The Effect of Borderline Personality Pathology on Outcome of Cognitive Behavior Therapy.

Cognitive behavioral therapy (CBT) is an evidence-based psychotherapeutic approach which has been shown to be an effective intervention for most psychiatric disorders. There are conflicting data in the literature regarding whether a comorbid personality disorder worsens the prognosis of CBT for depression, anxiety, and other complaints. This study examined data collected before and after courses of CBT for patients with significant borderline (n=39, 11.5%) or obsessive-compulsive (n=66, 19.4%) personality pathology or no personality disorder (n=235, 69.1%). A diagnosis of personality pathology was not a significant predictor of outcome in CBT as measured by the reliable change index. However, patients with borderline personality pathology did demonstrate a greater response to CBT than other patients in terms of improvement on several measures of symptoms. Patients with borderline personality pathology appear to enter therapy with greater subjective depression and interpersonal difficulty than other patients but achieve larger gains during therapy. Implications and directions for future research are discussed.