Mindful Hypnotherapy for Cluster B Personality Disorders: A Randomized Controlled Trial with an Active Control

Cluster B personality disorders are characterized by pervasive emotional dysregulation and rigid interpersonal patterns, and they remain challenging to treat. Mindful hypnotherapy (MH), which integrates mindfulness and clinical hypnosis, may offer a transdiagnostic approach to cognitive and emotional inflexibility. This randomized controlled trial compared the efficacy of MH with an active control condition in reducing symptoms of Cluster B personality disorders. One hundred and twenty adults who met DSM-5 criteria for histrionic, narcissistic, antisocial, or borderline personality disorder were randomized to MH (n = 60) or an active control (n = 60) comprising selected cognitive behavioral therapy (CBT) and dialectical behavior therapy (DBT) skills. Both conditions consisted of eight weekly 60-minute individual sessions. Symptom severity was assessed pre- and post-treatment using the Millon Clinical Multiaxial Inventory-III (MCMI-III). Post-treatment scores on each Cluster B scale were compared between groups using ANCOVA, controlling for baseline values. Relative to the active control condition, MH produced significantly greater reductions in histrionic, narcissistic, and antisocial personality disorder symptoms (all p values < .05, partial η² ≈ .16-.21). No significant between-group difference emerged for borderline personality disorder symptoms (p = .31). MH appears to be an effective brief intervention for histrionic, narcissistic, and antisocial personality disorders when compared with an active CBT/DBT-based control condition. Its effects on borderline personality disorder remain inconclusive and warrant further investigation in longer and more intensive treatment protocols.