Prediction of Treatment Outcome by Baseline Urine Cocaine Results and Self‐Reported Cocaine Use for Cocaine and Opioid Dependence

Exploring the mediating role of baseline urinalysis results on demographic characteristics and stimulant use disorder treatment outcomes

INTRODUCTION

Baseline stimulant urinalysis (UA) is one of the most reliable predictors of stimulant use disorder treatment outcomes. Yet we know little about the role of baseline stimulant UA mediating the effects of different baseline characteristics on treatment outcomes.

OBJECTIVES

This study aimed to explore the potential mediating role of baseline stimulant UA results on the relationship between baseline characteristics and total number of stimulant negative UAs submitted during treatment.

METHODS

The study team conducted analyses on data from a multisite randomized clinical trial of contingency management (CM) targeting stimulant use among individuals enrolled in methadone maintenance treatment programs (n = 394). Baseline characteristics included trial arm, education, race, sex, age, and Addiction Severity Index (ASI) composite measures. Baseline stimulant UA was the mediator and total number of stimulant negative UAs provided during treatment was the primary outcome variable.

RESULTS

The baseline characteristics of sex (OR = 1.85), ASI drug (OR = 0.01) and psychiatric (OR = 6.20) composites were directly associated with the baseline stimulant UA result (p < 0.05 for all). Baseline stimulant UA result (B = -8.24), trial arm (B = -2.55), ASI drug composite (B = -8.38) and education (B = -1.95) were directly associated with the total number of negative UAs submitted (p < 0.05 for all). The evaluation of indirect effects of baseline characteristics on the primary outcome through baseline stimulant UA revealed significant mediated effects for the ASI drug composite (B = -5.50) and age (B = -0.05; p < 0.05 for both).

CONCLUSIONS

Baseline stimulant UA is a strong predictor of stimulant use treatment outcomes and mediates the association of some baseline characteristics and a stimulant use treatment outcome.

Predictors of Retention and Drug Use Among Patients With Opioid Use Disorder Transferred to a Specialty "Second Chance" Methadone Program

Background

Many patients in methadone treatment have difficulty achieving or maintaining drug abstinence, and many clinics have policies that lead to discharging these patients. We designed a pilot "Second Chance" (SC) program for patients scheduled to be discharged from other local methadone clinics to be transferred to our clinic.

Aim

Determine whether SC patients' retention and opioid use is related to physical or mental health conditions, non-opioid substance use, or treatment features.

Methods

From December 2012 to December 2014, this program enrolled 70 patients who were discharged from other clinics in the area; we were their last remaining option for methadone treatment. Unlike the clinic's standard policies, the treatment focus for SC patients was retention rather than abstinence. This program focused on connection to care (eg, psychiatric services) and enabled patients to continue receiving services despite ongoing substance use. Each patient was assessed at treatment entry and followed until June 2016 to evaluate outcomes.

Results

SC patients receiving disability benefits (n = 37) vs. non-disabled (n = 33) had significantly (P < .05) higher rates of current DSM-IV Axis I psychiatric diagnosis (97% vs 70%), prescriptions for opioids (84% vs 55%) and benzodiazepines (65% vs 27%), and higher methadone doses at admission (58 vs 46 mg) but did not differ significantly in rates of 6-month or 1-year retention (77% and 56%, respectively) or all-drug use (39% positive urine drug screens). Methadone doses >65 mg predicted significantly longer retention and less opioid use, but these effects were not moderated by baseline characteristics.

Conclusions

Patients in methadone treatment struggling to achieve abstinence may benefit from retention-oriented harm-reduction programs. Higher methadone doses can improve retention and opioid abstinence despite psychiatric comorbidities. Further work is needed to improve program implementation and outcomes in this complex population.

A Retrospective Comparative Study in Patients With Cocaine Use Disorder Comorbid With Attention Deficit Hyperactivity Disorder Undergoing an rTMS Protocol Treatment

Background: Adult attention-deficit/hyperactivity disorder (ADHD) is associated with high comorbidity with other psychiatric diseases, including cocaine use disorder (CocUD). Given the common fronto-striatal dysfunction, ADHD patients often use cocaine as self-medication for ameliorating symptoms by increasing striatal dopamine release. Yet, comorbidity with ADHD is related to poor treatment outcomes. CocUD has been treated with transcranial magnetic stimulation (TMS), but no studies investigated the outcomes in patients comorbid with ADHD. Methods: Twenty-two ADHD/CocUD and 208 CocUD-only participants received a high-frequency (15 Hz) rTMS treatment stimulating the left-DLPFC. We investigated whether both groups of patients shared similar demographic and clinical characteristics at baseline. Then, we monitored the effect of treatment testing for potential differences between groups. Results: At baseline demographic, toxicology and clinical features were not different between the two groups except for global severity index (GSI from SCL-90): patients of ADHD/CocUD group reported higher general symptomatology compared to the CocUD-only group. Concerning the effect of treatment, both groups significantly improved over time regarding cocaine use, craving, and other negative affect symptoms. No differences were observed between groups. Conclusions: To our knowledge, this is the first study comparing the demographic characterization and rTMS clinical improvements of patients with a dual diagnosis of ADHD and CocUD against CocUD-only patients. Cocaine use and common self-reported withdrawal/abstinence symptoms appear to benefit from rTMS treatment with no differences between groups. Future studies are needed to further investigate these preliminary results.

"I's" on the prize: A systematic review of individual differences in Contingency Management treatment response

Contingency Management is an evidence-based treatment for substance use disorders with strong potential for measurement-based customization. Previous work has examined individual difference factors in Contingency Management treatment response of potential relevance to treatment targeting and adaptive implementation; however, a systematic review of such factors has not yet been conducted. Here, we summarize and evaluate the existing literature on patient-level predictors, mediators, and moderators of Contingency Management treatment response in stimulant and/or opioid using outpatients - clinical populations most frequently targeted in Contingency Management research and clinical practice. Our search strategy identified 648 unique, peer-reviewed publications, of which 39 met full inclusion criteria for the current review. These publications considered a variety of individual difference factors, including (1) motivation to change and substance use before and during treatment (8/39 publications), (2) substance use comorbidity and chronicity (8/39 publications), (3) psychiatric comorbidity and severity (8/39 publications), (4) medical, legal, and sociodemographic considerations (15/39 publications), and (5) cognitive-behavioral variables (1/39 publications). Contingency Management was generally associated with improved treatment outcomes (e.g., longer periods of continuous abstinence, better retention), regardless of individual difference factors; however, specific patient-level characteristics were associated with either an enhanced (e.g., more previous treatment attempts, history of sexual abuse, diagnosis of antisocial personality disorder) or diminished (e.g., complex post-traumatic stress symptoms, pretreatment benzodiazepine use) response to Contingency Management. Overall, the current literature is limited but existing evidence generally supports greater benefits of Contingency Management in patients who would otherwise have a poorer prognosis in standard outpatient care. It was also identified that the majority of previous work represents a posteriori analysis of pre-existing clinical samples and has therefore rarely considered pre-specified, hypothesis-driven individual difference factors. We therefore additionally highlight patient-level factors that are currently understudied, as well as promising future directions for measurement-based treatment adaptations that may directly respond to patient traits and states to improve Contingency Management effectiveness across individuals and over time.

Family Related Factors and Concurrent Heroin Use in Methadone Maintenance Treatment in China

BACKGROUND

The use of heroin during Methadone Maintenance Treatment (MMT) is a challenging problem that contributes to poor treatment outcomes. Families may play an important role in addressing concurrent heroin use during MMT, especially in collectivist societies such as China.

OBJECTIVES

In this study, we explored the relationship between family-related factors and concurrent heroin use during MMT in China.

METHODS

This study was conducted at 68 MMT clinics in five provinces of China. There were 2,446 MMT clients in the analysis. Demographic information, MMT dosage, family members' heroin use status, family support of MMT, family problem, and self-reported heroin use were collected in a cross-sectional survey. The most recent urinalysis of opiate use was obtained from clinical records.

RESULTS

Of the 2,446 participants, 533 (21.79%) self-reported heroin use in the previous seven days or had a positive urine morphine test result in the clinic record. Participants whose family member[s] used heroin were 1.59 times (95% CI: 1.17, 2.15) more likely to use concurrently during treatment. Those with family members who totally support them on the MMT were less likely to use (AOR: 0.75, 95% CI: 0.60, 0.94). Having more family problems was positively associated with concurrent heroin use (AOR: 2.01, 95% CI: 1.03, 3.93).

CONCLUSIONS

The results highlight the importance of the family's role in concurrent heroin use during MMT programs. The study's findings may have implications for family-based interventions that address concurrent heroin use.

Concurrent drug injection during opioid agonist treatment among people who inject drugs in Ukraine

Ongoing drug use during opioid agonist treatment (OAT) negatively affects treatment and health outcomes, and increases treatment dropout. This study aimed to examine correlates of concurrent illicit drug use among OAT patients in Ukraine. A random sample of 434 patients currently on OAT receiving buprenorphine (BMT) or methadone maintenance treatment (MMT) from five cities in Ukraine were assessed for factors associated with self-reported concurrent illicit drug use during OAT using a multivariable logistic regression. Among 434 OAT patients, 100 (23%) reported concurrent drug injecting in the previous 30 days; 28% of these were injecting ≥20 days. While 100 (100%) of these injected opioids, 24 (24%) injected stimulants; 40 (40%) met criteria for polysubstance use disorder that included opioids, stimulants and alcohol. Independent correlates of concurrent drug injection included: being on MMT vs. BMT (aOR = 2.8, 95%CI = 1.4-5.8), lower OAT dosage (aOR = 1.7, 95%CI = 1.1-2.7), more severe addiction severity (aOR = 2.3, 95%CI = 1.4-3.8), younger age of injection initiation (aOR = 2.3, 95%CI = 1.3-3.9), and presence of alcohol use disorder (aOR = 2.1, 95%CI = 1.3-3.5); participants living with parents were negatively associated with concurrent drug injection. Concurrent drug use was prevalent among OAT patients in Ukraine indicating the urgent needs for tailored interventions and changes in OAT program design and implementation. Results highlight the importance of prescribing an adequate OAT dosage, and discrepancies between MMT and BMT programs in Ukraine addressing needs of OAT patients with specific characteristics such as severe opioid and alcohol dependence.

The Impact of Early Substance Use Disorder Treatment Response on Treatment Outcomes Among Pregnant Women With Primary Opioid Use

OBJECTIVES

This study examined the impact of early patient response on treatment utilization and substance use among pregnant participants enrolled in substance use disorder (SUD) treatment.

METHODS

Treatment responders (TRs) and treatment nonresponders (TNRs) were compared on pretreatment and treatment measures. Regression models predicted treatment utilization and substance use.

RESULTS

TR participants attended more treatment and had lower rates of substance use relative to TNR participants. Regression models for treatment utilization and substance use were significant. Maternal estimated gestational age (EGA) and baseline cocaine use were negatively associated with treatment attendance. Medication-assisted treatment, early treatment response, and baseline SUD treatment were positively associated with treatment attendance. Maternal EGA was negatively associated with counseling attendance; early treatment response was positively associated with counseling attendance. Predictors of any substance use at 1 month were maternal education, EGA, early treatment nonresponse, and baseline cocaine use. The single predictor of any substance use at 2 months was early treatment nonresponse. Predictors of opioid use at 1 month were maternal education, EGA, early treatment nonresponse, and baseline SUD treatment. Predictors of opioid use at 2 months were early treatment nonresponse, and baseline cocaine and marijuana use. Predictors of cocaine use at 1 month were early treatment nonresponse, baseline cocaine use, and baseline SUD treatment. Predictors of cocaine use at 2 months were early treatment nonresponse and baseline cocaine use.

CONCLUSIONS

Early treatment response predicts more favorable maternal treatment utilization and substance use outcomes. Treatment providers should implement interventions to maximize patient early response to treatment.

Abstinence at Successful Discharge in Publicly Funded Addiction Health Services

Abstinence at successful discharge in substance use disorder treatment is important to reducing relapse rates and increasing long-term recovery from substance use disorders. However, few studies have examined abstinence as an essential component of successful discharge. This study examined rates and correlates of reported abstinence (nonuse of drugs 30 days prior to successful discharge) among clients attending publicly funded treatment in Los Angeles County, California. Finding show that only 36% of clients who were successfully discharged reported abstinence. Black clients were less likely than non-Hispanic Whites to report abstinence at successful discharge. Clients in methadone treatment programs were less likely than outpatient clients to report abstinence, whereas clients referred to treatment through the legal system (Proposition 36) were more likely to report abstinence compared to self-referred clients. Findings underscore the importance of systematic assessment of abstinence in determining successful discharge and provide a basis for further examination of strategies to improve abstinence and reduce relapse.

Continuous Abstinence During Early Alcohol Treatment is Significantly Associated with Positive Treatment Outcomes, Independent of Duration of Abstinence

AIMS

Neither the predictive value of early continuous abstinence in alcohol use disorder (AUD) or the point at which this effect may emerge has been evaluated. This analysis of the Combined Pharmacotherapies and Behavioral Interventions (COMBINE) clinical trial evaluated whether abstinence early in treatment was a predictor of longer term abstinence.

METHODS

Participants who stated a goal of total abstinence (N = 954) were dichotomized into Early Abstainer vs. Nonabstainers and were compared on a variety of drinking outcome measures that are frequently used in clinical trial evaluations of alcohol treatment strategies, as a function of duration of early continuous abstinence.

RESULTS

Significant differences existed for every outcome. Early Abstinence was significantly associated with fewer drinks per drinking day, number of drinking and number of heavy drinking days, and longer time to first drinking and first heavy drinking day. Effects were evident within the first week. The magnitude of all effects increased as the duration of early abstinence (1-4 weeks) increased, though the size of increase varied across the outcomes.

CONCLUSIONS

These data provide evidence that drinking at the beginning of alcohol treatment is significantly and robustly associated with drinking throughout and at the end of a clinical trial treatment for AUD. Early drinking may be a useful early index to identify whether patients are responding positively to a treatment strategy, and provides a useful method for tailoring treatment to patients that is consistent with a personalized medicine approach.

Modafinil in the treatment of crack-cocaine dependence in the Netherlands: Results of an open-label randomised controlled feasibility trial

BACKGROUND

Crack-cocaine dependence is a serious disorder with no approved pharmacological treatment. Modafinil is a promising medication with increased cocaine abstinence and reduced craving in some previous studies. In the present study, we examined the acceptance, safety and potential benefits of modafinil as an add-on treatment to cognitive behavioural therapy (CBT) in crack-cocaine dependent patients.

METHODS

Sixty-five crack-cocaine dependent outpatients participated in an open-label, randomised feasibility trial. Patients were randomised to receive either 12-week individual CBT plus 400 mg/day modafinil or 12-week individual CBT only. The primary outcome measure was CBT treatment retention. Secondary outcomes included modafinil adherence, tolerability and safety, use of cocaine and other substances, cocaine craving, health, social functioning and patient satisfaction.

RESULTS

Modafinil adherence was low, with only 10% treatment completers. Intent-to-treat analyses showed that modafinil did not improve CBT treatment retention or any of the secondary cocaine-related outcomes. Both groups showed similar, large reductions in cocaine use during the study treatment. Post hoc exploratory analyses within the CBT plus modafinil group showed significantly larger baseline to week 12 reductions in cocaine use days in high (⩾ 8 weeks) modafinil adherent patients.

CONCLUSIONS

Acceptance and benefits of modafinil were not demonstrated in the present study. Since reduction in cocaine use was observed in high modafinil adherent patients, further research in the treatment of cocaine dependence, in which modafinil adherence is optimised, is warranted.

Implementation of integrated therapies for comorbid post-traumatic stress disorder and substance use disorders in community substance abuse treatment programs

ISSUES

The high prevalence of trauma and post-traumatic stress disorder (PTSD) in individuals with substance use disorders (SUDs) presents a number of treatment challenges for community treatment providers and programs in the USA. Although several evidence-based, integrated therapies for the treatment of comorbid PTSD/SUD have been developed, rates of utilisation of such practices remain low in community treatment programs.

APPROACH

The goal of this article was to review the extant literature on common barriers that prevent adoption and implementation of integrated treatments for PTSD/SUD among substance abuse community treatment programs.

KEY FINDINGS

Organisational, provider-level and patient-level factors that drive practice decisions were discussed, including organisational philosophy of care policies, funding and resources, as well as provider and patient knowledge and attitudes related to implementation of new integrated treatments for comorbid PTSD and SUD.

IMPLICATIONS AND CONCLUSIONS

Understanding and addressing these community treatment challenges may facilitate use of evidence-based integrated treatments for comorbid PTSD and SUD.

Initial abstinence status and contingency management treatment outcomes: does race matter?

OBJECTIVE

Limited research has evaluated African American substance users' response to evidence-based treatments. This study examined the efficacy of contingency management (CM) in African American and White cocaine users.

METHOD

A secondary analysis evaluated effects of race, treatment condition, and baseline cocaine urine sample results on treatment outcomes of African American (n = 444) and White (n = 403) cocaine abusers participating in one of six randomized clinical trials comparing CM to standard care.

RESULTS

African American and White patients who initiated treatment with a cocaine-negative urine sample remained in treatment for similar durations and submitted a comparable proportion of negative samples during treatment regardless of treatment type; CM was efficacious in both races in terms of engendering longer durations of abstinence in patients who began treatment abstinent. Whites who began treatment with a cocaine positive sample remained in treatment longer and submitted a higher proportion of negative samples when assigned to CM than standard care. African Americans who initiated treatment with a cocaine positive sample, however, did not remain in treatment longer with CM compared with standard care, and gains in terms of drug use outcomes were muted in nature relative to Whites. This interaction effect persisted through the 9-month follow-up period.

CONCLUSIONS

CM is not equally effective in reducing drug use among all subgroups, specifically African American patients who are using cocaine upon treatment entry. Future research on improving treatment outcomes in this population is needed.

Prevalence of traumatic brain injury in cocaine-dependent research volunteers

BACKGROUND

There is a high prevalence of traumatic brain injury (TBI) among those with substance dependence. However, TBI often remains undiagnosed in these individuals, due to lack of routine screening in substance use treatment settings or due to overlap in some of the cognitive sequelae (eg impulsivity, disinhibition) of TBI and cocaine dependence.

METHODS

The prevalence of self-reported mild to moderate TBI in a group of cocaine-dependent (n = 95) and a group of healthy volunteers (n = 75) enrolled at the same facility was assessed. Additionally, the relationship between TBI and clinically relevant correlates, including impulsivity, cocaine use history, and treatment outcome in the cocaine-dependent group was also examined.

RESULTS

A higher proportion of individuals with cocaine dependence (29.5%) reported having suffered a TBI in their lifetime compared to controls (8%) on a Closed Head Injury scale. Among cocaine users, the average age of sustaining TBI was significantly lower than the age of initiating cocaine use. Presence of TBI was not associated with higher impulsivity on the Barratt Impulsiveness Scale-11 or self-reported years of cocaine use. No differences were noted on treatment outcome for cocaine dependence as measured by treatment effectiveness scores (TES) between cocaine users with TBI and their non-TBI counterparts.

CONCLUSIONS

These results are the first to highlight the high prevalence of TBI among individuals with cocaine dependence. This study underscores the possible role of TBI history as a risk factor for onset of cocaine use, however, more research is needed to determine the impact of co-morbid TBI as a complicating factor in the substance abuse treatment setting.

Gender-specific predictors of retention and opioid abstinence during methadone maintenance treatment

AIMS

Retention in methadone maintenance treatment (MMT) for 1 year is associated with positive outcomes including opioid abstinence, however, most studies have not investigated gender differences. We hypothesized that predictors of retention and opioid abstinence would differ between men and women, and aimed to determine which factors best predict retention and abstinence for each gender.

METHODS

Data were available for 290 patients (173 M, 117 F) admitted to outpatient MMT. Regression analyses, stratified by gender, were conducted to identify unique predictors of MMT retention (<1 vs. >1 year) and opioid abstinence rate (proportion of opioid-free urine samples up to 1 year retention).

RESULTS

Gender did not significantly predict treatment retention (mean = 231 days, 39% retained > 1 year) or opioid abstinence (49% overall). For males, significant predictors of > 1-year retention were urine samples negative for opioids (odds ratio [OR] = 6.67) and cannabinoids (OR = 5.00) during the first month, and not cocaine dependent (OR = 2.70). Significant predictors of higher long-term opioid abstinence were first-month urine samples negative for opioids and cocaine metabolites. For females, significant predictors of >1-year retention were first-month urine samples negative for cocaine metabolites (OR = 4.00) and cannabinoids (OR = 9.26), and no history of sexual victimization (OR = 3.03). The only significant predictor of higher opioid abstinence rate was first-month opioid-free urine samples.

CONCLUSIONS

These findings indicate gender-specific predictors of MMT retention and opioid abstinence. Future studies on MMT outcomes should examine each gender separately, and consider unique pathways by which females and males adhere to, and benefit from MMT.

The impact of recent cocaine use on plasma levels of methadone and buprenorphine in patients with and without HIV-infection

Cocaine decreases methadone and buprenorphine plasma concentrations. HIV infection and/or antiretroviral medication use may impact these relationships. We sought to determine the association between recent cocaine use and methadone and buprenorphine concentrations in HIV-infected and uninfected subjects in clinical care. R- and S-methadone or buprenorphine and norbuprenorphine concentrations were assessed at 0.5, 1, 2, and 24 hours after dosing in subjects with confirmed cocaine use and abstinence. We compared methadone and buprenorphine concentrations for cocaine use vs. abstinence, by HIV status in 16 subjects receiving methadone (6 HIV-infected) and 17 receiving buprenorphine (8 HIV-infected). With recent cocaine use, peak R-methadone (244 vs. 297 ng/mL, p = 0.03) and peak S-methadone (285 vs. 339 ng/mL); p = 0.03 concentrations were lower in HIV-uninfected subjects only. Peak buprenorphine and norbuprenorphine concentrations were unchanged regardless of cocaine use or HIV status. Cocaine may decrease methadone concentrations in HIV-uninfected subjects. HIV infection or its treatment may attenuate cocaine's effect on methadone.

Changes in dopamine transporter binding in nucleus accumbens following chronic self-administration cocaine: heroin combinations

Concurrent use of cocaine and heroin (speedball) has been shown to exert synergistic effects on dopamine neurotransmission in the nucleus accumbens (NAc), as observed by significant increases in extracellular dopamine levels and compensatory elevations in the maximal reuptake rate of dopamine. The present studies were undertaken to determine whether chronic self-administration of cocaine, heroin or a combination of cocaine:heroin led to compensatory changes in the abundance and/or affinity of high- and low-affinity DAT binding sites. Saturation binding of the cocaine analog [(125) I] 3β-(4-iodophenyl)tropan-2β-carboxylic acid methyl ester ([(125) I]RTI-55) in rat NAc membranes resulted in binding curves that were best fit to two-site binding models, allowing calculation of dissociation constant (Kd ) and binding density (Bmax ) values corresponding to high- and low-affinity DAT binding sites. Scatchard analysis of the saturation binding curves clearly demonstrate the presence of high- and low- affinity binding sites in the NAc, with low-affinity sites comprising 85 to 94% of the binding sites. DAT binding analyses revealed that self-administration of cocaine and a cocaine:heroin combination increased the affinity of the low-affinity site for the cocaine congener RTI-55 compared to saline. These results indicate that the alterations observed following chronic speedball self-administration are likely due to the cocaine component alone; thus further studies are necessary to elaborate upon the synergistic effect of cocaine:heroin combinations on the dopamine system in the NAc.

Treatment of crack-cocaine dependence with topiramate: a randomized controlled feasibility trial in The Netherlands

BACKGROUND

Crack-cocaine dependence is a complex disorder with limited treatment options. Topiramate is one of the promising medications with reported reductions in cocaine use and craving in former studies. The present study evaluated the acceptance and effectiveness of topiramate as an add-on to cognitive behavioral therapy (CBT) in crack-cocaine dependent patients.

METHODS

Seventy-four crack-cocaine dependent outpatients participated in an open-label, randomized feasibility trial. They were randomized to receive either 12-week CBT plus topiramate (200mg/day) or 12-week CBT only. The primary outcome measure was treatment retention. Secondary outcomes included medication adherence, safety, cocaine and other substance use, health, social functioning, and patient satisfaction.

RESULTS

Adherence to topiramate treatment was low. In the intent-to-treat analyses, topiramate neither improved treatment retention nor reduced cocaine and other substance use. Post hoc, exploratory analyses suggested a moderation effect of comorbid opioid dependence, with a significant effect of topiramate on cocaine use reduction only in crack-cocaine dependent patients with comorbid opioid dependence.

CONCLUSIONS

Topiramate was safe and well-tolerated in this sample of crack-cocaine dependent patients, but efficacy was not supported probably due to low acceptance of the treatment. Given the equivocal results of previous studies and the negative findings in our study, the potential of topiramate in the treatment of cocaine dependence seems limited.

Clinically relevant characteristics associated with early treatment drug use versus abstinence

Background

This study describes early treatment drug use status and associated clinical characteristics in a diverse sample of patients entering outpatient substance abuse psychosocial counseling treatment. The goal is to more fully characterize those entering treatment with and without active use of their primary drug in order to better understand associated treatment needs and resilience factors.

Methods

We examined baseline data from a NIDA Clinical Trials Network (CTN) study (Web-delivery of Treatment for Substance Use) with an all-comers sample of patients (N = 494) entering 10 outpatient treatment centers. Patients were categorized according to self-identified primary drug of abuse (alcohol, cocaine/stimulants, opioids, marijuana) and by baseline drug use status (positive/negative) based on urine testing or self-reports of recent use (alcohol). Characteristics were examined by primary drug and early use status.

Results

Classified as drug-negative were 84%, 76%, 62%, and 33% of primary opioid, stimulant, alcohol, and marijuana users; respectively. Drug-positive versus -negative patients did not differ on demographics or rates of substance abuse/dependence diagnoses. However, those negative for active use had better physical and mental health profiles, were less likely to be using a secondary drug, and were more likely to be attending 12-step self-help meetings.

Conclusions

Early treatment drug abstinence is common among substance users entering outpatient psychosocial counseling programs, regardless of primary abused drug. Abstinence (by negative UA) is associated with better health and mental health profiles, less secondary drug use, and more days of 12-step attendance. These data highlight differential treatment needs and resiliencies associated with early treatment drug use status.

Trial registration

NCT01104805.

Older methadone patients achieve greater durations of cocaine abstinence with contingency management than younger patients

BACKGROUND AND OBJECTIVES

Contingency management (CM) interventions are efficacious in treating cocaine abusing methadone patients, but few studies have examined the effect of age on treatment outcomes in this population. This study evaluated the impact of age on treatment outcomes in cocaine abusing methadone patients.

METHODS

Data were analyzed from 189 patients enrolled in one of three randomized studies that evaluated the efficacy of CM versus standard care (SC) treatment.

RESULTS

Age was associated with some demographics and drug use characteristics including racial composition, education, and methadone dose. Primary drug abuse treatment outcomes did not vary across age groups, but CM had a greater benefit for engendering longer durations of abstinence in the middle/older and older age groups compared to the younger age groups. At the 6-month follow-up, submission of a cocaine positive urine sample was predicted by submission of a cocaine positive sample at intake, higher methadone doses, and assignment to SC rather than CM treatment.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

As substance abusers are living longer, examination of the efficacy of pharmacological and psychosocial treatments specifically within older age groups may lead to a better understanding of subpopulations for whom enhanced treatments such as CM are warranted.

Wavelet-transformed temporal cerebral blood flow signals during attempted inhibition of cue-induced cocaine craving distinguish prognostic phenotypes

BACKGROUND

Cocaine addicted patients with positive cocaine urine status at treatment entry are far less likely to have a successful treatment outcome. This work aims to identify brain substrates that can distinguish this group of patients from their cocaine-negative counterparts in order to better understand this clinical phenotype. Going a step beyond conventional functional connectivity, we used wavelet transform coherence (WTC) to determine in which ways the temporal pattern of fMRI cerebral blood flow (CBF) signals during attempted inhibition of cue-induced cocaine craving may differ between these two groups.

METHODS

Using a critical node in motivational circuitry, amygdala, as a seed, whole brain correlations for the entire sample revealed a functional connection with the dorsal cingulate. Next, WTC maps of CBF were constructed for each individual, characterizing the temporal patterns between these two regions during craving inhibition.

RESULTS

As revealed by WTC, during attempted craving inhibition, the cocaine-negative subjects had significantly stronger and longer negative coherence between the amygdala and the dorsal cingulate, as compared to the cocaine-positive subjects. This relationship was neither evident in the resting state nor between two regions unrelated to inhibition processes.

CONCLUSIONS

The duration and strength of negative coherence calculated from wavelet-transformed CBF provide an objective and well-defined way to characterize brain responses during attempted inhibition of cue-induced craving, at the level of the individual. The stronger and sustained negative coherence in CBF between motivational (amygdala) and modulatory (dorsal cingulate) regions in cocaine-negative subjects may be a critical brain strength that fosters improved craving inhibition and thus, better clinical outcome.

Initiation of abstinence in adolescents treated for marijuana use disorders

This study assessed the time to initiation of marijuana abstinence in an adolescent treatment-seeking sample, and identified variables that were predictive of abstinence. Adolescents (N=69), ages 14 to 18 were randomly assigned to one of two 14-week behavioral treatments. Abstinence was measured with twice-weekly urine toxicology plus teen and parent reports. Discrete-time survival and hazard functions were conducted. The majority of adolescents achieved at least 1 week of abstinence, and 51% achieved 6 weeks of abstinence. Initiation of abstinence occurred by the sixth treatment week for 94% of teens with any abstinence suggesting that alternative, clinical approaches should be considered for those not responding by week 6. Teens with a drug negative urinalysis at intake, and teens that had two parents participating in treatment were more likely to achieve at least 6 weeks of abstinence. These findings, if replicated, can be used to inform clinical and research strategies that might lead to enhanced treatment efficacy and cost effectiveness for substance abuse treatment programming.

Treatment of cocaine withdrawal anxiety with guanfacine: relationships to cocaine intake and reinstatement of cocaine seeking in rats

RATIONALE

Successful treatment of cocaine addiction is severely impeded by the propensity of users to relapse. Withdrawal severity may serve as a key predictor of susceptibility to relapse. Therefore, the identification and treatment of cocaine withdrawal symptoms such as anxiety may improve addiction treatment outcome.

OBJECTIVES

The current study examined the role of anxiety-like behavior during cocaine withdrawal and anxiolytic treatment in reinstatement of cocaine seeking in an animal model of relapse.

METHODS

Male rats experienced daily IV cocaine self-administration. One group of animals received the norepinephrine α-2 agonist, guanfacine, or vehicle prior to anxiety testing 48 h after the last self-administration session. In the second group of rats, relationships between cocaine intake, anxiety-like behavior after withdrawal of cocaine, and reinstatement responding were investigated. The third and fourth groups of animals received guanfacine, yohimbine (norepinephrine α-2 antagonist), or vehicle once per day for 3 days 48 h after cessation of cocaine self-administration, followed by extinction and subsequent reinstatement induced by cocaine injections, cocaine-paired cues, and yohimbine administration.

RESULTS

Cocaine-withdrawn rats at 48 h demonstrated higher levels of anxiety-like behavior as measured on a defensive burying task when compared to yoked saline controls, an effect reversed by guanfacine treatment. Cocaine intake was positively correlated with measures of anxiety-like behavior during early withdrawal, and this anxiety-like behavior was significantly correlated with subsequent cocaine-primed reinstatement. Yohimbine treatment during early withdrawal increased reinstatement to conditioned cues, while guanfacine treatment reduced reinstatement to yohimbine.

CONCLUSIONS

These studies suggest an important role for noradrenergic mediation of anxiety-like behavior that emerges after withdrawal of cocaine and potential risk of relapse as modeled by reinstatement, and suggest that treatment of anxiety symptoms during early abstinence may reduce the risk of relapse.

Concurrent heroin use among methadone maintenance clients in China

BACKGROUND

The study examined concurrent illicit heroin use among methadone maintenance clients in China and its association with clients' demographic characteristics, treatment experience, and personal social network.

METHODS

Face-to-face surveys were conducted with 178 clients randomly recruited from six methadone maintenance treatment (MMT) clinics in Sichuan, China. Concurrent heroin use was measured based on self-report of heroin use during the past 30 days and a confirmatory urine morphine test. The participants' demographic characteristics and treatment factors were measured and examined. The drug use status of their family members and friends was also assessed.

RESULTS

A total of 80 participants (44.9%) who either reported illicit heroin use in the past 30 days or had a positive urine test were defined as using heroin concurrently. Having drug-using friends was significantly associated with increased concurrent heroin use. Longer length of treatment (2 years or longer) was associated with increased concurrent heroin use. Among those who had both drug-using family members and friends, more women (71.4%) than men (50.0%) used heroin. For those who had no drug-using family members or friends, more men (34.8%) than women (20.8%) used heroin.

DISCUSSION

Study findings indicate an urgent need to address concurrent illicit heroin use among MMT clients. Further examination of the influence of social networks on concurrent drug abuse behavior is encouraged. Results also highlight the importance of understanding gender differences in treatment seeking and behavioral changes, which is crucial to the development of gender-specific treatment strategies.

Antidepressants for cocaine dependence and problematic cocaine use

BACKGROUND

Cocaine dependence is a disorder for which no pharmacological treatment of proven efficacy exists, advances in the neurobiology could guide future medication development.

OBJECTIVES

To investigate the efficacy and acceptability of antidepressants alone or in combination with any psychosocial intervention for the treatment of cocaine dependence and problematic cocaine use.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE and CINAHL in July 2011 and researchers for unpublished trials.

SELECTION CRITERIA

Randomised clinical trials comparing antidepressants alone or associated with psychosocial intervention with placebo, no treatment, other pharmacological or psychosocial interventions.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

37 studies were included in the review (3551 participants).Antidepressants versus placebo: results for dropouts did not show evidence of difference, 31 studies, 2819 participants, RR 1.03 (Cl 95% 0.93 to 1.14). Looking at Abstinence from cocaine use, even though not statistically significant, the difference shown by the analysis in the three-weeks abstinence rate was in favour of antidepressants (eight studies, 942 participants, RR 1.22 (Cl 95% 0.99 to 1.51)). Considering only studies involving tricyclics, five studies, 367 participants, or only desipramine, four studies, 254 participants, the evidence was in favour of antidepressants. However, selecting only studies with operationally defined diagnostic criteria, statistical significance favouring antidepressants, as well as the trend for significance shown by the full sample, disappeared. Looking at safety issues, the results did not show evidence of differences (number of patients withdrawn for medical reasons, thirteen studies, 1396 participants, RR 1.39 (Cl 95% 0.91 to 2.12)). Subgroup analysis considering length of the trial, associated opioid dependence or associated psychosocial interventions as confounding factors, failed in showing consistent and statistically significant differences in favour of antidepressants.Antidepressants versus other drugs: Comparing antidepressants with dopamine agonists or with anticonvulsants, no evidence of differences was shown on dropouts and on other outcomes (abstinence from cocaine use, adverse events).

AUTHORS' CONCLUSIONS

At the current stage of evidence data do not support the efficacy of antidepressants in the treatment of cocaine abuse/dependence. Partially positive results obtained on secondary outcome measures, such as depression severity, do not seem to be associated with an effect on direct indicators of cocaine abuse/dependence. Antidepressants cannot be considered a mainstay of treatment for unselected cocaine abusers/dependents.

The impact of cocaine use on outcomes in HIV-infected patients receiving buprenorphine/naloxone

BACKGROUND

Cocaine use is common in opioid-dependent HIV-infected patients, but its impact on treatment outcomes in these patients receiving buprenorphine/naloxone is not known.

METHODS

We conducted a prospective study in 299 patients receiving buprenorphine/naloxone who provided baseline cocaine data and a subset of 266 patients who remained in treatment for greater than or equal to one quarter. Assessments were conducted at baseline and quarterly for 1 year. We evaluated the association between baseline and in-treatment cocaine use on buprenorphine/naloxone retention, illicit opioid use, antiretroviral adherence, CD4 counts, HIV RNA, and risk behaviors.

RESULTS

Sixty-six percent (197 of 299) of patients reported baseline cocaine use and 65% (173 of 266) of patients with follow-up data reported in-treatment cocaine use. Baseline and in-treatment cocaine use did not impact buprenorphine/naloxone retention, antiretroviral adherence, CD4 lymphocytes, or HIV risk behaviors. However, baseline cocaine use was associated with a 14.8 (95% confidence interval [CI], 9.0-24.2) times greater likelihood of subsequent cocaine use (95% CI, 9.0-24.2), a 1.4 (95% CI, 1.02-2.00) times greater likelihood of subsequent opioid use, and higher log10 HIV RNA (P < 0.016) over time. In-treatment cocaine use was associated with a 1.4 (95% CI, 1.01-2.00) times greater likelihood of concurrent opioid use.

CONCLUSIONS

Given cocaine use negatively impacts opioid and HIV treatment outcomes, interventions to address cocaine use in HIV-infected patients receiving buprenorphine/naloxone treatment are warranted.

Sustained release d-amphetamine reduces cocaine but not 'speedball'-seeking in buprenorphine-maintained volunteers: a test of dual-agonist pharmacotherapy for cocaine/heroin polydrug abusers

The aim of this study was to determine whether oral sustained release d-amphetamine (SR-AMP) reduces cocaine and opioid/cocaine combination ('speedball'-like) seeking in volunteers with current opioid dependence and cocaine dependence. Following outpatient buprenorphine (BUP) 8 mg/day stabilization without SR-AMP, eight participants completed a 3-week in-patient study with continued BUP 8 mg/day maintenance and double-blind ascending SR-AMP weekly doses of 0, 30, and 60 mg/day, respectively. After 3 days (Saturday-Monday) stabilization at each SR-AMP weekly dose (0, 15, or 30 mg administered at 0700 and 1225 each day), on Tuesday-Friday mornings (0900-1200 hours), participants sampled four drug combinations in randomized, counterbalanced order under double-blind, double-dummy (intranasal cocaine and intramuscular hydromorphone) conditions: cocaine (COC 100 mg+saline); hydromorphone (COC 4 mg+HYD 24 mg); 'speedball' (COC 100 mg+HYD 24 mg); and placebo (COC 4 mg+saline). Subjective and physiological effects of these drug combinations were measured. From 1230 to 1530 hours, participants could respond on a choice, 12-trial progressive ratio schedule to earn drug units (1/12th of total morning dose) or money units (US$2). SR-AMP significantly reduced COC, but not HYD or speedball, choices and breakpoints. SR-AMP also significantly reduced COC subjective (eg, abuse-related) effects and did not potentiate COC-induced cardiovascular responses. This study shows the ability of SR-AMP to attenuate COC self-administration, as well as its selectivity, in cocaine/heroin polydrug abusers. Further research is warranted to ascertain whether SR-AMP combined with BUP could be a useful dual-agonist pharmacotherapy.

Contingency management for cocaine use in methadone maintenance patients: when does abstinence happen?

Contingency management (CM) is an efficacious intervention for cocaine abusing methadone patients, but typically only about half of patients respond. By investigating time to onset of cocaine abstinence and factors associated with abstinence, we may be able to more efficiently direct CM approaches to patients most likely to benefit. Onset of cocaine abstinence was evaluated in cocaine abusing methadone maintenance patients (N = 193) enrolled in one of three randomized clinical trials of CM. Participants received standard treatment with frequent urine toxicology monitoring or standard treatment plus CM during the trials. Slightly more than half the sample obtained at least 1 week of cocaine abstinence, and approximately a third of the sample obtained at least 4 weeks of cocaine abstinence. Discrete-time survival and hazard analyses found Weeks 1 and 2 of the intervention period had the greatest probability for the initiation of abstinence, and few participants initiated any period of abstinence after Week 4. Patients randomized to CM, those with more years of cocaine use, and those with less recent cocaine use were more likely to achieve abstinence. Overall, these results indicate onset of cocaine abstinence is likely to occur early in treatment and in individuals with less severe cocaine use. Practical implications of these results for designing and implementing CM interventions in methadone maintenance clinics are discussed.

Motivational incentives research in the National Drug Abuse Treatment Clinical Trials Network

The purpose of this article is to review both main findings and secondary analyses from studies of abstinence incentives conducted in the National Drug Abuse Treatment Clinical Trials Network (CTN). Previous research has supported the efficacy of tangible incentives provided contingent on evidence of recent drug abstinence. CTN conducted the first multisite effectiveness trial of this novel intervention. Study participants were stimulant abusers (N = 803) participating in treatment at 14 clinical sites and randomly assigned to treatment as usual with or without a prize draw incentive program. Study participants could earn up to $400 over 3 months for submission of drug-free urine and breath (BAL) specimens. Three-month retention was significantly improved by incentives offered to psychosocial counseling clients (50% incentive vs. 35% control retained), whereas ongoing stimulant drug use was significantly reduced in methadone maintenance clients (54.4% incentive vs. 38.7% control samples testing stimulant-negative). In both settings, duration of continuous abstinence achieved was improved in the incentive condition. These studies support effectiveness of one abstinence incentive intervention and highlight the different outcomes that can be expected with application in methadone maintenance versus psychosocial counseling treatment settings. Secondary analyses have shown the importance of early treatment positive versus negative urine screens in moderating the outcome of abstinence incentives and have explored both safety and cost-effectiveness of the intervention. Implications for the use of motivational incentive methods in clinical practice are discussed.

The association between cocaine use and treatment outcomes in patients receiving office-based buprenorphine/naloxone for the treatment of opioid dependence

Cocaine use in patients receiving methadone is associated with worse treatment outcomes. The association between cocaine use and office-based buprenorphine/naloxone treatment outcomes is not known. We evaluated the association between baseline and in-treatment cocaine use, treatment retention, and urine toxicology results in 162 patients enrolled in a 24-week trial of primary care office-based buprenorphine/naloxone maintenance. Patients with baseline cocaine metabolite-negative urine toxicology tests compared with those with cocaine metabolite-positive tests had more mean weeks of treatment retention (18.3 vs. 15.8, p = .04), a greater percentage completed 24 weeks of treatment (50% vs. 33%, p = .04) and had a greater percentage of opioid-negative urines (47% vs. 34%, p = .02). Patients with in-treatment cocaine metabolite-negative urine toxicology tests compared with cocaine metabolite-positive patients had more mean weeks of treatment retention (19.0 vs. 16.5, p = .003), a greater percentage completed 24 weeks of treatment (60% vs. 30%, p < .001), and had a greater percentage of opioid-negative urines (51% vs. 35%, p = .001). We conclude that both baseline and in-treatment cocaine use is associated with worse treatment outcomes in patients receiving office-based buprenorphine/naloxone and may benefit from targeted interventions.

Behavioral economic analysis of opioid consumption in heroin-dependent individuals: effects of alternative reinforcer magnitude and post-session drug supply

This study investigated the extent to which hydromorphone (HYD) choice and behavioral economic demand were influenced by HYD unit price (UP), alternative money reinforcement magnitude and post-session HYD supply. Heroin-dependent research volunteers (n=13) stabilized on buprenorphine 8 mg/day first sampled two HYD doses (12 and 24 mg IM, labeled Drug A [session 1] and Drug B [session 2]). In each of the final six sessions, volunteers were given access to a 12-trial choice progressive ratio (PR) task and could earn a HYD unit dose (2 mg, fixed) or money ($2 or $4, varied across sessions), administered immediately after the work session. Before the PR task, volunteers were told which HYD supplemental dose (none, Drug A or B) would be available 3h after receiving the PR-contingent dose. PR-contingent HYD choice significantly decreased when $4 relative to $2 was concurrently available. Information about the post-session HYD supplement moderated this effect: when subjects were told a supplemental dose was available, HYD-seeking behavior decreased when the money alternative was smaller ($2), but this information did not further attenuate HYD choice, which was already low, when the money alternative was higher ($4). HYD demand elasticity was only increased by the $4 relative to $2 alternative without the HYD supplement. In summary, opioid-seeking behavior is influenced by the availability of concurrent non-drug and drug alternatives. These findings show that drug availability and non-drug alternatives interact to modulate drug-seeking behavior.

Treatment Outcome Predictors for Cocaine Dependence

Over the past decade, a large number of potential medications have been examined in clinical trials for cocaine dependence. Unfortunately, no effective pharmacotherapies for cocaine dependence have been found to date. Although effective treatments for cocaine dependence are still being investigated, a few variables have been found to significantly predict cocaine treatment response. These variables include cocaine use variables, such as days of cocaine use in the month before treatment, baseline urine cocaine results, and cocaine withdrawal symptoms. Comorbid depression and alcohol use have also been shown to be risk factors for relapse. Among personality variables, impulsivity and similar personality traits may predict treatment response. Initial promising findings with genetic polymorphism, brain activation, and stress response have also been found and need to be replicated in future studies.

Cocaine Withdrawal Symptoms Predict Medication Response in Cocaine Users

The purpose of this study was to examine the influence of cocaine withdrawal symptoms on addiction severity and treatment outcomes in methadone stabilized cocaine users who participated in pharmacotherapy trials using gamma-aminobutyric acid (GABA) medications. Subjects who fulfilled DSM-IV cocaine withdrawal criteria (n = 45), compared to those who did not (n = 40), showed a greater increase in cocaine free urines in response to pharmacotherapy with GABA medications. Altogether, our results and previous studies support the clinical utility of cocaine withdrawal symptoms in predicting treatment response to medications, such that low withdrawal severity may predict better treatment response to GABA medications, while high withdrawal severity may predict better response to adrenergic blockers. This hypothesis needs to be tested in prospective clinical trials.

Correlates of stimulant treatment outcome across treatment modalities

OBJECTIVE

This study evaluated variables associated with stimulant use outcomes in stimulant users (N = 800) receiving care in community outpatient psychosocial or methadone maintenance treatment clinics as part of a national multi-site clinical trial.

METHODS

Results from the full sample were examined first, and then predictors were examined separately in the two treatment modalities.

RESULTS

A cocaine-positive urine sample at study intake was the most robust and consistent correlate of stimulant use outcome in all analyses. Psychiatric distress, social environment and employment had differential effects on outcome across modalities.

CONCLUSIONS/SIGNIFICANCE

This study confirms that intake assessments have considerable value in identifying problems to be addressed in treatment.

The role of impulsive behavior in drug abuse

BACKGROUND

Impulsivity is a multifaceted construct that has recently been recognized as a factor contributing to enhanced vulnerability to drug abuse.

OBJECTIVES

In the present review, we focus on two facets of impulsivity (and tasks that measure them): (1) impulsive choice (delay discounting task) and (2) inhibitory failure (go/no-go, stop signal reaction time, and five-choice serial reaction time tasks). We also describe how performance on each of these tasks is associated with drug-related behavior during phases of drug abuse that capture the essential features of addiction (acquisition, escalation, and reinstatement of drug-seeking after drug access has terminated). Three hypotheses (H) regarding the relationship between impulsivity and drug abuse are discussed: (1) increased levels of impulsivity lead to drug abuse (H1), (2) drugs of abuse increase impulsivity (H2), and (3) impulsivity and drug abuse are associated through a common third factor (H3).

CONCLUSION

Impulsivity expressed as impulsive choice or inhibitory failure plays a role in several key transition phases of drug abuse. There is evidence to support all three nonexclusive hypotheses. Increased levels of impulsivity lead to acquisition of drug abuse (H1) and subsequent escalation or dysregulation of drug intake. Drugs of abuse may increase impulsivity (H2), which is an additional contributor to escalation/dysregulation. Abstinence, relapse, and treatment may be influenced by both H1 and H2. In addition, there is a relationship between impulsivity and other drug abuse vulnerability factors, such as sex, hormonal status, reactivity to nondrug rewards, and early environmental experiences that may impact drug intake during all phases of addiction (H3). Relating drug abuse and impulsivity in phases of addiction via these three hypotheses provides a heuristic model from which future experimental questions can be addressed.

Behavioral counseling content for optimizing the use of buprenorphine for treatment of opioid dependence in community-based settings: a review of the empirical evidence

There is growing empirical evidence of buprenorphine's effectiveness in treating opioid dependence in community-based settings in the U.S. Decades of research indicates that in order for buprenorphine to have a sizable effect, it must be appropriately supported by behavioral counseling. Studies to date have not established the optimal behavioral counseling content for supporting buprenorphine treatment. The objective of this article is: 1) to review evidence of the key treatment-relevant issues posed by opioid-dependent patients in community-based settings in the U.S.; and 2) to review behavioral counseling content that may optimize the use of buprenorphine for treating opioid dependence in such settings. Evidence points toward the use of behavioral counseling aimed at enhancing patients' motivation during treatment entry followed by an emphasis on improving coping/relapse prevention skills during the primary phase of treatment.

A perfect platform: combining contingency management with medications for drug abuse

Contingency management (CM) procedures, which provide concrete reinforcers or rewards contingent on verification of discrete targeted behaviors, such as drug-free urines, have been demonstrated to be effective in a number of clinical trials. However, to date there have been only a few that have capitalized on the unique strengths and capabilities of CM as an ideal platform to improve response to or address weaknesses of many pharmacotherapies used in the treatment of drug abuse. In this review, we describe the multiple potential uses of CM as a platform for pharmacotherapy, including reducing illicit drug use in the context of agonist therapies; fostering medication compliance with antagonists, aversive agents and HIV medications; fostering a period of abstinence prior to initiation of agents used to treat comorbid psychiatric conditions or in the context of vaccines to foster adequate periods of abstinence while titer levels are building; and to enhance the effectiveness of anticraving agents through additive or synergistic effects. Although its multiple strengths render it an almost perfect platform, CM does have some weaknesses that have limited its use to date, including cost, the short-term nature of its effects, and need for training. Future treatment development of CM as a medication platform needs to counter these issues by focusing on CM applications with large potential benefit, developing simple or automated methods for CM delivery and placing greater emphasis on the process of transitioning away from formal CM treatment.

Effects of varying the monetary value of voucher-based incentives on abstinence achieved during and following treatment among cocaine-dependent outpatients

AIMS

This study examined whether increasing the amount of abstinence achieved during outpatient treatment for cocaine dependence is an effective method for increasing longer-term cocaine abstinence.

DESIGN

A two-condition, parallel groups, randomized controlled trial was conducted.

SETTING

The trial was conducted in a university-based research clinic.

PARTICIPANTS

A total of 100 cocaine-dependent outpatients participated in the trial.

INTERVENTION

Participants were assigned randomly to receive treatment based on the community reinforcement approach (CRA) plus voucher-based incentives set at a relatively high monetary value (maximal value = $1995/12 weeks) or CRA with vouchers set at a relatively low monetary value (maximal value = $499/12 weeks). Vouchers were earned contingent on cocaine-negative urinalysis results during the initial 12 weeks of the 24-week outpatient treatment.

MEASUREMENTS

Outcomes were evaluated using urine-toxicology testing, questionnaires and other self-report instruments.

FINDINGS

Increasing voucher value increased the duration of continuous cocaine abstinence achieved during the 24-week treatment period. Point-prevalence cocaine abstinence assessed every 3 months throughout an 18-month follow-up period was greater in the high- than low-value voucher conditions. The duration of abstinence achieved during treatment predicted abstinence during follow-up, although that relationship weakened over time.

CONCLUSIONS

Increasing the value of abstinence-contingent incentives during the initial weeks of treatment appears to represent an effective method for increasing during-treatment and longer-term cocaine abstinence, but the positive association of during-treatment abstinence with longer-term outcome dissipates with time.

The use of contingency management and motivational/skills-building therapy to treat young adults with marijuana dependence

Marijuana-dependent young adults (N = 136), all referred by the criminal justice system, were randomized to 1 of 4 treatment conditions: a motivational/skills-building intervention (motivational enhancement therapy/cognitive-behavioral therapy; MET/CBT) plus incentives contingent on session attendance or submission of marijuana-free urine specimens (contingency management; CM), MET/CBT without CM, individual drug counseling (DC) plus CM, and DC without CM. There was a significant main effect of CM on treatment retention and marijuana-free urine specimens. Moreover, the combination of MET/CBT plus CM was significantly more effective than MET/CBT without CM or DC plus CM, which were in turn more effective than DC without CM for treatment attendance and percentage of marijuana-free urine specimens. Participants assigned to MET/CBT continued to reduce the frequency of their marijuana use through a 6-month follow-up.

Behavioral economic analysis of opioid consumption in heroin-dependent individuals: effects of unit price and pre-session drug supply

Behavioral economic analysis has been used to investigate factors underlying drug consumption in laboratory animals and, increasingly, in human drug abusers. However, there are few studies in heroin abusers, especially those who are not in treatment; such studies may be valuable for understanding the mechanisms of persistent drug use. This study investigated effects of unit price (UP) and pre-session supply of hydromorphone (HYD) on choice and consumption of HYD. Heroin-dependent research volunteers (n=13) stabilized on buprenorphine 8 mg/day completed this eight-session inpatient study. In sessions 1-2, participants sampled two total HYD doses (12 and 24 mg IM) that could be earned in later sessions. In each of the final six sessions, volunteers were given access to a 12-trial choice progressive ratio schedule lasting 3h. On each trial, volunteers could earn a HYD unit dose (1 or 2 mg, for a maximum of 12 or 24 mg, respectively) or money (US dollars 2, for a maximum of US dollars 24). Fixed ratio requirements increased exponentially, generating 24 unit prices for behavioral economic analysis. Before some choice sessions, volunteers could choose (FR 1) to receive extra HYD (12 or 24 mg; at 0915), whereas on other days no supplement was available. HYD choice and peak responding (breakpoint, O(max)) measures increased with unit dose, decreased with pre-session supplements, and were greater among volunteers who used cocaine prior to the experiment. Taking pre-session supplements decreased P(max) and made group-percent HYD consumption more demand-elastic. Consumption was functionally equivalent at differing FR/unit dose combinations. Thus, opioid demand in heroin-dependent individuals not in treatment is a function of drug supply, unit price, and cocaine use.

Emerging pharmacological strategies in the fight against cocaine addiction

Cocaine addiction continues to be an important public health problem worldwide. At present, there are no proven pharmacotherapies for cocaine addiction. The studies reviewed here revealed a number of emerging targets for cocaine pharmacotherapy. First, disulfiram, a medication with dopaminergic effects, reduced cocaine use in a number of clinical trials. Second, GABA medications, tiagabine and topiramate, were found promising in clinical trials. Third, a beta-adrenergic blocker, propranolol, may be effective especially among cocaine-addicted individuals with high withdrawal severity. Fourth, treatment with a stimulant medication, modafinil, has reduced cocaine use. Last, a cocaine vaccine that slows entry of cocaine into the brain holds promise. These promising findings need to be further tested in controlled clinical trials.

Early impact of methadone induction for heroin dependence: differential effects of two dose sequences in a randomized controlled study

The pharmacodynamic and pharmacokinetic effects of 2 methadone (METH) induction dose sequences were evaluated in this 15-day outpatient experimental protocol. Heroin-dependent, non-treatment-seeking volunteers were randomly assigned (stratified for gender, race, and route of heroin use) to 2 groups. In 1 sequence, METH doses ascended (28, 56, then 84 mg/day; stepwise, n = 18), whereas in the other sequence doses escalated, then tapered (28-84 mg on Days 1-6 to 56 mg/day; rapid, n = 16). A contingency-management intervention was common to both groups. Drug use and heroin craving and opioid withdrawal symptoms decreased, whereas agonist symptoms and positive mood increased overall across days for both groups. Plasma concentrations and the acute reinforcing effects of METH paralleled each dose sequence. Stepwise relative to rapid METH induction significantly decreased heroin craving and opioid withdrawal symptoms and increased agonist symptoms and positive mood but did not significantly improve drug use or retention. Although these specific dosing procedures would not necessarily be used in clinical settings, they provide a procedural template that might be applied safely and effectively with a broader range of treatment-seeking individuals.

A controlled trial of amlodipine for cocaine dependence: a negative report

Preclinical models of cocaine dependence have shown favorable reductions in cocaine use using dihydropyridine calcium channel antagonists. This is one of the first reports testing the efficacy of the long-acting calcium channel antagonist, amlodipine, for the treatment of cocaine dependence. This was a 12-week, double-blind, randomized, placebo-controlled, parallel patient group trial of amlodipine vs. placebo for the treatment of cocaine dependence. One hundred and sixteen subjects participated in a 12-week medication trial in which 60 subjects received medication and 56 received placebo. Subjects in both groups received up to 12 standard manual-driven cognitive behavioral therapy sessions. Overall, drop-out rate for both groups was high, with only about 20% of subjects completing all 12 weeks of treatment. Both groups showed comparable levels of medication compliance and therapy attendance. In the end, amlodipine was no more effective than placebo in reducing craving or measured levels of cocaine use.

Choosing a behavioral therapy platform for pharmacotherapy of substance users

Behavioral therapy platforms have become virtual requirements in pharmacotherapy trials due to their utility in reducing noise variability, preventing differential medication adherence and protocol attrition, enhancing statistical power and addressing ethical issues in placebo-controlled trials. Selecting an appropriate behavioral platform for a particular trial requires study-specific tailoring, taking into account both the stage of development of the medication being evaluated, as well as the specific strengths and weaknesses of a broad array of available empirically supported behavioral therapies and the range of their possible targets (e.g., enhancing medication adherence, preventing attrition, addressing co-morbid problems, fostering abstinence, and targeting specific weaknesses of the pharmacologic agent). Choosing a suitable behavioral platform also requires consideration of the characteristics of the population to be treated, stage of scientific knowledge regarding the medication's effects, appropriate balance of internal and external validity, and consideration of potential ceiling effects. Available manualized behavioral treatments are reviewed, noting their strengths and limitations as behavioral therapy platforms for pharmacotherapy trials and as potential concomitant therapies in clinical practice.