New methodologies for pharmacological treatment trials for alcohol dependence

Frontal EEG response to alcohol craving elicited by individually tailored video cues

BACKGROUND

Most findings on the pathophysiology of alcoholism are based on studies using resting-state electroencephalography (EEG). There are few studies on cue-induced craving and on its utility as an electrophysiological index. We examined quantitative EEG (qEEG) activities in alcoholics and social drinkers exposed to video cues and compared their association with subjective alcohol craving and other related psychiatric symptoms, including anxiety and depression.

METHODS

This is a between-subjects design. Adult male alcoholics (n = 34) and healthy social drinkers (n = 33) participated. In a laboratory, EEGs were recorded while the participants were presented with craving-inducing video stimuli. Measures used were the Visual Analog Scale (VAS) for subjective alcohol craving, Alcohol Urge Questionnaire (AUQ), Michigan Alcoholism Screening Test (MAST), Beck Anxiety Inventory (BAI), and Beck Depression Inventory (BDI) scores.

RESULTS

One-way analysis of covariance with age showed that alcoholics had significantly increased beta activity in the right DLPFC region (F4) (F = 4.029, p = 0.049), compared to social drinkers when craving-inducing stimuli were presented. Beta activity at the F4 electrode was positively correlated with AUQ (r = .284, p = 0.021), BAI (r = .398, p = 0.001), BDI (r = .291, p = 0.018), and changes in VAS (r = .292, p = 0.017) scores in both alcoholics and social drinkers. In alcoholics, beta activity was significantly correlated with BAI (r = .392, p = 0.024).

CONCLUSIONS

These findings imply functional importance of hyperarousal and negative emotions upon exposure to craving-inducing cues. Frontal EEG indices with beta power could serve as an objective electrophysiological index of craving induced by individually tailored video cues in alcohol consumption behavior.

Effects of pharmacological and genetic regulation of COMT activity in alcohol use disorder: a randomized, placebo-controlled trial of tolcapone

Alcohol Use Disorder (AUD) is characterized by loss of control over drinking. Behavioral control is mediated, in part, by cortical dopamine signaling. Inhibition of catechol-O-methyltransferase (COMT), the enzyme primarily responsible for cortical dopamine inactivation, may increase cortical dopamine, especially among individuals with genetically mediated lower dopaminergic tone, such as COMT rs4680 (val158met) val-allele homozygotes. This study was a randomized, placebo-controlled, pharmacogenetic trial of the COMT inhibitor tolcapone. Ninety non-treatment-seeking AUD individuals were prospectively genotyped for rs4680 and randomized to tolcapone (200 mg t.i.d.) or placebo for 8 days. At baseline and on day 7, peripheral COMT activity was assayed, and participants completed an fMRI alcohol cue-reactivity task; on day 8, they completed a bar-lab paradigm. Primary outcomes were: (1) natural drinking during the medication period; (2) alcohol self-administration in the bar lab; and (3) alcohol cue-elicited cortical (right inferior frontal gyrus [rIFG]) and ventral striatal activation. At baseline, the rs4680 val-allele had an additive effect on COMT activity. Tolcapone, relative to placebo, reduced COMT activity in all genotype groups. COMT genotype moderated tolcapone's effect on drinking during the medication period and in the bar lab, such that tolcapone, relative to placebo, reduced drinking only among val-allele homozygotes. Tolcapone did not affect cue-elicited ventral striatal activation but reduced rIFG activation; less rIFG activation on day 7 was associated with less drinking during the medication period. Taken together, these data suggest that COMT inhibition may reduce drinking specifically among individuals genetically predisposed to excessive COMT activity and potentially low cortical dopamine tone.ClinicalTrials.gov identifier: NCT02949934 https://clinicaltrials.gov/ct2/show/NCT02949934.

Dopaminergic Genetic Variation Influences Aripiprazole Effects on Alcohol Self-Administration and the Neural Response to Alcohol Cues in a Randomized Trial

Dopamine (DA) signaling regulates many aspects of Alcohol Use Disorder (AUD). However, clinical studies of dopaminergic medications, including the DA partial agonist aripiprazole (APZ), have been inconsistent, suggesting the possibility of a pharmacogenetic interaction. This study examined whether variation in DA-related genes moderated APZ effects on reward-related AUD phenotypes. The interacting effects of APZ and a variable number tandem repeat (VNTR) polymorphism in DAT1/SLC6A3 (the gene encoding the DA transporter (DAT)) were tested. In addition, interactions between APZ and a genetic composite comprising the DAT1 VNTR and functional polymorphisms in catechol-O-methyltransferase (COMT), DRD2, and DRD4 were evaluated. Ninety-four non-treatment-seeking individuals with AUD were genotyped for these polymorphisms, randomized to APZ (titrated to 15 mg) or placebo for 8 days, and underwent an fMRI alcohol cue-reactivity task (day 7; n=81) and a bar lab paradigm (day 8). Primary outcomes were alcohol cue-elicited ventral striatal (VS) activation and the number of drinks consumed in the bar lab. DAT1 genotype significantly moderated medication effects, such that APZ, relative to placebo, reduced VS activation and bar-lab drinking only among carriers of the DAT1 9-repeat allele, previously associated with lower DAT expression and greater reward-related brain activation. The genetic composite further moderated medication effects, such that APZ reduced the primary outcomes more among individuals who carried a larger number of DAT1, COMT, DRD2, and DRD4 alleles associated with higher DA tone. Taken together, these data suggest that APZ may be a promising AUD treatment for individuals with a genetic predisposition to higher synaptic DA tone.

Predictors of Naltrexone Response in a Randomized Trial: Reward-Related Brain Activation, OPRM1 Genotype, and Smoking Status

Naltrexone reduces drinking among individuals with alcohol use disorders (AUDs), but it is not effective for everyone. Variability in its effects on reward-related brain activation, genetic variation, and/or cigarette smoking may account for this mixed response profile. This randomized clinical trial tested the effects of naltrexone on drinking and alcohol cue-elicited brain activation, evaluated whether OPRM1 A118G genotype or smoking moderated these effects, and explored whether the effects of medication on cue-elicited activation predicted subsequent drinking. One hundred and fifty-two treatment-seeking individuals with alcohol dependence, half preselected to carry at least one A118G G (Asp) allele, were randomized to naltrexone (50 mg) or placebo for 16 weeks and administered an fMRI alcohol cue reactivity task at baseline and after 2 weeks of treatment. Naltrexone, relative to placebo, significantly reduced alcohol cue-elicited activation of the right ventral striatum (VS) between baseline and week 2 and reduced heavy drinking over 16 weeks. OPRM1 genotype did not significantly moderate these effects, but G-allele carriers who received naltrexone had an accelerated return to heavy drinking after medication was stopped. Smoking moderated the effects of medication on drinking, such that naltrexone was superior to placebo only among smokers. The degree of reduction in right VS activation between scans interacted with medication in predicting subsequent drinking, such that individuals with greater reduction in activation who received naltrexone, but not placebo, experienced the least heavy drinking during the following 14 weeks. These data replicate previous findings that naltrexone reduces heavy drinking and reward-related brain activation among treatment-seeking individuals with AUDs, and indicate that smoking and the magnitude of reduction in cue-elicited brain activation may predict treatment response.

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

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

A randomized clinical trial of alcohol care management delivered in Department of Veterans Affairs primary care clinics versus specialty addiction treatment

BACKGROUND

Alcohol use disorder is one of the leading causes of disability worldwide. Despite the availability of efficacious treatments, few individuals with an alcohol use disorder are actively engaged in treatment. Available evidence suggests that primary care may play a crucial role in the identification of patients with an alcohol use disorder, delivery of interventions, and the success of treatment.

OBJECTIVE

The principal aims of this study were to test the effectiveness of a primary care-based Alcohol Care Management (ACM) program for alcohol use disorder and treatment engagement in veterans.

DESIGN

The design of the study was a 26-week single-blind randomized clinical trial. The study was conducted in the primary care practices at three VA medical centers. Participants were randomly assigned to treatment in ACM or standard treatment in a specialty outpatient addiction treatment program.

PARTICIPANTS

One hundred and sixty-three alcohol-dependent veterans were randomized.

INTERVENTION

ACM focused on the use of pharmacotherapy and psychosocial support. ACM was delivered in-person or by telephone within the primary care clinic.

MAIN MEASUREMENTS

Engagement in treatment and heavy alcohol consumption.

KEY RESULTS

The ACM condition had a significantly higher proportion of participants engaged in treatment over the 26 weeks [OR = 5.36, 95 % CI = (2.99, 9.59)]. The percentage of heavy drinking days were significantly lower in the ACM condition [OR = 2.16, 95 % CI = (1.27, 3.66)], while overall abstinence did not differ between groups.

CONCLUSIONS

Results demonstrate that treatment for an alcohol use disorder can be delivered effectively within primary care, leading to greater rates of engagement in treatment and greater reductions in heavy drinking.

A cross-sectional study of attitudes about the use of genetic testing for clinical care among patients with an alcohol use disorder

AIM

Modification and individualization of medical treatments due to genetic testing has the potential to revolutionize healthcare delivery. As evidence mounts that genetic testing may improve treatment decisions for patients with alcohol use disorder (AUD), we explored patient concerns and attitudes toward genetic testing.

METHODS

Subjects of two USA cross-sectional AUD studies were surveyed regarding their attitudes regarding the use of genetic testing for AUD treatment.

RESULTS

Four hundred and fifty-seven participants were surveyed. Overall, subjects showed a high degree of willingness to provide DNA for clinical use and recognized genetics as important to the pathophysiology of a number of disorders including AUD. There were, however, significant concerns expressed related to insurance denial or employment problems.

CONCLUSION

We found that patients enrolled in AUD studies had some concerns about use of genetic testing. The patients in these two samples were, however, willing and knowledgeable about providing DNA samples.

Assessment of riboflavin as a tracer substance: comparison of a qualitative to a quantitative method of riboflavin measurement

BACKGROUND

Noncompliance with medications may have major impacts on outcomes measured in research, potentially distorting the validity of controlled clinical trials. Riboflavin is frequently used in trials as a marker of adherence. It can be combined with study medication and is excreted in urine where it fluoresces under UV light. This study compares qualitative visual inspection of fluorescence to quantitative fluorometric analysis of riboflavin concentration in its ability to detect the presence of riboflavin in urine.

METHODS

Twenty-four volunteers received 0mg, 25mg, and 50mg doses of riboflavin under single-blind conditions, with 20 also receiving a 100mg dose. Five serial urine samples were collected over the following 36h. Quantitative measurement of riboflavin by fluorometric analysis and qualitative assessment of each sample using visual inspection were performed.

RESULTS

The overall false positive rate for qualitative assessment was 53%. For quantitative assessment, a riboflavin concentration of 900ng/mL was established to classify positive samples. More than 80% of samples were positive 2-24h following ingestion of 25mg and 50mg, and less than 80% were positive at 36h. At least 95% of observations for the 100mg dose were above 900ng/mL at all timepoints.

CONCLUSIONS

Quantitative fluorometric assessment is superior to qualitative visual inspection alone in determining medication adherence. The combination of 25-50mg of daily riboflavin and a cut-off level of 900ng/mL allows for the acceptable sensitivity of missing detection of non-compliant participants while preserving a high level of power to detect all cases of medication compliance.

Do manualized psychosocial interventions help reduce relapse among alcohol-dependent adults treated with naltrexone or placebo? A meta-analysis

BACKGROUND

 During the past decade, several novel medication treatments and psychosocial interventions have been tested. Overall, their impact on reducing alcohol use and preventing relapse has been modest. These outcomes have spurred researchers to investigate whether the addition of manualized psychosocial therapies with demonstrated efficacy to pharmacotherpy would have a synergistic effect.

OBJECTIVES

 We conducted a meta-analysis to test the hypothesis that the addition of manualized psychosocial therapies would reduce the frequency of relapse.

RESULTS

 This review analyzed data from six studies. Among studies that used random assignment to manually guided psychosocial interventions, the rates of relapse between the naltrexone plus a psychosocial intervention and naltrexone without a psychosocial intervention were very similar. Among patients allocated to placebo, similar rates of relapse were also found between Cognitive Behavioral Therapy (CBT) and non-CBT. In studies which used manualized psychotherapies as a platform, relapse rates were similar between naltrexone and placebo. In contrast, studies using Treatment As Usual psychotherapy as a platform demonstrated lower rates of relapse in the naltrexone group, compared to placebo group.

CONCLUSIONS

 We conclude that CBT does not appear to offer benefits beyond those derived from study medications.

SCIENTIFIC SIGNIFICANCE

 The benefit of the addition of CBT to medication in preventing relapse may be limited.

Naltrexone modification of drinking effects in a subacute treatment and bar-lab paradigm: influence of OPRM1 and dopamine transporter (SLC6A3) genes

BACKGROUND

Naltrexone is moderately effective for the treatment of alcohol dependence, but there is great individual variability. The opioid receptor (OPRM1) single nucleotide polymorphism (SNP) asn40asp has been shown to alter alcohol and naltrexone response in animals and humans. In addition, the brain opioid and dopamine systems interact and might underlie drinking and craving. This study investigated the effects of the OPRM1 SNP and dopamine transporter (DAT) variable number of tandem repeat (VNTR) genetic differences on drinking, alcohol effects, and naltrexone response under controlled conditions in nontreatment-seeking alcoholics.

METHODS

Two hundred and sixty-five nontreatment-seeking individuals with alcohol dependence were genotyped a priori for the OPRM1 asn40asp SNP and post hoc for DAT (SLC6A3) 9 and 10 VNTRs. Asp40 carriers (n = 43) and matched asn40 homozygotes (n = 40) were randomized to naltrexone or placebo for 7 days before receiving a priming drink and limited-access alcohol consumption in a bar-lab setting. Effects of genotypes on natural drinking as well as drinking, alcohol effects, and response to naltrexone in the bar-lab setting were examined by genotype.

RESULTS

There were no significant main effects of naltrexone or OPRM1 genotype, or any medication by OPRM1 interaction, on drinking variables. However, in individuals who had at least one DAT 9 VNTR, and who were also OPRM1 asn40 homozygotes, naltrexone reduced drinks/d consumed under natural conditions (p = 0.006), but not in the bar-lab. OPRM1 asn40 homozygotes (p = 0.028) and DAT 9 VNTR carriers (p = 0.032) had more stimulation to alcohol after the priming drink.

CONCLUSIONS

This study does not support a salient role for the OPRM1 asp40 alone in predicting drinking or naltrexone effects. However, although exploratory and in need of replication, it introduces the possibility that epistasis between the OPRM1 gene and DAT gene might need to be taken into account when examining differential genetic response to alcohol or medication treatment, especially in early-stage alcoholics.

HIV, alcohol dependence, and the criminal justice system: a review and call for evidence-based treatment for released prisoners

BACKGROUND

People with both HIV and alcohol use disorders (AUDs) are disproportionately concentrated within the U.S. criminal justice system; approximately one-quarter of all people with HIV cycle through the system each year. HIV-infected prisoners with AUDs face many obstacles as they transition back to the community. Specifically, although they have impressive HIV treatment outcomes during the period of incarceration while they are free from alcohol; upon [corrected] release, however, they face inordinate challenges including relapse to alcohol use resulting in significant morbidity and mortality.

OBJECTIVE

To review the existing literature regarding the relationship of HIV and treatment for AUDs within the criminal justice system in an effort to determine "best practices" that might effectively result in improved treatment of HIV and AUDs for released prisoners.

METHODS

PubMed, PsychInfo and Medline were queried for articles published in English from 1990 to 2009. Selected references from primary articles were also examined.

RESULTS

Randomized controlled trials affirm the role of pharmacotherapy using naltrexone (NTX) as the therapeutic option conferring the best treatment outcome for AUDs in community settings. Absent from these trials were inclusion of released prisoners or HIV-infected individuals. Relapse to alcohol abuse among HIV-infected prisoners is associated with reduced retention in care, poor adherence to antiretroviral therapy with consequential poor HIV treatment outcomes and higher levels of HIV risk behaviors.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Untreated alcohol dependence, particularly for released HIV-infected prisoners, has negative consequences both for the individual and society and requires a concentrated effort and rethinking of our existing approaches for this vulnerable population.

Combined effects of alcohol and hepatitis C: a secondary analysis of alcohol use biomarkers and high-risk behaviors from two medication trials for alcohol dependence

OBJECTIVES

The goal of this secondary analysis was to examine the combined effects of HCV infection and recent alcohol use on baseline biologic markers of alcohol consumption in two outpatient medication trials for alcohol dependence. In addition, the relationship between Hepatitis C virus (HCV) infection and behavioral risk factors for HCV infection in these clinical populations were examined.

METHODS

Data (n=345) from two randomized, placebo-controlled trials of naltrexone and psychosocial treatment for alcohol dependence (Study I, n=212) and comorbid alcohol and cocaine dependence (Study II, n=133) were used to examine baseline measures of HCV risk behaviors (injection drug use, needle sharing), and biomarkers of alcohol use (AST, ALT, GGT and CDT) were compared by HCV serostatus first within each study and then across studies.

RESULTS

Although groups had differing sociodemographic profiles (as indicated by race, marital status, level of education) subjects in Study I exhibited no statistically significant differences from the Study II cohort in HCV prevalence (12.7 vs. 20.0%, p=0.07), lifetime history of injection drug use (13.8 vs. 22.0%, p=0.74), lifetime history of needle sharing (9.1 vs. 18.0%, p=0.62). As such, the data from both studies were analyzed together. Regardless of drinking status, HCV infection was significantly associated with an upward shift in the baseline level of ALT, AST, and GGT (p<0.006 for all measures) and a downward shift in baseline CDT (p=0.002). When using standard laboratory cutoff values to determine clinically significant elevations, HCV seropositivity was significantly associated with elevations in ALT, AST, GGT (p<0.001), and with decreases in CDT (p=.002).

CONCLUSIONS

These data emphasize the importance of evaluating HCV infection and HCV risk behaviors at intake in medication trials for alcohol dependence and also raise questions regarding the use of cutoff scores for ALT, AST, GGT and CDT levels as biologic markers of alcohol use in subjects when HCV status is unknown.

A placebo-controlled randomized clinical trial of naltrexone in the context of different levels of psychosocial intervention

BACKGROUND

Naltrexone is approved for the treatment of alcohol dependence when used in conjunction with a psychosocial intervention. This study was undertaken to examine the impact of 3 types of psychosocial treatment combined with either naltrexone or placebo treatment on alcohol dependency over 24 weeks of treatment: (1) Cognitive-Behavioral Therapy (CBT) + medication clinic, (2) BRENDA (an intervention promoting pharmacotherapy) + medication clinic, and (3) a medication clinic model with limited therapeutic content.

METHODS

Two hundred and forty alcohol-dependent subjects were enrolled in a 24-week double-blind placebo-controlled study of naltrexone (100 mg/d). Subjects were also randomly assigned to 1 of 3 psychosocial interventions. All patients were assessed for alcohol use, medication adherence, and adverse events at regularly scheduled research visits.

RESULTS

There was a modest main treatment effect for the psychosocial condition favoring those subjects randomized to CBT. Intent-to-treat analyses suggested that there was no overall efficacy of naltrexone and no medication by psychosocial intervention interaction. There was a relatively low level of medication adherence (50% adhered) across conditions, and this was associated with poor outcome.

CONCLUSIONS

Results from this 24-week treatment study demonstrate the importance of the psychosocial component in the treatment of alcohol dependence. Moreover, results demonstrate a substantial association between medication adherence and treatment outcomes. The findings suggest that further research is needed to determine the appropriate use of pharmacotherapy in maximizing treatment response.

Aripiprazole effects on alcohol consumption and subjective reports in a clinical laboratory paradigm--possible influence of self-control

INTRODUCTION

There has been increasing interest in the use of medications that affect the dopamine receptor in the treatment of alcoholism. Aripiprazole has the unique pharmacology of being a partial dopamine agonist serving to stabilize brain dopamine systems in both frontal cortical and subcortical areas. As such, it might act to dampen alcohol reinforcement and craving and/or alter control over alcohol use. The current clinical laboratory study was conducted to evaluate the safety and efficacy of aripiprazole as a potential agent to alter drinking and objective effects of alcohol.

METHODS

Thirty nontreatment seeking alcoholics were enrolled in a subacute human laboratory study and received double-blind treatment with up to 15 mg of aripiprazole (n = 15) or identical placebo (n = 15) for 8 days. Tolerability and utility of aripiprazole was monitored during natural drinking over the first 6 days of medication treatment and also during a free choice limited access alcohol consumption paradigm following an initial drink of alcohol in a bar-lab setting on Day 8.

RESULTS

Aripiprazole was well tolerated and reduced drinking in nontreatment seeking alcoholics over 6 days of natural drinking--especially in those with lower self control (more impulsive). It also reduced drinks in the bar-lab after a priming drink and broke the link between priming drink induced stimulation and further drinking. During the bar-lab drinking session, there were no differences in subjective high, intoxication, or craving between subjects treated with aripiprazole or placebo.

DISCUSSION

This study joins several others in demonstrating the utility of subacute dosing laboratory paradigms for evaluating medication effects in alcoholics. Aripiprazole was well tolerated and lowered alcohol use, especially in those with lower impulse control. Further study is needed to determine the safety and utility of aripiprazole in the treatment of alcoholism and if subgroups of alcoholics are more likely to respond.

Quantitative electroencephalographic (qEEG) correlates of craving during virtual reality therapy in alcohol-dependent patients

Virtual reality (VR) is an evolving technology that is being applied to treat a wide range of medical and psychiatric diseases. A virtual reality therapy (VRT) with multisensory stimulation has been applied to patients with alcohol dependence (ADP). We hypothesized that the VRTP for alcohol dependence would reduce the craving for alcohol and increase alpha wave activity in frontal areas of individuals with ADP. Twenty ADP and eighteen ADP were exposed to a series of 10 VRTP sessions (VRTP-ADP) and cognitive behavioral therapy (nVRTP-ADP), respectively. Fifteen healthy controls were exposed to VRTP for comparing the changes of craving and EEG during all three phases of VRTP. The VRTP-ADP exhibited a greater decrease in craving after the 10th VRTP session, when compared to the nVRTP-ADP. Compared to the healthy control subjects, VRTP-ADP group showed higher magnitude of the change in craving throughout VRTP sessions. These results suggest that VRTP may be useful as an adjunct to treating alcohol dependence but may also serve as an evaluation tool to identify high-risk patients.

Effect of naltrexone and ondansetron on alcohol cue-induced activation of the ventral striatum in alcohol-dependent people

CONTEXT

Medication for the treatment of alcoholism is currently not particularly robust. Neuroimaging techniques might predict which medications could be useful in the treatment of alcohol dependence.

OBJECTIVE

To explore the effect of naltrexone, ondansetron hydrochloride, or the combination of these medications on cue-induced craving and ventral striatum activation.

DESIGN

Functional brain imaging was conducted during alcohol cue presentation.

SETTING

Participants were recruited from the general community following media advertisement. Experimental procedures were performed in the magnetic resonance imaging suite of a major training hospital and medical research institute.

PATIENTS

Ninety non-treatment-seeking alcohol-dependent (by DSM-IV criteria) and 17 social drinking (< 14 drinks per week) paid volunteers recruited through advertisements at an academic center.

INTERVENTIONS

A taste of alcohol and a series of alcohol-related pictures, neutral beverage pictures, and visual control images were provided to volunteers after 7 days of double-blind randomly assigned daily dosing with 50 mg of naltrexone (n = 23), 0.50 mg of ondansetron hydrochloride (n = 23), the combination of the 2 medications (n = 20), or matching placebos (n = 24).

MAIN OUTCOME MEASURES

Difference in brain blood oxygen level-dependent magnetic resonance when viewing alcohol pictures vs neutral beverage pictures with a particular focus on ventral striatum activity comparison across medication groups. Self-ratings of alcohol craving.

RESULTS

The combination treatment decreased craving for alcohol. Naltrexone with (P = .02) or without (P = .049) ondansetron decreased alcohol cue-induced activation of the ventral striatum. Ondansetron by itself was similar to naltrexone and the combination in the overall analysis but intermediate in a region-specific analysis.

CONCLUSIONS

Consistent with animal data that suggest that both naltrexone and ondansetron reduce alcohol-stimulated dopamine output in the ventral striatum, the current study found evidence that these medications, alone or in combination, could decrease alcohol cue-induced activation of the ventral striatum, consistent with their putative treatment efficacy.

Enhancing the validity and utility of randomized clinical trials in addictions treatment research: I. Treatment implementation and research design

PURPOSE

This paper is the first in a series that examines methods for improving the validity and utility of randomized clinical trials (RCTs) in addictions treatment research. The specific foci of this article are treatment implementation and research design.

SCOPE

We begin by considering the conditions under which the RCT provides an appropriate design choice. Sections that follow discuss methodological issues with respect to RCT structure and collaborative arrangements; treatment specification, delivery and cost; experimental design; and randomization/blinding procedures. We emphasize the importance of advance planning; treatment integrity and discriminability; treatment standardization; staff training and supervision; client compliance; maintenance of between-group equivalence across study conditions; and inclusion of appropriate comparison groups in study designs.

CONCLUSIONS

Investigators are encouraged to maximize the internal validity of RCTs, but also to consider methods for enhancing external validity. The utility of addictions RCTs for advancing theory and improving clinical practice can be enhanced by investigating underlying mechanisms of action.

What role does measuring medication compliance play in evaluating the efficacy of naltrexone?

BACKGROUND

Compliance with medication in pharmacotherapy trials of alcoholism has been shown to be equal to, or more, important than in other areas of medicine. Research has suggested that naltrexone's effectiveness can be greatly influenced by the compliance of participants in clinical trials. Presently, we compare 2 compliance measurement methods [urine riboflavin and medication event monitoring system (MEMS)] used simultaneously to evaluate naltrexone's efficacy and the impact of compliance on the size of observable treatment effects.

METHODS

One hundred and thirty-seven of 160 randomized alcoholic patients completed 12-weeks (84 days) of naltrexone or placebo and cognitive behavioral therapy (CBT) or motivational enhancement therapy (MET). Urine riboflavin was determined during study weeks 2, 6, and 12. The MEMS provided a detailed computerized record of when a participant opened their medication bottle throughout the trial. Baseline predictors of MEMS (80% openings) and urine riboflavin (>or=1,500 ng/mL by fluorimetry) compliance were examined. The effects of the treatments in the compliant participants defined by one, the other, or both methods were compared and contrasted with a previously reported intent-to-treat analysis where compliance was not taken into account.

RESULTS

Age was predictive of compliance. 105 participants were deemed compliant via urine riboflavin criteria, 87 via MEMS, and 77 when both criteria were met, with no significant differences between treatment groups. The most compliant participants showed a significant medication by therapy interaction. Those treated with naltrexone/CBT showed more abstinence days (p<0.03), less heavy drinking days (p<0.03) and less total drinks (p<0.03) than the other groups. The effect size of this interaction increased from about 0.2 in the intent-to-treat analysis, to about 0.4 to 0.5 in the compliant group analyses, with little difference between compliance measurement methods.

CONCLUSIONS

Compliance measurement does appear to influence the evaluation of the efficacy of naltrexone within the context of CBT. Treatment effect sizes approximately doubled in the most compliant individuals. Measuring compliance by either of 2 distinct methods provides approximately similar results. As compliance with naltrexone within the context of CBT has such a large impact of treatment outcome, methods of enhancing compliance during treatment should be given the utmost attention.

A systematic review of the effectiveness of naltrexone in the maintenance treatment of opioid and alcohol dependence

This systematic review summarises evidence of the effectiveness of naltrexone (NTX) and the added value of psychosocial treatment in the maintenance treatment of opioid and alcohol dependence. Studies were selected through a literature search conducted in March 2004. Seven opioid and seventeen alcohol studies were identified. When possible, meta-(regression) analyses were performed. There is lack of evidence about the effectiveness of NTX in the maintenance treatment of opioid dependence. There is evidence for the effectiveness and applicability of NTX in the management of alcohol dependence. The opioid studies combined NTX with a variety of psychosocial interventions, which plagued the evaluation of their value. Concomitant psychosocial interventions used in the alcohol studies were mainly cognitive behavioural, which seems to be more effective than NTX combined with supportive therapy. Available data do not allow firm conclusions regarding the added effect of psychosocial interventions. However, the data suggest that a combination of naltrexone with cognitive behavioural relapse prevention therapy is beneficial in alcohol dependent patients.

Complexity changes of the EEG induced by alcohol cue exposure in alcoholics and social drinkers

BACKGROUND

An understanding of the neurophysiological mechanisms underlying alcohol craving is important in the effective treatment of alcohol dependence. The aim of this study was to examine the utility of the electroencephalogram (EEG) to measure the changes in electrical brain activity of alcoholics when exposed to alcohol-specific cues.

METHODS

Fifteen adult alcoholic subjects (four women) with a mean age of 35 (SD = 4.5) and 10 healthy social drinking controls (three women) with a mean age of 34 (SD = 5.6) were recruited. Subjects were serially rated for alcohol craving after presentations of pictures of control nonalcoholic and alcohol beverages. After the picture presentation, the EEG was recorded (16,384 data points for each epoch) with eyes closed. The dimensional complexity (D2) was estimated as a measure of complexity of the EEG.

RESULTS

Alcoholic subjects exhibited a significant increase in the D2 values of the EEG in frontal (F3, F4), right posterior temporal (T6), and occipital (O1, O2) regions after viewing alcohol cues compared with viewing other beverage cues. These results indicate that more complex (or higher) cortical activity is induced over specific brain regions of alcoholic subjects by alcohol-specific cues. Changes in subscale of alcohol craving between nonalcoholic and alcohol pictures were correlated with changes in D2 values in the left frontal (F3) region in alcoholic subjects.

CONCLUSIONS

These findings suggest that, when subjects are exposed to alcohol cues, changes in the EEG complexity are induced in frontal, right posterior temporal, and occipital areas, which may be key brain structures for alcohol craving. In addition, nonlinear measures like the D2 are useful in evaluating alcohol cue-induced brain activity from the EEG.

Sertraline and cognitive behavioral therapy for depressed alcoholics: results of a placebo-controlled trial

Alcoholism and depression are common disorders that frequently co-occur in the same individual. Selective serotonin reuptake inhibitors (SSRIs) are effective in the treatment of depression and also had decreased drinking in some studies of heavy drinkers and alcoholics. The reported effect of serotonergic medications on alcohol intake in depressed alcoholics has not been consistent. Most previous studies have not investigated the use of an SSRI in the context of cognitive behavioral therapy (CBT), a known efficacious treatment of both alcoholism and depression. The study presented here was a randomized placebo-controlled 12-week trial of sertraline combined with individual CBT focused on both alcoholism relapse prevention and depressive symptoms. Subjects were 82 currently depressed, actively drinking alcohol-dependent individuals. Subjects had either primary (independent) major depression (70 subjects) or substance-induced mood disorder and at least 1 first-degree relative (parent, sibling, or child) with an affective disorder (12 subjects). Depression and alcohol consumption outcomes were measured weekly over 12 weeks. Sertraline was well tolerated and all subjects had decreases in both depression and alcohol use during the study compared with baseline. Subjects who received sertraline had fewer drinks per drinking day than subjects who received placebo, but other drinking outcomes were not different between the 2 treatment groups. Treatment with sertraline was associated with less depression at the end of treatment in female subjects compared with female subjects who received placebo. Less drinking during the study was associated with improved depression outcome. The findings in this study suggest that sertraline, compared with placebo, may provide some modest benefit in terms of drinking outcome and also may lead to improved depression in female alcohol-dependent subjects. Additionally, alcohol relapse prevention CBT, delivered according to manual guidelines with modifications that provide specific attention to depression, appeared to be of benefit to subjects, although this interpretation is limited by the design of the study.

A functional polymorphism of the mu-opioid receptor gene is associated with naltrexone response in alcohol-dependent patients

This study examined the association between two specific polymorphisms of the gene encoding the mu-opioid receptor and treatment outcomes in alcohol-dependent patients who were prescribed naltrexone or placebo. A total of 82 patients (71 of European descent) who were randomized to naltrexone and 59 who were randomized to placebo (all of European descent) in one of three randomized, placebo-controlled clinical trials of naltrexone were genotyped at the A(+118)G (Asn40Asp) and C(+17)T (Ala6Val) SNPs in the gene encoding the mu-opioid receptor (OPRM1). The association between genotype and drinking outcomes was measured over 12 weeks of treatment. In subjects of European descent, individuals with one or two copies of the Asp40 allele treated with naltrexone had significantly lower rates of relapse (p=0.044) and a longer time to return to heavy drinking (p=0.040) than those homozygous for the Asn40 allele. There were no differences in overall abstinence rates (p=0.611), nor were there differences in relapse rates or abstinence rates between the two genotype groups among those assigned to placebo. These preliminary results are consistent with prior literature demonstrating that the opioid system is involved in the reinforcing properties of alcohol and that allelic variation at OPRM1 is associated with differential response to a mu-receptor antagonist. If replicated, these results would help to identify alcohol-dependent individuals who may be most likely to respond to treatment with naltrexone.

Amlodipine reduces blood pressure and headache frequency in cocaine-dependent outpatients

Blood pressure and headache frequency were evaluated in normotensive male and female cocaine-dependent patients (N=43) participating in a placebo-controlled, double-blind trial of amlodipine for the treatment of cocaine dependence. Amlodipine produced a significant reduction in both systolic (p=0.04) and diastolic (p=0.01) blood pressures without producing dizziness or faintness. Placebo subjects had about three times the frequency of headaches compared to the amlodipine-treated subjects (p=0.004). The high frequency of headaches reported by cocaine-dependent individuals was significantly reduced by amlodipine and may reflect improved cerebrovascular tone.

Adverse outcomes in a controlled trial of pergolide for cocaine dependence

We conducted a double-blind, multiple dose comparison study of pergolide versus placebo for the treatment of cocaine dependence. In the present study, we examined patients who met criteria for cocaine dependence without comorbid alcohol dependence (N = 255). Study completion rates favored placebo (48.9%) over the low dose (33.3%) and high dose (21.5%) pergolide subjects (chi2(2) = 14.17, p < or = 0.001). Treatment effectiveness scores (TES) were significantly higher for the placebo group (31.7) than the low dose (25.2) and high dose (14.2) pergolide groups (F2,252 = 6.21, p = 0.002). There were no significant differences in side effect profiles after first dose of pergolide or placebo, or at study termination. Results of this study suggest that pergolide was not efficacious in the treatment of cocaine dependence due to reduced study participation. Caution regarding the outpatient use of pergolide in similar populations is warranted.

Posttreatment results of combining naltrexone with cognitive-behavior therapy for the treatment of alcoholism

Naltrexone, an opiate antagonist medication, has been reported to be efficacious in the treatment of alcohol dependence when added to psychosocial treatments. Although the within-treatment efficacy of naltrexone has received primary attention, there has been little published on the outcome of individuals once the medication is discontinued. Animal studies have led to concern regarding a quick rebound to heavy drinking. This report extends the data previously reported by evaluating the outcome in alcoholic subjects during the 14 weeks after a 12-week treatment with naltrexone or placebo in conjunction with cognitive behavioral therapy. Of the 131 subjects evaluated during the treatment phase, 124 (95%) had up to 14 weeks of posttreatment drinking data available for analysis. Measures of craving and blood markers of heavy drinking were also evaluated. By the end of treatment, naltrexone demonstrated significantly greater efficacy than placebo. However, once the medication was discontinued, there was a gradual increase in relapse rates, heavy drinking days, and drinks per drinking day, and fewer days of abstinence were reported. By the end of the 14-week follow-up period, although naltrexone-treated subjects were, on average, still doing better than control subjects, the effectiveness of naltrexone was no longer statistically significant. There was no evidence that naltrexone subjects had an immediate return to heavy alcohol use as suggested in animals. These data suggest that, for a number of alcoholic subjects, continued treatment with naltrexone, or perhaps psychosocial intervention, for longer than 3 months is indicated. Future research should identify which alcohol-dependent individuals may need prolonged treatment to improve treatment success in the long term.

A double-blind, placebo-controlled outpatient trial of pergolide for cocaine dependence

Results of preclinical studies suggest that pergolide, a mixed D(1)/D(2) dopamine receptor agonist, may be useful in treating cocaine dependence. To empirically investigate this possibility, we conducted a 5-year, double-blind, placebo-controlled clinical trial of two doses of pergolide (0.05 and 0.25 mg bid) in subjects with cocaine dependence and combined cocaine/alcohol dependence. Data analysis was performed on an intent to treat population (N=358) and a per protocol population (N=108) with urine drug screens (UDS) used as the main outcome measure. There were no significant effects on UDS at either pergolide dose. Pergolide had no significant effect on alcohol use in the comorbid alcohol/cocaine dependence group. Pergolide does not appear to have clinical value in the treatment of cocaine dependence or in decreasing alcohol use in cocaine-dependent individuals at the presently studied doses.

Carbohydrate-deficient transferrin in the assessment of harmful alcohol consumption: diagnostic performance and clinical significance

The last decade saw the emergence of carbohydrate-deficient transferrin (CDT) as the most promising marker for the diagnosis of alcohol abuse. Daily alcohol consumption of four beers, four glasses of wine or three standard drinks causes increased concentrations of CDT in serum. CDT is serum transferrin with a reduced content of oligosaccharides due to the detrimental effects of alcohol metabolism on the glycosylation pathway of hepatocytes and/or the increased activity of circulating glycosidases in serum. Most current CDT procedures entail separation of normal transferrin from CDT in a charged matrix-like isoelectric focusing and ion exchange chromatography, followed by detection/quantitation of CDT by a myriad of immunoassays: immunoblotting, radioimmunoassay, enzyme immunoassay and nephelometry. New CDT procedures present the advantages of improved performance, inexpensive automation and CDT results expressed as a percentage of total serum transferrin. CDT's major asset is its high specificity in well-defined populations i.e. individuals ingesting 60 g alcohol daily for at least a week.The sensitivity rates, which vary between 22% and 81%, depend on the amount of alcohol ingested, time of sample collection after the cessation of drinking, age, gender and the cut-off point chosen for analysis of tests' results. Regarding clinical applications, best outcome is achieved when the test is used to confirm a suspicion of alcohol abuse and when monitoring abstinence and relapses.The low prevalence of alcohol abuse in the general population challenges its use as a screening test.With the advent of inexpensive automation and the constant emergence of innovative, improved tests, we are seeing the rise of a new era in alcohol abuse diagnosis as affordability and education allows widespread use of CDT in a variety of settings.

Mechanisms of alcohol craving and their clinical implications

Craving for alcohol is frequently given as a reason for drinking and is often used as a surrogate measure in studies of alcoholism and its treatment. Despite this wide use, there is little consensus on what craving for alcohol means, the best way to measure it, what mechanism accounts for the urge to drink, or what is its true relationship to alcohol use. This chapter reviews theoretical and measurement issues about the possible mechanisms involved in craving for alcohol and the clinical implications of evidence supporting them. Until recently, most instruments for assessing craving assumed it was a univariate construct and usually contained only one or a few items. Several multi-item and multidimensional rating instruments have now been developed that offer the promise of more useful assessment of clinically relevant behavior. Most models of craving have assumed that a consistent and positive relationship exists between craving and drinking. The incentive sensitization model and the cognitive theory of drug use and drug urges may account better than the older models for the frequent clinical observation of a dissociation between craving and drinking. However, no single model or theory of craving accounts for the wide variation in findings reviewed here, suggesting that multiple mechanisms may be involved. A comprehensive, multidisciplinary approach is necessary to elucidate the nature of craving for alcohol and its implications for pharmacological and psychosocial treatment of alcoholism.