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

Efficacy of Varenicline in the Treatment of Alcohol Dependence: An Updated Meta-Analysis and Meta-Regression

BACKGROUND

Although varenicline has been used for alcohol dependence (AD) treatment, its efficacy for this condition remains controversial.

AIMS

This systematic review and meta-analysis of randomized controlled trials (RCTs) assesses the efficacy and safety of varenicline in patients with AD.

METHODS

PubMed, Cochrane Library, ScienceDirect, Web of Science, and ThaiLis were systematically searched. RCTs investigating the efficacy and safety of varenicline in patients with AD were included. Study selection, data extraction, and quality assessment were independently performed by two authors. The Jadad score and Cochrane risk of bias were used to assess the quality of the included studies. Heterogeneity was assessed using I² and chi-squared tests.

RESULTS

Twenty-two high-quality RCTs on 1421 participants were included. Varenicline significantly reduced alcohol-related outcomes compared with placebo based on percentage of abstinent days (standardized mean difference [SMD] 4.20 days; 95% confidence interval [CI]: 0.21, 8.19; p = 0.04), drinks per day (SMD -0.23 drinks; 95% CI: -0.43, -0.04; p = 0.02), drinks per drinking day (SMD -0.24 drinks; 95% CI: -0.44, -0.05; p = 0.01), craving assessed using the Penn alcohol craving scale (SMD -0.35; 95% CI: -0.59, -0.12; p = 0.003), and craving assessed using the alcohol urge questionnaire (SMD -1.41; 95% CI: -2.12, -0.71; p < 0.0001). However, there were no significant effects on abstinence rate, percentage of drinking days, percentage of heavy drinking days, alcohol intoxication, or drug compliance. Serious side effects were not observed in the varenicline or placebo groups.

CONCLUSION

Our results indicated that AD patients treated with varenicline showed improvement in percentage of very heavy drinking days, percentage of abstinent days, drinks per day, drinks per drinking day, and craving. However, well-designed RCTs with a large sample size and long duration on varenicline treatment in AD remain warranted to confirm our findings.

Modeling ability to resist alcohol in the human laboratory: A pilot study

BACKGROUND

Roughly half of patients with alcohol use disorder prefer non-abstinence based approaches to treatment. However, only individuals who can limit their alcohol use after low-risk consumption are most likely to benefit from these approaches. This pilot study developed a laboratory-based intravenous alcohol self-administration paradigm to determine the characteristics of individuals who could successfully resist consuming alcohol after an initial exposure.

METHODS

Seventeen non-treatment seeking heavy drinkers completed two versions of an intravenous alcohol self-administration paradigm designed to assess impaired control over alcohol use. In the paradigm, participants received a priming dose of alcohol and then entered a 120-min resist phase, in which they received monetary rewards if they resisted self-administering alcohol. We used Cox proportional hazards regression to determine the impact of craving and Impaired Control Scale scores on rate of lapse.

RESULTS

64.7% of participants across both versions of the paradigm were unable to resist alcohol for the duration of the session. Craving at baseline (HR = 1.07, 95% CI 1.01-1.13, p = 0.02) and following priming (HR = 1.08, 95% CI 1.02-1.15, p = 0.01) were associated with rate of lapse. Individuals who lapsed endorsed greater attempts to control their drinking over the prior six months compared to individuals who resisted.

CONCLUSIONS

This study provides preliminary evidence that craving may be predictive of risk of lapse in individuals who are trying to limit alcohol intake after consuming a small initial amount of alcohol. Future studies should test this paradigm in a larger and more diverse sample.

Effects of varenicline and bupropion on laboratory smoking outcomes: Meta-analysis of randomized, placebo-controlled human laboratory studies

Human laboratory studies are widely used to evaluate behavioural mechanisms of pharmacotherapy effects. Results from human laboratory studies examining smoking cessation pharmacotherapies have not been examined in aggregate. The current meta-analysis aimed to synthesize data from randomized, placebo-controlled human laboratory studies on the effects of non-nicotine pharmacotherapies on outcomes relevant for smoking cessation. Literature searches identified 15 human laboratory studies of varenicline (n = 697) and 9 studies of bupropion (n = 313) with sufficient data for inclusion. Studies involved acute or subacute pharmacotherapy treatment with administration durations ranging from a single dose to 8 weeks. Primary outcomes examined were craving, withdrawal and behavioural indices of smoking. Varenicline significantly reduced craving (Hedge's g = -0.36[-0.54,-0.17], p < 0.001), withdrawal (g = -0.25[-0.41,-0.09], p = 0.003) and behavioural indices of smoking (g = -0.36[-0.63,-0.08], p = 0.01) relative to placebo. In contrast, results were inconclusive regarding bupropion's effects on craving (g = -0.13[-0.32,0.05], p = 0.15), withdrawal (g = -0.15[-0.44,0.14], p = 0.31) and behavioural indices of smoking (g = -0.05[-0.35,0.24], p = 0.73) relative to placebo. Findings provide meta-analytic support that short-term varenicline treatment decreases craving, withdrawal symptoms and smoking behaviour under controlled laboratory conditions. However, findings also suggest the ability of human laboratory paradigms to detect pharmacotherapy effects may differ by treatment type. Pharmacotherapy discovery and evaluation efforts utilizing human laboratory methods should aim to align study designs and laboratory procedures with presumed therapeutic mechanisms when possible.

Endogenous Opiates and Behavior: 2018

This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).

Searching for Personalized Medicine for Binge Drinking Smokers: Smoking Cessation Using Varenicline, Nicotine Patch, or Combination Nicotine Replacement Therapy

OBJECTIVE

Heavy drinking is common among smokers and is associated with especially poor health outcomes. Varenicline may affect mechanisms and clinical outcomes that are relevant for both smoking cessation and alcohol use. The current study examines whether varenicline, relative to nicotine replacement therapy, yields better smoking cessation outcomes among binge drinking smokers.

METHOD

Secondary data analyses of a comparative effectiveness randomized controlled trial of three smoking cessation pharmacotherapies (12 weeks of varenicline, nicotine patch, or nicotine patch and lozenge) paired with six counseling sessions were conducted. Adult daily cigarette smokers (N = 1,078, 52% female) reported patterns of alcohol use, cigarette craving, and alcohol-related cigarette craving at baseline and over 4 weeks after quitting. Smoking cessation outcome was 7-day biochemically confirmed point-prevalence abstinence.

RESULTS

Binge drinkers had higher relapse rates than moderate drinkers at 4-week post-target quit day but not at the end of treatment or long-term follow up (12 and 26 weeks). Varenicline did not yield superior smoking cessation outcomes among binge drinkers, nor did it affect alcohol use early in the quit attempt. Varenicline did produce relatively large reductions in alcohol-related cigarette craving and overall cigarette craving during the first 4 weeks after quitting.

CONCLUSIONS

Varenicline did not yield higher smoking abstinence rates or reduce alcohol use among binge drinkers. Varenicline did reduce alcohol-related cigarette craving but this did not translate to meaningful differences in smoking abstinence. Varenicline's effects on smoking abstinence do not appear to vary significantly as a function of drinking status.

Probing the Manipulated Neurochemical Drive in Alcohol Addiction and Novel Therapeutic Advancements

Alcohol addiction is one of the highly prevalent neurological disorders and a major threat to public health in the 21st century. Alcohol addiction affects people from all age groups and often leads to other serious comorbidities. The pathophysiology of alcohol addiction involves imbalance between the excitatory and inhibitory neurotransmitters in the brain. These changes occur in various regions of the brain including reward circuit such as the ventral tegmental area (VTA), nucleus accumbens (NAc), and prefrontal cortex. In this review, we have discussed several neurochemical circuitries which get manipulated and maladapted during alcohol addiction. To date there is no effective therapeutic intervention in clinics devoid of side effects that can successfully treat the patients suffering from alcohol addiction. Understanding the neurobiological intricacies of alcohol addiction is critical for the development of novel anti-addiction therapeutics. Apart from this, we have also discussed the recent therapeutic milestones for the management of alcohol addiction including vasopressin receptors, corticotrophin-releasing factor, GABA receptors, glucocorticoid receptors, brain stimulation and mindfulness-oriented recovery enhancement.

The ironic effects of stigmatizing smoking: combining stereotype threat theory with behavioral pharmacology

AIMS

Public service announcements often create media messages intended to stigmatize negative behaviors to reduce and prevent these behaviors. Drawing on social and cognitive psychology, we hypothesize that stigmatizing messages can create stereotype threat would be associated with shorter latency to first cigarette in the laboratory compared to the control condition.

DESIGN

A double-blind, randomized, controlled trial in which participants completed two smoking lapse tasks, one at baseline and one post-intervention/control.

SETTING

An experimental psychopharmacology laboratory in the western United States.

PARTICIPANTS

A community sample of non-treatment-seeking daily smokers (n = 77) received either a stereotype threat (n = 39) or neutral/control (n = 38) message.

INTERVENTION

Participants received either a stereotype threat message that stigmatized smoking or a control message.

MEASUREMENTS

The primary outcome measure was participants' ability to delay smoking during the smoking lapse task in the experimental session FINDINGS: The difference in delay time during the experimental session at the point where 50% of each group had smoked was 3 minutes. Cox proportional hazard models revealed that participants in the stereotype threat group were significantly less able to delay initiating smoking compared to the control group (hazard ratio = 0.504, P = 0.010, 95% confidence interval = 0.30, 0.85), after controlling for baseline latency to smoke.

CONCLUSIONS

Messages that elicit negative stereotypes of smokers operated as 'smoking-promoting messages' in the context of our controlled laboratory investigation.

Naltrexone and alcohol effects on craving for cigarettes in heavy drinking smokers

Naltrexone has been extensively studied for the treatment of alcohol use disorder. However, less is known about the effects of naltrexone on smoking outcomes in the context of alcohol use among East Asian individuals who have been suggested to differ in response to alcohol and to naltrexone. The present study is a secondary analysis that used a double-blind placebo-controlled design (n = 31) to examine the (a) effects of alcohol on basal craving for cigarettes, (b) effects of naltrexone on cigarette craving and alcohol craving during alcohol administration, and (c) relationship between craving for alcohol and cigarettes. Heavy drinking smokers of East Asian descent completed two counterbalanced intravenous alcohol administration sessions, one after taking naltrexone (50 mg) for five days and one after taking a placebo for five days. Self-reported subjective craving for cigarettes and for alcohol was recorded during each experimental session. Craving for cigarettes and alcohol increased significantly throughout the intravenous alcohol administration. A significant breath alcohol concentration (BrAC) × Medication interaction revealed that naltrexone blunted cigarette craving during alcohol administration, compared to placebo. Naltrexone significantly reduced craving for alcohol during alcohol administration in this group of heavy drinking smokers. Alcohol craving significantly predicted cigarette craving, however this effect did not vary across rising alcohol administration or by medication. These findings demonstrate that naltrexone reduces the urge to smoke and to drink during alcohol administration. Clinical studies are needed to further ascertain whether naltrexone may be of benefit to this distinct subgroup of heavy drinking smokers. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Distress Tolerance and Craving for Cigarettes Among Heavy Drinking Smokers

OBJECTIVE

Heavy drinking smokers experience significant difficulties with smoking cessation. Craving is closely tied to relapses during cessation attempts, and alcohol consumption increases cigarette craving among heavy drinking smokers. To date, however, few moderators of the relationship between craving and relapse have been identified. Individuals' capacity for distress tolerance predicts smoking cessation outcomes and may be connected to craving. Relatedly, pharmacotherapies like varenicline and naltrexone reduce cigarette and alcohol cravings, respectively. No studies have examined the interrelationships among distress tolerance, craving, and pharmacotherapy effects. This study therefore examines distress tolerance as a moderator of the relationship between overnight abstinence-induced cigarette craving and subsequent alcohol- and cigarette-induced changes in craving among heavy drinking smokers. This study also examines the impact of varenicline and naltrexone on these relationships.

METHOD

A total of 120 non-treatment-seeking heavy drinking smokers were randomized and titrated to one of the following conditions: (a) placebo, (b) varenicline, (c) naltrexone, or (d) varenicline + naltrexone. Participants then completed a laboratory paradigm after overnight abstinence that included consumption of alcohol (target .06 g/dl breath alcohol concentration) and one cigarette. Craving was assessed as abstinence-induced (Time 1), alcohol-induced (Time 2), and cigarette-induced (Time 3).

RESULTS

Within varenicline + naltrexone, low distress tolerance individuals exhibited higher increases from abstinence- to alcohol-induced cigarette craving relative to high distress tolerance individuals. Across medications, low distress tolerance individuals reported flatter decreases from abstinence- to cigarette-induced cigarette craving relative to high distress tolerance individuals.

CONCLUSIONS

Distress tolerance may differentially predict alcohol-induced cigarette craving when titrated to pharmacotherapy, as well as moderate decreases in craving after cigarette consumption. Future exploration of the identified interactive effects could elucidate specific conditions in which cravings are more proximally related to abstinence-induced smoking.

Distress Tolerance and Craving for Cigarettes Among Heavy Drinking Smokers

OBJECTIVE

Heavy drinking smokers experience significant difficulties with smoking cessation. Craving is closely tied to relapses during cessation attempts, and alcohol consumption increases cigarette craving among heavy drinking smokers. To date, however, few moderators of the relationship between craving and relapse have been identified. Individuals' capacity for distress tolerance predicts smoking cessation outcomes and may be connected to craving. Relatedly, pharmacotherapies like varenicline and naltrexone reduce cigarette and alcohol cravings, respectively. No studies have examined the interrelationships among distress tolerance, craving, and pharmacotherapy effects. This study therefore examines distress tolerance as a moderator of the relationship between overnight abstinence-induced cigarette craving and subsequent alcohol- and cigarette-induced changes in craving among heavy drinking smokers. This study also examines the impact of varenicline and naltrexone on these relationships.

METHOD

A total of 120 non-treatment-seeking heavy drinking smokers were randomized and titrated to one of the following conditions: (a) placebo, (b) varenicline, (c) naltrexone, or (d) varenicline + naltrexone. Participants then completed a laboratory paradigm after overnight abstinence that included consumption of alcohol (target .06 g/dl breath alcohol concentration) and one cigarette. Craving was assessed as abstinence-induced (Time 1), alcohol-induced (Time 2), and cigarette-induced (Time 3).

RESULTS

Within varenicline + naltrexone, low distress tolerance individuals exhibited higher increases from abstinence- to alcohol-induced cigarette craving relative to high distress tolerance individuals. Across medications, low distress tolerance individuals reported flatter decreases from abstinence- to cigarette-induced cigarette craving relative to high distress tolerance individuals.

CONCLUSIONS

Distress tolerance may differentially predict alcohol-induced cigarette craving when titrated to pharmacotherapy, as well as moderate decreases in craving after cigarette consumption. Future exploration of the identified interactive effects could elucidate specific conditions in which cravings are more proximally related to abstinence-induced smoking.