Comparing the magnitude of improvement for patients with and without personality disorders in open-ended psychotherapy.

There is limited evidence that patients with a personality disorder (PD) have poorer psychotherapy outcomes compared to those without, but the majority of these studies are from short-term and symptom-focused interventions. In contrast, the present study provided open-ended psychotherapy to a sample of patients (N = 370), half of which had a PD a pretreatment. The results revealed that patients with PD demonstrated equal symptomatic improvement and greater interpersonal improvement than patients without PD. Similarly, observer-rated diagnostic changes were equivalent across the two groups. The PD group needed significantly higher therapy doses to reach this level of change. Both groups demonstrated enduring improvements when assessed at a 2.5-year follow-up. However, patients with a PD at pretreatment were more likely to relapse and regain their Axis I clinical disorder during follow-up. The degree of personality pathology was positively related to magnitude of change. (PsycInfo Database Record (c) 2021 APA, all rights reserved).