A Randomized Controlled Trial Comparing Mentalization‐Based Therapy With the Unified Protocol in the Treatment of Psychopathy and Comorbid Borderline + Antisocial Personality Disorders

ABSTRACT Background Those with cooccurring antisocial personality disorder (ASPD) and borderline personality disorder (BPD) are reported to be highly psychopathic and to represent a severe challenge to treatment efforts. In a sample of such individuals, the effects of two treatments, mentalization‐based therapy (MBT) and the unified protocol (UP), were investigated on three outcomes: (i) the psychopathy trait domains of meanness, boldness and disinhibition proposed by the triarchic psychopathy model (TPM); (ii) antisocial and borderline symptom severity; and (iii) the severity of their common features including impulsivity, anger expression and self‐harm. Methods Of 163 individuals with BPD + ASPD screened for eligibility, 55 were randomized to MBT treatment and 53 to UP treatment. Outcomes of treatment were assessed at 6‐month intervals to 36 months. Results Short‐term reductions were seen following both treatments in traits of psychopathy, antisocial and borderline personality symptom severity, anger dysregulation, impulsivity and self‐harm, but both treatment groups showed almost complete relapse of symptoms at the 36‐month follow‐up. UP had more durable effects than MBT. Conclusions Despite being a considerably shorter treatment, UP was at least as effective as MBT and in some respects superior. Remission of symptoms was not achieved by either treatment in the long term. Psychopathy and borderline/antisocial comorbidity with which it is associated are to some extent remediable through psychotherapy, but only in the short term. Clinical Implications Patients with high levels of impulsivity and disinhibition are likely to relapse following psychotherapy and should be closely monitored after treatment.