A Randomized Blinded Trial of Nucleus Accumbens Ablation to Treat Opiate Dependence in Humans: Location Correlates with Outcome

Abstract

Introduction: Opiate addiction remains intractable in a large percentage of patients. Multiple studies identify a central role of the nucleus accumbens (NAc) in addiction; several studies note decreased addictive behavior after interventions in this brain area. In China, ablation of the NAc was common before November 2004, though it was poorly regulated. This study, a prospective randomized double-blinded trial carried out from January 2004 to November 2004, investigates the effect of different stereotactic lesions within NAc on opiate addiction to maximize benefit and minimize risk. Methods: 78 opiate-dependent patients were treated at the Tangdu Hospital Fourth Military Medical University during Jan. 2004 to Nov. 2004 with bilateral stereotactic radiofrequency lesioning of the posteromedial one third of NAc. Patients were randomly divided into four groups (A, B,C and D). Relative to the initial target, the lesion in Group A was enlarged laterally and superiorly, in Group B anteriorly and superiorly,and in Group C laterally and anteriorly. Among these three groups, the lesion volume was identical. In Group D, the lesion extended laterally and anteriorly and superiorly. Using opiate abstinence as the primary endpoint, four years of follow-up data for all patients regarding relapse and complications were collected. This trial is supplementarily registered with Current Controlled Trials, number ISRCTN33954423. Results: Four patients were withdrawn at the fourth year post-operation. For convenience of interpretation, this article appointed these patients as relapses. The overall abstinence rate was 53.8% (42/78). The abstinence rates of Group C (75.0%) and Group D (76.2%) were higher than Groups A (31.3%) and B (28.6%) (p<0.005). The neuropsychological adverse event rate was 24.3% (18/74) and did not differ statistically between the four groups. Conclusions: Although sometimes accompanied by neuropsychological adverse events, stereotactic ablation of NAc may effectively treat opiate addiction. Lesion location significantly impacts treatment efficacy. (Figure presented).