Societal cost-of-illness in patients with borderline personality disorder one year before, during and after dialectical behavior therapy in routine outpatient care

• DBT treatment was delivered in routine outpatient care.
• Direct and indirect costs were assessed from a societal perspective.
• Compared to pre-treatment, substantial savings in societal costs were found during DBT.
• Cost savings were mainly due to reduced hospitalization.
• During follow-up year, savings in societal costs were further extended.

Societal cost-of-illness in a German sample of patients with borderline personality disorder (BPD) was calculated for 12 months prior to an outpatient Dialectical Behavior Therapy (DBT) program, during a year of DBT in routine outpatient care and during a follow-up year. We retrospectively assessed resource consumption and productivity loss by means of a structured interview. Direct costs were calculated as opportunity costs and indirect costs were calculated according to the Human Capital Approach. All costs were expressed in Euros for the year 2010. Total mean annual BPD-related societal cost-of-illness was €28026 (SD = €33081) during pre-treatment, €18758 (SD = €19450) during the DBT treatment year for the 47 DBT treatment completers, and €14750 (SD = €18592) during the follow-up year for the 33 patients who participated in the final assessment. Cost savings were mainly due to marked reductions in inpatient treatment costs, while indirect costs barely decreased. In conclusion, our findings provide evidence that the treatment of BPD patients with an outpatient DBT program is associated with substantial overall cost savings. Already during the DBT treatment year, these savings clearly exceed the additional treatment costs of DBT and are further extended during the follow-up year. Correspondingly, outpatient DBT has the potential to be a cost-effective treatment for BPD patients. Efforts promoting its implementation in routine care should be undertaken.