Long-term changes in the personality and psychopathological profile of opiate addicts after nucleus accumbens ablative surgery are associated with treatment outcome

Abstract

Objective: To investigate the long-term outcome and changes of the personality and psychopathological profile of opiate addicts after bilateral stereotactic nucleus accumbens (NAc) ablative surgery.

Methods: 60 patients were followed up for 5 years and abstinent status and adverse events were evaluated. NAc lesion volumes and locations were obtained by postoperative MRI scans. The Chinese version of the Eysenck Personality Questionnaire (EPQ-RSC), the Symptom Checklist-90-Revised (SCL-90-R), the Beck Depression Inventory (BDI), the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the World Health Organization's Quality of Life Questionnaire - Brief Version (WHOQOL-BREF) were administered to the patients before and 5 years after the stereotactic surgery.

Results: The total abstinence rate of all patients in their 5th postoperative year was 47.4%. The abstinent patients had a significantly larger lesion volume than the relapsed ones, but a larger lesion volume also increased the risk of adverse events. 5 years after surgery, the abstinent patients showed significant decreases on the Psychoticism (EPQ-P) and Neuroticism (EPQ-N) scores by EPQ-RSC, a significant decline on the Global Severity Index and the subscores in all 10 dimensions by SCL-90-R, significant decreases on the BDI and Y-BOCS scores, and significant improvements on the scores of all domains by WHOQOL-BREF, while for the relapsed patients, only the subscores of obsessive-compulsive by SCL-90-R and the Y-BOCS scores significantly decreased. Postoperative analysis revealed that the abstinent patients had a significantly better score than the relapsed ones by various instruments, and NAc lesion volumes and locations did not correlate with the outcome of any of these instruments.

Conclusion: The bilateral ablation of NAc by stereotactic neurosurgery was a feasible method for alleviating psychological dependence on opiate drugs and preventing a relapse. Long-term follow-up suggested that surgery can improve the personality and psychopathological profile of opiate addicts with a trend towards normal levels, provided persistent abstinence can be maintained; relapse, on the other hand, may ruin this effect.