Comparing the magnitude of improvement for patients with and without personality disorders in open-ended psychotherapy
Psychotherapy tends to produce meaningful and sustained positive changes for individuals suffering from a mental illness. A salient distinction can be made between patients with a Personality Disorder (PD) and those without. There is some evidence that patients with PD have poorer treatment outcomes, but the majority of these studies are from time-limited interventions that might be less suited for patients with PD. In contrast, the present study provided open-ended psychotherapy to a sample of patients (N = 370), half of which had at least one PD before treatment. The therapists received instruction to organize their treatments in cooperation with patients so that therapy was tailored to each patient’s individual needs and characteristics. The results revealed that patients with a PD demonstrated equal symptomatic improvement and greater interpersonal improvement compared to patients without a PD. Similarly, observer-rated diagnostic changes were equivalent across the two groups. Both groups demonstrated enduring improvements when assessed at a two-and-half-year follow-up. The degree of personality pathology was positively related to the magnitude of change, i.e. patients with more severe personality problems demonstrated greater gains in the open-ended treatment format.