on the PCL:SV and the HCR-20 than both the ID group and the PD group. In terms of outcomes, this group appeared to follow a path closer to those with intellectual disability.