A Systematic Review of Noninvasive Brain Stimulation for Opioid Use Disorder

BACKGROUND

There is a great public health need to identify novel treatment strategies for opioid use disorder (OUD) in order to reduce relapse and overdose. Noninvasive brain stimulation (NIBS) has demonstrated preliminary effectiveness for substance use, but little is known about its use in OUD. Neuromodulation may represent a potential adjunctive treatment modality for OUD, so we conducted a systematic review to understand the state of the current research in this field.

METHODS

We conducted a systematic review of studies using noninvasive brain stimulation to affect clinical outcomes related to substance use for adults with opioid use disorder. We searched the following online databases: PubMed, The Cochrane Library, PsycINFO (EBSCOhost, 1872-present), and Science Citation Index Expanded (ISI Web of Science, 1945-present). All studies that measured clinical outcomes related to substance use, including cue-induced craving, were included. We assessed risk of bias using the Cochrane Handbook.

RESULTS

The initial search yielded 5590 studies after duplicates were removed. After screening titles and abstracts, 14 full-text studies were assessed for eligibility. Five studies were determined to meet inclusion criteria with a combined total subjects of N = 150. Given the paucity of studies and small number of total subjects, no quantitative analysis was performed. These studies used TMS (n = 3), tDCS (n = 1), and the BRIDGE device (n = 1), a noninvasive percutaneous electrical nerve field stimulator, to reduce cue-induced craving (n = 3), reduce clinical withdrawal symptoms (n = 1), or measure substance-use-related cortical plasticity (n = 1).

CONCLUSIONS

There is a dearth of research in the area of noninvasive brain stimulation for OUD. NIBS represents a novel treatment modality that should be further investigated for OUD.

Effectiveness of the behavior change intervention to improve harm reduction self-efficacy among people who inject drugs in Thailand

BACKGROUND

People who inject drugs (PWID) in Thailand reported unsafe injection practices resulting in injection-related health consequences. Harm reduction self-efficacy plays an important role and could be improved to reduce harm associated with injecting drugs. Evidence-based interventions targeting PWID are needed. This study sought to evaluate the effectiveness of the behavior change intervention within the PWID population.

METHODS

The behavior change intervention, Triple-S, was designed to improve harm reduction self-efficacy among PWID. This quasi-experimental study was a pre- and post-comparison with a control group design. Participants were PWID, aged 18-45 years, and located in Bangkok. Changes in harm reduction self-efficacy of the intervention group were compared with the control group using paired and independent t-test.

RESULTS

Most of PWID were male (84%), had a secondary school and lower education (71%), were single, and had a mean age of 41 years. They had been injecting drugs for an average of 20 years, and the median of drug injections per week was ten times in the past month. Pre- and post-intervention effects were measured and results showed that the intervention group reported improvement in harm reduction self-efficacy in negative emotional conditions (P=0.048).

CONCLUSION

Our findings suggest that Triple-S intervention can significantly improve harm reduction self-efficacy in negative emotional conditions. The results may suggest the importance of behavior change intervention, especially when integrated with services provided by drop-in centers. The intervention can be further developed to cover other harm reduction behaviors and improve harm reduction self-efficacy.

Enhancing motivation within a rapid opioid substitution treatment feasibility RCT: a nested qualitative study

Background

Opioid substitution treatment (OST) has multiple benefits for heroin injectors and is an evidence-based major component of international treatment. The current qualitative study sought to explore participants’ attitudes to and reasons for participating in a feasibility randomised trial in primary care offering ‘same day’ OST (methadone) for injecting heroin users compared to usual care.

Methods

Twenty injecting heroin users (8 intervention and 12 controls; 16 males and 4 females) were interviewed; purposive sampling was used to select a maximum variation sample from those who agreed; and analysis used thematic methods.

Results

Motivation to join the trial included the need to secure treatment set against some ambivalence due to previous negative experiences of trying to obtain OST. Positive effects of securing methadone via the trial, included self-reported improvements in health and self-care; reduction in crime, stress and drug use. Completing the baseline questionnaires at recruitment appeared to enhance motivation for treatment for all participants. For some control participants, this motivation seemed to increase a sense of self-efficacy and cognitive dissonance generated was resolved by seeking treatment from their GP. Self-determination theory suggests that behaviour change may have been initiated during the recruitment appointment, resulting in an increased determination to seek treatment amongst control participants.

Conclusions

Taking part in the ‘script in a day’ trial enabled participants in the intervention arm to gain same-day access to methadone and reduce their drug use. For those in the control arm, completing the baseline questionnaires at recruitment appeared to create cognitive dissonance between their current health state and own aspirations, so increasing motivation for treatment. Over 50% obtained and were still in receipt of OST (methadone or buprenorphine) at the 3 month follow-up. We suggest that a regular ‘health evaluation’ for injecting heroin users not in treatment, paired with low-barrier access to treatment, may be a way of exploring this and encouraging more into obtaining OST more quickly and at the best time for them. This intervention should be delivered without pressure for change.

Clinical trial registration

This trial is registered with International Standard Randomised Controlled Trial Number Register: SCript In a Day for injecting drug users: feasibility trial: ISRCTN16846554.

Can needle and syringe programmes and opiate substitution therapy achieve substantial reductions in hepatitis C virus prevalence? Model projections for different epidemic settings

AIMS

To investigate the impact of scaling-up opiate substitution therapy (OST) and high coverage needle and syringe programmes (100%NSP-obtaining more sterile syringes than you inject) on HCV prevalence among injecting drug users (IDUs).

DESIGN

Hepatitis C virus HCV transmission modelling using U.K. estimates for effect of OST and 100%NSP on individual risk of HCV infection.

SETTING

Range of chronic HCV prevalent (20/40/60%) settings with no OST/100%NSP, and U.K. setting with 50% coverage of both OST and 100%NSP.

PARTICIPANTS

Injecting drug users.

MEASUREMENTS

Decrease in HCV prevalence after 5-20 years due to scale-up of OST and 100%NSP to 20/40/60% coverage in no OST/100%NSP settings, or from 50% to 60/70/80% coverage in the U.K. setting.

FINDINGS

For 40% chronic HCV prevalence, scaling-up OST and 100%NSP from 0% to 20% coverage reduces HCV prevalence by 13% after 10 years. This increases to a 24/33% relative reduction at 40/60% coverage. Marginally less impact occurs in higher prevalence settings over 10 years, but this becomes more pronounced over time. In the United Kingdom, without current coverage levels of OST and 100%NSP the chronic HCV prevalence could be 65% instead of 40%. However, increasing OST and 100%NSP coverage further is unlikely to reduce chronic prevalence to less than 30% over 10 years unless coverage becomes ≥80%.

CONCLUSIONS

Scaling-up opiate substitution therapy and high coverage needle and syringe programmes can reduce hepatitis C prevalence among injecting drug users, but reductions can be modest and require long-term sustained intervention coverage. In high coverage settings, other interventions are needed to further decrease hepatitis C prevalence. In low coverage settings, sustained scale-up of both interventions is needed.