Alcohol-induced increases in smoking behavior for nicotinized and denicotinized cigarettes in men and women

Enhancing translation: A need to leverage complex preclinical models of addictive drugs to accelerate substance use treatment options

Preclinical models of addictive drugs have been developed for decades to model aspects of the clinical experience in substance use disorders (SUDs). These include passive exposure as well as volitional intake models across addictive drugs and have been utilized to also measure withdrawal symptomatology and potential neurobehavioral mechanisms underlying relapse to drug seeking or taking. There are a number of Food and Drug Administration (FDA)-approved medications for SUDs, however, many demonstrate low clinical efficacy as well as potential sex differences, and we also note gaps in the continuum of care for certain aspects of clinical experiences in individuals who use drugs. In this review, we provide a comprehensive update on both frequently utilized and novel behavioral models of addiction with a focus on translational value to the clinical experience and highlight the need for preclinical research to follow epidemiological trends in drug use patterns to stay abreast of clinical treatment needs. We then note areas in which models could be improved to enhance the medications development pipeline through efforts to enhance translation of preclinical models. Next, we describe neuroscience efforts that can be leveraged to identify novel biological mechanisms to enhance medications development efforts for SUDs, focusing specifically on advances in brain transcriptomics approaches that can provide comprehensive screening and identification of novel targets. Together, the confluence of this review demonstrates the need for careful selection of behavioral models and methodological parameters that better approximate the clinical experience combined with cutting edge neuroscience techniques to advance the medications development pipeline for SUDs.

Synthetic contraceptive hormones occlude the ability of nicotine to reduce ethanol consumption in ovary-intact female rats

Rates of tobacco and alcohol use in women are rising, and women are more vulnerable than men to escalating tobacco and alcohol use. Many women use hormonal birth control, with the oral contraceptive pill being the most prevalent. Oral contraceptives contain both a progestin (synthetic progesterone) and a synthetic estrogen (ethinyl estradiol; EE) and are contraindicated for women over 35 years who smoke. Despite this, no studies have examined how synthetic contraceptive hormones impact this pattern of polysubstance use in females. To address this critical gap in the field, we treated ovary-intact female rats with either sesame oil (vehicle), the progestin levonorgestrel (LEVO; contained in formulations such as Alesse®), or the combination of EE+LEVO in addition to either undergoing single (nicotine or saline) or polydrug (nicotine and ethanol; EtOH) self-administration (SA) in a sequential use model. Rats preferred EtOH over water following extended EtOH drinking experience as well as after nicotine or saline SA experience, and rats undergoing only nicotine SA (water controls) consumed more nicotine as compared to rats co-using EtOH and nicotine. Importantly, this effect was occluded in groups treated with contraceptive hormones. In the sequential use group, both LEVO alone and the EE+LEVO combination occluded the ability of nicotine to decrease EtOH consumption. Interestingly, demand experiments suggest an economic substitute effect between nicotine and EtOH. Together, we show that chronic synthetic hormone exposure impacts nicotine and EtOH sequential use, demonstrating the crucial need to understand how chronic use of different contraceptive formulations alter patterns of polydrug use in women.

The effect of alcohol use on smoking cessation: A systematic review

Only a small minority of all attempts to stop smoking are successful, especially among smokers who are heavy drinkers and those with an alcohol use disorder. The current systematic review focuses on the negative effects of alcohol use, either before or during attempts to quit smoking, on the success rate of these attempt(s) in alcohol-drinking tobacco smokers. We conducted a systematic review of naturalistic and experimental studies, which included at least 40 tobacco smokers with a recorded drinking status (non-drinking, heavy drinking, alcohol use disorder) and a clearly documented change in alcohol consumption. We could not conduct a meta-analysis and, thus, used consistency across studies to draw conclusions. The evidence presented here shows that alcohol use is associated with lower rates of success in quitting smoking in 20 out of 27 studies. This includes both lapses and relapses. Similarly, in 19 out of 20 long-term follow-up studies, the duration of smoking abstinence was shorter among persons with higher alcohol consumption. Finally, 12 out of 13 experimental studies showed that exposure of smokers to alcohol cues or to drinking of alcohol induce a strong propensity to smoke. It is, therefore, recommended for smokers who drink alcohol and who intend to quit smoking to use an integrated approach, i.e., to stop or substantially reduce their alcohol consumption before and/or during their attempt to quit smoking.

Addiction-Related Outcomes of Nicotine and Alcohol Co-use: New Insights Following the Rise in Vaping

PURPOSE

Nicotine and alcohol-containing products are some of the most commonly used substances of abuse and are both leading causes of preventable death. These substances also have significant interactions that have additive and, in some cases, multiplicative effects on the health consequences of their use. Thus, to reduce these negative consequences, it is important to understand the abuse liability of nicotine and alcohol in combination, especially in the most relevant use cases among those who are most vulnerable. Specifically, as tobacco cigarette use is continually decreasing, vaping is quickly replacing cigarettes as the primary mode of nicotine use. This pattern is especially true in adolescent populations in which vaping has grown considerably. Particularly concerning is that adolescents are more vulnerable than adults to the negative consequences of substance use. It is therefore imperative to revisit the literature as it relates to the rising state of co-use of vaping products with alcohol. Here, we review the clinical outcomes of nicotine and alcohol co-use as they relate to the abuse liability of each individually. Special attention is paid to adolescent findings, where available, as well as investigations that use nontobacco nicotine products as these may more accurately reflect the more recent trends of co-use.

IMPLICATIONS

Though nicotine alone has previously been considered a proxy for tobacco and tobacco cigarette use, combustible routes of administration have been decreasing. They are, instead, being replaced by e-cigarettes that do not involve other tobacco constituents and contain additional nonnicotine constituents of their own. Unfortunately, the literature remains limited with regard to e-cigarettes and their interactions with other substances, especially their prevalent co-use with alcohol. This review attempts to discuss the current literature on nicotine and alcohol co-use in the context of the vaping epidemic, predominantly focusing on addiction-related outcomes and why e-cigarette use may be unique.

The Effect of Alcohol Cue Exposure on Tobacco-Related Cue Reactivity: A Systematic Review

AIMS

To examine the effect of alcohol cue exposure on tobacco-related cravings, self-administration and other measures of tobacco-related cue reactivity.

METHODS

We searched Medline, PsycINFO, Embase, CINAHL and Scopus from inception to May 2020 for articles reporting on a combination of cue reactivity (and/or cross-cue reactivity), alcohol use and tobacco consumption. A semi-quantitative analysis and study quality assessment were performed for the included articles.

RESULTS

A total of 37 articles met our inclusion criteria and were included in the systematic review. Most studies (60%) reported that alcohol cue exposure increased tobacco cravings, but only 18% of studies reported that alcohol cue exposure resulted in an increase in ad libitum smoking. There was also substantial heterogeneity between studies due to differences in methodology related to alcohol cue exposure, measures of tobacco cravings, as well as variable participant and study characteristics.

CONCLUSIONS

Alcohol cue exposure can increase cravings for tobacco. This has important implications for individuals who use both substances but are trying to quit one or both.

Targeting the Opioid Receptors: A Promising Therapeutic Avenue for Treatment in “Heavy Drinking Smokers”

Aims

Despite a general decline in tobacco use in the last decades, the prevalence of tobacco smoking in individuals with alcohol use disorder (AUD) remains substantial (45–50%). Importantly, the co-use of both substances potentiates the adverse effects, making it a significant public health problem. Substantial evidence suggests that AUD and Tobacco use disorder (TUD) may share common mechanisms. Targeting these mechanisms may therefore provide more effective therapy. Numerous studies describe a potential role of the endogenous opioid system in both AUD and TUD. Reviewing this literature, we aim to evaluate the efficacy of molecules that target the opioid system as promising therapeutic interventions for treating alcohol and tobacco co-use disorders.

Methods

We provide a synthesis of the current epidemiological knowledge of alcohol and tobacco co-use disorders. We evaluate clinical and preclinical research that focuses on the regulation of the endogenous opioid system in alcohol, nicotine, and their interactions.

Results

The epidemiological data confirm that smoking stimulates heavy drinking and facilitates alcohol craving. Pharmacological findings suggest that treatments that are efficacious in the dual addiction provide a beneficial treatment outcome in comorbid AUD and TUD. In this regard, MOP, DOP and NOP-receptor antagonists show promising results, while the findings prompt caution when considering KOP-receptor antagonists as a treatment option in alcohol and tobacco co-use disorders.

Conclusions

Existing literature suggests a role of the opioid system in sustaining the high comorbidity rates of AUD and TUD. Molecules targeting opioid receptors may therefore represent promising therapeutic interventions in ‘heavy drinking smokers.’

Association of Alcohol Consumption and Ideal Cardiovascular Health Among South Asians: The Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study

BACKGROUND

Observational studies have shown that alcohol consumption above the recommended limit is associated with increased cardiovascular disease (CVD), although its association in South Asians is unclear. Less is known regarding the association between alcohol consumption and cardiovascular health (CVH), assessed by the American Heart Association's Life's Simple 7 (LS7) health metrics among those with South Asian ancestry.

METHODS

This analysis included 701 participants without CVD from the Mediators of Atherosclerosis in South Asians Living in America (MASALA) cohort (2015 to 2018). Based on a personal history questionnaire, participants were divided into never, former, and current drinkers. The current drinking category was further classified into 1 to 3 drinks/wk, 4 to 7 drinks/wk, and >7 drinks/wk. The consumption of 5 or more drinks on 1 occasion in the past month was defined as binge drinking. Each LS7 component was given a point score of 0, 1, or 2. The total score was categorized into 0 to 6, 7 to 10, and 11 to 14 to represent poor, intermediate, and ideal CVH, respectively. We use multinomial logistic regression to examine the association between alcohol consumption and CVH.

RESULTS

In the MASALA cohort (mean age = 59 years, 43% female), participants consuming >7 drinks/wk had the lowest mean CVH score. Compared with never drinkers, male participants consuming >7 drinks/wk were less likely to have intermediate CVH (0.44 [0.08, 0.91]) and ideal CVH (0.23 [0.03, 0.96]). Binge drinking was associated with significantly lower odds of ideal CVH compared with never drinkers.

CONCLUSION

We found evidence of an inverse association of moderate to heavy alcohol consumption and ideal CVH in South Asian men. These findings further underscore the important relationship between alcohol consumption and CVH in this unique population of South Asians.

Unequal interactions between alcohol and nicotine co-consumption: suppression and enhancement of concurrent drug intake

RATIONALE

Alcohol and nicotine addiction are prevalent conditions that co-occur. Despite the prevalence of co-use, factors that influence the suppression and enhancement of concurrent alcohol and nicotine intake are largely unknown.

OBJECTIVES

Our goals were to assess how nicotine abstinence and availability influenced concurrent alcohol consumption and to determine the impact of quinine adulteration of alcohol on aversion-resistant alcohol consumption and concurrent nicotine consumption.

METHODS

Male and female C57BL/6J mice voluntarily consumed unsweetened alcohol, nicotine, and water in a chronic 3-bottle choice procedure. In experiment 1, nicotine access was removed for 1 week and re-introduced the following week, while the alcohol and water bottles remained available at all times. In experiment 2, quinine (100-1000 μM) was added to the 20% alcohol bottle, while the nicotine and water bottles remained unaltered.

RESULTS

In experiment 1, we found that alcohol consumption and preference were unaffected by the presence or absence of nicotine access in both male and female mice. In experiment 2a, we found that quinine temporarily suppressed alcohol intake and enhanced concurrent nicotine, but not water, preference in both male and female mice. In experiment 2b, chronic quinine suppression of alcohol intake increased nicotine consumption and preference in female mice without affecting water preference, whereas it increased water and nicotine preference in male mice.

CONCLUSIONS

Quinine suppression of alcohol consumption enhanced the preference for concurrent nicotine preference in male and female mice, suggesting that mice compensate for the quinine adulteration of alcohol by increasing their nicotine preference.

The Interaction of Depressive Symptoms and Hazardous Drinking in Relation to Tobacco Craving Among Treatment Seeking Depressed Smokers: Sex Differences

OBJECTIVES

The present study sought to address whether there is sex effect in the interactive effect between depressive symptoms and hazardous drinking in the prediction of smoking craving after cognitive-behavioral smoking cessation treatment among those with at least mild depression.

METHODS

Participants (n = 114, mean age 42.0, SD = 9.73, 64% women) were treatment-seeking smokers who attended 6 weekly 1-hour sessions involving psychological treatment for cessation. Participants reported depressive symptoms and alcohol use at baseline and reported craving at baseline and after treatment.

RESULTS

Results indicated that there was a statistically significant 3-way interaction (depression by alcohol use by sex) for smoking craving (B = -0.30, standard error [SE] = 0.14, P = 0.042) and appetitive craving (B = -.21, SE = 0.09, P = 0.031), but not negative reinforcement craving. The form of the significant interactions indicted that higher levels of depressive symptoms and alcohol use were related to greater levels of craving at the end of treatment only among men.

CONCLUSIONS

The current findings provide novel empirical evidence suggesting that there is a clinically relevant interplay between depressive symptoms and alcohol use regarding general craving and appetitive craving among male treatment-seeking smokers. Although the present results should be replicated in larger samples, this type of research can inform the development of sex-specific interventions for smoking cessation.

A Critical Review of the Effects of Nicotine and Alcohol Coadministration in Human Laboratory Studies

Simultaneous use of cigarettes and alcohol is common and may be driven by nicotine increasing alcohol self-administration or vice versa. To better evaluate the causal nature of this relationship, we systematically reviewed human experimental laboratory studies that coadministered nicotine and alcohol with control conditions. Searches of PubMed/MEDLINE and PsycINFO databases and study bibliographies identified 30 studies that met our inclusion criteria. Research methodologies were critically reviewed. Effects of coadministration on drug self-administration and related factors such as craving, subjective response, motivation, and heart rate are reported. Results most strongly supported that alcohol increases nicotine and cigarette self-administration, whereas, depending on the context, nicotine increased, decreased, or had no effect on alcohol self-administration. Craving and subjective drug effects were also impacted by coadministration. Interaction effects of nicotine and alcohol on self-administration and subjective responses were reported infrequently. The effects may be moderated by a number of factors, including dose of administered drug and sex. Recommendations are made for future research, and clinical and policy implications of findings are discussed.

Nicotine Increases Alcohol Intake in Adolescent Male Rats

Background: Use of alcohol and tobacco, the two most concurrently abused drugs, typically first occurs during adolescence. Yet, there have been no systematic analyses of ethanol (EtOH) and nicotine (Nic) interactions during adolescence. Recent animal studies report that kappa-opioid (KOR) receptor activation mediates age differences in drug reinforcement. Our hypothesis is that concurrent self-administration of EtOH and Nic will be greater in adolescent rats because of age differences in KOR function. Furthermore, exposure to alcohol and nicotine during adolescence has been reported to increase EtOH intake in adulthood. We performed a longitudinal animal study and hypothesized adolescent rats allowed to self-administer nicotine would drink more alcohol as adults. Methods: Adolescent, postnatal day (P)32, and adult (P90) male and female Sprague-Dawley rats were allowed to self-administer EtOH, Nic, or a combination of both, EtOH+Nic, in an intravenous self-administration paradigm. The role of KOR was pharmacologically evaluated with the KOR antagonist, norbinaltorphamine (norBNI) and with the KOR agonist, U50,488H. Alcohol drinking was subsequently evaluated with male rats in a drinking in the dark (DID), 2-bottle choice test. Results: Concurrent Nic increased EtOH intake in adolescent males, but not in adults or females. Pharmacological blockade of KOR with norBNI robustly increased EtOH+Nic self-administration in adult male rats, but had no effect with female rats. Lastly, in our longitudinal study with male rats, we found prior self-administration of Nic or EtOH+Nic during adolescence increased subsequent oral EtOH intake, whereas prior self-administration of EtOH alone in adults increased subsequent EtOH drinking. Conclusions: There are major age- and sex-differences in the reinforcing effects of EtOH+Nic. Adolescent males are sensitive to the reinforcing interactions of the two drugs, whereas this effect is inhibited by KOR activation in male adults. Nicotine self-administration in adolescent males also increased subsequent oral EtOH intake. These findings suggest that brain mechanisms underlying the reinforcing effects of EtOH and nicotine are both age- and sex-dependent, and that tobacco or e-cigarette use may increase the vulnerability of teenage boys to alcohol abuse.

Alcohol consumption as a predictor of reactivity to smoking and stress cues presented in the natural environment of smokers

BACKGROUND AND RATIONALE

The high prevalence of co-occurring alcohol and tobacco use underscores the importance of understanding the influence of alcohol consumption on risk factors for smoking and relapse. Alcohol has been shown to impact reactivity to smoking and stress-related cues, both of which are common antecedents to smoking and smoking relapse.

OBJECTIVE

The objective of the current study is to examine associations between alcohol use, cigarette craving, and stress reactivity following exposure to smoking and stress cues delivered in participants' daily lives.

METHODS

Using cue-reactivity ecological momentary assessment (CREMA), adult smokers (n = 138) reported cigarette craving, stress, and past hour alcohol use on a mobile device four times per day for 2 weeks, resulting in a range of 4493-5983 data points per analysis. Questions were followed by exposure to pictorial neutral, stressful, or smoking cues delivered via the mobile device. Craving and affect were re-assessed following cue exposure.

RESULTS

Results showed that recent (past hour) alcohol use was significantly associated with increases in the following: (a) tonic (non-cue-elicited) cigarette craving, (b) stress cue-elicited cigarette craving, and (c) stress cue-elicited stress reactivity, in the context of high-baseline stress. There was no significant association between alcohol use and smoking cue-elicited craving.

CONCLUSIONS

Alcohol use may increase risk for smoking and relapse to smoking by increasing cigarette craving and, in certain contexts, stress following stress cue exposure. Though alcohol is known for its anxiolytic properties, under some conditions, it may increase reactivity to stress cues.

Inhalation of Alcohol Vapor: Measurement and Implications

Decades of alcohol research have established the health risks and pharmacodynamic profile of oral alcohol consumption. Despite isolated periods of public health concern, comparatively less research has evaluated exposure to alcohol vapor. Inhaled alcohol initially bypasses first-pass metabolism and rapidly reaches the arterial circulation and the brain, suggesting that this route of administration may be associated with pharmacological effects that increase the risk of addiction. However, detailed reviews assessing the possible effects of inhaled alcohol in humans are lacking. A comprehensive, systematic literature review was conducted using Google Scholar and PubMed to examine manuscripts studying exposure to inhaled alcohol and measurement of biomarkers (biochemical or functional) associated with alcohol consumption in human participants. Twenty-one publications reported on alcohol inhalation. Fourteen studies examined inhalation of alcohol vapor associated with occupational exposure (e.g., hand sanitizer) in a variety of settings (e.g., naturalistic, laboratory). Six publications measured inhalation of alcohol in a controlled laboratory chamber, and 1 evaluated direct inhalation of an e-cigarette with ethanol-containing "e-liquid." Some studies have reported that inhalation of alcohol vapor results in measurable biomarkers of acute alcohol exposure, most notably ethyl glucuronide. Despite the lack of significantly elevated blood alcohol concentrations, the behavioral consequences and subjective effects associated with repeated use of devices capable of delivering alcohol vapor are yet to be determined. No studies have focused on vulnerable populations, such as adolescents or individuals with alcohol use disorder, who may be most at risk of problems associated with alcohol inhalation.

Relationship between negative affect and smoking topography in heavy drinking smokers

Heavy drinking smokers represent a sizeable subgroup of smokers for whom nicotine deprivation and alcohol use increases the urge to smoke in the laboratory and predicts lapses during smoking cessation. The manner in which individuals smoke a cigarette (i.e. smoking topography) provides a reliable index of smoking intensity and reinforcement, yet the effects of affect on smoking topography have not been thoroughly examined in heavy drinking smokers. The current study examined how affect and nicotine deprivation predict smoking behavior as participants (N=27) smoked one cigarette using a smoking topography device after 12-h of nicotine abstinence and after a priming dose of alcohol (target BrAC=0.06g/dl). Primary smoking topography measures were puff volume, velocity, duration, and inter-puff interval (IPI). The effect of nicotine deprivation was measured by the Minnesota Nicotine Withdrawal Scale (MNWS) and the Profile of Mood States (POMS). Measures were obtained at baseline (i.e. 12-h of nicotine abstinence and pre-alcohol) and 30-minutes after alcohol administration (i.e. peak BrAC). Results revealed post-priming negative affect significantly moderated the trajectories of puff volume, puff duration and IPI (p's<0.05) over the course of the cigarette, such that those with greater negative affect had flatter slopes for volume and duration and increasingly infrequent puffs. Our results suggest that baseline and post-priming negative affect following nicotine deprivation alters smoking patterns and increases nicotine exposure throughout a single cigarette. Future studies need to examine differential amounts of nicotine deprivation on response to alcohol and smoking in heavy drinking smokers.

Hazardous Alcohol Drinking as Predictor of Smoking Relapse (3-, 6-, and 12-Months Follow-Up) by Gender

Diverse studies have found a relation between alcohol consumption and smoking relapse. Few studies have analyzed the relation of smoking relapse with pretreatment alcohol consumption and gender differences. The main purpose of this study is to analyze the influence of alcohol consumption in smoking relapse over 12 months (3-, 6-, and 12-months follow-up) and to determine possible gender differences. The sample included 374 smokers who quit smoking by participating in a psychological smoking cessation treatment. We assessed hazardous pretreatment alcohol drinking (AUDIT), cigarette consumption (FTND; number of cigarettes) and sociodemographic variables. Higher scores on hazardous pretreatment alcohol drinking predict smoking relapse at 3-, 6-, and 12-months after smoking cessation. In males, higher scores on hazardous pretreatment alcohol drinking predict relapse at 6 and at 12 months. In females, higher scores on hazardous pretreatment alcohol drinking predict tobacco relapse at 3 months. Hazardous pretreatment alcohol drinking predicts relapse at all intervals after smoking cessation (3-, 6-, and 12-months follow-up). However, the influence of hazardous pretreatment alcohol drinking on smoking relapse differs as a function of gender, as it is a short-term predictor in women (3 months) and a long-term predictor in men (6 and 12 months).

An overview of alcohol and tobacco/nicotine interactions in the human laboratory

BACKGROUND

Alcohol use disorders and tobacco use contribute significant risk to the global burden of disease, and each are major public health concerns. Together, alcohol and tobacco use are highly comorbid and have multiplicative health risks when used concurrently, underscoring the importance of examining alcohol-tobacco interactions in the human laboratory.

OBJECTIVE

The aims of this review were to summarize the state of research examining alcohol-tobacco interactions in the human laboratory.

METHODS

We reviewed human laboratory evidence for alcohol and tobacco/nicotine interactions, including 1) craving in drinkers and smokers exposed to smoking or drinking cues, 2) fixed-dosing of alcohol or nicotine in smokers and drinkers, and 3) smoking and alcohol influences on self-administration behaviors. The interactive effects of tobacco/nicotine with other drugs of abuse are also briefly discussed.

RESULTS

Overall, results identified that alcohol and tobacco have reciprocal influences on potentiating craving, subjective responses to fixed-dose alcohol or nicotine administration, and self-administration. The literature identified that alcohol increases craving to smoke, decreases time to initiate smoking, and increases smoking self-administration. Similarly, tobacco and nicotine increase alcohol craving, decrease subjective effects of alcohol, and increase alcohol consumption.

CONCLUSION

Future studies should continue to focus on alcohol and tobacco/nicotine interactions in individuals with a wide scope of drinking and smoking histories, different states of alcohol and nicotine deprivation, and influences of either drug on craving, subjective responses, and consumption over the course of the blood alcohol curve. This work could have important implications for the impact of alcohol-tobacco interactions on guiding clinical practice, as well as in the changing landscape of addiction.

Voluntary co-consumption of alcohol and nicotine: Effects of abstinence, intermittency, and withdrawal in mice

Alcohol and nicotine are often used together, and there is a high rate of co-occurrence between alcohol and nicotine addiction. Most animal models studying alcohol and nicotine interactions have utilized passive drug administration, which may not be relevant to human co-addiction. In addition, the interactions between alcohol and nicotine in female animals have been understudied, as most studies have used male animals. To address these issues, we developed models of alcohol and nicotine co-consumption in male and female mice that utilized voluntary, oral consumption of unsweetened alcohol, nicotine and water. We first examined drug consumption and preference in single-drug, sequential alcohol and nicotine consumption tests in male and female C57BL/6 and DBA/2J mice. We then tested chronic continuous and intermittent access alcohol and nicotine co-consumption procedures. We found that male and female C57BL/6 mice readily co-consumed unsweetened alcohol and nicotine. In our continuous co-consumption procedures, we found that varying the available nicotine concentration during an alcohol abstinence period affected compensatory nicotine consumption during alcohol abstinence, and affected rebound alcohol consumption when alcohol was re-introduced. Consumption of alcohol and nicotine in an intermittent co-consumption procedure produced higher alcohol consumption levels, but not nicotine consumption levels, compared with the continuous co-consumption procedures. Finally, we found that intermittent alcohol and nicotine co-consumption resulted in physical dependence. Our data show that these voluntary co-consumption procedures can be easily performed in mice and can be used to study behavioral interactions between alcohol and nicotine consumption, which may better model human alcohol and nicotine co-addiction.

Health-Related Quality of Life With Regard to Smoking, Consumption of Alcohol, and Sports Participation

BACKGROUND

Health-related quality of life (HRQoL) is an important determinant in a person's life.

OBJECTIVES

In this study aimed at physical education students, alcohol consumption and smoking as risk factors and sports as a healthy factor could affect HRQoL.

PATIENTS AND METHODS

This study was an analytical cross-sectional study. For our purpose, the subjects (n = 519) were asked to answer the SF-36 questionnaire (short form health survey for HRQOL). To analyze the data, two-way multivariate analysis of variance (MANOVA), one-way analysis of variance (ANOVA), the independent-samples t-test, and Pearson correlation coefficient were conducted. In this study, the P < 0.05 was considered a significant difference, and due to a Bonferroni correction, for ANOVAs tests, a P < 0.0125 was considered a significant difference.

RESULTS

The results suggest that statistically significant differences for alcohol consumption were only obtained from the role-emotional (RE) scale, in which drinkers had lower mean scores than nondrinkers. For smoking, significant differences were obtained from the scales of RE, vitality (VT), emotional well-being (EW), social functioning (SF), and general health (GH), in which nonsmokers outdid smokers. The combination of alcohol drinking and smoking led to statistically significant lower scores on the RE scale and strongly destroyed the role-emotional part of HRQOL.

CONCLUSIONS

It can be concluded that smoking and alcohol consumption may be related to poor HRQOL in physical education and sports students despite the fact that they regularly engage in sports programs that could positively affect their HRQOL.

The Reliability and Stability of Puff Topography Variables in Non-Daily Smokers Assessed in the Laboratory

INTRODUCTION

Puff topography variables, often measured using the Clinical Research Support System device, have traditionally been studied in regular, daily smokers and have been shown to be highly stable. However, more recent research has focused on non-daily smokers as a population of interest. As such, the aim of this article was to examine puff topography stability (cross-cigarette agreement over time) and reliability (within-cigarette consistency) in non-daily smokers across six laboratory sessions.

METHODS

One hundred seven non-daily smokers attended six laboratory sessions over the course of 3 months. At each session, they smoked one cigarette through the Clinical Research Support System pocket, in addition to completing questionnaires about their smoking history and dependence.

RESULTS

Puff topography measurements were highly reliable (α values ranged from 0.87-0.95) and puff behavior was highly stable across sessions (r values ranged from 0.38-0.84). Adding sessions substantially improved reliability estimates. Aspects of puffing behavior observed in session, including puff volume, puff duration, time of puff peak, and total cigarette volume were related to level of smoke exposure, measured by expired carbon monoxide. Instability in puffing behavior was not predicted by recent or long-term smoking patterns.

CONCLUSIONS

Puff topography appears to be a stable and routinized aspect of smoking in non-daily smokers. The feasibility of assessing puff topography in this population is supported by the high reliabilities observed, though it should be noted that reliability greatly improved by having more than one session.

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.

Smoking Through a Topography Device Diminishes Some of the Acute Rewarding Effects of Smoking

BACKGROUND

Smoking topography (ST) devices are an important methodological tool for quantifying puffing behavior (eg, puff volume, puff velocity) as well as identifying puffing differences across individuals and situations. Available ST devices are designed such that the smoker's mouth and hands have direct contact with the device rather than the cigarette itself. Given the importance of the sensorimotor aspects of cigarette smoking in smoking reward, it is possible that ST devices may interfere with the acute rewarding effects of smoking. Despite the methodological importance of this issue, few studies have directly compared subjective reactions to smoking through a topography device to naturalistic smoking.

METHODS

Smokers (N = 58; 38% female) smoked their preferred brand of cigarettes one time through a portable topography device and one time naturalistically, in counterbalanced order across two laboratory sessions. Smoking behavior (eg, number of puffs) and subjective effects (eg, urge reduction, affect, smoking satisfaction) were assessed.

RESULTS

Negative affect reduction was greater in the natural smoking condition relative to the topography condition, but differences were not significant on measures of urge, withdrawal, or positive affect. Self-reported smoking satisfaction, enjoyment of respiratory tract sensations, psychological reward, craving reduction, and other rewarding effects of smoking were also significantly greater in the naturalistic smoking condition.

CONCLUSIONS

The effects of using a ST device on the smoking experience should be considered when it is used in research as it may diminish some of the rewarding effects of smoking.

IMPLICATIONS

When considering the inclusion of a smoking topography device in one's research, it is important to know if use of that device will alter the smoker's experience. This study assessed affective and subjective reactions to smoking through a topography device compared to naturalistic smoking. We found that smoking satisfaction, psychological reward, enjoyment of respiratory tract sensations and other rewarding effects were all diminished when smoking through the topography device. The effects of using a smoking topography device on the smoking experience should be considered when it is used in future research.

Heavy-Drinking Smokers' Treatment Needs and Preferences: A Mixed-Methods Study

The purpose of this mixed methods study was to describe the smoking and psychological characteristics of heavy-drinking smokers, their perceptions of smoking and drinking, and their smoking and alcohol treatment preferences to inform an integrated smoking and alcohol intervention. Heavy-drinking smokers (N=26) completed standardized surveys and participated in semi-structured focus group interviews. Participants reported a strong association between their smoking and drinking. Participants were more motivated to quit smoking than to reduce their drinking but perceived greater barriers to smoking cessation. Stress/negative affect was closely linked with both behaviors. They expressed overall enthusiasm for a smoking and alcohol intervention but had specific format and content preferences. Half preferred an integrated treatment format whereas others preferred a sequential treatment model. The most preferred content included personalized health feedback and a way to monitor health gains after behavior changes.

Positive smoking outcome expectancies mediate the relation between alcohol consumption and smoking urge among women during a quit attempt

Social learning models of addiction hypothesize that situational factors interact with cognitive determinants to influence a person's motivation to use substances. Ecological momentary assessment was used to examine the association between alcohol consumption, smoking outcome expectancies, and smoking urge during the first 7 days of a smoking quit attempt. Participants were 113 female smokers who enrolled in a study that tested an individually tailored smoking cessation treatment. Participants carried a palm-top personal computer for 7 days and were instructed to complete 4 random assessments each day and to initiate an assessment when they were tempted to smoke. Multilevel mediational analyses were used to examine (a) the effects of alcohol consumption before time j and positive smoking outcome expectancies at time j on smoking urge at time j + 1 (Model 1) and (b) the effects of alcohol consumption before time j and smoking urge at time j on positive smoking outcome expectancies at time j + 1 (Model 2). Model 1 found a significant effect of alcohol consumption before time j on smoking urge at time j + 1 (p = .04), and this effect was significantly mediated by positive smoking outcome expectancies at time j (p < .0001). Model 2 failed to find a significant effect of alcohol consumption before time j on positive smoking outcome expectancies at time j + 1. The findings suggest that alcohol consumption is significantly associated with increased positive smoking outcome expectancies that, in turn, are associated with increased smoking urge in women seeking to quit smoking.

Brain regions affected by impaired control modulate responses to alcohol and smoking cues

OBJECTIVE

Despite the commonly observed comorbidity of alcohol and tobacco use disorders and years of research, the mechanism underlying concurrent use of alcohol and tobacco is not yet clear. In this study, we used functional magnetic resonance imaging (fMRI) to investigate the relationship between brain responses to alcohol and smoking cues in 45 subjects with episodic drinking and regular smoking.

METHOD

fMRI data were collected from two studies performing an alcohol-craving task and a smoking-craving task. First, we identified brain voxels significantly activated for both substance cues and then associated the activation of these voxels with various alcohol- and nicotine-dependence measures. Significant clusters (cluster-wise p < .05) correlated with behavioral assessments were extracted, and clusters identified from both cues were compared.

RESULTS

The association tests with various dependence scores showed that the loss of behavioral control subcategory in the Alcohol Dependence Scale was significantly correlated with brain activation of the posterior cingulate cortex (PCC) and right posterior insula regardless of cue types.

CONCLUSIONS

Our findings suggest that the PCC and right posterior insula, each playing a role in the salience network, are affected significantly by impaired control for alcohol and in turn influence brain responses to not only alcohol but also smoking cues, providing insight to neuronal mechanisms for concurrent use or comorbidity of alcohol and nicotine dependence.

Combined varenicline and naltrexone treatment reduces smoking topography intensity in heavy-drinking smokers

Heavy drinking smokers constitute a distinct sub-population of smokers for whom traditional smoking cessation therapies may not be effective. Recent evidence suggested that combined varenicline (VAR) and naltrexone (NTX) therapy may be more efficacious than either monotherapy alone in reducing smoking and drinking-related behavior in this population. The manner in which individuals smoke a cigarette (i.e., smoking topography) may be predictive of smoking cessation outcomes, yet the effects of smoking pharmacotherapies on puffing behavior have not been thoroughly examined. Therefore, the current double-blind medication study examined the effects of VAR alone (1mg BID), low dose NTX alone (25mg QD), the combination of VAR+NTX, and placebo on smoking topography measures in heavy drinking, non-treatment seeking daily smokers (n=120). After a 9-day titration period, participants completed a laboratory session in which they smoked their first cigarette of the day using a smoking topography device following 12h of nicotine abstinence and consumption of an alcoholic beverage (BrAC=0.06g/dl). The primary measures were puff count, volume, duration, and velocity and inter-puff interval (IPI). Independent of medication group, puff velocity and IPI increased, while puff volume and duration decreased, over the course of the cigarette. The active medication groups, vs. the placebo group, had significantly blunted puff duration and velocity slopes over the course of the cigarette, and this effect was particularly evident in the VAR+NTX group. Additionally, the VAR+NTX group demonstrated lower average IPI than the monotherapy groups and lower average puff volume than all other groups. These results suggest that smoking pharmacotherapies, particularly the combination of VAR+NTX, alter smoking topography in heavy drinking smokers, producing a pattern of less intense puffing behavior. As smoking topography has been predictive of the ability to quit smoking, future studies should examine how smoking pharmacotherapies' effects on puffing behavior relate to smoking cessation outcomes.

Nicotine enhances the locomotor stimulating but not the conditioned rewarding effect of ethanol in DBA/2J mice

BACKGROUND

One hypothesis to explain the high rate of nicotine and alcohol (ethanol [EtOH]) co-abuse is that these drugs have enhanced rewarding effects when taken together. The goal of this work was to use the conditioned place preference (CPP) procedure to determine whether nicotine would enhance the development of EtOH-induced CPP.

METHODS

The conditioned rewarding effects of nicotine (1 or 2 mg/kg of nicotine tartrate), EtOH (1 g/kg), and nicotine plus EtOH in combination were assessed using a well-established CPP procedure chosen specifically for examining alterations in the development of EtOH-induced CPP by nicotine. In addition, the reference dose procedure was used to directly compare the conditioned rewarding effect of EtOH versus nicotine plus EtOH. DBA/2J mice were used because they are an inbred strain that has repeatedly been shown to develop CPP to EtOH.

RESULTS

Neither dose of nicotine alone produced CPP, whereas EtOH did, using the standard EtOH CPP procedure. The magnitude of EtOH-induced CPP was not affected by co-administration of 1 mg/kg nicotine, but 2 mg/kg nicotine interfered with the development of EtOH-induced CPP. Using the reference dose procedure, there was no significant preference or aversion for either nicotine + EtOH dose combination versus EtOH alone. However, combined nicotine and EtOH had a larger effect on locomotor activity, during the conditioning trials, compared to their additive effect when given alone, consistent with previous data.

CONCLUSIONS

These data do not support the hypothesis that nicotine enhances the conditioned rewarding effect of EtOH. This finding differs from the combined locomotor stimulant effects of nicotine and EtOH that were observed in this study and in our previously published work, and suggests that combined stimulant effects of nicotine and EtOH do not predict enhanced reward.

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.

Naltrexone improves quit rates, attenuates smoking urge, and reduces alcohol use in heavy drinking smokers attempting to quit smoking

BACKGROUND

Heavy drinking smokers (HDS) have more difficulty quitting smoking than lighter drinkers or abstainers. The opioid antagonist naltrexone may improve smoking quit rates and reduce alcohol use in drinker-smokers, but its relative efficacy in smokers with a range of drinking patterns is unknown. The current study tested the hypothesis that HDS would show differential benefit of naltrexone versus placebo relative to moderate-to-light or nondrinking smokers in terms of improving smoking outcomes and reducing alcohol consumption.

METHODS

Adult smokers (N = 315) enrolled in a 12-week, double-blinded, placebo-controlled trial of 50 mg naltrexone for smoking cessation were categorized into subgroups based upon past 6-month drinking patterns: HDS (n = 69; i.e., averaged ≥2 heavy drinking episodes per month), moderate-to-light drinking smokers (n = 204, i.e., consumed 1 drink up to a maximum of <2 heavy drinking episodes per month on average), or nondrinking smokers (n = 42, no alcohol consumed in the past 6 months). The groups were compared on the main study outcomes of biochemically verified prolonged abstinence quit rates (i.e., no smoking weeks 2 to 12), and smoking urge and alcohol use (drinks/wk) during treatment.

RESULTS

Naltrexone significantly increased 12-week smoking abstinence rates and decreased smoking urge and alcohol use among HDS, but not moderate-to-light or nondrinking smokers. Mediation analyses in HDS revealed that naltrexone's effect on smoking urge during the first 4 weeks of treatment mediated its effect on quit rates.

CONCLUSIONS

HDS appear to be particularly sensitive to naltrexone effects on smoking and drinking outcomes. This group may represent an important target for adjunctive treatment with naltrexone to optimize smoking cessation outcomes.

Nicotine interactions with low-dose alcohol: pharmacological influences on smoking and drinking motivation

An extensive literature documents a close association between cigarette and alcohol use. The joint pharmacological effects of alcohol and nicotine on smoking and drinking motivation may help explain this relationship. This experiment was designed to test the separate and combined pharmacological effects of nicotine and a low dose of alcohol (equivalent to 1-2 standard drinks) on substance use motivation using a double-blind and fully crossed within-subjects design. Participants (N = 87) with a wide range of smoking and drinking patterns completed 4 counterbalanced experimental sessions during which they consumed an alcohol (male: 0.3g/kg; female: 0.27g/kg) or placebo beverage and smoked a nicotine (.6 mg) or placebo cigarette. Outcome measures assessed the impact of drug administration (alcohol or nicotine) on craving to smoke, craving to drink, affect, and liking of the beverage and cigarette. Results indicated that combined administration produced higher cravings to smoke for the entire sample, as well as higher cravings to drink among women and lighter drinkers. Heavier users of either alcohol or cigarettes also exhibited enhanced sensitivity to the effects of either drug in isolation. Separate, but not interactive, effects of alcohol and nicotine on mood were observed as well as both same-drug and cross-drug effects on beverage and cigarette liking. Together, these findings support the notion that the interactive pharmacological effects of nicotine and low doses of alcohol play an important role in motivating contemporaneous use and suggest roles for cross-reinforcement and cross-tolerance in the development and maintenance of alcohol and nicotine use and dependence.

Comparison of the reinforcing properties of nicotine and cigarette smoke extract in rats

Tobacco dependence is difficult to treat, with the vast majority of those who try to quit relapsing within the first year. Improvements in smoking cessation therapies may be achieved by improving current preclinical research methods. However, most experimental tests in animals use nicotine alone, ignoring the 8000 other constituents found in tobacco smoke. To improve on this model, we have used self-administration to test the reinforcing properties of aqueous cigarette smoke extract (CSE) in rats, made by bubbling cigarette smoke through a saline solution. CSE is more potent than nicotine alone in both the acquisition and maintenance of self-administration, but did not exhibit higher progressive ratio responding. Mecamylamine and varenicline had similar potencies to block nicotine and CSE self-administration, indicating the involvement of nicotinic receptors in CSE reinforcement. Following extinction of responding, reinstatement was triggered by exposing animals to a pharmacological stressor, yohimbine (2.5 mg/kg, i.p.), alone and in combination with cues. Animals that self-administered CSE were significantly more sensitive to stress-induced reinstatement than those that self-administered nicotine. Ligand binding autoradiography studies showed nicotine and CSE to have similar affinities for different nicotinic receptor types. CSE significantly reduced MAO-A and MAO-B activities in vitro, whereas nicotine did not. Although CSE inhibition of MAO-A activity in vitro was found to be partially irreversible, irreversible inhibition was not observed in vivo. These experiments show that CSE is an effective reinforcer acting via nicotinic receptors. Furthermore, it better models MAO inhibition and is more sensitive to stress-induced reinstatement than nicotine alone, which is a potent trigger for relapse in smokers.

Length of smoking deprivation moderates the effects of alcohol administration on urge to smoke

Although smoking deprivation is often used in laboratory studies to induce urges to smoke cigarettes, the optimal length of deprivation has not been established. Previous research showed that overnight abstinence from cigarettes led to high baseline urge to smoke that potentially masked alcohol's acute effects on urge to smoke (Kahler et al., 2012). The current study examined whether alcohol's effects on smoking urge were more pronounced when a shorter length of smoking deprivation was used (i.e., 3h instead of overnight abstinence). Using a balanced placebo design for alcohol administration, we found that participants experienced a significant increase in self-reported urge to smoke when administered alcohol after a 3-h smoking deprivation (n=32), whereas this effect was smaller and nonsignificant when smokers were required to be abstinent overnight (n=96). Research on factors that heighten smoking urges may find stronger effects if a 3-h deprivation is used compared to using overnight abstinence.

The effect of snus on alcohol-related cigarette administration in dependent and non-dependent smokers

INTRODUCTION

Alcohol has been found to increase tobacco smoking in both dependent daily smokers (DDS) and nondependent nondaily smokers (NNS), yet little attention has been directed toward examining how different treatments/products modify drinking-related smoking behavior.

METHODS

This study examined the acute effects of snus (4mg of nicotine) on alcohol-related smoking responses in 18 DDS and 17 NNS. During each double-blind session, participants were randomly assigned to receive one of the following combinations: alcohol and snus, alcohol and placebo snus, placebo alcohol and snus, or placebo alcohol and placebo snus. Participants consumed their assigned beverage before absorbing their session's product, and after 30min participants could self-administer puffs of their preferred brand of cigarette over a 60-minute period using a progressive ratio task.

RESULTS

Alcohol significantly increased tobacco craving (p<.001) and tended to decrease latency to start smoking (p=.021) but only among NNS. In contrast, snus tended to decrease the number of puffs earned and how hard DDS worked for puffs in both beverage conditions (ps≤.019) but it did not alter the smoking behavior of NNS. Craving was not significantly impacted by snus in either type of smoker.

DISCUSSION

These findings raise the possibility that different processes mediate alcohol and cigarette co-use in NNS and DDS and suggest that snus may be effective in reducing alcohol-related cigarette use in DDS specifically.

A systematic review and analysis of data reduction techniques for the CReSS smoking topography device

Introduction: Characterising smoking behaviour in an objective and ecologically valid manner is integral to understanding health complications associated with tobacco use. Smoking topography (ST) provides a representation of the physical attributes of smoking. However, there is no clear guidance on ST data exclusion and reduction techniques and the impact of different techniques.

Methods: A search was conducted using MEDLINE, PubMed, and Scopus and limited to studies published between 2001‒2012. The search identified 23 studies using the CReSS device.

Results: Few studies reported data reduction (n = 9) and exclusion (n = 4) criteria. Four data reduction techniques emerged and were applied to an existing dataset (n = 193, Mage = 38.98, FTND = 5.19, mean 17.23 cigarettes/day). Using repeated measures ANOVA, there were significant (p < 0.05) differences among all techniques for puff volume, peak flow, puff duration and interpuff interval, which were attenuated upon controlling for puff count.

Conclusions: This review highlights the inconsistency in the literature regarding the disclosure of smoking topography data treatment and provides clear evidence that outcomes vary depending on the technique used. Greater transparency is needed and consideration should be given by researchers to the potential impact of methodological decisions on study findings.

Pilot randomized trial on mindfulness training for smokers in young adult binge drinkers

Background

We report results of a pilot study designed to test a novel smoking cessation intervention, Mindfulness Training for Smokers (MTS), in smokers age 18-29 years with regular episodes of binge drinking. Mindfulness is a cognitive skill of applying close moment-to-moment attention to experience with a mental posture of acceptance and non-reactivity. The MTS intervention consisted of six weekly classes that provided instruction on how to use mindfulness to manage known precursors of smoking relapse including smoking triggers, strong emotions, stressful situations, addictive thoughts, urges, and withdrawal symptoms.

Methods

The MTS intervention was compared to Interactive Learning for Smokers (ILS), a time/intensity matched control group using daily non-directed walking instead of mindfulness meditation. Recruitment was conducted primarily at local technical colleges. Primary outcome measures included biochemically-confirmed smoking abstinence and reduction in alcohol use at the end of treatment (2-weeks post-quit attempt).

Results

The sample (N = 55) was 70.9% male, with a mean age of 21.9 years, and a mean of 11.76 alcoholic drinks consumed per week. Intent-to-treat analysis showed biochemically-confirmed 7-day point prevalence abstinence rates at 2-weeks post-quit for MTS = 20.0% and ILS = 4.0%, p = .08. Secondary analysis showed number of drinks per week in the first 2-weeks post-quit correlated with smoking relapse at 2-weeks post-quit (p < .01).

Conclusions

This pilot study demonstrated that Mindfulness Training for Smokers shows promise for smoking cessation and alcohol use reduction in treating young adult smokers with alcohol abuse. Results suggest the need for a study with larger sample size and methods that reduce attrition.

Trial registration

ClnicalTrial.gov, NCT01679236

Alcohol attenuates amygdala-frontal connectivity during processing social signals in heavy social drinkers: a preliminary pharmaco-fMRI study

RATIONALE

Convergent evidence shows that alcohol exerts its effects on social behavior via modulation of amygdala reactivity to affective stimuli. Given that affective processing involves dynamic interactions between the amygdala and the prefrontal cortex (PFC), alcohol's effects are likely to extend beyond regional changes in brain activity to changes that manifest on a broader functional circuit level.

OBJECTIVE

The current study examines alcohol's effects on functional connectivity (i.e., "coupling") between the amygdala and the PFC during the processing of socio-emotional stimuli using functional magnetic resonance imaging (fMRI).

METHODS

In a randomized, double blind, placebo-controlled, within-subjects cross-over design, 12 heavy, social drinkers performed an fMRI task designed to probe amygdala response to socio-emotional stimuli (angry, fearful, and happy faces) following acute ingestion of alcohol or placebo. Functional connectivity between the amygdala and PFC was examined and compared between alcohol and placebo sessions using a conventional generalized psychophysiological interaction (gPPI) analysis.

RESULTS

Relative to placebo, alcohol reduced functional coupling between the amygdala and the right orbitofrontal cortex (OFC) during processing of both angry and fearful faces. Alcohol also reduced functional coupling between the amygdala and left OFC during processing of happy faces.

CONCLUSIONS

These preliminary findings suggest that alcohol's effects on social behavior may be mediated by alternations in functional connectivity between the amygdala and OFC during processing of emotional faces.

Coronary artery disease and its risk factors in patients presenting for liver transplantation

STUDY OBJECTIVE

To determine the distribution of coronary artery disease (CAD) and its risk factors across the various etiologies of end-stage liver disease, and to elucidate the relationship between severe alcohol consumption and CAD.

DESIGN

Retrospective multicenter study analysis.

SETTING

National Standard Transplant Analysis and Research file data.

MEASUREMENTS

Data from all primary adult orthotopic liver transplant recipients during the period from 2004 through 2006 were studied. Data were divided into 5 groups according to each patient's etiology of end-stage liver disease. The prevalence of CAD and the distribution of its risk factors were compared among groups.

MAIN RESULTS

17,482 cases were studied. The incidence of CAD was highest in nonalcoholic hepatic steatosis (7.4%) and lowest in biliary cirrhosis (1.7%). No difference in prevalence of CAD and its risk factors was noted between the viral and alcoholic etiologies (Hepatitis C 2.7%, Hepatitis B 2.3%, and alcoholic cirrhosis 2.9%).

CONCLUSIONS

Prevalence of CAD and the distribution of CAD risk factors in patients with severe alcohol consumption were similar to patients with viral hepatitis. CAD was most prevalent in patients with hepatic steatosis. This study argues against the notion of decreased expression and progression of CAD in patients with alcoholic cirrhosis presenting for liver transplantation.

Participation of central imidazoline binding sites in antinociceptive effect of ethanol and nicotine in rats

Despite synergistic morbidity and mortality, concomitant consumption of alcohol and tobacco is increasing, and their antinociceptive effect has been linked with co-abuse. Present study was designed to investigate the role of imidazoline binding sites in the antinociceptive effect of nicotine, ethanol, and their combination. Separate group of male Sprague-Dawley rats (200-250 g) were treated with different doses of alcohol (0.50-2 g/kg, i.p.) or nicotine (0.25-1 mg/kg, i.p.), and their combination evaluated in tail flick test. Influence of endogenous imidazoline binding site ligands, agonist, and antagonists were determined by their prior treatment with effective or subeffective doses of either ethanol or nicotine. Ethanol, nicotine, or their subeffective dose combination exhibited significant antinociceptive effects in dose-dependent manner. Antinociceptive effect of ethanol and nicotine was significantly augmented by intracerebroventricular (i.c.v.) administration of endogenous imidazoline receptor ligands, harmane (25 μg/rat, i.c.v.) and agmatine (10 μg/rat, i.c.v.), as well as imidazoline I1 /α2 adrenergic receptor agonist, clonidine (2 μg/rat, i.c.v.), I1 agonist moxonidine (25 μg/rat, i.c.v.), and imidazoline I2 agonist, 2-BFI (10 μg/rat, i.c.v.). Conversely, antinociception elicited by ethanol or nicotine or their subeffective dose combination was antagonized by pretreatment with imidazoline I1 antagonist, efaroxan (10 μg/rat, i.c.v.), and I2 antagonist, idazoxan (4 μg/rat, i.c.v.), at their per se ineffective doses. These findings project imidazoline binding ligands as important therapeutic molecules for central antinociceptive activity as well as may reduce the co-abuse potential of alcohol and nicotine.

The effects of alcohol on responses to nicotine-containing and denicotinized cigarettes in dependent and nondaily smokers

BACKGROUND

Alcohol consumption has been linked to increased tobacco use and craving in both dependent and nondaily smokers, yet the extent to which these relationships depend on interactions involving nicotine remains unclear. This study examined the acute effects of alcohol on the subjective and behavioral responses to nicotine-containing tobacco and denicotinized tobacco in 17 (10 male) dependent daily smokers (DDS) and 23 (11 male) nondependent nondaily smokers (NNS).

METHODS

During 4 randomized double-blind sessions, participants assessed the effects of nicotine-containing tobacco or denicotinized tobacco following the administration of a moderately intoxicating dose of alcohol (mean blood alcohol concentration = 0.076 g/dl) or a placebo beverage. They could then self-administer additional puffs of the same type of cigarette sampled over a 60-minute period using a progressive ratio task.

RESULTS

In NNS, alcohol significantly increased the self-administration of both nicotine-containing and denicotinized cigarettes, and no differences in self-administration were observed between the 2 types of tobacco within either beverage condition. In contrast, in DDS, alcohol was associated with decreased denicotinized tobacco self-administration relative to the placebo beverage condition as well as with increased self-administration of nicotine-containing tobacco relative to denicotinized tobacco. DDS also exhibited relatively elevated craving following the administration of a nicotine-containing cigarette in the alcohol beverage condition.

CONCLUSIONS

Findings suggest that nicotine may be critical to the drinking-smoking relationship in DDS, but that nonnicotine smoking factors may be more important in NNS.

Alcohol consumption and urges to smoke among women during a smoking cessation attempt

Laboratory and ad libitum smoking studies have indicated that alcohol consumption increases the frequency and intensity of smoking urges. However, few studies have examined the relation between smoking urges and alcohol use in natural settings during a quit attempt. The purpose of this study was to examine the relationships between smoking urge and alcohol use in women who reported drinking on at least one occasion during the first 7 days of a smoking quit attempt (N = 134). Participants were asked to use a palmtop computer to complete assessments that recorded smoking urges and recent alcohol use. Multilevel analyses examined the relation between smoking urge parameters and alcohol use. Smoking urges were higher during assessments where alcohol had been recently consumed compared to assessments where no alcohol had been consumed. Interestingly, the first urge rating of the day was higher and urges were more volatile on days where alcohol would eventually be consumed as compared to days where no alcohol was consumed. A closer examination of urge parameters on drinking days indicated that smoking urge trajectory was significantly flatter and urge volatility was significantly higher following alcohol consumption. However, smoking urge trajectory also flattened later in the day on nondrinking days. The findings suggest that there may be reciprocal relations between smoking urge and alcohol use (e.g., higher initial urges and more volatile urges may increase the likelihood of alcohol use, and alcohol use may impact within-day smoking urge parameters), and these relations could potentially impact smoking cessation and relapse.

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.

Alternative substance paradigm: effectiveness of beverage blinding and effects on acute alcohol responses

A fundamental goal of double-blind alcohol challenge studies is to reduce alcohol expectancies, though there is little research on the effectiveness of blinding procedures and their relationship to acute alcohol responses. This study examined social drinkers' perception of beverage content and related alcohol response during 3 separate double-blind experimental sessions with placebo, low-dose alcohol (0.4 g/kg), and high-dose alcohol (0.8 g/kg). Using the alternative substance paradigm, participants (N = 182) were informed that the beverage they consumed might contain alcohol, a stimulant, a sedative, or a placebo. At several time points, subjective and objective measures were obtained, and participants were asked to identify which substance they received. During both placebo and low-dose alcohol sessions, 33% and 50% of participants, respectively, did not correctly identify the beverage content; during the high-dose alcohol session, 20% did not correctly identify the beverage. Although correct and incorrect identifiers at any dose level did not differ on major background variables, drinking characteristics, or psychomotor performance during these sessions, they did differ on self-reported subjective responses, with greater sedation reported by incorrect identifiers in the placebo and high-dose conditions. In summary, results suggest that the alternative substance paradigm may be a viable option for alcohol laboratory studies, particularly for repeated sessions in within-subject designs and in cases in which the experimenter wants to reduce expectancy by not revealing a priori that alcohol is being administered.

Responses to alcohol and cigarette use during ecologically assessed drinking episodes

RATIONALE

Tobacco and alcohol are frequently used together, and this may be partly explained by a distinct profile of subjective effects associated with co-administration. Ecological momentary assessment studies have examined effects of naturally occurring co-use, but, to date, have not assessed differing effects as alcohol levels rise and fall.

OBJECTIVES

The objective of the study was to describe subjective states and appraisals of cigarette and alcohol effects reported during the entirety of real-world drinking episodes.

METHODS

Currently-smoking frequent drinkers (N = 255) carried electronic diaries for 21 days. Analyses focused on reports made during 2,046 drinking episodes. Signaled prompts intensively oversampled moments in the hours following consumption of the first drink in an episode. Multilevel regression analyses were used to predict ratings of buzz, dizziness, excitement, and sluggishness as a function of person-level and contextual covariates, estimated blood alcohol concentration (eBAC) level, ascending vs. descending eBAC, smoking, and their interactions. Appraisals of cigarette and alcohol effects were also examined within this framework.

RESULTS

Buzz, excitement, and pleasure from alcohol and cigarettes were prominent features of real-world drinking episodes. Smoking was associated with enhanced buzz and excitement when eBAC was high and descending. Smoking slightly accentuated the relation between eBAC and ratings of drinking pleasure among women, but this relation was somewhat weakened by smoking among men.

CONCLUSIONS

Smoking during drinking episodes may be partly explained by a persistence of stimulant alcohol effects beyond the blood alcohol concentration peak. Acute effects of nicotine and tobacco use on the descending limb deserve further scrutiny in experimental alcohol challenge research.

Sex differences in stimulus expectancy and pharmacologic effects of a moderate dose of alcohol on smoking lapse risk in a laboratory analogue study

RATIONALE

Alcohol use is often implicated in initial lapses to smoking during quit smoking attempts. Mechanisms explaining this association are unknown but could include (a) learned associations between drinking and smoking or (b) direct pharmacologic effects of alcohol.

OBJECTIVES

In a 2 (told alcohol vs. told placebo) × 2 (0.4 g/kg vs. 0.0 g/kg ethanol) between-subjects balanced placebo design, we examined instruction and beverage condition effects on smokers' ability to resist initiating smoking and whether these effects differed by sex.

METHODS

Participants were 96 heavy alcohol drinkers, smoking 10-30 cigarettes per day. After 15 h of smoking abstinence, participants consumed either an alcoholic or a nonalcoholic beverage and 35 min later completed a smoking lapse task.

RESULTS

Overall, neither instructions nor beverage contents influenced behavior on the smoking lapse task. However, the instruction condition had different effects in men and women. Women, but not men, were more likely to smoke and reported expecting greater satisfaction from smoking when they were told alcohol compared to told placebo. The effects of instruction condition on smoking behavior were not mediated by self-reported expected satisfaction from smoking.

CONCLUSIONS

Women may be more likely to choose to smoke after drinking moderate amounts of alcohol because of their expectations rather than the pharmacological effects of the alcohol.

Preliminary findings on the interactive effects of IV ethanol and IV nicotine on human behavior and cognition: a laboratory study

INTRODUCTION

There are mixed reports on nicotine's effects on alcohol-induced impairment in cognitive performance and behavior in humans. The main objective of this study was to characterize the interactive effects of acute intravenous (IV) alcohol and nicotine administration on behavior and cognition in healthy nonsmokers.

METHODS

Healthy subjects aged 21-44 years participated in 3 test days. On each test day, they received in a double-blind randomized manner one of three IV alcohol infusion conditions using a "clamp": placebo, targeted breathalyzer of 40 mg%, or targeted breathalyzer of 80 mg%. Alcohol infusion was delivered over 20 min and lasted for 120 min. They also received both placebo and active nicotine in a fixed order delivered intravenously. Placebo nicotine was delivered first over 10 min at the timepoint when the breath alcohol was "clamped"; active nicotine (1.0 mcg/kg/min) was delivered for 10 min, 70 min after the alcohol infusion was clamped. Subjective effects of alcohol were measured using the Biphasic Alcohol Effects Scale and the Number of Drinks Scale. Cognitive inhibition and attention were measured by the Continuous Performance Task-Identical Pairs and working memory by the Rey Auditory Verbal Learning Task (RAVLT).

RESULTS

Nicotine significantly reversed subjective intoxication and sedation of alcohol at the low dose. Alcohol impaired performance on the RAVLT, and nicotine further impaired verbal learning and recall at both doses of alcohol.

CONCLUSIONS

The data showed that nicotine had an effect on subjective alcohol effects but did not reverse and actually worsened alcohol-induced deficits in memory.

Protein kinase C epsilon modulates nicotine consumption and dopamine reward signals in the nucleus accumbens

Nicotine addiction and alcohol use disorders are very widespread and often occur together. Currently, there is no single drug approved for the simultaneous treatment of both conditions. Although these conditions share common genetic factors, the molecular mechanisms underlying their comorbidity are unknown. We have previously shown that mice lacking protein kinase C epsilon (PKCε) show decreased ethanol self-administration and reward as well as increased aversion to ethanol. Here we find that Prkce(-/-) mice self-administer less nicotine and show decreased conditioned place preference for nicotine compared with wild-type mice. In Prkce(-/-) mice, these behaviors are associated with reduced levels of α(6) and β(3) nicotinic receptor subunit mRNA in the ventral midbrain and striatum as well as a functional deficit in cholinergic modulation of dopamine release in nucleus accumbens. Our results indicate that PKCε regulates reward signaling through α(6)-containing nicotinic receptors and suggest that PKCε could be a target for the treatment of comorbid nicotine and alcohol addictions.

Effects of alcohol on brain responses to social signals of threat in humans

Alcohol is a known exogenous modulator of negative affect (anxiety, tension) in both animals and humans. It has been proposed that the anxiolytic effects of alcohol are mediated via the amygdala, an area critical to fear perception and responding. However, little is known about the acute effects of alcohol on amygdala reactivity to threatening information in humans. We used functional magnetic resonance imaging and a validated task to probe amygdala responses to social signals of threat in 12 healthy, social drinkers after a double-blind crossover administration of alcohol or placebo. We found that alcohol significantly reduced amygdala reactivity to threat signals. The current findings fit well with the notion that alcohol may attenuate threat-based responding and provide a potential brain-based mechanism for the link between alcohol and anxiety and/or social threat perception.

Alcohol expectancy increases positive responses to cigarettes in young, escalating smokers

RATIONALE

A large proportion of smokers consolidate their smoking patterns during young adulthood, and it is possible that the high rates of drinking found in this age group may facilitate the transition from nondaily to daily cigarette use.

OBJECTIVE

The primary aim of this study was to examine how alcohol alters the subjective effects of smoking in heavy-drinking young adults (age 21-25) who are still at an experimental stage of smoking but show recent increases in their smoking behavior.

METHODS

Using a within-subject design, we examined whether alcohol or the expectation of receiving alcohol increased either subjective responses to smoking or the amount smoked. Subjects participated in three sessions, in which they received alcohol (0.08 g/dL targeted blood alcohol level), a taste-masked placebo presented as alcohol, or a mixer beverage not presented as alcohol. Measures included positive and negative subjective reactivity (e.g., satisfaction, nausea, craving relief, and enjoyment of airway sensations) associated with smoking a single cigarette and subsequent ad lib smoking behavior.

RESULTS

Both conditions in which the subjects expected to receive alcohol increased positive effects of smoking (satisfaction, calm, and taste), compared to the mixer beverage. Alcohol, compared to the placebo and mixer beverages, decreased negative effects (nausea) associated with smoking a cigarette and increased subsequent smoking.

CONCLUSIONS

This initial study has implications for understanding how alcohol and the expectation of alcohol improves the experience of smoking in nondaily smokers who are still at an experimental stage of smoking.

Neural substrates of alcohol-induced smoking urge in heavy drinking nondaily smokers

A strong link exists between cigarette smoking and alcohol use, which may be explained by the experimental observation that alcohol ingestion promotes cigarette craving and precipitates smoking. At the neuroanatomic level, it is unclear where and how alcohol exerts these effects, although the process likely involves the ventral striatum given its function in motivational salience and appetitive reinforcement. In a double-blinded, placebo-controlled, crossover study, heavy drinking nondaily social smokers (ie, light smokers or 'chippers') were examined using functional magnetic resonance imaging after they ingested an acute dose of alcohol or placebo. We probed reactivity in the ventral striatum and other brain regions during exposure to visual smoking vs nonsmoking control cues. We found that alcohol enhanced self-reported ratings of desire to smoke, and in this context, significantly increased ventral striatum responses to smoking compared with control cues. In exploratory analyses, we observed that alcohol dampened orbitofrontal activity across both cue types, whereas dorsolateral prefrontal and anterior cingulate cortex activation to smoking cues was not affected by alcohol. This study bridges a pharmacological challenge approach to the study of brain reactivity to smoking cues, extends prior cigarette cue imaging studies to nondependent smokers, and elucidates a potential neurobiological mechanism to explain the co-consumption of alcohol and cigarettes in nondependent users.