Deep Brain Stimulation for Addiction Treatment: Further Considerations on Scientific and Ethical Issues

Deep Brain Stimulation for Addictive Disorders-Where Are We Now?

In the face of a global epidemic of drug addiction, neglecting to develop new effective therapies will perpetuate the staggering human and economic costs of substance use. This review aims to summarize and evaluate the preclinical and clinical studies of deep brain stimulation (DBS) as a novel therapy for refractory addiction, in hopes to engage and inform future research in this promising novel treatment avenue. An electronic database search (MEDLINE, EMBASE, Cochrane library) was performed using keywords and predefined inclusion criteria between 1974 and 6/18/2021 (registered on Open Science Registry). Selected articles were reviewed in full text and key details were summarized and analyzed to understand DBS' therapeutic potential and possible mechanisms of action. The search yielded 25 animal and 22 human studies. Animal studies showed that DBS of targets such as nucleus accumbens (NAc), insula, and subthalamic nucleus reduces drug use and seeking. All human studies were case series/reports (level 4/5 evidence), mostly targeting the NAc with generally positive outcomes. From the limited evidence in the literature, DBS, particularly of the NAc, appears to be a reasonable last resort option for refractory addictive disorders. We propose that future research in objective electrophysiological (e.g., local field potentials) and neurochemical (e.g., extracellular dopamine levels) biomarkers would assist monitoring the progress of treatment and developing a closed-loop DBS system. Preclinical literature also highlighted the prefrontal cortex as a promising DBS target, which should be explored in human research.

Clinical evaluation of deep brain stimulation of nucleus accumbens/anterior limb of internal capsule for opioid relapse prevention: protocol of a multicentre, prospective and double-blinded study

INTRODUCTION

Deep brain stimulation (DBS) is a new potential surgical treatment for opioid dependence. However, the implement of DBS treatment in addicted patients is currently controversial due to the significant associated risks. The aim of this study was mainly to investigate the therapeutic efficacy and safety of bilateral DBS of nucleus accumbens and the anterior limb of the internal capsule (NAc/ALIC-DBS) in patients with refractory opioid dependence (ROD).

METHODS AND ANALYSIS

60 patients with ROD will be enrolled in this multicentre, prospective, double-blinded study, and will be followed up for 25 weeks (6 months) after surgery. Patients with ROD (semisynthetic opioids) who meet the criteria for NAc/ALIC-DBS surgery will be allocated to either the early stimulation group or the late stimulation group (control group) based on the randomised ID number. The primary outcome was defined as the abstinence rate at 25 weeks after DBS stimulation on, which will be confirmed by an opiate urine tests. The secondary outcomes include changes in the Visual Analogue Scale (VAS) score for craving for opioid drugs, body weight, as well as psychological evaluation measured using the 17-item Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, the Pittsburgh Sleep Quality Index, Fagerstrom test for nicotine dependence assessment, social disability screening schedule, the Activity of Daily Living Scale, the 36-item Short Form-Health Survey and safety profiles of both groups.

ETHICS AND DISSEMINATION

The study received ethical approval from the medical ethical committee of Tangdu Hospital, The Fourth Military Medical University, Xi'an, China. The results of this study will be published in a peer-reviewed journal and presented at international conferences.

TRIAL REGISTRATION NUMBER

NCT03424616; Pre-results.