Psychological treatments for stimulant misuse, comparing and contrasting those for amphetamine dependence and those for cocaine dependence

A randomized clinical trial of disulfiram at higher doses for the treatment of cocaine use disorder among methadone-stabilized patients

PURPOSE/BACKGROUND

Previously, disulfiram less than 250 mg/day increased cocaine use relative to placebo whereas disulfiram at 250 mg/day did not differ from placebo among methadone-stabilized individuals with dual cocaine and opioid dependence, suggesting disulfiram at higher doses needed to be tested. This study determined tolerability and efficacy of disulfiram at higher doses (250-500 mg/day).

METHODS/PROCEDURES

In a 14-wk, double blind, placebo-controlled clinical trial, 53 participants with cocaine and opioid dependence were enrolled, inducted onto methadone (weeks 1-2), randomized to receive placebo or disulfiram (250, 375 or 500 mg/day) during weeks 3-14, and provided weekly 1-h individual cognitive behavior therapy throughout. Thrice-weekly urine samples were tested for the presence of cocaine metabolite. Weekly vital signs and monthly mood assessments were obtained.

RESULTS/FINDINGS

Disulfiram groups generally did not differ on subject characteristics or retention. Cocaine-positive urine samples showed a significant increase over time in the placebo group (p = 0.04), with the placebo slope being significantly greater than horizontal. Cocaine-positive urine samples decreased over time in the disulfiram 250 mg (p = 0.014) and 375 mg (p = 0.015), but not 500 mg (p = 0.11), groups relative to placebo, although slopes of these medication groups did not differ significantly from horizontal (p > 0.15). No clinically significant differences across groups with respect to vital signs or mood ratings occurred.

IMPLICATIONS/CONCLUSIONS

Although preliminary due to the small sample size, disulfiram at 250-375 mg/day may be ineffective in reducing cocaine use and have limited efficacy to prevent increases in cocaine use among methadone-stabilized patients with dual cocaine and opioid dependence.

Trends in cocaine and crystal methamphetamine injection over time in a Canadian setting between 2008 and 2018

OBJECTIVE

Unregulated stimulant use is rising globally, though trends in use of cocaine and crystal methamphetamine (CM), the two most commonly used unregulated stimulants in North America, are poorly characterized in many settings. In this study we examined patterns and associations between the injection of cocaine and CM over time in an urban Canadian setting.

METHODS

The study collected data from two prospective cohorts of people who inject drugs in Vancouver, Canada, between 2008 and 2018. We applied a time series analysis, using multivariable linear regression to detect relationships between reported CM and cocaine injection and year, controlling for covariates. The study used cross-correlation to evaluate the relative trajectories of each substance over time.

RESULTS

Among 2056 participants, per annum rates of reported injection cocaine use declined significantly over the duration of this study from 45 % to 18 % (p < 0.001), while rates of CM injection increased from 17 % to 32 % (p < 0.001). Multivariable linear regression showed that recent CM injection was negatively associated with recent cocaine injection (β = -0.609, 95 % CI = -0.750, -0.467). Cross-correlation demonstrated that injection CM use was associated with a decrease in the likelihood of cocaine injection 12 months later (p = 0.002).

CONCLUSIONS

These findings demonstrate an epidemiological shift in patterns of injection stimulant use, with rising CM injection associated with a corresponding decrease in cocaine injection over time. Strategies are urgently needed that help to treat and reduce harm among the growing population of people who inject CM.

A Pilot Randomized Control Study on Effect Brief Heart Rate Variability Biofeedback as a Complementary Treatment in Men with Methamphetamine Use Disorder

The aims of this study were to investigate the efficacy of heart rate variability biofeedback (HRVBFB) intervention in terms of reducing craving, severity of dependence, and rate of positive methamphetamine urine testing in men taking part in a methamphetamine use disorder outpatient treatment program. Sixty-one adult men received either HRVBFB treatment plus treatment as usual (TAU) over four weeks or TAU only. Men receiving HRVBFB showed significantly greater reductions in craving, dependence severity, and the rate of positive methamphetamine urine testing at the end of the intervention and four weeks of follow-up. The analyses further showed that the levels of craving and dependence severity at treatment entry were predictive of changes in craving and dependence severity at the end of treatment and follow-up, respectively. The baseline status of a positive methamphetamine urine test only predicted a positive methamphetamine urine test at the end of treatment, not at the end of the follow-up period. Our results showed HRVBFB intervention has merits as an adjunct treatment to ameliorate cravings and reduce the severity of dependence experienced by persons with methamphetamine use disorder. An added value of HRVBFB intervention is the fact that it can be easily and affordably implemented in everyday life.

Environmental influence on the preclinical evaluation of substance use disorder therapeutics

Substance use disorders (SUD) develop as a result of complex interactions between the environment, the subject, and the drug of abuse. Preclinical basic research investigating each of these tripartite components of SUD individually has resulted in advancements in our fundamental knowledge regarding the progression from drug abuse to SUD and severe drug addiction and the underlying behavioral and neurobiological mechanisms. How these complex interactions between the environment, the subject, and the drug of abuse impact the effectiveness of candidate or clinically used medications for SUD has not been as extensively investigated. The focus of this chapter will address the current state of our knowledge how these environmental, subject, and pharmacological variables have been shown to impact candidate or clinical SUD medication evaluation in preclinical research using drug self-administration procedures as the primary dependent measure. The results discussed in this chapter highlight the importance of considering environmental variables such as the schedule of reinforcement, concurrent availability of alternative nondrug reinforcers, and experimental housing conditions in the context of SUD therapeutic evaluation. The thesis of this chapter is that improved understanding of environmental variables in the context of SUD research will facilitate the utility of preclinical drug self-administration studies in the evaluation and development of candidate SUD therapeutics.

Psychostimulant Use Disorder, an Unmet Therapeutic Goal: Can Modafinil Narrow the Gap?

The number of individuals affected by psychostimulant use disorder (PSUD) has increased rapidly over the last few decades resulting in economic, emotional, and physical burdens on our society. Further compounding this issue is the current lack of clinically approved medications to treat this disorder. The dopamine transporter (DAT) is a common target of psychostimulant actions related to their use and dependence, and the recent availability of atypical DAT inhibitors as a potential therapeutic option has garnered popularity in this research field. Modafinil (MOD), which is approved for clinical use for the treatment of narcolepsy and sleep disorders, blocks DAT just like commonly abused psychostimulants. However, preclinical and clinical studies have shown that it lacks the addictive properties (in both behavioral and neurochemical studies) associated with other abused DAT inhibitors. Clinical availability of MOD has facilitated its off-label use for several psychiatric disorders related to alteration of brain dopamine (DA) systems, including PSUD. In this review, we highlight clinical and preclinical research on MOD and its R-enantiomer, R-MOD, as potential medications for PSUD. Given the complexity of PSUD, we have also reported the effects of MOD on psychostimulant-induced appearance of several symptoms that could intensify the severity of the disease (i.e., sleep disorders and impairment of cognitive functions), besides the potential therapeutic effects of MOD on PSUD.

A randomized comparison of 4 vs. 16 weeks of psychosocial treatment for stimulant users

Controlled studies provide little empirical evidence to inform clinical recommendations for the optimal duration (i.e., "dosage") of psychosocial treatment for substance use disorders (SUDs). The current study prospectively examined the relationships among treatment dosage, participant adherence to the treatment regimen, and treatment outcomes in a population of adults with stimulant use disorder (cocaine and/or methamphetamine). The study randomly assigned eighty-five participants to receive either 4 weeks or 16 weeks of standardized outpatient treatment. The treatment consisted of cognitive behavioral therapy (CBT) and content covered was identical for each condition; only the planned duration of participation differed. Although both groups reduced stimulant use over time, participants in the 16-week condition were significantly more likely than those in the 4-week condition to provide stimulantnegative urine specimens 26 and 52 weeks following randomization. Participant adherence to treatment correlated significantly with drug-use outcomes: we observed a greater likelihood of stimulant-negative urine tests among those who completed treatment, irrespective of group assignment. Both the number of sessions attended and the percentage of prescribed sessions attended were associated with reductions in stimulant-use frequency 26 and 52 weeks after admission.

The Effect of High-frequency Repetitive Transcranial Magnetic Stimulation on Reducing Depression and Anxiety in Methamphetamine Users

BACKGROUND

Methamphetamine use has been associated with higher rates of depression and anxiety. The mesocorticolimbic dopaminergic reward system seems to play a crucial role in inducing depression and anxiety in methamphetamine users. High-frequency repetitive transcranial magnetic stimulation (rTMS) has been shown to alter dopaminergic neurotransmission considering the acute rewarding and reinforcing effects in the subcortical structure. The aim of this study was to investigate the efficacy of rTMS in reducing depression and anxiety symptoms in methamphetamine users.

METHODS

In a single-subject method with concurrent multiple baseline designs, in 2017, in Iran, eight methamphetamine users were included, which compared 15 days of active versus placebo stimulation and control group. Two subjects received rTMS on the right dorsolateral prefrontal cortex (DLPFC) and two subjects received rTMS on the left DLPFC. We carried out the measurement using the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) before, during, and after 15 and 30 days of the procedure.

FINDINGS

Right and left DLPFC stimulation significantly reduced depression and anxiety, but the reduction of depression and anxiety by the right DLPFC stimulation was noticeable in this study.

CONCLUSION

High-frequency rTMS is useful for the treatment of depression and anxiety in methamphetamine users.

The therapeutic effects of methylphenidate and matrix-methylphenidate on addiction severity, craving, relapse and mental health in the methamphetamine use disorder

Background

Little evidence has examined the therapeutic effects of methylphenidate (MPH) and Matrix Model treatment on addiction severity, craving, relapse and mental health in people who use methamphetamine (PWUM). This study was conducted to determine the effects of MPH, Matrix Model treatment, and Matrix-MPH on addiction severity, craving, relapse and mental health in PWUM.

Methods

This clinical trial was conducted among 100 patients with METH users. Participants were randomly divided into four groups who received: 1) 22 sessions of 45-min, twice a week for Matrix Model treatment (n = 25); 2) MPH 10 mg/day in the first month, 7.5 mg/day in the second month and 5 mg/day in the third month (n = 25); 3) Matrix Model treatment combined with MPH (n = 25); 4) control group (n = 25) for 12 weeks. Addiction severity, craving, relapse and mental status were evaluated at baseline and end-of-trial.

Results

Matrix Model treatment combined with MPH significantly reduced MA craving (P < 0.001) and addiction severity (P < 0.001). In addition, Matrix Model treatment combined with MPH resulted in a significant increase of mental health (P = 0.001), compared with Matrix Model treatment, MPH, and control group. Also, negative METH urine test significantly increased in the Matrix Model treatment combined with MPH group compared with the other groups (P < 0.001).

Conclusions

In conclusion, Matrix Model treatment combined with MPH for 12 weeks had beneficial effects on addiction severity, craving, relapse, and mental health in PWUM, compared with Matrix Model treatment, MPH, and control group.

Trial registration

This study was retrospectively registered in the Iranian website (www.irct.ir) for clinical trials registration (http://www.irct.ir: IRCT20171105037245N1). Registration date: 9 December 2017.

Adaptation of contingency management for stimulant use disorder during the COVID-19 pandemic

The current coronavirus disease (COVID-19) pandemic has rapidly spread across the world. Individuals with stimulant use disorder are a vulnerable population, who are particularly at risk of negative outcomes during this pandemic due to several risk factors, including mental and physical comorbidities, weakened immune responses, high-risk behaviors, and barriers to healthcare access. Engaging patients with stimulant use disorder in regular treatment has become even more difficult during this pandemic, which has resulted in many cuts to addiction treatment programs. The most effective treatment options for stimulant use disorder are psychosocial interventions, which rely heavily on in-person interactions, posing an added challenge during physical distancing. In particular, contingency management (CM) is a behavioral therapy that utilizes tangible reinforcements to incentivize targeted behavior changes, and is an effective treatment intervention used for stimulant use disorder. This paper highlights the treatment challenges for individuals with stimulant use disorder and the importance of adapting CM programs during COVID-19. We present strategies for how CM can be adapted and its role expanded in a safe way during the COVID-19 pandemic to help prevent infection spread, stimulant use relapse, and worsened psychosocial consequences.

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Stimulant users face increased risk of relapse and infection during a pandemic.

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Contingency management is an effective treatment for stimulant use disorder.

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Contingency management can be adapted to mitigate negative outcomes of COVID-19.

Non-pharmacological interventions for methamphetamine use disorder: a systematic review

BACKGROUND

Methamphetamine (METH) use is on the rise globally, with the number of treatment seekers increasing exponentially across the globe. Evidence-based therapies are needed to meet rising treatment needs. This systematic review intends to appraise the existing evidence to identify effective non-pharmaceutical approaches for the treatment of METH use disorder.

METHODS

Five electronic bibliographic databases-Ovid (Medline), Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Web of Science and PsycINFO- were searched to identify relevant studies that were published between January 1995 to February 2020. Studies were selected and assessed by two independent reviewers. A systematic review of data from both randomised control trials (RCT) and non-RCTs was conducted to appraise the evidence.

RESULTS

A total of 44 studies were included in the review. Behavioural interventions, i.e. cognitive behavioural therapy (CBT), contingency management (CM), exercise, residential rehabilitation based therapies, repetitive transcranial magnetic stimulation (rTMS), and matrix model demonstrated treatment efficacy in promoting abstinence, reducing methamphetamine use or craving in the participants. While CM interventions showed the strongest evidence favouring the outcomes assessed, tailored CBT alone or with CM was also effective in the target population.

CONCLUSIONS

Behavioural interventions should be considered as the first line of treatment for methamphetamine use disorder. Future studies should address the longevity of the effects, and limitations due to smaller sample sizes and high dropout rates to enable better assessment of evidence.

Neuroplastic changes in resting-state functional connectivity after rTMS intervention for methamphetamine craving

Amphetamine-type stimulants are the second most commonly abused illicit drug worldwide, with no effective medical treatments currently available. Previous studies have demonstrated that high frequency repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) reduced cue-induced craving in patients with methamphetamine dependence. However, the neuroplastic mechanism underlying rTMS intervention in methamphetamine users remains to be elucidated. Sixty participants (40 males) with severe methamphetamine use disorder according to DSM-5 were randomized to receive either intermittent theta burst protocols (iTBS) (short bursts of 50 Hz rTMS repeated at a rate in the theta range (5 Hz), 2-sec on, 8-sec off for 5 min; 900 pulses) or sham rTMS over the DLPFC over four weeks (20 daily sessions). Resting state functional connectivity magnetic resonance imaging was acquired before and after rTMS intervention. Participants received drug related cue exposure and rated their craving before and after stimulation. Seed-based functional connectivity analysis was performed to probe rTMS-induced neuroplastic reorganization of brain functional networks. Results showed that twenty daily rTMS sessions decreased craving, increased functional connectivity between left DLPFC and inferior parietal lobule, and decreased functional connectivity between insula and inferior parietal lobule, medial temporal lobe and precuneus. Moreover, the increase of functional connectivity between DLPFC and inferior parietal lobule correlated with craving reduction. This study suggests that neuroplastic changes of frontoparietal functional connectivity contributes to craving reduction, shedding light on the therapeutic effect of rTMS on methamphetamine use disorder. This article is part of the special issue on Stress, Addiction and Plasticity.

Inhibitory-control training for cocaine use disorder and contingency management for clinic attendance: A randomized pilot study of feasibility, acceptability and initial efficacy

BACKGROUND

Cocaine abusers have impaired inhibitory Cocaine use is associated with impaired inhibitory control. This study determined the feasibility, acceptability, and initial efficacy of inhibitory-control training to cocaine or neutral images in cocaine use disorder patients.

METHODS

Participants were randomly assigned to inhibitory-control training to cocaine (N = 20) or neutral (N = 20) images. Feasibility was assessed by percent of patients eligible for participation after a behavioral qualification session, time-to-target enrollment, percent of clinic visits attended, percent of participants who completed 80 % or more training sessions, and percent of follow-up visits attended. Acceptability was determined using a Treatment Acceptability Questionnaire. Initial efficacy was determined during training and a follow-up phase with urine samples tested qualitatively and quantitatively for cocaine. Participants in both conditions received monetary incentives delivered on an escalating schedule for clinic attendance.

RESULTS

The groups were well matched and no differences on demographic or substance use variables were observed. Attendance was stable during the treatment period with high overall attendance in both groups (average sessions attended: cocaine image group = 97 %; neutral image group = 90 %). No group differences were observed in the percentage of follow-up sessions attended (95 % for the cocaine-image group; 88 % of neutral-image group). Ratings on the Treatment Acceptability Questionnaire were high (i.e., mean scores ≥ 80 for all items rated on 101-unit visual analog scales). Participants in the cocaine- and neutral-image conditions did not differ significantly in terms of cocaine use during the training nor follow-up phase. Inhibitory-control training improved stop signal performance but not delay discounting.

CONCLUSION

The procedures were feasible and acceptable. Inhibitory-control training to cocaine images did not reduce cocaine use relative to the neutral image training condition. The inability to detect significant differences in cocaine use across the groups is not surprising given the small sample size. More research is needed to determine the utility of inhibitory-control training for cocaine use disorder. Future trials should determine whether inhibitory-control training to cocaine images augments the efficacy of other behavioral interventions.

HIV and Substance Use Disorder: Role of the HIV Physician

The ongoing syndemic of substance use disorder and human immunodeficiency virus infection threatens progress made in preventing new infections and improving outcomes among those infected. To address this challenge effectively, human immunodeficiency virus physicians must take an increased role in the screening, diagnosis, and treatment of substance use disorders. Such treatment decreases human immunodeficiency virus risk behaviors and improves human immunodeficiency virus and substance use disorder-related outcomes. An effective response to this syndemic requires increased access to adjuvant interventions and a radical movement away from the current stigmatization and criminalization of those suffering from substance use disorders.

Treatment of amphetamine abuse/use disorder: a systematic review of a recent health concern

OBJECTIVES

The study systematically reviewed the effectiveness of pharmacological treatments alone or combined with brief cognitive-behavioural therapy (BCBT) for treating Iranian amphetamine abusers. The secondary aim was to review the efficacy of BCBT alone or combined with pharmacological treatments for treating amphetamine abusers in the world.

EVIDENCE ACQUISITION

Published trials were considered for inclusion. The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Web of Science, MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, Cochrane Drugs and Alcohol Group's Specialised Register of Trials, Embase, CINAHL, Scopus, PsychINFO, Iran Medex, Magiran and the Scientific Information Database were searched (January 2001 to March 2019). The reference lists of included studies were hand searched for more information. A systematic literature search in eight databases produced 10 trials.

RESULTS

Risperidone reduced positive psychotic symptoms while aripiprazole reduced negative psychotic symptoms. Methylphenidate reduced craving and depression compared with placebo. Topiramate reduced addiction severity and craving for methamphetamine abuse compared with placebo. Buprenorphine reduced methamphetamine craving more than methadone. Haloperidol and risperidone reduced psychosis. Riluzole reduced craving, withdrawal, and depression compared with placebo. Abstinence from amphetamine or reduction in amphetamine abuse was confirmed in four BCBT studies and one study which applied BCBT with a pharmacological treatment which were stable between two and 12-months. Other changes in BCBT studies were as follows: reduced polydrug use; drug injection, criminality and severity of amphetamine dependence at six-month follow-up; improved general functioning; mental health; stage of change as well as improved motivation to change in a pharmacological + BCBT study.

CONCLUSION

A review of trials indicates that pharmacological treatments and BCBT in a research setting outperform control conditions in treating amphetamines abuse and associated harms. Large-scale studies should determine if both treatments can be effective in clinical settings.

Cognitive-behavioural treatment for amphetamine-type stimulants (ATS)-use disorders

Background

Amphetamine-type stimulants (ATS) refer to a group of synthetic stimulants including amphetamine, methamphetamine, 3,4-methylenedioxy-methamphetamine (MDMA) and related substances. ATS are highly addictive and prolonged use may result in a series of mental and physical symptoms including anxiety, confusion, insomnia, mood disturbances, cognitive impairments, paranoia, hallucinations and delusion.Currently there is no widely accepted treatment for ATS-use disorder. However, cognitive-behavioural treatment (CBT) is the first-choice treatment. The effectiveness of CBT for other substance-use disorders (e.g. alcohol-, opioid- and cocaine-use disorders) has been well documented and as such this basic treatment approach has been applied to the ATS-use disorder.

Objectives

To investigate the efficacy of cognitive-behavioural treatment for people with ATS-use disorder for reducing ATS use compared to other types of psychotherapy, pharmacotherapy, 12-step facilitation, no intervention or treatment as usual.

Search methods

We identified randomised controlled trials (RCT) and quasi-RCTs comparing CBT for ATS-use disorders with other types of psychotherapy, pharmacotherapy, 12 step facilitation or no intervention. We searched the Cochrane Drugs and Alcohol Group Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE via PubMed, Embase and five other databases up to July 2018. In addition, we examined reference lists of eligible studies and other systematic reviews. We contacted experts in the field.

Selection criteria

Eligibility criteria consisted of RCTs and quasi-RCTs comparing CBT versus other types of interventions with adult ATS users (aged 18 years or older) diagnosed by any explicit diagnostic system. Primary outcomes included abstinence rate and other indicators of drug-using behaviours.

Data collection and analysis

We used standard methodological procedures expected by Cochrane.

Main results

Only two studies met the eligibility criteria. Both studies were at low risk of selection bias and reporting bias. In one study, almost half of participants in the intervention group dropped out and this study was at high risk of attrition bias. The studies compared a single session of brief CBT or a web-based CBT to a waiting-list control (total sample size across studies of 129). Results were mixed across the studies. For the single-session brief CBT study, two out of five measures of drug use produced significant results, percentage of abstinent days in 90 days (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.02 to 2.11) and dependence symptoms (standardised mean difference (SMD) -0.59, 95% CI-1.16 to-0.02). Little confidence could be placed in the results from this study give the small sample size (25 participants per group) and corresponding large CIs around the observed effects. For the web-based CBT, there was no significant difference across different outcomes. Neither study reported adverse effects. The meta-analytic mean across these two trials for drug use was not significant (SMD -0.28, 95% CI-0.69 to 0.14). In summary, overall quality of evidence was low and there was insufficient evidence to conclude that CBT is effective, or ineffective, at treating ATS use.

Authors' conclusions

Currently, there is not enough evidence to establish the efficacy of CBT for ATS-use disorders because of a paucity of high-quality research in this area.

Cognitive-behavioural treatment for amphetamine-type stimulants (ATS)-use disorders

BACKGROUND

Amphetamine-type stimulants (ATS) refer to a group of synthetic stimulants including amphetamine, methamphetamine, 3,4-methylenedioxy-methamphetamine (MDMA) and related substances. ATS are highly addictive and prolonged use may result in a series of mental and physical symptoms including anxiety, confusion, insomnia, mood disturbances, cognitive impairments, paranoia, hallucinations and delusion.Currently there is no widely accepted treatment for ATS-use disorder. However, cognitive-behavioural treatment (CBT) is the first-choice treatment. The effectiveness of CBT for other substance-use disorders (e.g. alcohol-, opioid- and cocaine-use disorders) has been well documented and as such this basic treatment approach has been applied to the ATS-use disorder.

OBJECTIVES

To investigate the efficacy of cognitive-behavioural treatment for people with ATS-use disorder for reducing ATS use compared to other types of psychotherapy, pharmacotherapy, 12-step facilitation, no intervention or treatment as usual.

SEARCH METHODS

We identified randomised controlled trials (RCT) and quasi-RCTs comparing CBT for ATS-use disorders with other types of psychotherapy, pharmacotherapy, 12 step facilitation or no intervention. We searched the Cochrane Drugs and Alcohol Group Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE via PubMed, Embase and five other databases up to July 2018. In addition, we examined reference lists of eligible studies and other systematic reviews. We contacted experts in the field.

SELECTION CRITERIA

Eligibility criteria consisted of RCTs and quasi-RCTs comparing CBT versus other types of interventions with adult ATS users (aged 18 years or older) diagnosed by any explicit diagnostic system. Primary outcomes included abstinence rate and other indicators of drug-using behaviours.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Only two studies met the eligibility criteria. Both studies were at low risk of selection bias and reporting bias. In one study, almost half of participants in the intervention group dropped out and this study was at high risk of attrition bias. The studies compared a single session of brief CBT or a web-based CBT to a waiting-list control (total sample size across studies of 129). Results were mixed across the studies. For the single-session brief CBT study, two out of five measures of drug use produced significant results, percentage of abstinent days in 90 days (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.02 to 2.11) and dependence symptoms (standardised mean difference (SMD) -0.59, 95% CI -1.16 to -0.02). Little confidence could be placed in the results from this study give the small sample size (25 participants per group) and corresponding large CIs around the observed effects. For the web-based CBT, there was no significant difference across different outcomes. Neither study reported adverse effects. The meta-analytic mean across these two trials for drug use was not significant (SMD -0.28, 95% CI -0.69 to 0.14). In summary, overall quality of evidence was low and there was insufficient evidence to conclude that CBT is effective, or ineffective, at treating ATS use.

AUTHORS' CONCLUSIONS

Currently, there is not enough evidence to establish the efficacy of CBT for ATS-use disorders because of a paucity of high-quality research in this area.

Applying behavioral activation to sustain and enhance the effects of contingency management for reducing stimulant use among individuals with HIV infection

There is a high prevalence of stimulant use among HIV-infected individuals, which is associated with suboptimal antiretroviral therapy (ART) adherence, HIV treatment interruptions, detectable HIV viral load, and transmission of HIV via increased sexual risk behavior. Contingency management (CM) is an initially effective treatment for stimulant use. However, the effects of CM are not sustained after the active intervention has ended. One potential contributor to the intractability of existing treatments may be a lack of attention to replacement activities or the role of depressed mood. Behavioral activation (BA) is an evidence-based approach for depression that involves identifying and participating in pleasurable, goal-directed activities. As a potential approach to address the CM rebound effect - informed by our formative qualitative research with the participant population - we conducted an open pilot trial of an intervention combining CM-BA for HIV-infected individuals with stimulant use disorder. Participants completed weekly BA therapy sessions (10-16 sessions) and thrice-weekly toxicology screenings (12 weeks); contingencies were rewarded for negative toxicology tests to support reengagement into positive life activities. Major assessments were conducted at baseline, 3-, and 6-months. Toxicology screening was repeated prior to the 6-month assessment. Eleven participants with stimulant use disorder enrolled; 7 initiated treatment and completed the full intervention. The mean age was 46 (SD = 5.03) and 14% identified as a racial/ethnic minority. Of the completers, the mean change score in self-reported stimulant use within the past 30 days (within-person change; reduction in self-reported stimulant use) was 4.14 days at 3 months and 5.0 days at 6 months [Cohen's d = 0.89]. The mean change score in weekly toxicology screens (reduction in positive toxicology screens) was .71 at 3 months and 1 at 6 months [Cohen's d = 1.05]. Exit interviews indicated that the integrated intervention was well received and acceptable. This study provides preliminary evidence that a combined CM-BA intervention for this population was feasible (100% retention at 6-months), acceptable (100% of intervention sessions attended; participants rated the intervention 'acceptable' or 'very acceptable'), and may be an option to augment the potency and sustained impact of CM for this population. Future pilot testing using a randomized controlled design is warranted.

The role of prevention strategies in achieving HCV elimination in Canada: what are the remaining challenges?

Background

The worldwide economic, health, and social consequences of drug use disorders are devastating. Injection drug use is now a major factor contributing to hepatitis C virus (HCV) transmission globally, and it is an important public health concern.

Methods

This article presents a narrative review of scientific evidence on public health strategies for HCV prevention among people who inject drugs (PWID) in Canada.

Results

A combination of public health strategies including timely HCV detection and harm reduction (mostly needle and syringe programmes and opioid substitution therapy) have helped to reduce HCV transmission among PWID. The rising prevalence of pharmaceutical opioid and methamphetamine use and associated HCV risk in several Canadian settings has prompted further innovation in harm reduction, including supervised injection facilities and low-threshold opioid substitution therapies. Further significant decreases in HCV incidence and prevalence, and in corresponding disease burden, can only be accomplished by reducing transmission among high-risk persons and enhancing access to HCV treatment for those at the greatest risk of disease progression or viral transmission. Highly effective and tolerable direct-acting antiviral therapies have transformed the landscape for HCV-infected patients and are a valuable addition to the prevention toolkit. Curing HCV-infected persons, and thus eliminating new infections, is now a real possibility.

Conclusions

Prevention strategies have not yet ended HCV transmission, and sharing of injecting equipment among PWID continues to challenge the World Health Organization goal of eliminating HCV as a global public health threat by 2030. Future needs for research, intervention implementation, and uptake in Canada are discussed.

Neuropsychological comparisons of cocaine versus methamphetamine users: A research synthesis and meta-analysis

BACKGROUND

Previous meta-analytical research examining cocaine and methamphetamine separately suggests potentially different neuropsychological profiles associated with each drug. In addition, neuroimaging studies point to distinct structural changes that might underlie differences in neuropsychological functioning.

OBJECTIVES

This meta-analysis compared the effect sizes identified in cocaine versus methamphetamine studies across 15 neuropsychological domains.

METHOD

Investigators searched and coded the literature examining the neuropsychological deficits associated with a history of either cocaine or methamphetamine use. A total of 54 cocaine and 41 methamphetamine studies were selected, yielding sample sizes of 1,718 and 1,297, respectively. Moderator analyses were conducted to compare the two drugs across each cognitive domain.

RESULTS

Data revealed significant differences between the two drugs. Specifically, studies of cocaine showed significantly larger effect-size estimates (i.e., poorer performance) in verbal working memory when compared to methamphetamine. Further, when compared to cocaine, methamphetamine studies demonstrated significantly larger effect sizes in delayed contextual verbal memory and delayed visual memory.

CONCLUSION

Overall, cocaine and methamphetamine users share similar neuropsychological profiles. However, cocaine appears to be more associated with working memory impairments, which are typically frontally mediated, while methamphetamine appears to be more associated with memory impairments that are linked with temporal and parietal lobe dysfunction.

Influencing Antibody-Mediated Attenuation of Methamphetamine CNS Distribution through Vaccine Linker Design

Active vaccination examining a single hapten engendered with a series of peptidic linkers has resulted in the production of antimethamphetamine antibodies. Given the limited chemical complexity of methamphetamine, the structure of the linker species embedded within the hapten could have a substantial effect on the ultimate efficacy of the resulting vaccines. Herein, we investigate linker effects by generating a series of methamphetamine haptens that harbor a linker with varying amino acid identity, peptide length, and associated carrier protein. Independent changes in each of these parameters were found to result in alterations in both the quantity and quality of the antibodies induced by vaccination. Although it was found that the consequence of the linker design was also dependent on the identity of the carrier protein, we demonstrate overall that the inclusion of a short, structurally simple, amino acid linker benefits the efficacy of a methamphetamine vaccine in limiting brain penetration of the free drug.

Outcomes from a Homegrown HIV Prevention Program for Extremely High-risk, Substance-using Men who have Sex with Men with Multiple Health Disparities

From February 2010 through December 2014, 585 substance-using MSM were enrolled into a "homegrown" risk reduction intervention. Participants evidenced significant iterative factor reductions in the odds of substance use including alcohol (AOR=0.79) and marijuana (AOR=0.78; both p≤0.05) and marginally significant reductions in the odds of methamphetamine use (AOR=0.83; p≤0.07). Participants also evidenced significant reductions in sexual risks including the odds of reporting drug/alcohol use before or during sex (AOR=0.80) and of condomless anal intercourse (AOR=0.72; all significant at p≤0.05). Results demonstrate that the homegrown intervention was effective at reducing HIV risk behaviors among high-risk MSM.

The Influence of Retention, Turnover, and Alliance on Process and Outcomes in Rolling Group Psychotherapy for Cocaine Disorder

A longitudinal repeated measures design was used to investigate the influence of treatment retention, and membership turnover on individual outcomes, and the relationship between individual-level and group-level therapeutic alliance in rolling group psychotherapy for individuals with cocaine abuse disorder. Eighteen patients were studied; data were collected prior to therapy and then monthly for 24 months. Patient outcomes and process were assessed. Improvements in symptoms and psychological functioning were associated with retention in psychotherapy. Membership turnover had a negative influence on symptoms. Development of an individual alliance was affected by the development of group-level therapeutic alliance, but not by time spent in therapy.

Psychosocial interventions for psychostimulant misuse

BACKGROUND

Psychostimulant misuse is a continuously growing medical and social burden. There is no evidence proving the efficacy of pharmacotherapy. Psychosocial interventions could be a valid approach to help patients in reducing or ceasing drug consumption.

OBJECTIVES

To assess the effects of psychosocial interventions for psychostimulant misuse in adults.

SEARCH METHODS

We searched the Cochrane Drugs and Alcohol Group Specialised Register (via CRSLive); Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; CINAHL; Web of Science and PsycINFO, from inception to November 2015. We also searched for ongoing and unpublished studies via ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (apps.who.int/trialsearch/).All searches included non-English language literature. We handsearched references of topic-related systematic reviews and the included studies.

SELECTION CRITERIA

We included randomised controlled trials comparing any psychosocial intervention with no intervention, treatment as usual (TAU) or a different intervention in adults with psychostimulant misuse or dependence.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included a total of 52 trials (6923 participants).The psychosocial interventions considered in the studies were: cognitive behavioural therapy (19 studies), contingency management (25 studies), motivational interviewing (5 studies), interpersonal therapy (3 studies), psychodynamic therapy (1 study), 12-step facilitation (4 studies).We judged most of the studies to be at unclear risk of selection bias; blinding of personnel and participants was not possible for the type of intervention, so all the studies were at high risk of performance bias with regard to subjective outcomes; the majority of studies did not specify whether the outcome assessors were blind. We did not consider it likely that the objective outcomes were influenced by lack of blinding.The comparisons made were: any psychosocial intervention versus no intervention (32 studies), any psychosocial intervention versus TAU (6 studies), and one psychosocial intervention versus an alternative psychosocial intervention (13 studies). Five of included studies did not provide any useful data for inclusion in statistical synthesis.We found that, when compared to no intervention, any psychosocial treatment: reduced the dropout rate (risk ratio (RR): 0.83, 95% confidence interval (CI) 0.76 to -0.91, 24 studies, 3393 participants, moderate quality evidence); increased continuous abstinence at the end of treatment (RR: 2.14, 95% CI 1.27 to -3.59, 8 studies, 1241 participants, low quality evidence); did not significantly increase continuous abstinence at the longest follow-up (RR: 2.12, 95% CI 0.77 to -5.86, 4 studies, 324 participants, low quality evidence); significantly increased the longest period of abstinence: (standardised mean difference (SMD): 0.48, 95% CI 0.34 to 0.63, 10 studies, 1354 participants, high quality evidence). However, it should be noted that the in the vast majority of the studies in this comparison the specific psychosocial treatment assessed in the experimental arm was given in add on to treatment as usual or to another specific psychosocial or pharmacological treatment which was received by both groups. So, many of the control groups in this comparison were not really untreated. Receiving some amount of treatment is not the same as not receiving any intervention, so we could argue that the overall effect of the experimental psychosocial treatment could be smaller if given in add on to TAU or to another intervention than if given to participants not receiving any intervention; this could translate to a smaller magnitude of the effect of the psychosocial intervention when it is given in add on.When compared to TAU, any psychosocial treatment reduced dropout rate (RR: 0.72, 95% CI 0.59 to 0.89, 6 studies, 516 participants, moderate quality evidence), did not increase continuous abstinence at the end of treatment (RR: 1.27, 95% CI 0.94 to 1.72, 2 studies, 224 participants, low quality evidence), did not increase longest period of abstinence (MD -3.15 days, 95% CI -10.35 to 4.05, 1 study, 110 participants, low quality evidence). No studies in this comparison assessed the outcome of continuous abstinence at longest follow-up.There were few studies comparing two or more psychosocial interventions, with small sample sizes and considerable heterogeneity in terms of the types of interventions assessed. None reported significant results.None of the studies reported harms related to psychosocial interventions.

AUTHORS' CONCLUSIONS

The addition of any psychosocial treatment to treatment as usual (usually characterised by group counselling or case management) probably reduces the dropout rate and increases the longest period of abstinence. It may increase the number of people achieving continuous abstinence at the end of treatment, although this might not be maintained at longest follow-up. The most studied and the most promising psychosocial approach to be added to treatment as usual is probably contingency management. However, the other approaches were only analysed in a few small studies, so we cannot rule out the possibility that the results were not significant because of imprecision. When compared to TAU, any psychosocial treatment may improve adherence, but it may not improve abstinence at the end of treatment or the longest period of abstinence.The majority of the studies took place in the United States, and this could limit the generalisability of the findings, because the effects of psychosocial treatments could be strongly influenced by the social context and ethnicity. The results of our review do not answer the most relevant clinical question, demonstrating which is the most effective type of psychosocial approach.Further studies should directly compare contingency management with the other psychosocial approaches.

Clinical potential of methylphenidate in the treatment of cocaine addiction: a review of the current evidence

Background

Cocaine use continues to be a public health problem, yet there is no proven effective pharmacotherapy for cocaine dependence. A promising approach to treating cocaine dependence may be agonist-replacement therapy, which is already used effectively in the treatment of opioid and tobacco dependence. The replacement approach for cocaine dependence posits that administration of a long-acting stimulant medication should normalize the neurochemical and behavioral perturbations resulting from chronic cocaine use. One potential medication to be substituted for cocaine is methylphenidate (MPH), as this stimulant possesses pharmacobehavioral properties similar to those of cocaine.

Aim

To provide a qualitative review addressing the rationale for the use of MPH as a cocaine substitute and its clinical potential in the treatment of cocaine dependence.

Methods

We searched MEDLINE for clinical studies using MPH in patients with cocaine abuse/dependence and screened the bibliographies of the articles found for pertinent literature.

Results

MPH, like cocaine, increases synaptic dopamine by inhibiting dopamine reuptake. The discriminative properties, reinforcing potential, and subjective effects of MPH and cocaine are almost identical and, importantly, MPH has been found to substitute for cocaine in animals and human volunteers under laboratory conditions. When taken orally in therapeutic doses, its abuse liability, however, appears low, which is especially true for extended-release MPH preparations. Though there are promising data in the literature, mainly from case reports and open-label studies, the results of randomized controlled trials have been disappointing so far and do not corroborate the use of MPH as a substitute for cocaine dependence in patients without attention deficit hyperactivity disorder.

Conclusion

Clinical studies evaluating MPH substitution for cocaine dependence have provided inconsistent findings. However, the negative findings may be explained by specific study characteristics, among them dosing, duration of treatment, or sample size. This needs to be considered when discussing the potential of MPH as replacement therapy for cocaine dependence. Finally, based on the results, we suggest possible directions for future research.

Acute exercise ameliorates craving and inhibitory deficits in methamphetamine: An ERP study

This study aimed to determine the effect of acute exercise in the potential context of non-pharmacological intervention for methamphetamine (MA)-related craving; we additionally determine its effect on the inhibitory control induced by standard and MA-related tasks according to behavioral and neuroelectric measurements among MA-dependent individuals. The present study employed a within-subjects, counterbalanced design. A total of 24 participants who met the DSM-IV criteria for MA dependence were recruited. The craving level, reaction time, and response accuracy, as well as the event-related potential (ERP) components N2 and P3, were measured following exercise and the control treatment in a counterbalanced order. The exercise session consisted of an acute stationary cycle exercise at a moderate intensity, whereas the control treatment consisted of an active reading session. The self-reported MA craving was significantly attenuated during, immediately following, and 50min after the exercise session compared with the pre-exercise ratings, whereas the craving scores at these time points following exercise were lower than those for the reading control session. Acute exercise also facilitated inhibitory performance in both the standard and MA-related Go/Nogo tasks. A larger N2 amplitude, but not a larger P3 amplitude, was observed during both tasks in the exercise session and the Nogo condition compared with the reading control session and the Go condition. This is the first empirical study to demonstrate these beneficial effects of acute aerobic exercise at a moderate intensity on MA-related craving and inhibitory control in MA-dependent individuals. These results suggest a potential role for acute aerobic exercise in treating this specific type of substance abuse.

Methamphetamine: an update on epidemiology, pharmacology, clinical phenomenology, and treatment literature

BACKGROUND

Despite initial reports of a decline in use in the early 2000s, methamphetamine remains a significant public health concern with known neurotoxic and neurocognitive effects to the user. The goal of this review is to update the literature on methamphetamine use and addiction since its assent to peak popularity in 1990s.

METHODS

We first review recent epidemiological reports with a focus on methamphetamine accessibility, changes in use and disorder prevalence rates over time, and accurate estimates of the associated burden of care to the individual and society. Second, we review methamphetamine pharmacology literature with emphasis on the structural and functional neurotoxic effects associated with repeated use of the drug. Third, we briefly outline the findings on methamphetamine-related neurocognitive deficits as assessed via behavioral and neuroimaging paradigms. Lastly, we review the clinical presentation of methamphetamine addiction and the evidence supporting the available psychosocial and pharmacological treatments within the context of an addiction biology framework.

CONCLUSION

Taken together, this review provides a broad-based update of the available literature covering methamphetamine research over the past two decades and concludes with recommendations for future research.

Optimal neurocognitive, personality and behavioral measures for assessing impulsivity in cocaine dependence

BACKGROUND

Impulsivity may underlie the poor treatment retention and high relapse rates observed in cocaine-dependent persons. However, observed differences in measures of impulsivity between cocaine-dependent and healthy control participants often do not reach clinical significance, suggesting that the clinical relevance of these differences may be limited.

OBJECTIVES

To examine which measures of impulsivity (i.e. self-report impulsivity, self-report personality, neurocognitive testing) best distinguish cocaine-dependent and healthy control participants (i.e. showing differences at least 1.5 standard deviations [SD] from controls). Optimal measures were considered to demonstrate sufficient classification accuracy.

METHODS

Sixty-five recently abstinent cocaine-dependent and 25 healthy control participants were assessed using select neurocognitive tests and self-report questionnaires including the NEO Personality Inventory-Revised (NEO-PI-R), Temperament and Character Inventory (TCI), Barratt Impulsiveness Scale (BIS-11a), and the Frontal Systems Behavior Scale (FrSBe).

RESULTS

When corrected for years of education and gender, neurocognitive measures did not demonstrate clinically significant differences between cocaine-dependent and control participants. The personality measures TCI Purposefulness and Congruent Second Nature and NEO-PI-R Impulsiveness, and the self-rating measures FrSBe Disinhibition and BIS-11 Motor Impulsivity and Total successfully identified clinically meaningful elevations in impulsivity within cocaine-dependent participants (>1.5 SDs from controls). Furthermore, these measures achieved 84-93% accuracy in discriminating cocaine-dependent from control participants.

CONCLUSION

Clinically significant neurocognitive impairment in cocaine-dependent participants was not observed in this sample. As the BIS-11 or FrSBe are brief to administer, accurate, and have been shown to predict treatment retention and relapse, these measures appear to be optimal, relative to the personality measures, for examining trait impulsivity in cocaine dependence.

Treatment of Methamphetamine Dependence with Electroconvulsive Therapy (ECT) in Iran: A Critical Note

OBJEVTIVE

This comment article reviews the literature to explore whether the use of ECT for the treatment of methamphetamine dependence can be justified by scientific rationale and/or evidence.

METHOD

This article reviews the literature on the use of ECT in addictive disorders. It describes a patient with methamphetamine dependence treated with ECT. It then offers a historical review of the moral and ethical difficulties encountered in the treatment of addictive disorders. It proposes a dynamic understanding as to why clinicians might deploy such brutal actions in the face of hopeless and emotionally intense encounters.

RESULTS

We found no scientific evidence or justification for ECT as a treatment of methamphetamine dependence or as the first line treatment for methamphetamine-induced psychiatric comorbidities.

CONCLUSION

the current available evidence does not support using ECT for the treatment of addictive disorders, and hence is unethical, unacceptable and inhumane and warrants immediate social and political attention.

Characterizing longitudinal health state transitions among heroin, cocaine, and methamphetamine users

AIMS

Characterize longitudinal patterns of drug use careers and identify determinants of drug use frequency across cohorts of primary heroin, methamphetamine (MA) and cocaine users.

DESIGN

Pooled analysis of prospective cohort studies.

SETTINGS

Illicit drug users recruited from community, criminal justice and drug treatment settings in California, USA.

PARTICIPANTS

We used longitudinal data on from five observational cohort studies featuring primary users of heroin (N=629), cocaine (N=694) and methamphetamine (N=474). The mean duration of follow-up was 20.9 years.

MEASUREMENTS

Monthly longitudinal data was arranged according to five health states (incarceration, drug treatment, abstinence, non-daily and daily use). We fitted proportional hazards (PH) frailty models to determine independent differences in successive episode durations. We then executed multi-state Markov (MSM) models to estimate probabilities of transitioning between health states, and the determinants of these transitions.

FINDINGS

Across primary drug use types, PH frailty models demonstrated durations of daily use diminished in successive episodes over time. MSM models revealed primary stimulant users had more erratic longitudinal patterns of drug use, transitioning more rapidly between periods of treatment, abstinence, non-daily and daily use. MA users exhibited relatively longer durations of high-frequency use. Criminal engagement had a destabilizing effect on health state durations across drug types. Longer incarceration histories were associated with delayed transitions toward cessation.

CONCLUSIONS

PH frailty and MSM modeling techniques provided complementary information on longitudinal patterns of drug abuse. This information can inform clinical practice and policy, and otherwise be used in health economic simulation models, designed to inform resource allocation decisions.

Pregnancy and fetal loss reported by methamphetamine-using women

To better understand substance use disorder treatment needs of pregnant and parenting women who use methamphetamine (MA), this paper describes pregnancy histories and fetal losses for women who were treated for MA use (N = 153) with reference to a national sample, and describes their drug use, sexual risk behaviors, and mental health status. MA users reported an average of 4.6 total pregnancies and 2.1 fetal losses, whereas women in a general population survey reported 3.2 and 1.2, respectively. Higher numbers of pregnancies and fetal losses were correlated with specific substance abuse and mental health problems including early sexual abuse and cognitive problems. The combination of MA users' especially high numbers of pregnancies, fetal losses, and rates of risk behaviors suggest high social and health care costs for this population. Prenatal care may provide a vector through which women can be connected to risk reduction interventions and gender-responsive treatment services addressing substance use and mental health needs.

Psychostimulant addiction treatment

Treatment of psychostimulant addiction has been a major, and not fully met, challenge. For opioid addiction, there is strong evidence for the effectiveness of several medications. For psychostimulants, there is no corresponding form of agonist maintenance that has met criteria for regulatory approval or generally accepted use. Stimulant-use disorders remain prevalent and can result in both short-term and long-term adverse consequences. The mainstay of treatment remains behavioral interventions. In this paper, we discuss those interventions and some promising candidates in the search for pharmacological interventions. This article is part of the Special Issue entitled 'CNS Stimulants'.

Hyperactivation of the cognitive control network in cocaine use disorders during a multisensory Stroop task

BACKGROUND

It has been suggested that individuals with cocaine use disorders (chronic cocaine abusers, CCA) have impairments in cognitive control, which likely contribute to impairments in decision making around drug use and relapse. However, deficits in cognitive control have currently only been studied under conditions of unisensory stimulation, which may not be reflective of more realistic multisensory drug cues.

METHODS

The current study employed functional magnetic resonance imaging (fMRI) to measure neuronal activity during a multisensory numeric Stroop task.

RESULTS

Despite few differences in reaction time, recently abstinent CCA (N=14) exhibited increased activation in prefrontal cortex, striatum and thalamus during cognitive control relative to a group of carefully matched controls (N=16). Importantly, these neuronal differences were relatively robust in classifying patients from controls (approximately 90% accuracy) and evident during conditions of both low (slow stimulus presentation rate) and relatively high (faster stimulus presentation rate) cognitive demand. In addition, CCA also failed to deactivate the default-mode network during high frequency visual trials.

CONCLUSIONS

In summary, current results indicate compensatory activation within the cognitive control network in recently abstinent CCA to achieve similar levels of behavioral performance.

Attitudes toward methamphetamine use and HIV risk behavior in men who have sex with men

BACKGROUND AND OBJECTIVES

Methamphetamine use has been strongly associated with high-risk sexual behaviors, and its use has been increasing among men who have sex with men (MSM). Although the behavioral implications of methamphetamine use and sexual risk have been broadly examined, fewer studies have examined attitudes about methamphetamine use.

METHODS

This study investigates the relationship between personal beliefs regarding methamphetamine use, patterns of use, and sexual risk behaviors within a sample of MSM attending a gay pride event (N= 342).

RESULTS

A minority of MSM reported lifetime (27%) or recent (7%) methamphetamine use. Only a minority of MSM who had used methamphetamine believed that it enhanced sexual pleasure (32%) or incorporated methamphetamine use into their sexual activity (31%). Individuals who used methamphetamine during sexual activity were more likely to be recent users of the drug and more likely to engage in high-risk behaviors. A significant minority of participants endorsed items assessing the disinhibiting effects of methamphetamine including being less likely to use a condom (35%) and less selective in their choice of partners (26%).

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Results suggest that prevention efforts may benefit from targeting the minority of methamphetamine users who perceive methamphetamine as enhancing sexual activity and use it for this purpose.

The effect of stimulant use on antiviral treatment in an integrated hepatitis clinic

OBJECTIVE

The objective was to determine the impact of stimulant use on antiviral treatment for chronic hepatitis C patients in an integrated hepatitis clinic.

METHODS

A retrospective chart review of 449 consecutive patients seen in an integrated hepatitis clinic that included co-located mental health clinicians was performed. Psychiatric measures included drug use questionnaire, Beck Depression Inventory (BDI), Alcohol Use Disorders Identification Test-Consumption questions (AUDIT-C), urine drug screen and antiviral treatment outcomes. Patients with stimulant use were compared to patients with no drug use, other drug users and an unknown drug use group using χ(2) and analysis of variance tests.

RESULTS

Over 15% of hepatitis C patients presenting to the clinic were using stimulants. Stimulant users had higher BDI and AUDIT-C scores. They were more likely to be followed by a co-located mental health clinician than other groups and were just as likely to initiate and finish antiviral therapy.

CONCLUSIONS

Recent stimulant use is common in hepatitis C patients presenting to a hepatitis clinic. Stimulant users were more depressed and used alcohol to a greater degree than nonusers but were as likely to start antiviral therapy. An integrated mental health/medical care approach appears to be effective in addressing this difficult-to-treat population.

Modification of cocaine self-administration by buspirone (buspar®): potential involvement of D3 and D4 dopamine receptors

Converging lines of evidence indicate that elevations in synaptic dopamine levels play a pivotal role in the reinforcing effects of cocaine, which are associated with its abuse liability. This evidence has led to the exploration of dopamine receptor blockers as pharmacotherapy for cocaine addiction. While neither D1 nor D2 receptor antagonists have proven effective, medications acting at two other potential targets, D3 and D4 receptors, have yet to be explored for this indication in the clinic. Buspirone, a 5-HT1A partial agonist approved for the treatment of anxiety, has been reported to also bind with high affinity to D3 and D4 receptors. In view of this biochemical profile, the present research was conducted to examine both the functional effects of buspirone on these receptors and, in non-human primates, its ability to modify the reinforcing effects of i.v. cocaine in a behaviourally selective manner. Radioligand binding studies confirmed that buspirone binds with high affinity to recombinant human D3 and D4 receptors (∼98 and ∼29 nm respectively). Live cell functional assays also revealed that buspirone, and its metabolites, function as antagonists at both D3 and D4 receptors. In behavioural studies, doses of buspirone that had inconsistent effects on food-maintained responding (0.1 or 0.3 mg/kg i.m.) produced a marked downward shift in the dose-effect function for cocaine-maintained behaviour, reflecting substantial decreases in self-administration of one or more unit doses of i.v. cocaine in each subject. These results support the further evaluation of buspirone as a candidate medication for the management of cocaine addiction.

Interaction between behavioral and pharmacological treatment strategies to decrease cocaine choice in rhesus monkeys

Behavioral and pharmacotherapeutic approaches constitute two prominent strategies for treating cocaine dependence. This study investigated interactions between behavioral and pharmacological strategies in a preclinical model of cocaine vs food choice. Six rhesus monkeys, implanted with a chronic indwelling double-lumen venous catheter, initially responded under a concurrent schedule of food delivery (1-g pellets, fixed-ratio (FR) 100 schedule) and cocaine injections (0-0.1 mg/kg/injection, FR 10 schedule) during continuous 7-day treatment periods with saline or the agonist medication phenmetrazine (0.032-0.1 mg/kg/h). Subsequently, the FR response requirement for cocaine or food was varied (food, FR 100; cocaine, FR 1-100; cocaine, FR 10; food, FR 10-300), and effects of phenmetrazine on cocaine vs food choice were redetermined. Decreases in the cocaine FR or increases in the food FR resulted in leftward shifts in the cocaine choice dose-effect curve, whereas increases in the cocaine FR or decreases in the food FR resulted in rightward shifts in the cocaine choice dose-effect curve. The efficacy of phenmetrazine to decrease cocaine choice varied systematically as a function of the prevailing response requirements, such that phenmetrazine efficacy was greatest when cocaine choice was maintained by relatively low unit cocaine doses. These results suggest that efficacy of pharmacotherapies to modulate cocaine use can be influenced by behavioral contingencies of cocaine availability. Agonist medications may be most effective under contingencies that engender choice of relatively low cocaine doses.

A randomized, controlled, pilot trial of methylphenidate and cognitive-behavioral group therapy for cocaine dependence in heroin prescription

Cocaine dependence has proved difficult to treat, whether it occurs alone or in combination with opiate dependence. No intervention has been demonstrated to be uniquely effective. Patients might benefit most from combined pharmacotherapeutic and psychotherapeutic interventions. The present study sought to evaluate the feasibility, tolerability, and efficacy of methylphenidate (MP) and cognitive-behavioral group therapy (CBGT) for cocaine dependence in diacetylmorphine-maintained patients. Sixty-two cocaine-dependent diacetylmorphine-maintained patients participated in a dual-site, double-blind, placebo-controlled pilot trial with 4 treatment conditions. The participants were randomly assigned to receive MP or a placebo each combined with either CBGT or treatment as usual for 12 weeks. Methylphenidate 30 mg and a placebo in identical capsules were administered onsite twice daily under supervision in a fixed-dose regimen without titration. Manual-guided CBGT consisted of 12 weekly sessions. Participation in the CBGT sessions was voluntary. Primary outcome measures were retention in pharmacologic treatment, cocaine-free urine samples, self-reported cocaine use, and adverse effects. Urine screens were performed thrice weekly. Seventy-one percent of the participants completed the study protocol. Methylphenidate was well tolerated with similar retention rates compared with the placebo. No serious adverse effects occurred. No difference in cocaine-free urine screens was found across the 4 treatment groups. Self-reported cocaine use was reduced in all 4 study groups. Methylphenidate and CBGT did not provide an advantage over a placebo or treatment as usual in reducing cocaine use. There were no signs of additive benefits of MP and CBGT. Because of the small sample size, the results are preliminary.

Stimulant abuser groups to engage in 12-step: a multisite trial in the National Institute on Drug Abuse Clinical Trials Network

AIMS

The study evaluated the effectiveness of an 8-week combined group plus individual 12-step facilitative intervention on stimulant drug use and 12-step meeting attendance and service.

DESIGN

Multisite randomized controlled trial, with assessments at baseline, mid-treatment, end of treatment, and 3- and 6-month post-randomization follow-ups (FUs).

SETTING

Intensive outpatient substance treatment programs.

PARTICIPANTS

Individuals with stimulant use disorders (n = 471) randomly assigned to treatment as usual (TAU) or TAU into which the Stimulant Abuser Groups to Engage in 12-Step (STAGE-12) intervention was integrated.

MEASUREMENTS

Urinalysis and self-reports of substance use and 12-step attendance and activities.

INTERVENTION

Group sessions focused on increasing acceptance of 12-step principles; individual sessions incorporated an intensive referral procedure connecting participants to 12-step volunteers.

FINDINGS

Compared with TAU, STAGE-12 participants had significantly greater odds of self-reported stimulant abstinence during the active 8-week treatment phase; however, among those who had not achieved abstinence during this period, STAGE-12 participants had more days of use. STAGE-12 participants had lower Addiction Severity Index Drug Composite scores at and a significant reduction from baseline to the 3-month FU, attended 12-step meetings on a greater number of days during the early phase of active treatment, engaged in more other types of 12-step activities throughout the active treatment phase and the entire FU period, and had more days of self-reported service at meetings from mid-treatment through the 6-month FU.

CONCLUSIONS

The present findings are mixed with respect to the impact of integrating the STAGE-12 intervention into intensive outpatient drug treatment compared with TAU on stimulant drug use. However, the results more clearly indicate that individuals in STAGE-12 had higher rates of 12-step meeting attendance and were engaged in more related activities throughout both the active treatment phase and the entire 6-month FU period than did those in TAU.

A pilot trial of integrated behavioral activation and sexual risk reduction counseling for HIV-uninfected men who have sex with men abusing crystal methamphetamine

Crystal methamphetamine use is a major driver behind high-risk sexual behavior among men who have sex with men (MSM). Prior work suggests a cycle of continued crystal methamphetamine use and high-risk sex due to loss of the ability to enjoy other activities, which appears to be a side effect of this drug. Behavioral activation (BA) is a treatment for depression that involves learning to reengage in life's activities. We evaluated a novel intervention for crystal methamphetamine abuse and high-risk sex in MSM, incorporating 10 sessions of BA with integrated HIV risk reduction counseling (RR). Forty-four subjects were screened, of whom 21 met initial entry criteria. A total of 19 participants enrolled; 16 completed an open-phase study of the intervention. Behavioral assessments were conducted at baseline, 3 months postbaseline, and 6 months postbaseline. Linear mixed effects regression models were fit to assess change over time. Mean unprotected anal intercourse (UAI) episodes decreased significantly from baseline to acute postintervention (β=-4.86; 95% confidence interval [CI]=-7.48, -2.24; p=0.0015) and from baseline to 6 months postbaseline (β=-5.07; 95% CI=-7.85, -2.29; p=0.0017; test of fixed effects χ(2)=16.59; df=2,13; p=0.0002). On average, there was a significant decrease over time in the number of crystal methamphetamine episodes in the past 3 months (χ(2)=22.43; df=2,15; p<0.0001), and the number of days of crystal methamphetamine use in the past 30 days (χ(2)=9.21; df=2,15; p=0.010). Statistically significant reductions in depressive symptoms and poly-substance use were also maintained. Adding behavioral activation to risk reduction counseling for MSM with problematic crystal methamphetamine use may augment the potency of a risk reduction intervention for this population. Due to the small sample size and time intensive intervention, future testing in a randomized design is necessary to determine efficacy, with subsequent effectiveness testing.

Effects of nicotinic acetylcholine receptor agonists on cognition in rhesus monkeys with a chronic cocaine self-administration history

Cocaine use is associated with impaired cognitive function, which may negatively impact treatment outcomes. One pharmacological strategy to improve cognition involves nicotinic acetylcholine receptor (nAChR) stimulation. However, the effects of chronic cocaine exposure on nAChR distribution and function have not been characterized. Thus, one goal of this study was to examine nAChR availability in rhesus monkeys with an extensive cocaine self-administration history (n = 4; ~6 years, mean intake, 1463 mg/kg) compared to age-matched cocaine-naive control monkeys (n = 5). Using [¹¹C]-nicotine and positron emission tomography (PET) imaging, cocaine-experienced monkeys showed significantly higher receptor availability in the hippocampus compared to cocaine-naive monkeys. A second goal was to examine the effects of nAChR agonists on multiple domains of cognitive performance in these same monkeys. For these studies, working memory was assessed using a delayed match-to-sample (DMS) task, associative learning and behavioral flexibility using stimulus discrimination and reversal learning tasks. When administered acutely, the nonselective high-efficacy agonist nicotine, the low-efficacy α4β2* subtype-selective agonist varenicline and the high-efficacy α7 subtype-selective agonist, PNU-282987 significantly improved DMS performance in both cocaine-naive and cocaine-experienced monkeys. Individual doses of nicotine and varenicline that engendered maximum cognitive enhancing effects on working memory did not affect discrimination or reversal learning, while PNU-282987 disrupted reversal learning in the cocaine-naive monkeys. These findings indicate that a cocaine self-administration history influenced nAChR distribution and the effects of nAChR agonists on cognitive performance, including a reduced sensitivity to the disrupting effects on reversal learning. The cognitive enhancing effects of nAChR agonists may be beneficial in combination with behavioral treatments for cocaine addiction. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

Cocaine use in the past year is associated with altitude of residence

OBJECTIVES

Recently, increased rates of suicide in US counties at higher altitudes have been noted. Because of the documented association between cocaine use and suicide, we hypothesized that there would be a correlation between incidence of cocaine use and altitude of residence.

METHODS

Cocaine use data were obtained from the Substate Substance Abuse Estimates from the 1999-2001 National Surveys on Drug Use and Health. Data related to the percentages of people 12 years or older who used cocaine in the past year. Average elevation for US counties was calculated using the Shuttle Radar Topography Mission elevation data set, and subject region elevation was calculated by averaging the weighted elevations of each region's relevant counties. The correlation between elevation of a substate region and incidence of cocaine use in that region was calculated using Pearson correlation coefficients.

RESULTS

A significant correlation exists between mean altitude of a substate region and incidence of cocaine use in that region (r = 0.34; P < 0.0001). Regression analysis controlling for age, sex, race, education level, income, unemployment, and population density was performed. Altitude remained a significant factor (P = 0.007), whereas male sex (P = 0.008) and possessing less than a college education (P < 0.0001) were also significant predictors of self-reported cocaine use in the past year. It is important to note that cocaine use was assessed in isolation of other drugs of abuse, an additional confounding variable.

CONCLUSIONS

This study demonstrates a significant correlation between altitude of substate region of residence and incidence of cocaine use. It is possible that stress response due to hypoxia is responsible; however, this requires further investigation. However, because other substance use was not assessed, specificity of this association is unknown. In addition, this correlation may help explain the increased rate of suicide in areas of higher elevation.

Agonist replacement therapy for cocaine dependence: a translational review

Cocaine use disorders are prevalent throughout the world. Agonist replacement therapy is among the most effective strategies for managing substance use disorders including nicotine and opioid dependence. This paper reviews the translational literature, including preclinical experiments, human laboratory studies and clinical trials, to determine whether agonist-replacement therapy is a viable strategy for managing cocaine dependence. Discussion is limited to transporter blockers (i.e., methylphenidate) and releasers (i.e., amphetamine analogs) that are available for use in humans in the hope of impacting clinical research and practice more quickly. The translational review suggests that agonist-replacement therapy, especially monoamine releasers, may be effective for managing cocaine dependence. Future directions for medications development are also discussed because the viability of agonist-replacement therapy for cocaine dependence may hinge on identifying novel compounds or formulations that have less abuse and diversion potential.

Pharmacotherapeutics directed at deficiencies associated with cocaine dependence: focus on dopamine, norepinephrine and glutamate

Much effort has been devoted to research focused on pharmacotherapies for cocaine dependence yet there are no FDA-approved medications for this brain disease. Preclinical models have been essential to defining the central and peripheral effects produced by cocaine. Recent evidence suggests that cocaine exerts its reinforcing effects by acting on multiple neurotransmitter systems within mesocorticolimibic circuitry. Imaging studies in cocaine-dependent individuals have identified deficiencies in dopaminergic signaling primarily localized to corticolimbic areas. In addition to dysregulated striatal dopamine, norepinephrine and glutamate are also altered in cocaine dependence. In this review, we present these brain abnormalities as therapeutic targets for the treatment of cocaine dependence. We then survey promising medications that exert their therapeutic effects by presumably ameliorating these brain deficiencies. Correcting neurochemical deficits in cocaine-dependent individuals improves memory and impulse control, and reduces drug craving that may decrease cocaine use. We hypothesize that using medications aimed at reversing known neurochemical imbalances is likely to be more productive than current approaches. This view is also consistent with treatment paradigms used in neuropsychiatry and general medicine.

Rationale for Using Exercise in the Treatment of Stimulant Use Disorders

Novel approaches to the treatment of stimulant abuse and dependence are needed. Clinical data examining the use of exercise as a treatment for the abuse of nicotine, alcohol, and other substances suggest that exercise may be a beneficial treatment for stimulant abuse. In addition, exercise has been associated with improvements in many other health-related areas that may be adversely affected by stimulant use or its treatment, such as sleep disturbance, cognitive function, mood, weight, quality of life, and anhedonia. Neurobiological evidence provides plausible mechanisms by which exercise could positively affect treatment outcomes in stimulant abuse. The National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) CTN-0037 Stimulant Reduction Intervention using Dosed Exercise (STRIDE) study is a multisite randomized clinical trial that compares exercise to health education as potential treatments for stimulant abuse or dependence. If effective, exercise may provide an additional approach to the treatment of stimulant use disorders.

Stimulant reduction intervention using dosed exercise (STRIDE) - CTN 0037: study protocol for a randomized controlled trial

Background

There is a need for novel approaches to the treatment of stimulant abuse and dependence. Clinical data examining the use of exercise as a treatment for the abuse of nicotine, alcohol, and other substances suggest that exercise may be a beneficial treatment for stimulant abuse, with direct effects on decreased use and craving. In addition, exercise has the potential to improve other health domains that may be adversely affected by stimulant use or its treatment, such as sleep disturbance, cognitive function, mood, weight gain, quality of life, and anhedonia, since it has been shown to improve many of these domains in a number of other clinical disorders. Furthermore, neurobiological evidence provides plausible mechanisms by which exercise could positively affect treatment outcomes. The current manuscript presents the rationale, design considerations, and study design of the National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) CTN-0037 Stimulant Reduction Intervention using Dosed Exercise (STRIDE) study.

Methods/Design

STRIDE is a multisite randomized clinical trial that compares exercise to health education as potential treatments for stimulant abuse or dependence. This study will evaluate individuals diagnosed with stimulant abuse or dependence who are receiving treatment in a residential setting. Three hundred and thirty eligible and interested participants who provide informed consent will be randomized to one of two treatment arms: Vigorous Intensity High Dose Exercise Augmentation (DEI) or Health Education Intervention Augmentation (HEI). Both groups will receive TAU (i.e., usual care). The treatment arms are structured such that the quantity of visits is similar to allow for equivalent contact between groups. In both arms, participants will begin with supervised sessions 3 times per week during the 12-week acute phase of the study. Supervised sessions will be conducted as one-on-one (i.e., individual) sessions, although other participants may be exercising at the same time. Following the 12-week acute phase, participants will begin a 6-month continuation phase during which time they will attend one weekly supervised DEI or HEI session.

Clinical Trials Registry

ClinicalTrials.gov, NCT01141608

http://clinicaltrials.gov/ct2/show/NCT01141608?term=Stimulant+Reduction+Intervention+using+Dosed+Exercise&rank=1

Stimulant abuse: pharmacology, cocaine, methamphetamine, treatment, attempts at pharmacotherapy

The high prevalence of stimulant abuse and its harmful consequences make the screening, diagnosis, and referral for treatment of persons with stimulant abuse a top concern for primary care providers. Having a working knowledge of use patterns, clinical symptomatology, end-organ effects, and advances in treatment of stimulant abuse is essential. Although cocaine and amphetamine have different use patterns, duration of action, and so forth, the consequences of use are remarkably similar. Primary care is at the forefront of screening, brief risk reduction interventions, and diagnosis of medical sequelae, with referral to addiction specialist treatment when necessary.