Contingency management in cocaine abusers: a dose-effect comparison of goods-based versus cash-based incentives

Atomoxetine reduces decisional impulsivity in human cocaine addiction

BACKGROUND

Impulsivity is a well-known determinant of maladaptive behaviour in cocaine use disorder, but there are currently no effective strategies for managing excessive impulsivity. Growing evidence from preclinical and clinical studies suggests that atomoxetine, a selective noradrenaline reuptake inhibitor, is effective in improving impulse control in both health and neuropsychiatric conditions.

METHODS

We investigated the effects of atomoxetine on decisional impulsivity in patients with cocaine use disorder. In a randomised, double-blind, placebo-controlled, crossover study, 28 patients diagnosed with moderate-to-severe cocaine use disorder and 28 matched healthy control participants completed the Cambridge Gamble Task in two separate sessions, where they either received placebo or a single dose of 40 mg atomoxetine on each session. Computational modelling was used to decompose decision-making into three separable components: value, probability, and decisional impulsivity.

RESULTS

Our analyses revealed that patients with cocaine use disorder were impaired in all components of decision-making. Atomoxetine selectively reduced decisional impulsivity in cocaine use disorder patients by reducing their risk-seeking tendencies whilst enhancing their ability to tolerate delays. By contrast, atomoxetine did not affect impulsivity in control participants, but increased their sensitivity to prospective losses.

CONCLUSION

Taken together, our findings support the hypothesis of noradrenergic dysfunction in patients with cocaine use disorder and provide novel translational evidence for the efficacy of atomoxetine in remediating decisional impulsivity in cocaine use disorder.

Reduced brain connectivity underlying value-based choices and outcomes in stimulant use disorder

BACKGROUND

Patients with stimulant use disorder (SUD) show impairments when making value-based choices that are associated with disruptions in neural processing across brain networks. Making optimal choices requires learning from outcomes to update knowledge and further optimise ongoing behaviour. The optimal functioning of neural systems that underpin the ability to make favourable choices is an essential component for life functioning, and successful recovery in patients with SUD. Therefore, we sought to investigate the neural processes that underpin value-based choices in SUD patients. We hypothesise that patients with SUD have reduced functional connectivity while making financial choices during a probabilistic reinforcement learning task.

METHODS

We investigated connectivity associated with loss and reward value-based choices and their outcomes in patients with SUD and healthy control participants during a pharmacological magnetic resonance imaging study. Participants received a single dose of a dopamine receptor agonist, pramipexole, and a dopamine receptor antagonist, amisulpride, in a randomised, double-blind, placebo-controlled, balanced, crossover design. Functional task-related connectivity was analysed taking a whole brain connectomics approach to identify networks that are differentially modulated by dopaminergic receptor functioning.

RESULTS

SUD patients showed widespread reductions in connectivity during both reward and loss value-based choices and outcomes, which were negatively correlated with the duration of stimulant drug use. Disturbances to functional brain connectivity in SUD patients during task performance were not modulated acutely by either amisulpride or pramipexole.

CONCLUSIONS

Reductions in brain connectivity, particularly when making value-based choices and processing outcomes, may underlie learning impairments in SUD patients. Given that acute dopaminergic modulation did not improve brain connectivity impairments in SUD patients, it is likely that alternative treatments are needed.

Contingency management plus acceptance and commitment therapy for initial cocaine abstinence: Results of a sequential multiple assignment randomized trial (SMART)

BACKGROUND

This study tested an adaptive intervention for optimizing abstinence outcomes over phases of treatment for cocaine use disorder using a SMART design. Phase 1 assessed whether 4 weeks of contingency management (CM) improved response with the addition of Acceptance and Commitment Therapy (ACT). Phase 2 assessed pharmacological augmentation with modafinil (MOD) vs. placebo (PLA) for individuals not achieving abstinence during Phase 1.

METHOD

For Phase 1 of treatment, participants (N=118) were randomly allocated to ACT+CM or Drug Counseling (DC+CM), the comparison condition. At week 4, treatment response was defined as the submission of six consecutive cocaine-negative urine drug screens (UDS). Phase 1 non-responders were re-randomized to MOD or PLA as adjunct to their initial treatment. Phase 1 responders continued receiving their initial treatment. Primary outcomes included response rate and proportion of cocaine-negative UDS for Phase 1 and 2. Analyses used Bayesian inference with 80% pre-specified as the posterior probability (PP) threshold constituting moderate evidence that an effect exists.

RESULTS

Phase 1 response was higher in the ACT+CM group (24.5%) compared to the DC+CM group (17.5%; PP = 84.5%). In Phase 2, the proportion of cocaine-negative UDS among Phase 1 responders did not differ by initial treatment (PP = 61.8%) but remained higher overall compared to Phase 1 non-responders (PPs > 99%). No evidence of an effect favoring augmentation with MOD was observed.

DISCUSSION

Adding ACT to CM increased abstinence initiation. Initial responders were more likely to remain abstinent compared to initial non-responders, for whom modafinil was not an effective pharmacotherapy augmentation strategy.

National Institute on Drug Abuse (NIDA) research priorities to support the development of incentive-based treatments for substance use disorders

The purpose of this commentary is to highlight current research priorities of National Institute on Drug Abuse (NIDA) Division of Therapeutics and Medical Consequences (DTMC) regarding the development and testing of incentive-based interventions for the treatment of substance use disorders (SUDs). This manuscript summarizes the NIH Stage Model for behavioral intervention development, briefly reviews existing research on incentive-based treatments for SUDs that falls within the scope of DTMC at NIDA and highlights the development of digital therapeutics-based incentive interventions as an exemplar and high priority area. We briefly review how digital therapeutics approaches may address some common limitations to dissemination of incentive-based interventions and highlight opportunities for integrating incentive-based approaches into pharmacotherapy efficacy trials. Finally, we mention several related funding opportunities for researchers interested in developing incentive-based approaches for SUD treatment. The overall goal of this commentary is to inform the research community of current NIDA priority areas for intervention development and funding.

Implementing an evidence-based prize contingency management protocol for stimulant use

INTRODUCTION

Contingency management (CM) is an efficacious treatment for stimulant use disorders. Support materials for the clinical delivery of prize-based CM are widely accessible, but few resources are available to support design and preparation for CM implementation. This guide aims to fill that gap.

METHOD/RESULTS

The article outlines a suggested prize CM protocol and discusses the best practices most aligned with the evidence base and acceptable-if-necessary modifications. This guide also highlights modifications that are not evidence-based and not recommended. In addition, I discuss practical and clinical aspects of preparing for CM implementation.

CONCLUSIONS

Deviations from evidence-based practices are common, and poorly designed CM is unlikely to impact patient outcomes. This article provides planning stage guidance to support programs' adoption of evidence-based prize CM for the treatment of stimulant use disorders.

Research Compensation and Enhanced Contacts in Studies With Persons Who Use Drugs: Lessons From the COVID-19 Pandemic Demand a Reset

Policy changes resulting from the coronavirus 2019 (COVID-19) pandemic have had a substantial and positive impact on the clinical care of persons with opioid use disorder. These innovative paradigm shifts created a ripe environment for re-evaluating traditional approaches to recruiting and retaining persons who use drugs into research studies. For example, changes to methadone prescribing requirements and authorization of buprenorphine prescriptions via telehealth have both increased access to medications. In this commentary, we contribute to ongoing conversations about the ethics of compensation for participants in addiction-related clinical research and share methods of payment that proved successful in research performed during the pandemic. We also discuss approaches to enrollment and follow-up that were implemented during the height of COVID restrictions. These approaches may mutually benefit both participants and researchers in a post-pandemic era.

High-risk Coronary Plaque Regression in Cash-based Contingency Management Intervention Among Cocaine Users With HIV-associated Subclinical Coronary Atherosclerosis

BACKGROUND

Cocaine use exacerbates human immunodeficiency virus (HIV)-associated subclinical coronary atherosclerosis. We investigated whether cocaine abstinence or reduced use achieved with contingency management (CM) intervention would retard high-risk coronary plaque progression among cocaine users with HIV and subclinical coronary atherosclerosis.

METHODS

Between March 2014 and August 2017, 76 cocaine users with HIV and coronary plaques were enrolled in a study designed to decrease cocaine use and determine whether doing so impacted progression of subclinical coronary atherosclerosis as measured by coronary artery computed tomography examinations. Of the 76, 7 did not complete the study, resulting in 69 participants. A 12-month cash-based CM intervention was implemented to promote cocaine abstinence or reduced cocaine use. Generalized estimating equation approach was used to perform longitudinal data analyses.

FINDINGS

During the 12-month CM, all 69 participants reduced cocaine use, and of these, 25 (36%; 95% confidence interval, 25%-49%) achieved cocaine abstinence. After adjusting for potential confounding factors, generalized estimating equation analyses showed that (1) endothelin-1 (ET-1) levels, a proinflammatory biomarker for endothelial dysfunction, at the 6-month and 12-month visits were significantly lower compared with baseline ET-1 ( P = 0.001 and P < 0.001, respectively), and (2) low-attenuation noncalcified coronary plaque volume, a predictor for myocardial infarction, at 12-month visit was significantly lower compared with baseline low-attenuation noncalcified coronary plaque volume ( P < 0.05).

CONCLUSIONS

The findings of this study have not only demonstrated that CM is effective in achieving a sustained reduction in cocaine use, but also provided compelling evidence that reduction in cocaine use leads to quantifiable cardiovascular health benefits, including concurrent decrease in high-risk plaque burden and ET-1, among cocaine users with HIV-associated coronary atherosclerosis.

Impaired Learning From Negative Feedback in Stimulant Use Disorder: Dopaminergic Modulation

BACKGROUND

Drug-induced alterations to the dopamine system in stimulant use disorder (SUD) are hypothesized to impair reinforcement learning (RL). Computational modeling enables the investigation of the latent processes of RL in SUD patients, which could elucidate the nature of their impairments.

METHODS

We investigated RL in 44 SUD patients and 41 healthy control participants using a probabilistic RL task that assesses learning from reward and punishment separately. In an independent sample, we determined the modulatory role of dopamine in RL following a single dose of the dopamine D2/3 receptor antagonist amisulpride (400 mg) and the agonist pramipexole (0.5 mg) in a randomised, double-blind, placebo-controlled, crossover design. We analyzed task performance using computational modelling and hypothesized that RL impairments in SUD patients would be differentially modulated by a dopamine D2/3 receptor antagonist and agonist.

RESULTS

Computational analyses in both samples revealed significantly reduced learning rates from punishment in SUD patients compared with healthy controls, whilst their reward learning rates were not measurably impaired. In addition, the dopaminergic receptor agents modulated RL parameters differentially in both groups. Both amisulpride and pramipexole impaired RL parameters in healthy participants, but ameliorated learning from punishment in SUD patients.

CONCLUSION

Our findings suggest that RL impairments seen in SUD patients are associated with altered dopamine function.

Effect of Financial Incentives for Process, Outcomes, or Both on Cholesterol Level Change: A Randomized Clinical Trial

Importance

Financial incentives may improve health behaviors. It is unknown whether incentives are more effective if they target a key process (eg, medication adherence), an outcome (eg, low-density lipoprotein cholesterol [LDL-C] levels), or both.

Objective

To determine whether financial incentives awarded daily for process (adherence to statins), awarded quarterly for outcomes (personalized LDL-C level targets), or awarded for process plus outcomes induce reductions in LDL-C levels compared with control.

Design, Setting, and Participants

A randomized clinical trial was conducted from February 12, 2015, to October 3, 2018; data analysis was performed from October 4, 2018, to May 27, 2021, at the University of Pennsylvania Health System, Philadelphia. Participants included 764 adults with an active statin prescription, elevated risk of atherosclerotic cardiovascular disease, suboptimal LDL-C level, and evidence of imperfect adherence to statin medication.

Interventions

Interventions lasted 12 months. All participants received a smart pill bottle to measure adherence and underwent LDL-C measurement every 3 months. In the process group, daily financial incentives were awarded for statin adherence. In the outcomes group, participants received incentives for achieving or sustaining at least a quarterly 10-mg/dL LDL-C level reduction. The process plus outcomes group participants were eligible for incentives split between statin adherence and quarterly LDL-C level targets.

Main Outcomes and Measures

Change in LDL-C level from baseline to 12 months, determined using intention-to-treat analysis.

Results

Of the 764 participants, 390 were women (51.2%); mean (SD) age was 62.4 (10.0) years, 310 (40.6%) had diabetes, 298 (39.0%) had hypertension, and mean (SD) baseline LDL-C level was 138.8 (37.6) mg/dL. Mean LDL-C level reductions from baseline to 12 months were -36.9 mg/dL (95% CI, -42.0 to -31.9 mg/dL) among control participants, -40.0 mg/dL (95% CI, -44.7 to -35.4 mg/dL) among process participants, -41.6 mg/dL (95% CI, -46.3 to -37.0 mg/dL) among outcomes participants, and -42.8 mg/dL (95% CI, -47.4 to -38.1 mg/dL) among process plus outcomes participants. In exploratory analysis among participants with diabetes and hypertension, no spillover effects of incentives were detected compared with the control group on hemoglobin A1c level and blood pressure over 12 months.

Conclusions and Relevance

In this randomized clinical trial, process-, outcomes-, or process plus outcomes-based financial incentives did not improve LDL-C levels vs control.

Trial Registration

ClinicalTrials.gov Identifier: NCT02246959.

Prevention of Urinary Stones With Hydration (PUSH): Design and Rationale of a Clinical Trial

RATIONALE & OBJECTIVE

Although maintaining high fluid intake is an effective low-risk intervention for the secondary prevention of urinary stone disease, many patients with stones do not increase their fluid intake.

STUDY DESIGN

We describe the rationale and design of the Prevention of Urinary Stones With Hydration (PUSH) Study, a randomized trial of a multicomponent behavioral intervention program to increase and maintain high fluid intake. Participants are randomly assigned (1:1 ratio) to the intervention or control arm. The target sample size is 1,642 participants.

SETTING & PARTICIPANTS

Adults and adolescents 12 years and older with a symptomatic stone history and low urine volume are eligible. Exclusion criteria include infectious or monogenic causes of urinary stone disease and comorbid conditions precluding increased fluid intake.

INTERVENTIONS

All participants receive usual care and a smart water bottle with smartphone application. Participants in the intervention arm receive a fluid intake prescription and an adaptive program of behavioral interventions, including financial incentives, structured problem solving, and other automated adherence interventions. Control arm participants receive guideline-based fluid instructions.

OUTCOMES

The primary end point is recurrence of a symptomatic stone during 24 months of follow-up. Secondary end points include changes in radiographic stone burden, 24-hour urine output, and urinary symptoms.

LIMITATIONS

Periodic 24-hour urine volumes may not fully reflect daily behavior.

CONCLUSIONS

With its highly novel features, the PUSH Study will address an important health care problem.

FUNDING

National Institute of Diabetes and Digestive and Kidney Diseases.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCT03244189.

Misalignment of Stakeholder Incentives in the Opioid Crisis

The current opioid epidemic has killed more than 446,000 Americans over the past two decades. Despite the magnitude of the crisis, little is known to what degree the misalignment of incentives among stakeholders due to competing interests has contributed to the current situation. In this study, we explore evidence in the literature for the working hypothesis that misalignment rooted in the cost, quality, or access to care can be a significant contributor to the opioid epidemic. The review identified several problems that can contribute to incentive misalignment by compromising the triple aims (cost, quality, and access) in this epidemic. Some of these issues include the inefficacy of conventional payment mechanisms in providing incentives for providers, practice guidelines in pain management that are not easily implementable across different medical specialties, barriers in adopting multi-modal pain management strategies, low capacity of providers/treatments to address opioid/substance use disorders, the complexity of addressing the co-occurrence of chronic pain and opioid use disorders, and patients' non-adherence to opioid substitution treatments. In discussing these issues, we also shed light on factors that can facilitate the alignment of incentives among stakeholders to effectively address the current crisis.

A sequential multiple assignment randomized trial for cocaine cessation and relapse prevention: Tailoring treatment to the individual

Drug addiction is a chronic, devastating, but treatable disorder. A core principle of drug addiction treatment states that no single treatment is appropriate for everyone (NIDA, 2012); treatments need to adjust based on patient characteristics and response in order to be maximally effective. For cocaine use disorders (CUD), specifically, the most potent intervention currently available for initiating abstinence is behavior therapy using contingency management (CM) procedures, with early cessation being a robust predictor of future abstinence. This raises two key questions for treatment development research: First, can we significantly improve initial CM response rates with targeted adjunctive interventions? Second, for individuals who fail to achieve initial abstinence with CM, is pharmacotherapy an effective augmentation strategy? This paper describes how a sequential, multiple assignment, randomized trial (SMART) design has advantages over a fixed-intervention approach when it comes to collecting data needed to answer both questions. The first aim will examine whether Acceptance and Commitment Therapy (ACT) in combination with CM increases initial abstinence response rates (i.e., 2 consecutive weeks of cocaine-negative urine screens). The second aim will examine whether ACT+CM in combination with modafinil promotes abstinence achievement in initial non-responders. Results are expected to inform how we tailor treatment of CUD to maximize outcomes.

Contingency Management interventions for non-prescribed drug use during treatment for opiate addiction: A systematic review and meta-analysis

BACKGROUND AND AIMS

Use of non-prescribed drugs during treatment for opiate addiction reduces treatment success, creating a need for effective interventions. This review aimed to assess the efficacy of contingency management, a behavioural treatment that uses rewards to encourage desired behaviours, for treating non-prescribed drug use during opiate addiction treatment.

METHODS

A systematic search of the databases Embase, PsychInfo, PsychArticles and Medline from inception to March 2015 was performed. Random effects meta-analysis tested the use of contingency management to treat the use of drugs during opiate addiction treatment, using either longest duration of abstinence (LDA) or percentage of negative samples (PNS). Random effects moderator analyses were performed for six potential moderators: drug targeted for intervention, decade in which the study was carried out, study quality, intervention duration, type of reinforcer, and form of opiate treatment.

RESULTS

The search returned 3860 papers; 22 studies met inclusion criteria and were meta-analysed. Follow-up data was only available for three studies, so all analyses used end of treatment data. Contingency management performed significantly better than control in reducing drug use measured using LDA (d=0.57, 95% CI: 0.42-0.72) or PNS (d=0.41) (95% CI: 0.28-0.54). This was true for all drugs other than opiates. The only significant moderator was drug targeted (LDA: Q=10.75, p=0.03).

CONCLUSION

Contingency management appears to be efficacious for treating most drug use during treatment for opiate addiction. Further research is required to ascertain the full effects of moderating variables, and longer term effects.

Contingency management for tobacco smoking during opioid addiction treatment: a randomised pilot study

INTRODUCTION

Smoking rates among individuals in treatment for opioid addiction are close to five times that of the general public. Moreover, drug-addicted smokers have a premature mortality rate four times greater than drug-addicted non-smokers. The aim of this pilot study was to investigate whether contingency management (CM) can be successfully added to evidence-based stop smoking treatment in individuals undergoing treatment for opioid addiction and assess preliminary evidence for its impact.

PARTICIPANTS

Forty tobacco smokers currently undergoing treatment for opioid addiction.

INTERVENTION

Escalating with reset CM as an adjunct to standard smoking cessation treatment. Financial incentives will be administered over a 5-week period for either biochemically verified abstinence from smoking or attendance at the clinic. Participants will be randomised to conditions stratified on current levels of smoking (high or low).

OBJECTIVES AND ANALYSES

To assess whether a CM intervention can be successfully added to standard stop smoking services treatment, in patients undergoing outpatient treatment for opioid addiction. This will be measured as the number of people completing the 5 weeks of the intervention.

ETHICS AND DISSEMINATION

Ethics approval for the study was granted on the 16 June 2016 by the London-city and east (reference 16/LO/0990) ethics committee. The pilot study was retrospectively registered on clincaltrials.gov in January 2017 (ID: NCT03015597). A SPIRIT checklist and figure are available for this protocol. It is planned that the results of this study will be published in an academic journal.

Contingency Management Interventions for HIV, Tuberculosis, and Hepatitis Control Among Individuals With Substance Use Disorders: A Systematized Review

Hepatitis, HIV and tuberculosis are significant and costly public health problems that disproportionately affect individuals with substance use disorders (SUDs). Incentive-based treatment approaches (i.e., contingency management; CM) are highly effective at reducing drug use. The primary aim of this report is to review the extant literature that examines the efficacy of CM interventions for the prevention, diagnosis and treatment of hepatitis, HIV and tuberculosis among individuals with SUDs. A literature search identified 23 controlled studies on this topic. In approximately 85% of the studies, CM produced significantly better adherence to prevention, diagnosis and treatment-related medical services, with adherence rates averaging almost 35% higher among patients receiving incentives vs. control condition participants. Findings from these studies parallel the results of a meta-analysis of CM interventions for the treatment of SUDs. The results also suggest that the principles that underlie the efficacy of CM generalize across infectious disease and substance abuse treatment behaviors. The application of additional principles from the literature on CM for treatment of SUDs to interventions targeting infectious disease control would be beneficial. Further development and dissemination of these interventions has the potential to greatly impact public health.

Rationale and design of a randomized trial of automated hovering for post-myocardial infarction patients: The HeartStrong program

BACKGROUND

Coronary artery disease is the single leading cause of death in the United States, and medications can significantly reduce the rate of repeat cardiovascular events and treatment procedures. Adherence to these medications, however, is very low.

METHODS

HeartStrong is a national randomized trial offering 3 innovations. First, the intervention is built on concepts from behavioral economics that we expect to enhance its effectiveness. Second, the implementation of the trial takes advantage of new technology, including wireless pill bottles and remote feedback, to substantially automate procedures. Third, the trial's design includes an enhancement of the standard randomized clinical trial that allows rapid-cycle innovation and ongoing program enhancement.

RESULTS

Using a system involving direct data feeds from 6 insurance partners followed by mail, telephone, and email contact, we enrolled 1,509 patients discharged from the hospital with acute myocardial infarction in a 2:1 ratio of intervention:usual care. The intervention period lasts 1 year; the primary outcome is time to first fatal or nonfatal acute vascular event or revascularization, including acute myocardial infarction, unstable angina, stroke, acute coronary syndrome admission, or death.

CONCLUSIONS

Our randomized controlled trial of the HeartStrong program will provide an evaluation of a state-of-the-art behavioral economic intervention with a number of important pragmatic features. These include a tailored intervention responding to patient activity, streamlining of consent and implementation processes using new technologies, outcomes centrally important to patients, and the ability to implement rapid-cycle innovation.

Development of a translational model to screen medications for cocaine use disorder II: Choice between intravenous cocaine and money in humans

BACKGROUND

A medication for treating cocaine use disorder has yet to be approved. Laboratory-based evaluation of candidate medications in animals and humans is a valuable means to demonstrate safety, tolerability and initial efficacy of potential medications. However, animal-to-human translation has been hampered by a lack of coordination. Therefore, we designed homologous cocaine self-administration studies in rhesus monkeys (see companion article) and human subjects in an attempt to develop linked, functionally equivalent procedures for research on candidate medications for cocaine use disorder.

METHODS

Eight (N=8) subjects with cocaine use disorder completed 12 experimental sessions in which they responded to receive money ($0.01, $1.00 and $3.00) or intravenous cocaine (0, 3, 10 and 30mg/70kg) under independent, concurrent progressive-ratio schedules. Prior to the completion of 9 choice trials, subjects sampled the cocaine dose available during that session and were informed of the monetary alternative value.

RESULTS

The allocation of behavior varied systematically as a function of cocaine dose and money value. Moreover, a similar pattern of cocaine choice was demonstrated in rhesus monkeys and humans across different cocaine doses and magnitudes of the species-specific alternative reinforcers. The subjective and cardiovascular responses to IV cocaine were an orderly function of dose, although heart rate and blood pressure remained within safe limits.

CONCLUSIONS

These coordinated studies successfully established drug versus non-drug choice procedures in humans and rhesus monkeys that yielded similar cocaine choice behavior across species. This translational research platform will be used in future research to enhance the efficiency of developing interventions to reduce cocaine use.

Cocaine choice procedures in animals, humans, and treatment-seekers: Can we bridge the divide?

Individuals with cocaine use disorder chronically self-administer cocaine to the detriment of other rewarding activities, a phenomenon best modeled in laboratory drug-choice procedures. These procedures can evaluate the reinforcing effects of drugs versus comparably valuable alternatives under multiple behavioral arrangements and schedules of reinforcement. However, assessing drug-choice in treatment-seeking or abstaining humans poses unique challenges: for ethical reasons, these populations typically cannot receive active drugs during research studies. Researchers have thus needed to rely on alternative approaches that approximate drug-choice behavior or assess more general forms of decision-making, but whether these alternatives have relevance to real-world drug-taking that can inform clinical trials is not well-understood. In this mini-review, we (A) summarize several important modulatory variables that influence cocaine choice in nonhuman animals and non-treatment seeking humans; (B) discuss some of the ethical considerations that could arise if treatment-seekers are enrolled in drug-choice studies; (C) consider the efficacy of alternative procedures, including non-drug-related decision-making and 'simulated' drug-choice (a choice is made, but no drug is administered) to approximate drug choice; and (D) suggest opportunities for new translational work to bridge the current divide between preclinical and clinical research.

Effectiveness of secondary prevention and treatment interventions for crack-cocaine abuse: a comprehensive narrative overview of English-language studies

There are an estimated several million crack-cocaine users globally; use is highest in the Americas. Most crack users are socio-economically marginalized (e.g., homeless), and feature elevated risks for morbidity (e.g., blood-borne viruses), mortality and crime/violence involvement, resulting in extensive burdens. No comprehensive reviews of evidence-based prevention and/or treatment interventions specifically for crack use exist. We conducted a comprehensive narrative overview of English-language studies on the efficacy of secondary prevention and treatment interventions for crack (cocaine) abuse/dependence. Literature searches (1990-2014) using pertinent keywords were conducted in main scientific databases. Titles/abstracts were reviewed for relevance, and full studies were included in the review if involving a primary prevention/treatment intervention study comprising a substantive crack user sample. Intervention outcomes considered included drug use, health risks/status (e.g., HIV or sexual risks) and select social outcome indicators. Targeted (e.g., behavioral/community-based) prevention measures show mixed and short-term effects on crack use/HIV risk outcomes. Material (e.g., safer crack use kit distribution) interventions also document modest efficacy in risk reduction; empirical assessments of environmental (e.g., drug consumption facilities) for crack smokers are not available. Diverse psycho-social treatment (including contingency management) interventions for crack abuse/dependence show some positive but also limited/short-term efficacy, yet likely constitute best currently available treatment options. Ancillary treatments show little effects but are understudied. Despite ample studies, pharmaco-therapeutic/immunotherapy treatment agents have not produced convincing evidence; select agents may hold potential combined with personalized approaches and/or psycho-social strategies. No comprehensively effective 'gold-standard' prevention/treatment interventions for crack abuse exist; concerted research towards improved interventions is urgently needed.

Standard magnitude prize reinforcers can be as efficacious as larger magnitude reinforcers in cocaine-dependent methadone patients

OBJECTIVE

Contingency management (CM) reduces cocaine use in methadone patients, but only about 50% of patients respond to CM interventions. This study evaluated whether increasing magnitudes of reinforcement will improve outcomes.

METHOD

Cocaine-dependent methadone patients (N = 240) were randomized to 1 of 4 12-week treatment conditions: usual care (UC); UC plus standard prize CM, in which average expected prize earnings were about $300; UC plus high magnitude prize CM, in which average expected prize earnings were about $900; or UC plus voucher CM, with an expected maximum of about $900 in vouchers.

RESULTS

All 3 CM conditions yielded significant reductions in cocaine use relative to UC, with effect sizes (d) ranging from 0.38 to 0.59. No differences were noted between CM conditions, with at least 55% of patients in each CM condition achieving 1 week or more of cocaine abstinence versus 35% in UC. During the 12 weeks after the intervention ended, CM increased time until relapse relative to UC, but the effects of CM were no longer significant at a 12-month follow-up.

CONCLUSIONS

Providing the standard magnitude of $300 in prizes was as effective as larger magnitude CM in cocaine-dependent methadone patients in this study. Given its strong evidence base and relatively low costs, standard magnitude prize CM should be considered for adoption in methadone clinics to encourage cocaine abstinence, but new methods need to be developed to sustain abstinence.

Achieving cannabis cessation -- evaluating N-acetylcysteine treatment (ACCENT): design and implementation of a multi-site, randomized controlled study in the National Institute on Drug Abuse Clinical Trials Network

Despite recent advances in behavioral interventions for cannabis use disorders, effect sizes remain modest, and few individuals achieve long-term abstinence. One strategy to enhance outcomes is the addition of pharmacotherapy to complement behavioral treatment, but to date no efficacious medications targeting cannabis use disorders in adults through large, randomized controlled trials have been identified. The National Institute on Drug Abuse Clinical Trials Network (NIDA CTN) is currently conducting a study to test the efficacy of N-acetylcysteine (NAC) versus placebo (PBO), added to contingency management, for cannabis cessation in adults (ages 18-50). This study was designed to replicate positive findings from a study in cannabis-dependent adolescents that found greater odds of abstinence with NAC compared to PBO. This paper describes the design and implementation of an ongoing 12-week, intent-to-treat, double-blind, randomized, placebo-controlled study with one follow-up visit four weeks post-treatment. Approximately 300 treatment-seeking cannabis-dependent adults will be randomized to NAC or PBO across six study sites in the United States. The primary objective of this 12-week study is to evaluate the efficacy of twice-daily orally-administered NAC (1200 mg) versus matched PBO, added to contingency management, on cannabis abstinence. NAC is among the first medications to demonstrate increased odds of abstinence in a randomized controlled study among cannabis users in any age group. The current study will assess the cannabis cessation efficacy of NAC combined with a behavioral intervention in adults, providing a novel and timely contribution to the evidence base for the treatment of cannabis use disorders.

The ABCs of incentive-based treatment in health care: a behavior analytic framework to inform research and practice

Behavior plays an important role in health promotion. Exercise, smoking cessation, medication adherence, and other healthy behavior can help prevent, or even treat, some diseases. Consequently, interventions that promote healthy behavior have become increasingly common in health care settings. Many of these interventions award incentives contingent upon preventive health-related behavior. Incentive-based interventions vary considerably along several dimensions, including who is targeted in the intervention, which behavior is targeted, and what type of incentive is used. More research on the quantitative and qualitative features of many of these variables is still needed to inform treatment. However, extensive literature on basic and applied behavior analytic research is currently available to help guide the study and practice of incentive-based treatment in health care. In this integrated review, we discuss how behavior analytic research and theory can help treatment providers design and implement incentive-based interventions that promote healthy behavior.

Under what conditions is it ethical to offer incentives to encourage drug-using women to use long-acting forms of contraception?

AIMS

To stimulate debate by examining ethical issues raised by Project Prevention, a US-based organization that offers $US300 to addicted individuals who agree to either undergo surgical sterilization or use long-acting forms of contraception.

METHOD

An analysis of key ethical questions raised by Project Prevention.

RESULTS

The important issues for debate are: (i) what are the reproductive rights of drug-using women; (ii) does a substantial cash incentive undermine the ability of addicted women to make free and informed decisions about long-term contraception; and (iii) how can we best assist addicted women to access good reproductive health care and obtain treatment for their addiction?

CONCLUSIONS

We need more research on ways in which small non-cash incentives for reversible methods of contraception could be used in a morally acceptable and effective way to promote the sexual, reproductive and general health of addicted women.

Monetary-based consequences for drug abstinence: methods of implementation and some considerations about the allocation of finances in substance abusers

Conceptualizing drug abuse within the framework of behavioral theories of choice highlights the relevance of environmental variables in shifting behavior away from drug-related purchases. Choosing to use drugs results in immediate and certain consequences (e.g., drug high and relief from withdrawal), whereas choosing abstinence typically results in delayed, and often uncertain, consequences (e.g., improved health, interpersonal relationships, money).

METHODS

This is a selective review of the literature on Contingency management (CM).

RESULTS

We highlight a variety of methods to deliver CM in practical, effective, and sustainable ways. We consider a number of parameters that are critical to the success of monetary-based CM, and the role of the context in influencing CM's effects. To illustrate the broad range of applications of CM, we also review different methods for arranging contingencies to promote abstinence and other relevant behavior. Finally, we discuss some considerations about how drug-dependent individuals allocate their finances in the context of CM interventions.

CONCLUSIONS

Contingency management (CM) increases choice for drug abstinence via the availability of immediate, financial-based gains, contingent on objective evidence of abstinence.

Paying substance abusers in research studies: where does the money go?

BACKGROUND

Research involving substance-abusing participants is often hindered by low rates of recruitment and retention. Research suggests that monetary payment or remuneration can be an effective strategy to overcome these obstacles.

OBJECTIVES

This article provides a brief overview of these issues and provides data reflecting how substance-abusing participants in several of our studies used their baseline and follow-up payments. We also present research findings related to how the mode of payment (i.e., cash, check, gift card) may affect how payments are used.

CONCLUSIONS AND SIGNIFICANCE

Overall, our findings suggest that participants use their research payments in a responsible and safe manner. Limitations and recommendations for future research are discussed.

Pay-for-performance in a community substance abuse clinic

Pay-for-performance (P4P) strategies improve employee productivity and morale in business settings and are increasingly being implemented in medical care settings. This study investigated whether P4P could improve treatment utilization and retention at a community drug treatment clinic. Counselors had the opportunity to earn cash bonuses based on therapy attendance rates of individual clients and on the quarterly retention rates of their caseload. Using a pre-post study design, average therapy sessions attended during the first month of treatment increased from 4.6 sessions prior to the intervention to 5.5 sessions per client during the intervention. The 90-day client retention rate increased from 40% to 53%. Additional analyses suggest that the improvement in the 90-day retention was mediated by the increase in attendance during the first month of treatment. This project demonstrates that implementing a P4P incentive program in community drug abuse treatment clinics is feasible and effective at improving utilization and retention.

Monetary alternative reinforcers more effectively decrease intranasal cocaine choice than food alternative reinforcers

Cocaine dependence continues to be a significant public health concern. Contingency management, wherein alternative reinforcers are made available upon cocaine abstinence, has shown promise for decreasing cocaine use. Other research has modeled this effect and demonstrated that alternative reinforcers also reduce cocaine self-administration in the laboratory. Results from both clinical and laboratory studies suggest that the type and value of alternative reinforcers influences their ability to decrease drug choice. The purpose of the present experiment was to determine the effect of money or food alternative reinforcers, valued at $0.01, 0.25, 0.50 and 1.00, on intranasal cocaine (4 [placebo] and 30 mg) choice. Cocaine was chosen to a greater extent than placebo across alternative reinforcer types and values, but the monetary alternative reinforcer suppressed drug choice to a greater degree than the food reinforcer. These results are concordant with previous findings and suggest that money may be a more effective alternative reinforcer for decreasing cocaine use. Future research should determine the sensitivity of this model to specific behavioral aspects of contingency management and whether food could compete with drugs as reinforcers in humans under laboratory conditions.

Human drug addiction is more than faulty decision-making

We commend Redish et al. for the progress they have made in bringing a measure of theoretical order to the processes that underlie drug addiction. However, incorporating information about situations in which drug users do not exhibit faulty decision-making into the theory would greatly enhance its generality and practical value. This commentary draws attention to the relevant human substance abuse literature.