Societal costs of personality disorders among treatment-seeking patients in Norway: the relative contribution of specific DSM-5 categories.

Personality disorders (PDs) are associated with high levels of societal costs, regardless of whether a single PD or a broad range of PDs have been studied. However, research on the relative contribution of specific PD-types on societal costs is limited. The aim of this study was to explore the possible contributions of the individual DSM-5 categories of PDs on the level of societal costs and its components (health service costs and productivity loss), while controlling for the impact of comorbid mental health and substance use disorders on these outcomes. Participants (n = 798) were retrieved from the quality register of the Norwegian Network for Personality Disorders-a collaboration of PD-treatment units within specialist mental health services. The patients were referred to treatment in the time-period 2017-2020. Costs were assessed using a structured interview covering the 6-month period prior to assessment. Diagnoses were determined by semi-structured diagnostic interviews (SCID-5-PD and M.I.N.I.). Statistics included multiple regression analyses. The main result was that no specific PD had a unique contribution to the high level of societal costs generally found among treatment-seeking patients with PDs. Borderline PD (BPD) was the only PD with significantly higher health service costs than the other PDs, while BPD, avoidant PD, and unspecified PD were independently associated with enhanced productivity loss. The differential cost-effects of specific PDs on the cost components were small. Several comorbid mental health and substance use disorders were significant contributors to costs, irrespective of PD status. The results underscore the importance of developing and implementing effective treatments for a broader range of PDs, to reduce the high levels of societal costs associated with all PDs.