Differential outcomes of outpatient only versus combined inpatient/outpatient treatment in early intervention for adolescent borderline personality disorder.

Clinical guidelines for adults with borderline personality disorder (BPD) recommend outpatient psychotherapy as first-line treatment. Little is known whether this recommendation is also applicable to adolescents. The current study examined the relationship between treatment setting and the outcome of early intervention for adolescents with BPD pathology. One-hundred and seventy-eight adolescents from a specialized outpatient clinic were assessed at baseline, and at 1- and 2-year follow-up. Sixty-three participants who received inpatient treatment during the first year were assigned to the "combined inpatient/outpatient group", 115 participants to the "outpatient only group". Generalized linear and mixed models with inverted probability weights to adjust for baseline differences were applied to examine the impact of group on clinical changes over time. Both groups demonstrated a significant decrease in BPD features, depressive symptoms, psychopathological distress, non-suicidal self-injury (NSSI), suicidal thoughts, suicide attempts, and overall illness severity, and a significant increase in quality of life and psychosocial functioning from baseline to follow-up 2. The decrease in NSSI and overall illness severity, and the increase in psychosocial functioning from baseline to follow-up 1 were greater in the outpatient only group, with comparable improvements between groups from follow-up 1 to follow-up 2. Both outpatient treatment and combined outpatient/inpatient treatment resulted in clinical improvements over time, with some indication for faster changes in the outpatient only setting. The findings provide preliminary evidence that the recommendation of outpatient psychotherapy as the first-line treatment for BPD also holds true for adolescents.