Varenicline potentiates alcohol-induced negative subjective responses and offsets impaired eye movements

Combination Treatment With Varenicline and Nicotine Patch on Smoking Cessation Outcomes in Heavy Drinkers at 26-Week Follow-up

PURPOSE/BACKGROUND

People who smoke cigarettes and drink alcohol heavily are less likely to quit smoking compared with those who do not drink heavily. The current study examined the effects of a 12-week treatment phase of combination varenicline and nicotine patch compared with placebo and nicotine patch on smoking cessation (primary outcome) and alcohol consumption (secondary outcome) in heavy drinking smokers at 26-week follow-up.

METHODS/PROCEDURES

Participants were daily smokers who met heavy drinking criteria. They were randomly assigned to receive either varenicline and nicotine patch (n = 61) or placebo and nicotine patch (n = 61) for 12 weeks. At week 26, self-reports of point prevalence cigarette abstinence were biochemically confirmed, and past-month alcohol drinking days and heavy drinking days were assessed.

FINDINGS/RESULTS

At week 26, smoking quit rates did not differ by treatment group (25% varenicline and 26% placebo). Relative to week 12 outcomes, week 26 quit rates significantly dropped off in the varenicline group but not in the placebo group. Alcohol drinking reductions for the whole sample that were previously observed from baseline to week 12 were sustained at week 26, although they did not differ between treatment groups.

IMPLICATIONS/CONCLUSIONS

In heavy drinking smokers, smoking cessation success was evident in a quarter of the total sample at 3 months postmedication discontinuation. At this time, quit rates were the same between those who received varenicline and nicotine patch and those who received nicotine patch alone. Future research is warranted to examine what may aid in longer-term smoking quit rates in heavy drinking smokers.

Cognitive-Enhancing Effects of Acetylcholine Receptor Agonists in Group-Housed Cynomolgus Monkeys Who Drink Ethanol

The cognitive impairments that are often observed in patients with alcohol use disorder (AUD) partially contribute to the extremely low rates of treatment initiation and adherence. Brain acetylcholine receptors (AChR) mediate and modulate cognitive and reward-related behavior, and their distribution can be altered by long-term heavy drinking. Therefore, AChRs are promising pharmacotherapeutic targets for treating the cognitive symptoms of AUD. In the present study, the procognitive efficacy of two AChR agonists, xanomeline and varenicline, were evaluated in group-housed monkeys who self-administered ethanol for more than 1 year. The muscarinic AChR antagonist scopolamine was used to disrupt performance of a serial stimulus discrimination and reversal (SDR) task designed to probe cognitive flexibility, defined as the ability to modify a previously learned behavior in response to a change in reinforcement contingencies. The ability of xanomeline and varenicline to remediate the disruptive effects of scopolamine was compared between socially dominant and subordinate monkeys, with lighter and heavier drinking histories, respectively. We hypothesized that subordinate monkeys would be more sensitive to all three drugs. Scopolamine dose-dependently impaired performance on the serial SDR task in all monkeys at doses lower than those that produced nonspecific impairments (e.g., sedation); its potency did not differ between dominant and subordinate monkeys. However, both AChR agonists were effective in remediating the scopolamine-induced deficit in subordinate monkeys but not in dominant monkeys. These findings suggest xanomeline and varenicline may be effective for enhancing cognitive flexibility in individuals with a history of heavy drinking. SIGNIFICANCE STATEMENT: Procognitive effects of two acetylcholine (ACh) receptor agonists were assessed in group-housed monkeys who had several years' experience drinking ethanol. The muscarinic ACh receptor agonist xanomeline and the nicotinic ACh receptor agonist varenicline reversed a cognitive deficit induced by the muscarinic ACh receptor antagonist scopolamine. However, this effect was observed only in lower-ranking (subordinate) monkeys and not higher-ranking (dominant monkeys). Results suggest that ACh agonists may effectively remediate alcohol-induced cognitive deficits in a subpopulation of those with alcohol use disorder.

Substitution therapy for patients with alcohol dependence: Mechanisms of action and efficacy

New approaches for the treatment of alcohol dependence (AD) may improve patient outcomes. Substitution maintenance therapy is one of the most effective treatment options for opioid and nicotine use disorders. So far, there has been little attention to substitution therapy for the treatment of AD. Here, we explain the mechanistic foundations of alcohol substitution maintenance therapy. Alcohol has many primary targets in the brain (and other organs) and the physical interaction of ethanol molecules with these specific ethanol-sensitive sites on a variety of ionotropic receptors (e.g. GABA-A, NMDA, and nicotinic acetylcholine (nACh) receptors) and ion channels provides the rationale for substitution. As such, a variety of compounds can interact with those ethanol-sensitive sites and can thus substitute for some of the effects of alcohol. For some of these compounds, alcohol discrimination studies have shown their substitution potential. Accordingly, potential substitution treatments include agonists acting at GABA receptors such as sodium oxybate, baclofen and benzodiazepines, NMDA receptor antagonists such as ketamine and memantine, or nAChRs agonists such as varenicline. All these compounds are already approved for other indications and we present clinical evidence for these drugs in the treatment of alcohol withdrawal syndrome (AWS) and in the long-term treatment of AD, and outline future steps for their acceptance as substitution treatment in AD. Finally, we discuss the substitution approach of managed alcohol programs for the most severely affected homeless populations. Results showed that sodium oxybate is probably the closest to a substitution therapy for AD and is already approved for the treatment of AWS and in the long-term treatment of AD in some countries. In conclusion, we argue that better AD treatment can be provided if substitution maintenance treatments for alcohol are implemented at a similar scale as for opioid and nicotine use disorder.

Off-label and investigational drugs in the treatment of alcohol use disorder: A critical review

Compounds known to be successful in the treatment of alcohol use disorder include the aversive agent, Disulfiram, the glutamatergic NMDA receptor antagonist, Acamprosate, and the opioid receptor antagonists, Naltrexone and Nalmefene. Although all four are effective in maintaining abstinence or reduction of alcohol consumption, only a small percentage of patients receive pharmacological treatment. In addition, many other medications have been investigated for their therapeutic potential in the treatment of alcohol use disorder. In this review we summarize and compare Baclofen, Gabapentin, Topiramate, Ondansetron, Varenicline, Aripiprazole, Quetiapine, Clozapine, Antidepressants, Lithium, Neuropeptide Y, Neuropeptide S, Corticotropin-releasing factor antagonists, Oxytocin, PF-05190457, Memantine, Ifenprodil, Samidorphan, Ondelopran, ABT-436, SSR149415, Mifepristone, Ibudilast, Citicoline, Rimonabant, Surinabant, AM4113 and Gamma-hydroxybutyrate While some have shown promising results in the treatment of alcohol use disorder, others have disappointed and should be excluded from further investigation. Here we discuss the most promising results and highlight medications that deserve further preclinical or clinical study. Effective, patient-tailored treatment will require greater understanding provided by many more preclinical and clinical studies.

Alcohol use disorder severity moderates clinical response to varenicline

BACKGROUND

In a multisite clinical trial, varenicline was effective in reducing drinking in both smoking and non-smoking patients with alcohol dependence. Because alcohol use disorder (AUD) is heterogeneous, research aimed at characterizing features associated with treatment response could advance personalized pharmacotherapy. The current study examined the utility of a multidimensional assessment of AUD severity to identify responders to varenicline treatment.

METHODS

The study utilized data from a 13-week, Phase 2, randomized, double-blind, placebo-controlled, multisite trial of varenicline in 200 alcohol-dependent patients. Four hypothesized measures of AUD severity (i.e., DSM-IV criterion count, withdrawal, craving, and alcohol-related consequences) were combined into a single severity factor. A series of multilevel models that included the severity factor were conducted to examine its effects on treatment outcomes.

RESULTS

All hypothesized indices of AUD severity loaded significantly onto a singular severity factor. Among low-severity groups, varenicline treatment significantly reduced drinking (i.e., percent heavy drinking days, drinks per day, and drinks per drinking day) and, in the lowest severity group, it improved the mental health component of quality of life more than placebo. The most severe group showed no differences between the varenicline and placebo groups on drinking or quality of life measures.

CONCLUSIONS

Treatment response to varenicline may be greater among individuals with less-severe AUD, as evidenced by both reductions in drinking outcomes and improvements in psychosocial functioning.

A Critical Review of Alcohol Administration Guidelines in Laboratory Medication Screening Research: Is It Time to Include Treatment Seekers?

Human laboratory studies play an important role in alcohol use disorder (AUD) medication development. Medications that are found to be safe and effective during human laboratory screening will then move to more expensive clinical trials in patient populations. Given the gatekeeping role of human laboratory studies in the medication development pipeline, it is critical that these studies accurately forecast how pharmacotherapies will perform under true-to-life clinical conditions. On the other hand, the design of these studies also must adhere to ethical guidelines: certain aspects of clinical reality cannot be incorporated into screening studies because doing so might place the participant at risk for harm or breach other ethical guidelines. Conventions exist that guide the resolution of these conflicting ideals. This article considers the practice of recruiting non-treatment-seeking heavy drinkers to participate in laboratory screening studies. By convention, volunteers are excluded from laboratory screening studies that involve alcohol administration if they are deemed "treatment seeking," meaning that they recently stopped drinking or are motivated to do so. Although this common practice may reduce risk to participants, findings may not accurately predict medication effects on treatment seekers. Indeed, there is empirical evidence that treatment seekers differ from nontreatment seekers in their responses to medications (Neuropsychopharmacology 2017a; 42: 1776; Am J Drug Alcohol Abuse 2017b; 43: 703; J Psychiatr Res 2006; 40: 383). Here, we argue for the importance of recruiting treatment seekers for this research due to their qualitative difference from nontreatment seekers. We argue that these individuals should be the default population in human laboratory medication screening studies. We conclude by discussing 2 case examples of medication experiments led by our research groups that involved administering medications to treatment seekers.

Eye Tracking Studies Exploring Cognitive and Affective Processes among Alcohol Drinkers: a Systematic Review and Perspectives

Acute alcohol intoxication and alcohol use disorders are characterized by a wide range of psychological and cerebral impairments, which have been widely explored using neuropsychological and neuroscientific techniques. Eye tracking has recently emerged as an innovative tool to renew this exploration, as eye movements offer complementary information on the processes underlying perceptive, attentional, memory or executive abilities. Building on this, the present systematic and critical literature review provides a comprehensive overview of eye tracking studies exploring cognitive and affective processes among alcohol drinkers. Using PRISMA guidelines, 36 papers that measured eye movements among alcohol drinkers were extracted from three databases (PsycINFO, PubMed, Scopus). They were assessed for methodological quality using a standardized procedure, and categorized based on the main cognitive function measured, namely perceptive abilities, attentional bias, executive function, emotion and prevention/intervention. Eye tracking indexes showed that alcohol-related disorders are related to: (1) a stable pattern of basic eye movement impairments, particularly during alcohol intoxication; (2) a robust attentional bias, indexed by increased dwell times for alcohol-related stimuli; (3) a reduced inhibitory control on saccadic movements; (4) an increased pupillary reactivity to visual stimuli, regardless of their emotional content; (5) a limited visual attention to prevention messages. Perspectives for future research are proposed, notably encouraging the exploration of eye movements in severe alcohol use disorders and the establishment of methodological gold standards for eye tracking measures in this field.

Design of a randomized controlled trial of smoking cessation medications for alcohol reduction among HIV-positive heavy drinkers and daily smokers in St. Petersburg, Russia

BACKGROUND

HIV, heavy drinking, and smoking are all pro-inflammatory and increase risk for coronary heart disease (CHD). Interventions that reduce alcohol use, smoking, or both in HIV-positive people could lower inflammation, CHD and death risk. Varenicline and cytisine are proven therapies for smoking cessation and may also reduce alcohol consumption. The comparative efficacy of varenicline and cytisine to reduce alcohol consumption has not been tested, nor has their comparative effectiveness been reported for smoking.

OBJECTIVE

This paper describes the protocol of the Studying Partial agonists for Ethanol and Tobacco Elimination in Russians with HIV (St PETER HIV), a four-arm parallel-group randomized controlled trial comparing effects of varenicline, cytisine, and nicotine replacement therapy (NRT).

METHODS

The study is recruiting four hundred HIV-positive heavy drinking smokers interested in cutting down on alcohol and/or tobacco in St. Petersburg, Russia. Participants are randomly assigned to receive either active varenicline + NRT placebo, varenicline placebo + active NRT, active cytisine + NRT placebo, cytisine placebo + active NRT. All participants receive evidence-based counseling for alcohol and tobacco use, one active medication, and one placebo. Outcomes are: 1) % heavy drinking days in the past month (primary study outcome at three months) and alcohol craving; 2) cigarettes per day (primary smoking outcome at 3 months) and 7-day point prevalence abstinence and; 3) inflammation, CHD risk, and mortality risk.

CONCLUSION

St PETER HIV addresses the paucity of randomized controlled trial data to guide treatment of alcohol consumption and smoking in HIV-positive heavy drinking smokers.

The role of nicotinic acetylcholine receptors in alcohol-related behaviors

Alcohol use disorder (AUD) causes an alarming economic and health burden in the United States. Unfortunately, this disease does not exist in isolation; AUD is highly comorbid with nicotine use. Results from both human and animal models demonstrate a genetic correlation between alcohol and nicotine behaviors. These data support the idea of shared genetic and neural mechanisms underlying these behaviors. Nicotine acts directly at nicotinic acetylcholine receptors (nAChR) to have its pharmacological effect. Interestingly, alcohol also acts both directly and indirectly at these receptors. Research utilizing genetically engineered rodents and pharmacological manipulations suggest a role for nAChR in several ethanol behaviors. The current manuscript collates this literature and discusses findings that implicate specific nAChR subunits in ethanol phenotypes. These data suggest future directions for targeting nAChR as novel therapeutics for AUD.

Effects of Alcohol Cue Reactivity on Subsequent Treatment Outcomes Among Treatment-Seeking Individuals with Alcohol Use Disorder: A Multisite Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Varenicline

BACKGROUND

The alcohol cue reactivity paradigm is increasingly used to screen medications for the treatment of alcohol use disorder (AUD) and other substance use disorders. Yet, its prospective association with craving and naturalistic drinking outcomes in clinical trials remains unknown. This study embedded repeated human laboratory assessments of alcohol cue reactivity within the context of a randomized controlled trial to examine the effects of varenicline tartrate (Chantix® ), a partial agonist of α4β2 nicotinic acetylcholine receptors, on alcohol craving among treatment-seeking heavy drinkers with AUD. Our main objectives were to test whether varenicline, as compared to placebo, blunts alcohol cue-elicited craving and test whether alcohol cue reactivity observed in the human laboratory predicts subsequent alcohol craving and use during the remainder of the trial.

DESIGN AND METHODS

This double-blind, randomized, 2-site study compared the effects of varenicline (up to 2 mg/d) and placebo on responses to in vivo alcohol cue and affective picture cue exposure in the human laboratory. Forty-seven volunteers (18 females, 29 males), ages 23 to 67 years (M = 43.7, SD = 11.5), were recruited from the community via advertisements to participate in a clinical trial designed to study the effects of varenicline on alcohol use. Participants were randomized to either varenicline or placebo for 6 weeks.

RESULTS

Varenicline did not attenuate cue-induced alcohol craving relative to placebo, but craving captured during the cue reactivity paradigm significantly predicted subsequent alcohol use in real-world settings during the clinical trial. Higher craving predicted heavier alcohol use.

CONCLUSIONS

Our results are among the first to show alcohol cue-induced craving captured during a human laboratory paradigm predicts drinking outcomes in the context of a clinical trial.

The Human Laboratory and Drug Development in Alcohol Use Disorder: Recent Updates

Despite a number of approved medications for alcohol use disorder (AUD), this chronic relapsing disease still produces a considerable global burden, with both health-related and financial consequences. While clinical trials are a critical step in drug development, human laboratory studies provide the field with means of screening pharmacotherapy for more nuanced aspects of AUD. Specifically, studies employing alcohol administration techniques (e.g., alcohol challenge and self-administration) are able to investigate potential drugs with respect to their ability to alter various responses to alcohol administration or alter alcohol consumption in laboratory settings. This chapter reviews methodological designs and provides updates from alcohol administration studies used to screen for potential AUD pharmacotherapy over the past decade. These recent studies have supported the efficacy of approved drugs, identified some promising novel drugs, and investigated other drugs that appear ineffective in AUD treatment. Yet, few drugs are explored using the different variants of alcohol administration methods, and using the different methods has provided inconsistent results for the same drug. Future research would aid advancement in the field by testing medication with various methodologies and refining recently developed techniques.

Alcohol Tolerance in Human Laboratory Studies for Development of Medications to treat Alcohol Use Disorder

AIMS

Human laboratory studies have contributed extensively in the research and development of novel medications to treat alcohol use disorder (AUD). Alcohol tolerance may represent one additional variable that can be utilized to expand the understanding of the AUD wide phenotypic profile and provide support to the medication development process. Tolerance is characterized as an individual's subjective response to alcohol and has been recognized as a predictor of AUD progression. Tolerance can be evaluated both by self-reported response (e.g. assessments) and objective measurements (e.g. motor impairment); as such, it represents an exploitable variable in the field of alcohol research.

METHODS

This Narrative Review focuses on the use of alcohol tolerance, specifically within alcohol laboratory studies, for medication development. It seeks to identify a research gap and a research opportunity in clinical studies to evaluate biobehavioral responses captured in order to develop medications to treat AUD.

RESULTS

Alcohol tolerance may provide additional information on the safety and tolerability of medications to treat AUD, in particular, when novel medications are co-administered with alcohol within the AUD population.

CONCLUSIONS

As such, alcohol tolerance represents an additional outcome that may be included in randomized clinical trial (RCT) protocols designed for developing AUD pharmacotherapies.

Effects of Varenicline Alone and in Combination With Low-dose Naltrexone on Alcohol-primed Smoking in Heavy-drinking Tobacco Users: A Preliminary Laboratory Study

OBJECTIVES

Heavy-drinking tobacco users are less likely to successfully quit smoking than their moderate-drinking counterparts, even when they are prescribed smoking cessation medication. One strategy for improving treatment outcomes in this subgroup of tobacco users may be to combine medication therapies to target both alcohol and tobacco use simultaneously. Adding naltrexone to frontline smoking cessation treatments may improve treatment outcomes in this group.

METHOD

This double-blind, placebo-controlled human laboratory study examined the effects of varenicline (2 mg/d) and varenicline (2 mg/d), combined with a low dose of naltrexone (25 mg/d) on alcohol-primed smoking behavior in a laboratory model of smoking relapse in heavy-drinking tobacco users (n = 30). Participants attended a laboratory session and received an alcohol challenge (target breath alcohol concentration = 0.030 g/dL). They completed a smoking delay task that assessed their ability to resist smoking followed by an ad libitum smoking phase (primary outcomes). They also provided ratings of subjective drug effects and craving, and carbon monoxide levels were measured after smoking (secondary outcomes).

RESULTS

Participants receiving varenicline monotherapy delayed smoking longer and smoked fewer cigarettes than those on placebo. Participants receiving varenicline + low-dose naltrexone did not delay smoking longer than those receiving varenicline alone. Participants in both active medication arms smoked fewer cigarettes ad libitum than those receiving placebo.

CONCLUSIONS

Varenicline can improve smoking outcomes even after an alcohol prime, supporting its use in heavy drinkers who wish to quit smoking. Findings did not support increased efficacy of combined varenicline + low-dose naltrexone relative to varenicline monotherapy.

The α3β4 nicotinic acetylcholine receptor antagonist 18-Methoxycoronaridine decreases binge-like ethanol consumption in adult C57BL/6J mice

Binge alcohol drinking is a health burden in the United States, which has an alarming economic impact. Unfortunately, medications available for alcohol abuse have low efficacy or adverse side effects, creating a need to evaluate novel therapies. Growing research suggests that 18-Methoxycoronaridine (18-MC), an α3β4 nicotinic acetylcholine receptor (nAChR) antagonist, may be effective at reducing ethanol consumption. However, its effects on binge-like ethanol consumption and other ethanol behaviors have not been examined. The present study examined the effect of α3β4 nAChRs antagonism on basal locomotor activity in male and female C57BL/6J mice. Next we tested the effect of 18-MC on binge-like ethanol consumption, ethanol-induced sedation, and ethanol metabolism. Finally, we tested the effect of α3β4 nAChRs on saccharin consumption to ensure effects were specific for ethanol. We observed that 18-MC decreased binge-like ethanol consumption without altering saccharin consumption, the sedative effects of ethanol, or ethanol metabolism. High doses of 18-MC caused locomotor sedation in C57BL/6J mice, but the effects were brief and likely did not contribute to differences in ethanol consumption. Our results support the involvement of the α3β4 nAChRs in binge-like ethanol intake, and further work should explore the use of 18-MC for treatment of alcohol use disorders.

Effects of varenicline on alcohol cue reactivity in heavy drinkers

RATIONALE

Clinical trials and human laboratory studies have established that varenicline can reduce rates of alcohol use among heavy drinkers. Less is known about the mechanisms by which varenicline has this effect on drinking behavior. Reactivity to alcohol cues is often cited as the primary cause of relapse among those being treated for alcohol use disorder, and several front-line treatments for alcohol use disorder work, at least in part, by minimizing cue-induced alcohol craving.

OBJECTIVE

The current double-blind, placebo-controlled human laboratory study tested the effects of varenicline on alcohol cue reactivity in a group of heavy-drinking adult smokers and nonsmokers.

METHODS

As part of a larger series of sequential human laboratory experiments testing the effects of varenicline on drinking outcomes, participants were assigned (between-participant) to receive either active varenicline (2 mg/day) or placebo. Following a titration period, participants (n = 77) attended a laboratory session during which they were exposed to alcohol and neutral cues using a standard cue reactivity paradigm.

RESULTS

Alcohol cue exposure increased craving for alcohol in both medication groups. However, participants receiving varenicline showed a smaller increase in alcohol craving compared to participants receiving placebo. The medication effect did not differ between smokers and nonsmokers. Among smokers, alcohol cue exposure also increased tobacco craving. Varenicline did not attenuate this effect.

CONCLUSIONS

Results support the use of varenicline for reducing alcohol use in heavy drinkers and identify a potential mechanism by which varenicline reduces drinking. Varenicline continues to show promise as a pharmacological treatment for alcohol use disorder.

Effects of varenicline on alcohol self-administration and craving in drinkers with depressive symptoms

Varenicline (VAR) is approved to aid in smoking cessation and has been shown to be effective for reducing alcohol consumption in heavy drinkers. Little is known, however, about treatment moderators that may influence efficacy. The current study reanalyzed data from a human laboratory study (Verplaetse et al., 2016) to determine whether VAR was more effective at reducing alcohol use among drinkers reporting symptoms of depression. Participants were 60 adults meeting DSM-IV criteria for alcohol use disorders ( n = 60) who were randomly assigned to receive VAR (1 mg/day, 2 mg/day) or placebo. Following 7 days of medication pretreatment, participants attended a laboratory testing session. They provided self-reported ratings of alcohol craving and performed an ad libitum alcohol consumption task after receiving a priming dose of alcohol (target blood alcohol concentration = 0.030 g/dL). Higher blood VAR plasma levels were associated with less alcohol craving and less drinking among participants with more depressive symptoms. Among participants with fewer depressive symptoms, VAR was associated with more drinking during the ad libitum drinking task. These findings show that depression symptoms may be a moderator of VAR efficacy in alcohol users and provides evidence for the role of nAChRs in depression and alcohol use.

Medications development for the treatment of alcohol use disorder: insights into the predictive value of animal and human laboratory models

Development of effective treatments for alcohol use disorder (AUD) represents an important public health goal. This review provides a summary of completed preclinical and clinical studies testing pharmacotherapies for the treatment of AUD. We discuss opportunities for improving the translation from preclinical findings to clinical trial outcomes, focusing on the validity and predictive value of animal and human laboratory models of AUD. Specifically, while preclinical studies of medications development have offered important insights into the neurobiology of the disorder and alcohol's molecular targets, limitations include the lack of standardized methods and streamlined processes whereby animal studies can readily inform human studies. Behavioral pharmacology studies provide a less expensive and valuable opportunity to assess the feasibility of a pharmacotherapy prior to initiating larger scale clinical trials by providing insights into the mechanism of the drug, which can then inform recruitment, analyses, and assessments. Summary tables are provided to illustrate the wide range of preclinical, human laboratory, and clinical studies of medications development for alcoholism. Taken together, this review highlights the challenges associated with animal paradigms, human laboratory studies, and clinical trials with the overarching goal of advancing treatment development and highlighting opportunities to bridge the gap between preclinical and clinical research.

Guidelines for biological treatment of substance use and related disorders, part 1: Alcoholism, first revision

These practice guidelines for the biological treatment of alcohol use disorders are an update of the first edition, published in 2008, which was developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBP). For this 2016 revision, we performed a systematic review (MEDLINE/PUBMED database, Cochrane Library) of all available publications pertaining to the biological treatment of alcoholism and extracted data from national guidelines. The Task Force evaluated the identified literature with respect to the strength of evidence for the efficacy of each medication and subsequently categorised it into six levels of evidence (A-F) and five levels of recommendation (1-5). Thus, the current guidelines provide a clinically and scientifically relevant, evidence-based update of our earlier recommendations. These guidelines are intended for use by clinicians and practitioners who evaluate and treat people with alcohol use disorders and are primarily concerned with the biological treatment of adults with such disorders.

A Combination of Naltrexone + Varenicline Retards the Expression of a Genetic Predisposition Toward High Alcohol Drinking

BACKGROUND

This study examined whether naltrexone (NTX) or varenicline (VAR), alone or in combination, can retard the phenotypic expression of a genetic predisposition toward high alcohol drinking in rats selectively bred for high alcohol intake when drug treatment is initiated prior to, or concomitantly with, the onset of alcohol drinking.

METHODS

Alcohol-naïve P rats were treated daily with NTX (15.0 mg/kg BW), VAR (1.0 mg/kg BW), a combination of NTX (15.0 mg/kg BW) + VAR (1.0 mg/kg BW), or vehicle (VEH) for 2 weeks prior to, or concomitantly with, their first opportunity to drink alcohol and throughout 21 days of daily 2-hour alcohol access. Drug treatment was then discontinued for 3 weeks followed by reinstatement of drug treatment for an additional 3 weeks.

RESULTS

When P rats were pretreated with drug for 2 weeks prior to onset of alcohol access, only NTX + VAR in combination blocked the acquisition of alcohol drinking in alcohol-naïve P rats. When drug treatment was initiated concomitantly with the first opportunity to drink alcohol, NTX alone, VAR alone, and NTX + VAR blocked the acquisition of alcohol drinking. Following termination of drug treatment, NTX + VAR and VAR alone continued to reduce alcohol drinking but by the end of 3 weeks without drug treatment, alcohol intake in all groups was comparable to that seen in the vehicle-treated group as the expression of a genetic predisposition toward high alcohol drinking emerged in the drug-free P rats. After 3 weeks without drug treatment, reinstatement of NTX + VAR treatment again reduced alcohol intake.

CONCLUSIONS

A combination of NTX + VAR, when administered prior to, or concomitantly with, the first opportunity to drink alcohol, blocks the acquisition of alcohol drinking during both initial access to alcohol and during a later period of alcohol access in P rats with a genetic predisposition toward high alcohol intake. The results suggest that NTX + VAR may be effective in curtailing alcohol drinking in individuals at high genetic risk of developing alcoholism.

Experimental psychopathology paradigms for alcohol use disorders: Applications for translational research

In spite of high prevalence and disease burden, scientific consensus on the etiology and treatment of Alcohol Use Disorder (AUD) has yet to be reached. The development and utilization of experimental psychopathology paradigms in the human laboratory represents a cornerstone of AUD research. In this review, we describe and critically evaluate the major experimental psychopathology paradigms developed for AUD, with an emphasis on their implications, strengths, weaknesses, and methodological considerations. Specifically we review alcohol administration, self-administration, cue-reactivity, and stress-reactivity paradigms. We also provide an introduction to the application of experimental psychopathology methods to translational research including genetics, neuroimaging, pharmacological and behavioral treatment development, and translational science. Through refining and manipulating key phenotypes of interest, these experimental paradigms have the potential to elucidate AUD etiological factors, improve the efficiency of treatment developments, and refine treatment targets thus advancing precision medicine.

Subjective Response to Alcohol as a Research Domain Criterion

BACKGROUND

Individual differences in the subjective experience of the pharmacological effects of alcohol have long been implicated in the likelihood that one will drink heavily and develop alcoholism. The theme of this conceptual review and perspective article is to synthesize the literature on subjective responses to alcohol and to set an agenda for the next generation of research in the area. Specifically, we contend that in order for subjective response to alcohol to play a prominent role in alcoholism research, it is critical that it be studied as a multimodal phenotype.

METHODS

First, we review the human research on subjective response to alcohol measured under controlled laboratory conditions and draw recommendations for the application of these findings to understanding alcoholism neurobiology in humans. Second, we highlight multimodal approaches, including studies of the genetic and neural substrates of individual differences in subjective response to alcohol. Third, we review treatment implications with a focus on subjective response to alcohol as an intervention target. Upon review of the research on subjective response to alcohol across levels of analyses, we provide recommendations for leveraging these phenotypes in a systematic and methodologically rigorous fashion that can address central questions about alcoholism etiology, disease progression, and personalized treatment.

DISCUSSION

The approach recommended herein is largely consistent with the Research Domain Criteria (RDoC) initiative across the National Institute of Mental Health. The defining feature of such domains is that they inform behavior yet be amenable to examination through multiple units of analysis, such as molecular, genetic, circuit-level, and behavioral measurements. To that end, we contend that subjective response to alcohol represents a behaviorally and biologically plausible phenotype upon which to build using the RDoC framework for understanding alcohol use disorder.

Effect of Varenicline Combined with High-Dose Alcohol on Craving, Subjective Intoxication, Perceptual Motor Response, and Executive Cognitive Function in Adults with Alcohol Use Disorders: Preliminary Findings

BACKGROUND

Varenicline has been found to decrease alcohol-motivated behaviors. Recent warnings regarding aversive events associated with varenicline used in conjunction with alcohol warrant further investigation into the safety of the drug when combined with alcohol. The purpose of this preliminary investigation was to examine the effect of combining varenicline with a high, fixed dose of alcohol on subjective reactivity and cognitive function in adults with alcohol use disorders (AUDs).

METHODS

This double-blind, placebo-controlled preliminary investigation examined the effects of varenicline (0, 1, 2 mg/d) on subjective reactivity, cognition, perceptual motor function, and physiologic reactivity to a fixed dose of alcohol (vs. nonalcohol control beverage) using an established laboratory paradigm in smokers and nonsmokers meeting criteria for AUDs (n = 44). All participants had completed a parent varenicline study evaluating alcohol self-administration. Each subject completed 2 fixed-dose laboratory sessions assessing reactivity to a high-dose alcohol (0.08 g/dl) or a nonalcoholic control beverage, order counterbalanced.

RESULTS

Varenicline attenuated alcohol-related increases in subjective intoxication and alcohol-related decreases in executive cognitive function. At baseline, varenicline reduced alcohol craving and diastolic blood pressure, and increased associative learning, working memory, and perceptual motor function. Varenicline produced nonspecific effects on diastolic blood pressure and heart rate. Overall, there were few differences in effects between 1 and 2 mg/d varenicline versus placebo.

CONCLUSIONS

These preliminary results continue to support the safety and use of varenicline in combination with alcohol in individuals meeting criteria for AUDs.

Current insights into the mechanisms and development of treatments for heavy drinking cigarette smokers

There is a strong association between cigarette smoking and alcohol use at the epidemiological, behavioral, and molecular levels, and this co-use creates substantial impediments to smoking cessation among smokers who are also heavy drinkers. Compared with individuals who only smoke, those who both drink and smoke heavily experience more severe health consequences and have greater difficulty in quitting smoking. During smoking abstinence, greater alcohol use is associated with decreased odds of smoking cessation, and smokers are substantially more likely to experience a smoking lapse during drinking episodes. As heavy drinking smokers are less responsive to the currently available pharmacological treatments, this subgroup of high-risk substance users possesses a unique clinical profile and treatment needs. Thus, treatment development for heavy drinking smokers represents a significant and understudied research area within the field of smoking cessation. This review will briefly describe findings from epidemiological, behavioral, and molecular studies illustrating alcohol and tobacco co-use and identify how the behavioral and neurobiological mechanisms underlying the interaction of alcohol and nicotine may inform the development of targeted treatments for this unique population of smokers.

Varenicline decreases nicotine but not alcohol self-administration in genetically selected Marchigian Sardinian alcohol-preferring (msP) rats

BACKGROUND

Alcohol and nicotine are largely co-abused. Here, we investigated whether concurrent exposure to both addictive drugs influences each other's consumption and whether varenicline attenuates alcohol consumption in the presence of nicotine.

METHODS

Marchigian Sardinian alcohol-preferring (msP) rats trained to simultaneously self-administer oral alcohol (10% v/v) and intravenous nicotine (30μg/kg/inf) were used. Additional groups of rats were trained to self-administer either alcohol or nicotine. Further, msP rats were also trained to self-administer nicotine followed by 22-h/day access to alcohol and water in a two bottle free choice paradigm or water alone. The effects of varenicline (0.0, 0.3, 1.0, 3.0mg/kg, p.o.) on alcohol and nicotine consumption were tested.

RESULTS

In a self-administration paradigm, msP rats showed a significantly high level of alcohol and nicotine intake when the drugs were administered alone. However, when access to both drugs occurred concomitantly, the number of nicotine infusions self-administered was significantly decreased. Nicotine self-administration was markedly reduced by varenicline regardless of whether it was self-administered alone or concurrently with alcohol. In a two bottle choice test, varenicline significantly decreased nicotine self-administration but had no influence on alcohol consumption.

CONCLUSION

Varenicline is highly efficacious in decreasing nicotine self-administration either alone or in combination with alcohol. However, varenicline failed to influence both operant responding for alcohol and home-cage alcohol drinking in msP animals. Taken together, our findings suggest that the effects of varenicline could be specific to nicotine under conditions where excessive alcohol drinking is facilitated by genetic factors as in msP rats.

The role of varenicline on alcohol-primed self-administration and seeking behavior in rats

RATIONALE

Varenicline, a smoking-cessation agent, may be useful in treating alcohol use disorders. An important consideration when studying factors that influence drinking/relapse is influence of the pharmacological effects of alcohol on these behaviors. Pre-exposure to alcohol (priming) can increase craving, drinking, and seeking behaviors.

OBJECTIVES

The primary goal of this work was to determine the effects of varenicline on alcohol-primed self-administration and seeking behavior in male Long-Evans rats.

METHODS

First, we assessed whether varenicline (0, 0.3, 1, 3 mg/kg, IP) has alcohol-like discriminative stimulus effects and whether varenicline alters sensitivity to alcohol in rats trained to discriminate a moderate alcohol dose (1 g/kg, IG) vs. water. Second, animals trained to self-administer alcohol underwent assessments to test the effects of: (i) varenicline (0, 0.3, 1, 3 mg/kg, IP) on self-administration, (ii) alcohol priming (0, 0.3, 1 g/kg, IG) on self-administration and seeking behavior, and (iii) varenicline (1 mg/kg) in combination with alcohol priming (1 g/kg) on these behaviors.

RESULTS

Varenicline did not substitute for alcohol but disrupted the expression of sensitivity to alcohol. Varenicline decreased self-administration but only at a motor-impairing dose (3 mg/kg). Alcohol priming decreased self-administration and seeking behavior. Varenicline (1 mg/kg) blocked this effect under self-administration conditions, but not seeking conditions, which effectively resulted in increased alcohol intake.

CONCLUSIONS

These findings suggest the importance of further behavioral and mechanistic studies to evaluate the use of varenicline in treating alcohol use disorders and its potential impact on drinking patterns in smokers using varenicline as a smoking-cessation aid.

Subjective response as a consideration in the pharmacogenetics of alcoholism treatment

Currently available pharmacological treatments for alcoholism have modest efficacy and high individual variability in treatment outcomes, both of which have been partially attributed to genetic factors. One path to reducing the variability and improving the efficacy associated with these pharmacotherapies may be to identify overlapping genetic contributions to individual differences in both subjective responses to alcohol and alcoholism pharmacotherapy outcomes. As acute subjective response to alcohol is highly predictive of future alcohol related problems, identifying such shared genetic mechanisms may inform the development of personalized treatments that can effectively target converging pathophysiological mechanisms that convey risk for alcoholism. The focus of this review is to revisit the association between subjective response to alcohol and the etiology of alcoholism while also describing genetic contributions to this relationship, discuss potential pharmacogenetic approaches to target subjective response to alcohol in order to improve the treatment of alcoholism and examine conceptual and methodological issues associated with these topics, and outline future approaches to overcome these challenges.

Pharmacological Options for Smoking Cessation in Heavy-Drinking Smokers

There is a high prevalence of comorbid tobacco use and alcohol use disorder (AUD), affecting more than 6 million people in the US. Globally, tobacco and alcohol use rank fourth and fifth, respectively, for disability-adjusted life-years lost. Levels of alcohol use are higher in smokers than nonsmokers, and the prevalence of smoking is higher in heavy drinkers compared with nondrinkers. This relationship is driven by many different factors, including genetics, neurobiological mechanisms, conditioning processes, and psychosocial influences. Although this unique population tends to experience more negative health consequences, more severe AUD, and poorer response to treatment than those with either AUD or tobacco use disorder alone, there are currently no available treatment protocols tailored to this comorbid condition. In this review, we provide a comprehensive review of ongoing clinical research into smoking cessation options for heavy-drinking smokers (HDS) through an evaluation of the effect of promising novel pharmacotherapies as well as combination therapies, including varenicline, naltrexone, the combination of varenicline and naltrexone, and the combination of naltrexone and nicotine replacement therapy (NRT). These treatments are considered in light of the standard of care for smoking cessation, and seek to improve upon the available guidelines for this sizeable subgroup of smokers, namely those smokers who drink heavily.

Effects of varenicline on ethanol-induced conditioned place preference, locomotor stimulation, and sensitization

BACKGROUND

Varenicline, a partial nicotinic acetylcholine receptor (nAChR) agonist, is a promising new drug for the treatment of alcohol (ethanol [EtOH]) dependence. Varenicline has been approved by the Food and Drug Administration as a smoking cessation therapeutic and has also been found to reduce EtOH consumption in humans and animal models of alcohol use. These studies examined the hypotheses that varenicline attenuates the stimulant and sensitizing effects of EtOH and reduces the motivational effects of EtOH-associated cues. The goal was to determine whether these effects of varenicline contribute to its pharmacotherapeutic effects for alcohol dependence. In addition, effects of varenicline on acute stimulation and/or on the acquisition of sensitization would suggest a role for nAChR involvement in these effects of EtOH.

METHODS

Dose-dependent effects of varenicline on the expression of EtOH-induced conditioned place preference (CPP), locomotor activation, and behavioral sensitization were examined. These measures model motivational effects of EtOH-associated cues, euphoric or stimulatory effects of EtOH, and EtOH-induced neuroadaptation. All studies used DBA/2J mice, an inbred strain with high sensitivity to these EtOH-related effects.

RESULTS

Varenicline did not significantly attenuate the expression of EtOH-induced CPP. Varenicline reduced locomotor activity and had the most pronounced effect in the presence of EtOH, with the largest effect on acute EtOH-induced locomotor stimulation and a trend for varenicline to attenuate the expression of EtOH-induced sensitization.

CONCLUSIONS

Because varenicline did not attenuate the expression of EtOH-induced CPP, it may not be effective at reducing the motivational effects of EtOH-associated cues. This outcome suggests that reductions in the motivational effects of EtOH-associated cues may not be involved in how varenicline reduces EtOH consumption. However, varenicline did have effects on locomotor behavior and significantly attenuated acute EtOH-induced locomotor stimulation. In humans who drink while taking varenicline, it might similarly reduce stimulant responses and have an impact on continued drinking. General sedative effects in such individuals should be carefully considered.

Varenicline, low dose naltrexone, and their combination for heavy-drinking smokers: human laboratory findings

RATIONALE

Heavy-drinking smokers constitute a sizeable and hard-to-treat subgroup of smokers, for whom tailored smoking cessation therapies are not yet available.

OBJECTIVES

The present study used a double-blind, randomized, 2 × 2 medication design, testing varenicline alone (VAR; 1 mg twice daily), low dose naltrexone alone (L-NTX; 25 mg once daily), varenicline plus naltrexone, and placebo for effects on cigarette craving and subjective response to alcohol and cigarettes in a sample (n = 130) of heavy-drinking daily smokers (≥10 cigarettes/day).

METHODS

All participants were tested after a 9-day titration period designed to reach a steady state on the target medication. Testing was completed at 12 h of nicotine abstinence, after consuming a standard dose of alcohol (target breath alcohol concentration = 0.06 g/dl) and after smoking the first cigarette of the day.

RESULTS

The combination of VAR + L-NTX was superior to placebo, and at times superior to monotherapy, in attenuating cigarette craving, cigarette and alcohol "high," and in reducing ad-lib consumption of both cigarettes and alcohol during the 9-day medication titration period.

CONCLUSIONS

These preliminary findings indicate that clinical studies of the combination of VAR + L-NTX for heavy drinkers trying to quit smoking are warranted and may ultimately improve clinical care for this sizeable and treatment-resistant subgroup of smokers.

Varenicline effects on drinking, craving and neural reward processing among non-treatment-seeking alcohol-dependent individuals

RATIONALE

The α4β2 nicotinic acetylcholine receptor partial agonist varenicline has been reported to reduce drinking among both heavy-drinking smokers and primary alcoholics, and this effect may be related to varenicline-mediated reduction of alcohol craving. Among smokers, varenicline has been reported to modulate cigarette cue-elicited brain activation in several reward-related areas.

OBJECTIVES

This pilot study tested varenicline's effects on drinking, alcohol craving, and alcohol cue-elicited activation of reward-related brain areas among non-treatment-seeking alcohol-dependent individuals.

METHODS

Thirty-five such individuals (mean age = 30, 57 % male, 76 % heavy drinking days in the past month, 15 smokers) were randomized to either varenicline (titrated to 2 mg) or placebo for 14 days, and were administered an alcohol cue reactivity fMRI task on day 14. A priori regions of interest (ROIs) were bilateral and medial orbitofrontal cortex (OFC), right ventral striatum (VS), and medial prefrontal cortex (mPFC).

RESULTS

Despite good medication adherence, varenicline did not reduce heavy drinking days or other drinking parameters. It did, however, increase self-reported control over alcohol-related thoughts and reduced cue-elicited activation bilaterally in the OFC, but not in other brain areas.

CONCLUSIONS

These data indicate that varenicline reduces alcohol craving and some of the neural substrates of alcohol cue reactivity. However, varenicline effects on drinking mediated by cue-elicited brain activation and craving might be best observed among treatment-seekers motivated to reduce their alcohol consumption.

Varenicline in the treatment of alcohol use disorders

OBJECTIVE

To summarize the efficacy and safety data for the use of varenicline in the treatment of alcohol use disorders.

DATA SOURCES

A literature search was conducted in PubMed, International Pharmaceutical Abstracts, and Cochrane Library (through May 2014). Key search terms included varenicline, alcohol, alcohol dependence, alcoholism, ethanol, and nicotinic acetylcholine receptor. Additional references were identified from literature citations.

STUDY SELECTION AND DATA EXTRACTION

Results were limited to clinical trials and case reports that discussed either the use of varenicline in alcohol drinking patients or adverse effects experienced with its use. Only English language studies in humans were reviewed.

DATA SYNTHESIS

In all, 7 randomized, placebo-controlled clinical trials and 1 open-label study were identified that evaluated the impact of varenicline on various drinking-related end points. The studies were conducted in patients dependent on alcohol (n=4), non-alcohol-dependent patients (n=3), and patients with a history of alcohol dependence but who had been abstinent for at least 6 months (n=1). The majority of the studies classified their participants as heavy drinkers; however, this definition varied across studies. Most studies included smokers, but 2 trials included both smokers and nonsmokers.

CONCLUSIONS

Evidence supports the use of varenicline for the reduction of alcohol craving as well as for the reduction of overall alcohol consumption in patients with alcohol use disorders. However, it is not likely to improve abstinence rates. Although most of the data were derived from patients with concurrent nicotine dependence, the effects of varenicline appear to occur independent of baseline smoking status.

The effects of varenicline on alcohol seeking and self-administration in baboons

BACKGROUND

Nicotinic acetylcholine receptors (nAChRs) may play a critical role in alcohol reinforcement and consumption. The effects of varenicline, an nAChR partial agonist, on alcohol seeking and self-administration responses were evaluated in 2 groups of baboons trained under a 3-component chained schedule of reinforcement (CSR).

METHODS

Alcohol (4% w/v; n = 4; alcohol group) or a preferred nonalcoholic beverage (n = 4; control group) was available for self-administration only in component 3 of the CSR. Responses in component 2, required to gain access to alcohol, provided indices of seeking behavior. Varenicline (0.032 to 0.32 mg/kg; 0.32 mg/kg twice daily [BID]) and vehicle were administered before CSR sessions subchronically (5 consecutive days). Higher doses (0.56, 1.0 mg/kg) were attempted, but discontinued due to adverse effects.

RESULTS

Subchronic varenicline administration significantly (p < 0.05) decreased the seeking response rate and increased the time to complete the response requirement to gain access to the daily supply of alcohol at the higher doses (0.32 mg/kg, 0.32 mg/kg BID dosing) in the alcohol group compared with the control group. Mean number of drinks was significantly decreased (p < 0.05), but effects did not differ between groups. The pattern of drinking was characterized by a high rate during an initial bout. Number of drinks during and duration of the initial bout were significantly decreased in the alcohol group, compared with the control group, at 0.32 mg/kg (p < 0.05).

CONCLUSIONS

Varenicline may be clinically useful for reducing alcohol-seeking behaviors prior to alcohol exposure. Given the modest effects on drinking itself, varenicline may be better suited as a treatment in combination with a pharmacotherapy that significantly reduces alcohol consumption.

The effects of varenicline on stress-induced and cue-induced craving for cigarettes

BACKGROUND

Varenicline is a partial agonist of the α4β2 nicotinic acetylcholine receptor approved by the FDA for the treatment of nicotine dependence. While the clinical efficacy of varenicline for smoking cessation is well-supported, its biobehavioral mechanisms of action remain poorly understood. This randomized, crossover, placebo-controlled, human laboratory study combines guided imagery stress exposure with in vivo presentation of cigarette cues to test the effects of varenicline on stress-induced and cue-induced craving for cigarettes.

METHOD

A total of 40 (13 females) daily smokers (≥10 cigarettes per day) completed a guided imagery exposure (stress and neutral) followed by the presentation of cigarette cues at the target dose of varenicline (1mg twice per day) and on matched placebo.

RESULTS

Multilevel regression models revealed a significant main effect of varenicline (p<.01) such that it reduced cigarette craving across the experimental paradigm, compared to placebo. There was also a significant medication×stress×trial interaction indicating that varenicline attenuated cue induced craving following neutral imagery but not when cues were preceded by stress induction (i.e., stress+cues).

CONCLUSIONS

These results elucidate the biobehavioral effects of varenicline for nicotine dependence and suggest that varenicline-induced amelioration of cigarette craving is unique to tonic craving and cue-induced craving following neutral imagery but does not extend to the combination of stress plus cues.

Neuronal nicotinic acetylcholine receptors: common molecular substrates of nicotine and alcohol dependence

Alcohol and nicotine are often co-abused. As many as 80-95% of alcoholics are also smokers, suggesting that ethanol and nicotine, the primary addictive component of tobacco smoke, may functionally interact in the central nervous system and/or share a common mechanism of action. While nicotine initiates dependence by binding to and activating neuronal nicotinic acetylcholine receptors (nAChRs), ligand-gated cation channels normally activated by endogenous acetylcholine (ACh), ethanol is much less specific with the ability to modulate multiple gene products including those encoding voltage-gated ion channels, and excitatory/inhibitory neurotransmitter receptors. However, emerging data indicate that ethanol interacts with nAChRs, both directly and indirectly, in the mesocorticolimbic dopaminergic (DAergic) reward circuitry to affect brain reward systems. Like nicotine, ethanol activates DAergic neurons of the ventral tegmental area (VTA) which project to the nucleus accumbens (NAc). Blockade of VTA nAChRs reduces ethanol-mediated activation of DAergic neurons, NAc DA release, consumption, and operant responding for ethanol in rodents. Thus, ethanol may increase ACh release into the VTA driving activation of DAergic neurons through nAChRs. In addition, ethanol potentiates distinct nAChR subtype responses to ACh and nicotine in vitro and in DAergic neurons. The smoking cessation therapeutic and nAChR partial agonist, varenicline, reduces alcohol consumption in heavy drinking smokers and rodent models of alcohol consumption. Finally, single nucleotide polymorphisms in nAChR subunit genes are associated with alcohol dependence phenotypes and smoking behaviors in human populations. Together, results from pre-clinical, clinical, and genetic studies indicate that nAChRs may have an inherent role in the abusive properties of ethanol, as well as in nicotine and alcohol co-dependence.

Longitudinal associations between smoking cessation medications and alcohol consumption among smokers in the International Tobacco Control Four Country survey

BACKGROUND

Available evidence suggests that quitting smoking does not alter alcohol consumption. However, smoking cessation medications may have a direct impact on alcohol consumption independent of any effects on smoking cessation. Using an international longitudinal epidemiological sample of smokers, we evaluated whether smoking cessation medications altered alcohol consumption independent of quitting smoking.

METHODS

Longitudinal data were analyzed from the International Tobacco Control Four Country (ITC-4) Survey between 2007 and 2008, a telephone survey of nationally representative samples of smokers from the United Kingdom, Australia, Canada, and the United States (n = 4,995). Quantity and frequency of alcohol consumption, use of smoking cessation medications (varenicline, nicotine replacement [NRT], and no medications), and smoking behavior were assessed across 2 yearly waves. Controlling for baseline drinking and changes in smoking status, we evaluated whether smoking cessation medications were associated with reduced alcohol consumption.

RESULTS

Varenicline was associated with a reduced likelihood of any drinking compared with nicotine replacement (OR = 0.56; 95% CI = 0.34 to 0.94), and consuming alcohol once a month or more compared to nicotine replacement (OR = 0.43; 95% CI = 0.27 to 0.69) or no medication (OR = 0.63; 95% CI = 0.41 to 0.99). Nicotine replacement was associated with an increased likelihood of consuming alcohol once a month or more compared to no medication (OR = 1.14; 95% CI = 1.03 to 1.25). Smoking cessation medications were not associated with more frequent drinking (once a week or more) or typical quantity consumed per episode. Medication effects on drinking frequency were independent of smoking cessation.

CONCLUSIONS

This epidemiological investigation demonstrated that varenicline was associated with a reduced frequency of alcohol consumption. Continued work should clarify under what conditions nicotine replacement therapies may increase or decrease patterns of alcohol consumption.

How can we use our knowledge of alcohol-tobacco interactions to reduce alcohol use?

Currently, 8.5% of the US population meets criteria for alcohol use disorders, with a total cost to the US economy estimated at $234 billion per year. Alcohol and tobacco use share a high degree of comorbidity and interact across many levels of analysis. This review begins by highlighting alcohol and tobacco comorbidity and presenting evidence that tobacco increases the risk for alcohol misuse and likely has a causal role in this relationship. We then discuss how knowledge of alcohol and tobacco interactions can be used to reduce alcohol use, focusing on whether (a) smoking status can be used as a clinical indicator for alcohol misuse, (b) tobacco policies reduce alcohol use, and (c) nicotinic-based medications can be used to treat alcohol use disorders.