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

A protocol of a systematic review on deep brain stimulation surgery and its efficacy in addressing substance abuse addiction

Background

Pharmacotherapy and psychotherapeutic approaches are still the mainstay first line of treatment for substance use disorder. However, the path to rehabilitation and cessation of dependence often proves uncertain and laborious, with risks of relapse being considerable despite exposure to current therapeutic modalities. For cases of treatment-refractory addiction, deep brain stimulation (DBS) interventions can prove a more effective long term therapeutic solution for the patient.

Objectives

The aim of the study will be to systematically assess whether attempts at correcting substance use disorder via DBS neurosurgical interventions have been successful in inducing remission or ameliorating relapse rates.

Methods

The current study will analyze available literature from database inception up to 15th April 2023, reviewing all publications documenting results achieved with human patients undergoing DBS for substance use disorder in PubMed, Ovid, Cochrane, and Web of Science. The electronic database search will exclude animal studies in the field and focus solely on the application of DBS for the purposes of addressing addiction disorders.

Results

The expectation is for a reduced number of trial results to have been reported, namely due to the relatively recent application of DBS to address severe addiction. Nonetheless, numbers should be in sufficient amount to inform about the efficacy of the intervention.

Conclusion

This study will attempt to demonstrate the viability of DBS as a solution for tackling treatment-refractory substance use disorder, proposing it as a valid therapeutic option that can deliver robust results and help combat an expanding societal plague that is drug dependence.

Deep Brain Stimulation for Substance Use Disorders? An Exploratory Qualitative Study of Perspectives of People Currently in Treatment

OBJECTIVE

Although previous studies have discussed the promise of deep brain stimulation (DBS) as a possible treatment for substance use disorders (SUDs) and collected researcher perspectives on possible ethical issues surrounding it, none have consulted people with SUDs themselves. We addressed this gap by interviewing people with SUDs.

METHODS

Participants viewed a short video introducing DBS, followed by a 1.5-hour semistructured interview on their experiences with SUDs and their perspective on DBS as a possible treatment option. Interviews were analyzed by multiple coders who iteratively identified salient themes.

RESULTS

We interviewed 20 people in 12-step-based, inpatient treatment programs (10 [50%] White/Caucasian, 7 Black/African American [35%], 2 Asian [10%], 1 Hispanic/Latino [5%], and 1 [5%] Alaska Native/American Indian; 9 women [45%], 11 men [55%]). Interviewees described a variety of barriers they currently faced through the course of their disease that mirrored barriers often associated with DBS (stigma, invasiveness, maintenance burdens, privacy risks) and thus made them more open to the possibility of DBS as a future treatment option.

CONCLUSIONS

Individuals with SUDs gave relatively less weight to surgical risks and clinical burdens associated with DBS than previous surveys of provider attitudes anticipated. These differences derived largely from their experiences living with an often-fatal disease and encountering limitations of current treatment options. These findings support the study of DBS as a treatment option for SUDs, with extensive input from people with SUDs and advocates.

Oxycodone-induced dopaminergic and respiratory effects are modulated by deep brain stimulation

Introduction: Opioids are the leading cause of overdose death in the United States, accounting for almost 70,000 deaths in 2020. Deep brain stimulation (DBS) is a promising new treatment for substance use disorders. Here, we hypothesized that VTA DBS would modulate both the dopaminergic and respiratory effect of oxycodone. Methods: Multiple-cyclic square wave voltammetry (M-CSWV) was used to investigate how deep brain stimulation (130 Hz, 0.2 ms, and 0.2 mA) of the rodent ventral segmental area (VTA), which contains abundant dopaminergic neurons, modulates the acute effects of oxycodone administration (2.5 mg/kg, i.v.) on nucleus accumbens core (NAcc) tonic extracellular dopamine levels and respiratory rate in urethane-anesthetized rats (1.5 g/kg, i.p.). Results: I.V. administration of oxycodone resulted in an increase in NAcc tonic dopamine levels (296.9 ± 37.0 nM) compared to baseline (150.7 ± 15.5 nM) and saline administration (152.0 ± 16.1 nM) (296.9 ± 37.0 vs. 150.7 ± 15.5 vs. 152.0 ± 16.1, respectively, p = 0.022, n = 5). This robust oxycodone-induced increase in NAcc dopamine concentration was associated with a sharp reduction in respiratory rate (111.7 ± 2.6 min-1 vs. 67.9 ± 8.3 min-1; pre- vs. post-oxycodone; p < 0.001). Continuous DBS targeted at the VTA (n = 5) reduced baseline dopamine levels, attenuated the oxycodone-induced increase in dopamine levels to (+39.0% vs. +95%), and respiratory depression (121.5 ± 6.7 min-1 vs. 105.2 ± 4.1 min-1; pre- vs. post-oxycodone; p = 0.072). Discussion: Here we demonstrated VTA DBS alleviates oxycodone-induced increases in NAcc dopamine levels and reverses respiratory suppression. These results support the possibility of using neuromodulation technology for treatment of drug addiction.

Modern neurosurgical techniques for psychiatric disorders

Psychosurgery refers to an ensemble of more or less invasive techniques designed to reduce the burden caused by psychiatric diseases in patients who have failed to respond to conventional therapy. While most surgeries are designed to correct apparent anatomical abnormalities, no discrete cerebral anatomical lesion is evident in most psychiatric diseases amenable to invasive interventions. Finding the optimal surgical targets in mental illness is troublesome. In general, contemporary psychosurgical procedures can be classified into one of two primary modalities: lesioning and stimulation procedures. The first group is divided into (a) thermocoagulation and (b) stereotactic radiosurgery or recently introduced transcranial magnetic resonance-guided focused ultrasound, whereas stimulation techniques mainly include deep brain stimulation (DBS), cortical stimulation, and the vagus nerve stimulation. The most studied psychiatric diseases amenable to psychosurgical interventions are severe treatment-resistant major depressive disorder, obsessive-compulsive disorder, Tourette syndrome, anorexia nervosa, schizophrenia, and substance use disorder. Furthermore, modern neuroimaging techniques spurred the interest of clinicians to identify cerebral regions amenable to be manipulated to control psychiatric symptoms. On this way, the concept of a multi-nodal network need to be embraced, enticing the collaboration of psychiatrists, psychologists, neurologists and neurosurgeons participating in multidisciplinary groups, conducting well-designed clinical trials.

New Frontiers for Deep Brain Stimulation: Directionality, Sensing Technologies, Remote Programming, Robotic Stereotactic Assistance, Asleep Procedures, and Connectomics

Over the last few years, while expanding its clinical indications from movement disorders to epilepsy and psychiatry, the field of deep brain stimulation (DBS) has seen significant innovations. Hardware developments have introduced directional leads to stimulate specific brain targets and sensing electrodes to determine optimal settings via feedback from local field potentials. In addition, variable-frequency stimulation and asynchronous high-frequency pulse trains have introduced new programming paradigms to efficiently desynchronize pathological neural circuitry and regulate dysfunctional brain networks not responsive to conventional settings. Overall, these innovations have provided clinicians with more anatomically accurate programming and closed-looped feedback to identify optimal strategies for neuromodulation. Simultaneously, software developments have simplified programming algorithms, introduced platforms for DBS remote management via telemedicine, and tools for estimating the volume of tissue activated within and outside the DBS targets. Finally, the surgical accuracy has improved thanks to intraoperative magnetic resonance or computerized tomography guidance, network-based imaging for DBS planning and targeting, and robotic-assisted surgery for ultra-accurate, millimetric lead placement. These technological and imaging advances have collectively optimized DBS outcomes and allowed “asleep” DBS procedures. Still, the short- and long-term outcomes of different implantable devices, surgical techniques, and asleep vs. awake procedures remain to be clarified. This expert review summarizes and critically discusses these recent innovations and their potential impact on the DBS field.

Effect of multidimensional comprehensive intervention on medication compliance, social function and incidence of MACE in patients undergoing PCI

OBJECTIVE

To analyze the effect of multidimensional comprehensive intervention on medication compliance, social function and incidence of major adverse cardiovascular events (MACE) in patients undergoing percutaneous coronary intervention (PCI).

METHODS

Ninety-eight patients with coronary heart disease (CHD) who underwent PCI in our hospital were selected and divided into the regular group (n=46, receiving regular nursing intervention) and the comprehensive group (n=52, receiving multidimensional comprehensive nursing intervention) according to the different nursing intervention methods. The medication compliance, social function, quality of life, and incidence of MACE were compared between the two groups.

RESULTS

The comprehensive group showed significantly higher rates of taking medication on time, taking medication according to the proper amount, taking medication at the recomended times, no increase or decrease in the amount of medication, and taking medication without interruption than the regular group (P < 0.05). The comprehensive group exhibited significantly higher scores of medication compliance than the regular group (P < 0.05). The Social Disability Screening Schedule (SDSS) scores of both groups during intervention for 8 weeks were lower than those before intervention and after intervention for 2 and 4 weeks (P < 0.05). The SDSS scores of intervention for 2, 4, and 8 weeks in the comprehensive group were significantly lower than that in the regular group (P < 0.05). After intervention, the comprehensive group showed significantly higher scores of physiological function, psychological function, cognitive function, emotional function, role function, and total quality of life than the regular group (P < 0.05). The incidence of MACE in the comprehensive group was significantly lower than that in the regular group (P < 0.05).

CONCLUSION

The use of multidimensional comprehensive intervention for patients undergoing PCI can effectively improve patients' medication compliance, social function and quality of life, and reduce the incidence of MACE.

Endogenous opiates and behavior: 2019

This paper is the forty-second consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2019 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Safety and Feasibility of Nucleus Accumbens Surgery for Drug Addiction: A Systematic Review

BACKGROUND

Substance addiction encompasses the incapacity to discontinue urgent drug use; many severely disabled patients might be considered appropriate candidates for surgery due to the high rates of relapse despite conservative treatment. A crucial finding in the brain of these patients is increased extracellular concentrations of dopamine in the nucleus accumbens (NAcc).

OBJECTIVES

To determine the efficacy and safety of NAcc surgery for the treatment of substance dependence.

MATERIALS AND METHODS

Adhering to PRISMA guidelines, we performed a systematic review to identify all original studies in which NAcc surgery was performed to treat relapsing drug addiction with a minimum follow-up of six months. From database inception to April 10, 2020, we searched PubMed, Scopus, and LILACS. Two reviewers independently selected studies and extracted data. The main outcome was the relapse rate. The GRADE methods were applied to evaluate the quality of evidence. This study was registered with PROSPERO CRD42020177054.

RESULTS

Fifteen studies involving 359 participants met inclusion criteria; eight (56%) included NAcc deep brain stimulation (DBS) in 13 patients with addiction for alcohol (N = 6, 46.1%), opioid (N = 4, 30.7%), and nicotine (N = 3, 15.3%); seven studies (N = 346, 44%) performed NAcc radiofrequency (RF) ablation for opioid (N = 334) and alcohol (N = 12) dependence. Relapse rates were 38.4% for DBS and 39% for RF ablation.

CONCLUSIONS

Despite available studies reporting a benefit in the treatment of drug addictions with NAcc surgery, this systematic review stresses the need for carefully planned prospective studies in order to further address the efficacy and indications.

Factors of Negative Affect in Elderly Patients With Substance Use Disorders During COVID-19 Pandemic

Background: The outbreak of the novel coronavirus disease 2019 (COVID-19) has become the greatest public health emergency and has attracted global attention. During the COVID-19 pandemic, the negative affect (NA) of elderly patients with substance use disorders (SUDs) has also become a more serious public concern. The current study aims to clarify the NA and its influencing factors in elderly patients with SUDs during the pandemic. Methods: Two psychiatrists conducted semi-structured interviews with 77 SUD patients aged above 50 years to collect their demographical information and certain drug use characteristics. Barratt Impulse Scale and the Positive and Negative Affect Scale were used to obtain information about patients' self-reported impulsivity and NA. Results: Univariate linear regression analysis showed that NA was positively correlated with the frequency of drug use, type of SUDs, cravings during COVID-19, and impulsivity. Multiple linear regression analysis showed that being female, higher frequency of drug use, stronger cravings, and greater impulsiveness jointly accounted for the variation of NA in elderly patients with SUDs. Conclusions: This study confirmed that, during the COVID-19 pandemic, gender, frequency of drug use, cravings, and impulsivity were associated with NA in elderly patients with SUDs. This study provided a theoretical basis for clinicians to reduce the patients' NA.

Successful Treatment of Psychiatric Symptoms after Traumatic Brain Injury Using Deep Brain Stimulation to the Anterior Limb of Internal Capsule-Nucleus Accumbens

Psychiatric symptoms are common after traumatic brain injury (TBI), and some patients have poor drug therapeutic efficacy. We report a successfully treated case of psychiatric symptoms after TBI using deep brain stimulation (DBS) to the anterior limb of internal capsule (ALIC)-nucleus accumbens (NAc) in a 76-year-old woman. The patient suffered from auditory hallucination, mood changes, and insomnia caused by TBI. Psychological test assessment showed the scores of Hamilton Anxiety Scale, Hamilton Depression Scale and Positive and Negative Syndrome Scale were 30, 35, and 96 respectively. Head magnetic resonance imaging scan showed right temporal lobe encephalomalacia. Head magnetic resonance spectroscopy (MRS) showed bilateral basal ganglia choline increased relatively. After DBS to the ALIC-NAc, the target parameters were adjusted. The psychiatric symptoms were completely improved and the result of head MRS was normal in the end. The current report declares that DBS is reversible, adjustable and safe in the treatment of psychiatric symptoms caused by TBI. DBS to the ALIC-NAc should be considered as a possible treatment choice once a patient showed psychiatric symptoms after TBI.

The Nucleus Accumbens: A Common Target in the Comorbidity of Depression and Addiction

The comorbidity of depression and addiction has become a serious public health issue, and the relationship between these two disorders and their potential mechanisms has attracted extensive attention. Numerous studies have suggested that depression and addiction share common mechanisms and anatomical pathways. The nucleus accumbens (NAc) has long been considered a key brain region for regulating many behaviors, especially those related to depression and addiction. In this review article, we focus on the association between addiction and depression, highlighting the potential mediating role of the NAc in this comorbidity via the regulation of changes in the neural circuits and molecular signaling. To clarify the mechanisms underlying this association, we summarize evidence from overlapping reward neurocircuitry, the resemblance of cellular and molecular mechanisms, and common treatments. Understanding the interplay between these disorders should help guide clinical comorbidity prevention and the search for a new target for comorbidity treatment.