Wendy Y. Cheng

Dronabinol for the treatment of cannabis dependence: A randomized, double-blind, placebo-controlled trial

Cannabis dependence is a substantial public health problem. Behavioral treatments have shown promise, but there are no effective medications for cannabis dependence. The purpose of this study was to evaluate the safety and efficacy of dronabinol, a synthetic form of delta-9-tetrahydrocannabinol, a naturally occurring pharmacologically active component of marijuana, in treating cannabis dependence. 156 cannabis-dependent adults were enrolled in a randomized, double-blind, placebo-controlled, 12-week trial. After a 1-week placebo lead-in phase, participants were randomized to receive dronabinol 20mg twice a day or placebo. Doses were maintained until the end of week 8 and then tapered off over 2 weeks. All participants received weekly motivational enhancement and relapse prevention therapy. Marijuana use was assessed using the timeline follow back method. There was no significant difference between treatment groups in the proportion of participants who achieved 2 weeks of abstinence at the end of the maintenance phase (dronabinol: 17.7%; placebo: 15.6%). Although both groups showed a reduction in marijuana use over time, there were no differences between the groups. Treatment retention was significantly higher at the end of the maintenance phase on dronabinol (77%), compared to placebo (61%) (P=.02), and withdrawal symptoms were significantly lower on dronabinol than placebo (P=.02). This is the first trial using an agonist substitution strategy for treatment of cannabis dependence. Dronabinol showed promise, it was well-tolerated, and improved treatment retention and withdrawal symptoms. Future trials might test higher doses, combinations of dronabinol with other medications with complementary mechanisms, or with more potent behavioral interventions.

A preliminary trial: double-blind comparison of nefazodone, bupropion-SR, and placebo in the treatment of cannabis dependence.

The present study investigated the efficacy of nefazodone and bupropion-sustained release for treating cannabis dependence. A double-blind, placebo-controlled, piggy back design was employed to assess if nefazodone and bupropion-sustained release increased the probability of abstinence from cannabis and reduced the severity of cannabis dependence and cannabis withdrawal symptoms during a 13-week outpatient treatment program. One-hundred and six participants (Mean = 32 years; females n = 25) were randomized to one of three medication conditions (nefazodone, bupropion-sustained release, or placebo) and participated in a weekly, individually based coping skills therapy program. Results indicated an increased probability of achieving abstinence over the course of treatment and a decrease in the severity of cannabis dependence and the withdrawal symptom of irritability. There were no significant effects demonstrated for nefazodone and bupropion-sustained release on cannabis use or cannabis withdrawal symptoms. The results indicate nefazodone and bupropion-sustained release may have limited efficacy in treating cannabis dependence.

Old dogs and new skills: how clinician characteristics relate to motivational interviewing skills before, during, and after training.

OBJECTIVE The relationships between the occupational, educational, and verbal-cognitive characteristics of health care professionals and their motivational interviewing (MI) skills before, during, and after training were investigated. METHOD Fifty-eight community-based addiction clinicians (M = 42.1 years, SD = 10.0; 66% Female) were assessed prior to enrolling in a 2-day MI training workshop and being randomized to one of three post-workshop supervision programs: live supervision via tele-conferencing (TCS), standard tape-based supervision (Tape), or workshop training alone. Audiotaped sessions with clients were rated for MI skillfulness with the Motivational Interviewing Treatment Integrity (MITI) coding system v 2.0 at pre-workshop and 1, 8, and 20 weeks post-workshop. Correlation coefficients and generalized linear models were used to test the relationships between clinician characteristics and MI skill at each assessment point. RESULTS Baseline MI skill levels were the most robust predictors of pre- and post-supervision performances. Clinician characteristics were associated with MI Spirit and reflective listening skill throughout training and moderated the effect of post-workshop supervision method on MI skill. TCS, which provided immediate feedback during practice sessions, was most effective for increasing MI Spirit and reflective listening among clinicians with no graduate degree and stronger vocabulary performances. Tape supervision was more effective for increasing these skills among clinicians with a graduate degree. Further, TCS and Tape were most likely to enhance MI Spirit among clinicians with low average to average verbal and abstract reasoning performances. CONCLUSIONS Clinician attributes influence the effectiveness of methods used to promote the acquisition of evidence-based practices among community-based practitioners.

Atomoxetine Treatment for Cocaine Abuse and Adult Attention Deficit/Hyperactivity Disorder (ADHD): A Preliminary Open Trial

The purpose of this 12-week open-label trial was to evaluate the potential utility of atomoxetine for the treatment of attention deficit/hyperactivity disorder (ADHD) in cocaine-dependent treatment seekers. The sample consisted of 20 participants who met DSM-IV-TR criteria for ADHD and cocaine dependence. Using several measures to assess ADHD, there was a significant reduction in ADHD symptoms. There was no significant decrease in cocaine use throughout the trial. Taken together, although cocaine-dependent individuals showed some reduction in ADHD symptoms while receiving atomoxetine, the high dropout rate and lack of impact on cocaine use may limit its utility in adults with ADHD who are currently abusing cocaine.

A placebo-controlled trial of memantine for cocaine dependence with high-value voucher incentives during a pre-randomization lead-in period

Preclinical findings suggest that the inhibition of NMDA glutamatergic neurotransmission may have beneficial effects in the treatment of cocaine dependence. We hypothesized that memantine, a low potency, uncompetitive NMDA receptor antagonist, would be safe and effective in the treatment of cocaine dependence, particularly in preventing relapse to cocaine use in abstinent individuals. Cocaine dependent patients (N=112) were enrolled. The trial began with a 2-week placebo lead-in period during which patients received high-value voucher contingency management to induce abstinence. Participants were then randomized to receive either memantine 20mg bid (N=39) or placebo (N=42) for 12-weeks in combination with individual relapse-prevention therapy. The randomization was stratified by abstinence status during the lead-in period. The primary outcome was the weekly proportion of days of cocaine use. There were no significant differences in cocaine use outcome between the groups treated with memantine versus placebo. Thus, the efficacy of memantine 40 mg/d for the treatment of cocaine dependence was not supported. Urine-confirmed abstinence during the lead-in period was achieved by 44% of participants, and was a strong predictor of subsequent cocaine abstinence during the trial. This suggests that this clinical trial design, an intensive behavioral intervention during a lead-in period, resolves cocaine dependent patients into two subgroups, one that rapidly achieves sustained abstinence and may not need a medication, and another that displays persistent cocaine use and would most likely benefit from a medication to help induce abstinence. Targeting the latter subgroup may advance medication development efforts.

A Pilot Study of Neurocognitive Function in Older and Younger Cocaine Abusers and Controls

This pilot study compared basic neurocognitive functioning among older and younger cocaine abusers and control participants, as a preliminary assessment of whether specific cognitive deficits exist in an aged cocaine-abusing population. We hypothesized an interaction between aging and cocaine abuse, such that older cocaine abusers would exhibit decreased neuropsychological test performance relative to both younger cocaine abusers and older control participants. Four groups (n = 20 each) were examined: older cocaine abusers (ages 51-70), younger cocaine abusers (ages 21-39), and two non-illicit substance-using control groups. Basic neuropsychological and psychiatric measures were administered to all participants. Older participants performed more poorly than younger participants on the Mini-Mental State Examination (MMSE, p < .01), Digit Span Backward (p < .01), and Trail Making Test (TMT) Parts A and B (p < .01). Cocaine abusers performed more poorly than controls on TMT A (p < .01). Older and younger cocaine abusers used similar amounts of cocaine (p > .05). Older cocaine abusers performed more poorly than older control participants and younger cocaine abusers on the Digit Span Forward (p < .0125). Older cocaine abusers also performed more poorly than younger cocaine abusers on TMT A (p < .0125). This study provides preliminary evidence that older cocaine abusers use a significant amount of cocaine and that there is an interaction between aging and cocaine abuse on psychomotor speed, attention, and short-term memory. Future examination of neurocognitive function in older cocaine abusers is clearly warranted. 

A PLACEBO CONTROLLED TRIAL OF MEMANTINE AS AN ADJUNCT TO ORAL NALTREXONE FOR OPIOID DEPENDENCE

BACKGROUND Preclinical findings suggest that the inhibition of NMDA glutamatergic neurotransmission may have beneficial effects in the treatment of opioid dependence. AIMS We hypothesized that memantine, a low-potency, uncompetitive NMDA receptor antagonist, would be safe and effective when used as an adjunct to oral naltrexone in the treatment of opioid dependence, particularly in preventing relapse to opiate use in detoxified individuals. METHODS Opioid-dependent participants (N=112) were enrolled. Following detoxification all participants were inducted onto oral naltrexone and were randomized to receive memantine 15 mg bid (N=27), memantine 30 mg bid (N=27) or placebo (N=27) for 12-weeks in combination with naltrexone 50mg/day and individual relapse-prevention therapy. The primary outcome was the retention in treatment since treatment dropout is most commonly associated with relapse to opiate use. RESULTS Twenty-six percent of participants withdrew from treatment prior to starting naltrexone. Of those that were randomized 35% completed 4 weeks only, and 24% completed all 12 weeks of treatment. There was no significant difference in treatment retention or heroin use, opiate withdrawal symptoms and craving between the groups treated with memantine vs. placebo. CONCLUSION Thus, the efficacy of memantine 30 or 60 mg/day as an adjunct to oral naltrexone for the treatment of opiate dependence was not supported.

The association between naltrexone treatment and symptoms of depression in opioid-dependent patients

Objective: To examine the change in total symptoms, and symptom clusters, of depression in newly abstinent opioid-dependent individuals being treated with depot naltrexone (Depotrex; Biotek, Inc., Wellesley, MA). Method: In a series of opioid-dependent patients (N = 34) treated with naltrexone maintenance and relapse prevention therapy, mood was assessed with a 17-item Hamilton Depression (HAM-D) Scale and subscale scores at baseline, and after naltrexone induction at 2- and 4-week post-baseline. Data were analyzed using generalized estimated equation (GEE) models. Results: Patients demonstrated high baseline affective burden and significant improvement of depression scores over a 4-week period post-baseline (F2.66 = 8.88; p = .0004). Somatic and cognitive-affective subscale scores significantly declined as well as the seven individual item scores. By contrast, the “late insomnia” item score significantly increased at 2 weeks post-baseline. Conclusions and Scientific Significance: Naltrexone induction and maintenance in newly abstinent opioid-dependent individuals does not appear to be associated with worsening of depression; however, it may be associated with sleep impairment early in treatment.

Antisocial Behavioral Syndromes in Cocaine and Cannabis Dependence

Antisocial personality disorder (ASPD) is highly associated with substance use disorders (SUD). In addition to the full ASPD syndrome, which requires both childhood conduct disorder and the adult features, other antisocial behavioral syndromes, including conduct disorder (CD) alone without the adult syndrome, and the adult antisocial behavioral syndrome without childhood CD (AABS) are also frequently diagnosed in patients with SUD. The aim of this study was to compare the rates of these various ASPD syndromes between cocaine- and cannabis-dependent individuals seeking treatment. A structured interview for ASPD excluding symptoms that occurred solely in the context of substance use was conducted in 241 outpatients (cocaine dependence, n = 111; cannabis dependence, n = 130). Overall, the proportion of substance-dependent individuals in this study with AABS was significantly larger than the proportion with ASPD (30.9% vs. 17.3%). A diagnosis of CD-only, where CD did not progress to ASPD, was uncommon. No significant differences in the prevalence of antisocial behavioral syndrome diagnoses were found between cocaine- and cannabis-dependent patients. Antisocial behavioral syndrome diagnosis did not influence treatment retention. Antisocial behavioral syndromes are commonly diagnosed in patients with SUD and future research should evaluate prognostic implications of AABS compared to ASPD in a variety of clinical treatment settings.

A Randomized, Double-Blind, Placebo-Controlled Trial of Venlafaxine for the Treatment of Depressed Cocaine-Dependent Patients

OBJECTIVE This study tested the hypothesis that the antidepressant venlafaxine would be an effective treatment for cocaine abusers with concurrent depressive disorders. METHODS This was a randomized, 12-week, double-blind, placebo-controlled trial of outpatients (N = 130) meeting DSM-IIIR criteria for cocaine dependence and major depression or dysthymia (by SCID interview). Participants were treated with venlafaxine, up to 300 mg/day versus placebo. All patients received weekly individual manual-guided relapse prevention therapy. Weekly outcome measures included Clinical Global Impression Scale (CGI), self-reported cocaine use, urine toxicology and the Hamilton Depression Scale (Ham-D). RESULTS Mood response, defined as a 50% reduction in the Ham-D between randomization and end of study, was 41% (26/64) on venlafaxine, and 33% (22/66) on placebo (p = .39). Measures of depression (Ham-D and CGI) improved more rapidly on venlafaxine than placebo, but these differences disappeared by weeks 6-8. Cocaine outcomes did not differ between treatment groups, and the proportion of patients achieving three or more consecutive weeks of urine-confirmed abstinence was low (venlafaxine: 16%; placebo: 15%). Reduction in cocaine use was associated with mood response. CONCLUSIONS Overall, venlafaxine was not superior to placebo on either mood or cocaine use outcomes. Mood improvement was associated with improvement in cocaine use. However, placebo mood response was only moderate, and the proportion of patients achieving sustained abstinence was low. This suggests that the subgroup of cocaine-dependent patients with depressive disorders is relatively treatment resistant, and that further research is needed to improve outcomes for these patients.