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

Sex-specific predictive factors of smoking cessation in subjects at high cardiovascular risk

Smoking is a major risk factor for cardiovascular diseases (CVD), in particular in women, but smoking cessation (SC) reduces or even cancels the risk for both sexes. Using a nationwide SC services database, we aimed to determine the predictive factors of SC in men and women smokers with CV risk factors (CVRF) or CVD. A retrospective study from the French CDTnet database was conducted. Inclusion criteria were age ≥18years, and≥1 CVRF (Body Mass Index ≥25kg/m2, hypertension, diabetes, hypercholesterolemia) or CVD (myocardial infarction (MI) or angina pectoris, stroke, peripheral arterial disease [PAD]). Self-reported smoking abstinence (≥28 consecutive days) was confirmed by exhaled carbon monoxide<10ppm. Logistic regression analysis assessed the association between SC and sociodemographic, medical characteristics, and smoking profile. Among the 36,864 smokers at high CV risk, abstinence rate was slightly lower in women than in men, (52.6% [n=8,102] vs 55.0% [n=11,848], P<0.001). For both sexes, factors associated with the lowest abstinence rates were diabetes, respiratory and psychiatric diseases, anxiolytic/antidepressant use, and cannabis consumption. In women, the factors associated with smoking abstinence were suffering from MI or angina and taking contraceptive pill and the factors associated with persistent smoking were alcohol disorder and high cigarette consumption. In men, there was a positive relationship between overweight and abstinence while being dual users of cigarettes and electronic cigarettes at first visit, having tobacco-related diseases (cancer and PAD) and taking opioid substitution treatment were associated with persistent smoking. Finally, in both sexes, the factors associated with abstinence were: age≥65years, having a diploma, being employed, self-referred or encouraged by entourage, ≥1 previous quit attempt, ≤20 cigarettes per day consumption, benefiting from SC medication prescription and ≥4 follow-up visits. In conclusion, our results suggest the relevance of SC intensive management in smokers at high CV risk, based on sociodemographic, medical, and smoking behaviour characteristics, as well as a gender-specific SC approach.

Supervised machine learning to predict smoking lapses from Ecological Momentary Assessments and sensor data: Implications for just-in-time adaptive intervention development

Specific moments of lapse among smokers attempting to quit often lead to full relapse, which highlights a need for interventions that target lapses before they might occur, such as just-in-time adaptive interventions (JITAIs). To inform the decision points and tailoring variables of a lapse prevention JITAI, we trained and tested supervised machine learning algorithms that use Ecological Momentary Assessments (EMAs) and wearable sensor data of potential lapse triggers and lapse incidence. We aimed to identify a best-performing and feasible algorithm to take forwards in a JITAI. For 10 days, adult smokers attempting to quit were asked to complete 16 hourly EMAs/day assessing cravings, mood, activity, social context, physical context, and lapse incidence, and to wear a Fitbit Charge 4 during waking hours to passively collect data on steps and heart rate. A series of group-level supervised machine learning algorithms (e.g., Random Forest, XGBoost) were trained and tested, without and with the sensor data. Their ability to predict lapses for out-of-sample (i) observations and (ii) individuals were evaluated. Next, a series of individual-level and hybrid (i.e., group- and individual-level) algorithms were trained and tested. Participants (N = 38) responded to 6,124 EMAs (with 6.9% of responses reporting a lapse). Without sensor data, the best-performing group-level algorithm had an area under the receiver operating characteristic curve (AUC) of 0.899 (95% CI = 0.871-0.928). Its ability to classify lapses for out-of-sample individuals ranged from poor to excellent (AUCper person = 0.524-0.994; median AUC = 0.639). 15/38 participants had adequate data for individual-level algorithms to be constructed, with a median AUC of 0.855 (range: 0.451-1.000). Hybrid algorithms could be constructed for 25/38 participants, with a median AUC of 0.692 (range: 0.523 to 0.998). With sensor data, the best-performing group-level algorithm had an AUC of 0.952 (95% CI = 0.933-0.970). Its ability to classify lapses for out-of-sample individuals ranged from poor to excellent (AUCper person = 0.494-0.979; median AUC = 0.745). 11/30 participants had adequate data for individual-level algorithms to be constructed, with a median AUC of 0.983 (range: 0.549-1.000). Hybrid algorithms could be constructed for 20/30 participants, with a median AUC of 0.772 (range: 0.444 to 0.968). In conclusion, high-performing group-level lapse prediction algorithms without and with sensor data had variable performance when applied to out-of-sample individuals. Individual-level and hybrid algorithms could be constructed for a limited number of individuals but had improved performance, particularly when incorporating sensor data for participants with sufficient wear time. Feasibility constraints and the need to balance multiple success criteria in the JITAI development and implementation process are discussed.

Co-action and changes in alcohol use during a smoking cessation attempt

AIMS

Three smoking cessation studies (CARE, Break Free, Por Nuestra Salud [PNS]) were used to measure changes in average alcohol consumption, binge drinking and alcohol-related problems during a smoking cessation attempt and to explore co-action with smoking abstinence.

DESIGN

CARE and PNS were longitudinal cohort cessation studies; Break Free was a two-arm randomized clinical trial.

SETTING

Texas, USA.

PARTICIPANTS

Participants were current smokers who were recruited from the community and received smoking cessation interventions. All participants received nicotine replacement therapy and smoking cessation counseling. CARE included 424 smokers (1/3 White, 1/3 African American and 1/3 Latino); Break Free included 399 African American smokers; PNS included 199 Spanish-speaking Mexican-American smokers.

MEASUREMENTS

Weekly alcohol consumption was collected multiple times pre and post-quit, and binge drinking and alcohol-related problems were collected at baseline and 26 weeks post-quit. Analyses included only those who indicated current alcohol use.

FINDINGS

Average alcohol consumption decreased from baseline to 26 weeks post-quit in CARE (F = 17.09, P < 0.001), Break Free (F = 12.08, P < 0.001) and PNS (F = 10.21, P < 0.001). Binge drinking decreased from baseline to 26 weeks post-quit in CARE (F = 3.94, P = 0.04) and Break Free (F = 10.41, P < 0.001) but not PNS. Alcohol-related problems decreased from baseline to 26 weeks post-quit in CARE (Chi-sq = 6.41, P = 0.010) and Break Free (Chi sq = 14.44, P = 0.001), but not PNS.

CONCLUSIONS

Among current drinkers, alcohol use/problems appear to decrease during a smoking cessation attempt and remain low through 26 weeks after the quit attempt. Little evidence was found for co-action, with smoking abstainers and relapsers showing similar change in alcohol use/problems.

Associations of daily alcohol, cannabis, combustible tobacco, and e-cigarette use with same-day co-use and poly-use of the other substances

BACKGROUND

Young adults frequently use alcohol, cannabis, and tobacco together. Given the increased prevalence of e-cigarette use and recreational cannabis use, we investigated daily patterns of alcohol, cannabis, and tobacco use and distinguished combustible tobacco from e-cigarettes.

METHODS

Young adult college students (N=341) reporting past-month alcohol and cannabis use "at the same time so that their effects overlapped" completed two 28-day bursts of repeated daily surveys. Exposures were day- and person-level use of each substance. Outcomes were (1) same-day co-use of each remaining substance or (2) poly-use of the other substances.

RESULTS

Daily use of alcohol, cannabis, combustible cigarettes, and e-cigarettes increased the odds of same-day co-use of the other substances (except combustible tobacco with e-cigarettes) and each poly-use outcome. The influence of person-level substance use on daily substance use was less consistent. Only e-cigarette use increased the odds of daily alcohol use. Use of either tobacco product but not alcohol increased the odds of daily cannabis use. Person-level alcohol and cannabis use increased the odds of daily use of either tobacco product but use of one tobacco product was not associated with daily use of the other product.

CONCLUSIONS

These findings increase our understanding of emerging daily patterns of alcohol, cannabis, and tobacco co-use, and the impact of different tobacco products. Future work is needed to extend this research into non-college samples and people who use tobacco but do not use alcohol and cannabis simultaneously, and examine daily chronologies of multiple substances that could serve as dynamic markers of risk.

Within-person associations between psychological and contextual factors and lapse incidence in smokers attempting to quit: A systematic review and meta-analysis of ecological momentary assessment studies

AIMS

When attempting to stop smoking, discrete smoking events ('lapses') are strongly associated with a return to regular smoking ('relapse'). No study has yet pooled the psychological and contextual antecedents of lapse incidence, captured in ecological momentary assessment (EMA) studies. This systematic review and meta-analysis aimed to synthesize within-person psychological and contextual predictor-lapse associations in smokers attempting to quit.

METHODS

We searched Ovid MEDLINE, Embase, PsycINFO and Web of Science. A narrative synthesis and multi-level, random-effects meta-analyses were conducted, focusing on studies of adult, non-clinical populations attempting to stop smoking, with no restrictions on setting. Outcomes were the association between a psychological (e.g. stress, cravings) or contextual (e.g. cigarette availability) antecedent and smoking lapse incidence; definitions of 'lapse' and 'relapse'; the theoretical underpinning of EMA study designs; and the proportion of studies with pre-registered study protocols/analysis plans and open data.

RESULTS

We included 61 studies, with 19 studies contributing ≥ 1 effect size(s) to the meta-analyses. We found positive relationships between lapse incidence and 'environmental and social cues' [k = 12, odds ratio (OR) = 4.53, 95% confidence interval (CI) = 2.02, 10.16, P = 0.001] and 'cravings' (k = 10, OR = 1.71, 95% CI = 1.34, 2.18, P < 0.001). 'Negative feeling states' was not significantly associated with lapse incidence (k = 16, OR = 1.10, 95% CI = 0.98, 1.24, P = 0.12). In the narrative synthesis, negative relationships with lapse incidence were found for 'behavioural regulation', 'motivation not to smoke' and 'beliefs about capabilities'; positive relationships with lapse incidence were found for 'positive feeling states' and 'positive outcome expectancies'. Although lapse definitions were comparable, relapse definitions varied widely across studies. Few studies explicitly drew upon psychological theory to inform EMA study designs. One of the included studies drew upon Open Science principles.

CONCLUSIONS

In smokers attempting to stop, environmental and social cues and cravings appear to be key within-person antecedents of smoking lapse incidence. Due to low study quality, the confidence in these estimates is reduced.

Classification of Lapses in Smokers Attempting to Stop: A Supervised Machine Learning Approach Using Data From a Popular Smoking Cessation Smartphone App

INTRODUCTION

Smoking lapses after the quit date often lead to full relapse. To inform the development of real time, tailored lapse prevention support, we used observational data from a popular smoking cessation app to develop supervised machine learning algorithms to distinguish lapse from non-lapse reports.

AIMS AND METHODS

We used data from app users with ≥20 unprompted data entries, which included information about craving severity, mood, activity, social context, and lapse incidence. A series of group-level supervised machine learning algorithms (eg, Random Forest, XGBoost) were trained and tested. Their ability to classify lapses for out-of-sample (1) observations and (2) individuals were evaluated. Next, a series of individual-level and hybrid algorithms were trained and tested.

RESULTS

Participants (N = 791) provided 37 002 data entries (7.6% lapses). The best-performing group-level algorithm had an area under the receiver operating characteristic curve (AUC) of 0.969 (95% confidence interval [CI] = 0.961 to 0.978). Its ability to classify lapses for out-of-sample individuals ranged from poor to excellent (AUC = 0.482-1.000). Individual-level algorithms could be constructed for 39/791 participants with sufficient data, with a median AUC of 0.938 (range: 0.518-1.000). Hybrid algorithms could be constructed for 184/791 participants and had a median AUC of 0.825 (range: 0.375-1.000).

CONCLUSIONS

Using unprompted app data appeared feasible for constructing a high-performing group-level lapse classification algorithm but its performance was variable when applied to unseen individuals. Algorithms trained on each individual's dataset, in addition to hybrid algorithms trained on the group plus a proportion of each individual's data, had improved performance but could only be constructed for a minority of participants.

IMPLICATIONS

This study used routinely collected data from a popular smartphone app to train and test a series of supervised machine learning algorithms to distinguish lapse from non-lapse events. Although a high-performing group-level algorithm was developed, it had variable performance when applied to new, unseen individuals. Individual-level and hybrid algorithms had somewhat greater performance but could not be constructed for all participants because of the lack of variability in the outcome measure. Triangulation of results with those from a prompted study design is recommended prior to intervention development, with real-world lapse prediction likely requiring a balance between unprompted and prompted app data.

Effect of very low nicotine content cigarettes on alcohol drinking and smoking among adult smokers who are at-risk alcohol drinkers

Alcohol and tobacco use are interrelated. This study examined response to very low nicotine content (VLNC) and moderate nicotine content (MNC) cigarettes by problematic drinking. We utilized a double-blind, randomized, within-subjects crossover design of VLNC and MNC cigarettes in two groups of adult cigarette smokers: with at-risk drinking (ARD; n = 23) and without ARD (n = 24). Participants smoked only their assigned experimental cigarette in their home environment for 7 days, and completed laboratory visits, including ad libitum smoking of the assigned experimental cigarette, at the beginning and end of each experimental week. Participants smoked their usual cigarettes for 7 days between conditions. Participants provided daily reports of alcohol and cigarette consumption. Current Diagnostic and Statistical Manual of Mental Disorders-5th edition (DSM-5) alcohol use disorder (AUD) was assessed at baseline and the end of each experimental week. Compliance with smoking of experimental cigarettes was good. Adjusting for baseline drinking, there was no significant effect of experimental cigarette or ARD group on drinks per day or alcohol urges. There was no effect of experimental cigarette or ARD group on cigarettes per day, or on any puff topography outcome or postsmoking exhaled carbon monoxide during laboratory smoking. No participant had a change in AUD status or AUD severity. After 7 days of exposure to VLNC cigarettes, adult cigarette smokers with ARD did not show compensatory drinking or compensatory smoking behavior. A future policy change in the United States to reduce nicotine content in cigarettes may not produce unintended compensatory drinking or smoking among this vulnerable and prevalent population of smokers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

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.

Technology-mediated just-in-time adaptive interventions (JITAIs) to reduce harmful substance use: a systematic review

BACKGROUND AND AIMS

Lapse risk when trying to stop or reduce harmful substance use is idiosyncratic, dynamic and multi-factorial. Just-in-time adaptive interventions (JITAIs) aim to deliver tailored support at moments of need or opportunity. We aimed to synthesize evidence on decision points, tailoring variables, intervention options, decision rules, study designs, user engagement and effectiveness of technology-mediated JITAIs for reducing harmful substance use.

METHODS

Systematic review of empirical studies of any design with a narrative synthesis. We searched Ovid MEDLINE, Embase, PsycINFO, Web of Science, the ACM Digital Library, the IEEE Digital Library, ClinicalTrials.gov, the ISRCTN register and dblp using terms related to substance use/mHealth/JITAIs. Outcomes were user engagement and intervention effectiveness. Study quality was assessed with the mHealth Evidence Reporting and Assessment checklist.

FINDINGS

We included 17 reports of 14 unique studies, including two randomized controlled trials. JITAIs targeted alcohol (S = 7, n = 120 520), tobacco (S = 4, n = 187), cannabis (S = 2, n = 97) and a combination of alcohol and illicit substance use (S = 1, n = 63), and primarily relied on active measurement and static (i.e. time-invariant) decision rules to deliver support tailored to micro-scale changes in mood or urges. Two studies used data from prior participants and four drew upon theory to devise decision rules. Engagement with available JITAIs was moderate-to-high and evidence of effectiveness was mixed. Due to substantial heterogeneity in study designs and outcome variables assessed, no meta-analysis was performed. Many studies reported insufficient detail on JITAI infrastructure, content, development costs and data security.

CONCLUSIONS

Current implementations of just-in-time adaptive interventions (JITAIs) for reducing harmful substance use rely on active measurement and static decision rules to deliver support tailored to micro-scale changes in mood or urges. Studies on JITAI effectiveness are lacking.

Quit Stage and Intervention Type Differences in the Momentary Within-Person Association Between Negative Affect and Smoking Urges

Background

Smoking urges and negative affect play important roles in daily cigarette smoking and smoking lapse during a cessation attempt. Traditionally, laboratory research has considered negative affect as a potential cause of smoking urges. A deeper understanding of momentary associations between negative affect and smoking urges during a smoking cessation attempt can inform treatment development efforts. This study examined whether the within-person association between negative affect and smoking urges differed before and after a quit attempt, and by intervention type.

Methods

Data are from a pilot randomized controlled trial comparing 3 smoking cessation interventions. Participants were randomly assigned to: (1) a novel, smartphone-based just-in-time adaptive intervention that tailored treatment content in real-time (Smart-T2; n = 24), (2) the National Cancer Institute QuitGuide app (n = 25), or (3) a clinic-based tobacco cessation program (TTRP; n = 23) that followed Clinical Practice Guidelines. All participants received up to 12 weeks of nicotine replacement therapy and completed up to 5 assessments per day (M PreQuit = 25.8 assessments, SD = 6.0; M PostQuit = 107.7 assessments, SD = 37.1) of their negative affect and smoking urges during the 7 days (M = 6.6 days, SD = 1.0) prior to their quit-date and the 29 days (M = 25.8 days, SD = 6.4) after their quit-date. Prior to analysis, repeated measures of smoking urges were decomposed into between-person and within-person components.

Results

After accounting for baseline nicotine dependence, Bayesian multilevel models indicated that the extent of within-person association between negative affect and smoking urges was stronger in the post-quit stage of the intervention than the pre-quit stage. Results also indicated that in the post-quit stage of the intervention, the within-person association between negative affect and smoking urges was weaker for those in the Smart-T2 and TTRP groups compared with those in the QuitGuide group. The extent of this within-person association did not differ between those in the Smart-T2 and TTRP groups.

Conclusions

These findings offer preliminary evidence that the momentary within-person association between negative affect and smoking urges increases following a quit attempt, and that the TTRP and Smart-T2 interventions may weaken this association. Research is needed to replicate and expand upon current findings in a fully powered randomized controlled trial.

Clinical Trial Registration

ClinicalTrials.gov NCT02930200; https://clinicaltrials.gov/show/NCT02930200.

The relations between discrimination, stressful life events, and substance use among adults experiencing homelessness

The current study investigated whether stressful life events and everyday discrimination experiences were associated with using one or more substances in the past 30-days and substance use disorder (SUD) among adults experiencing homelessness. We obtained survey data from adults (N = 501) seeking services at a day shelter. Participants self-reported whether they used cigarettes, other tobacco products, cannabis, alcohol, opioids, amphetamine, and cocaine/crack in the past 30-days, and the total number of substances used were also calculated. We measured stressful life events and everyday discrimination using validated scales. We used multivariable logistic and negative binomial regression analyses to evaluate hypothesised associations. Results indicated that reporting a higher number of stressful life events was associated with past 30-days cannabis, tobacco, alcohol, and other substance use, screening positive for a SUD, and using a greater number of substances in the past 30 days. After accounting for stressful life events, everyday discrimination was associated with only past 30-days cannabis use. Overall, we found that reporting stressful life events was related to current substance use and screening positive for a SUD. Findings suggest that life stressors, and discrimination to a lesser extent, were associated with substance use and SUD among adults experiencing homelessness.

The impact of adolescent nicotine exposure on alcohol use during adulthood: The role of neuropeptides

Nicotine and alcohol abuse and co-dependence represent major public health crises. Indeed, previous research has shown that the prevalence of alcoholism is higher in smokers than in non-smokers. Adolescence is a susceptible period of life for the initiation of nicotine and alcohol use and the development of nicotine-alcohol codependence. However, there is a limited number of pharmacotherapeutic agents to treat addiction to nicotine or alcohol alone. Notably, there is no effective medication to treat this comorbid disorder. This chapter aims to review the early nicotine use and its impact on subsequent alcohol abuse during adolescence and adulthood as well as the role of neuropeptides in this comorbid disorder. The preclinical and clinical findings discussed in this chapter will advance our understanding of this comorbid disorder's neurobiology and lay a foundation for developing novel pharmacotherapies to treat nicotine and alcohol codependence.

The mobile assistance for regulating smoking (MARS) micro-randomized trial design protocol

Smoking is the leading preventable cause of death and disability in the U.S. Empirical evidence suggests that engaging in evidence-based self-regulatory strategies (e.g., behavioral substitution, mindful attention) can improve smokers' ability to resist craving and build self-regulatory skills. However, poor engagement represents a major barrier to maximizing the impact of self-regulatory strategies. This paper describes the protocol for Mobile Assistance for Regulating Smoking (MARS) - a research study designed to inform the development of a mobile health (mHealth) intervention for promoting real-time, real-world engagement in evidence-based self-regulatory strategies. The study will employ a 10-day Micro-Randomized Trial (MRT) enrolling 112 smokers attempting to quit. Utilizing a mobile smoking cessation app, the MRT will randomize each individual multiple times per day to either: (a) no intervention prompt; (b) a prompt recommending brief (low effort) cognitive and/or behavioral self-regulatory strategies; or (c) a prompt recommending more effortful cognitive or mindfulness-based strategies. Prompts will be delivered via push notifications from the MARS mobile app. The goal is to investigate whether, what type of, and under what conditions prompting the individual to engage in self-regulatory strategies increases engagement. The results will build the empirical foundation necessary to develop a mHealth intervention that effectively utilizes intensive longitudinal self-report and sensor-based assessments of emotions, context and other factors to engage an individual in the type of self-regulatory activity that would be most beneficial given their real-time, real-world circumstances. This type of mHealth intervention holds enormous potential to expand the reach and impact of smoking cessation treatments.

Factors Associated with the 30-Day and 1-Year Smoking Abstinence of Women in Korea: The Effect of Nicotine Dependency, Self-Efficacy, and Mental Illness

Despite the success of tobacco control efforts in reducing smoking rates during the past 50 years, data on the factors contributing to quitting success are still lacking. Smoking-related mortality among women has also not declined. Therefore, this study aimed to characterize sociodemographic features, smoking-related behaviors, mental illness, and smoking cessation in woman smokers in Korea who were registered in the Quitline program. Furthermore, factors associated with 30-day and 1-year successful smoking cessation after enrollment in the Quitline program were investigated. A total of 3360 adult woman Quitline users from 2007 to 2018 were included in the final analysis, with information on their age, education level, marital status, body mass index, frequency of alcohol consumption per month, nicotine dependency, self-efficacy for smoking cessation, presence of a smoking cessation supporter, and mental health history collected upon registration with the Quitline program in Korea. Their cessation outcome was investigated with a 1-year follow-up until the end of 2019. A multiple logistic regression analysis was conducted to identify factors associated with smoking cessation at the 30-day and 1-year follow-ups. The results of the multiple logistic regression analysis indicated that lower nicotine dependency, higher self-efficacy, and the presence of a smoking cessation supporter improved the odds of smoking cessation at the 30-day and 1-year follow-ups. In contrast, users with a mental health condition were less likely to achieve smoking cessation. Incorporating methods to increase self-efficacy in women who decide to quit smoking will contribute to facilitating more attempts to quit and achieving greater success in smoking cessation among woman smokers.

Alterations of Amphetamine Reward by Prior Nicotine and Alcohol Treatment: The Role of Age and Dopamine

Evidence suggests that nicotine and alcohol can each serve as a gateway drug. We determined whether prior nicotine and alcohol treatment would alter amphetamine reward. Also, we examined whether age and dopaminergic neurotransmission are important in this regard. Male and female adolescent and adult C57BL/6J mice were tested for baseline place preference. Mice then received six conditioning with saline/nicotine (0.25 mg/kg) twice daily, followed by six conditioning with saline/ethanol (2 g/kg). Control mice were conditioned with saline/saline throughout. Finally, mice were conditioned with amphetamine (3 mg/kg), once in the nicotine-alcohol-paired chamber, and tested for place preference 24 h later. The following day, mice were challenged with amphetamine (1 mg/kg) and tested for place preference under a drugged state. Mice were then immediately euthanized, their brain removed, and nucleus accumbens isolated and processed for the level of dopamine receptors and transporter and glutamate receptors. We observed a greater amphetamine-induced place preference in naïve adolescents than adult mice with no change in state-dependent place preference between the two age groups. In contrast, amphetamine induced a significant place preference in adult but not adolescent mice with prior nicotine-alcohol exposure under the drug-free state. The preference was significantly greater in adults than adolescents under the drugged state. The enhanced response was associated with higher dopamine-transporter and D₁ but reduced D₂ receptors’ expression in adult rather than adolescent mice, with no changes in glutamate receptors levels. These results suggest that prior nicotine and alcohol treatment differentially alters amphetamine reward in adult and adolescent mice. Alterations in dopaminergic neurotransmission may be involved in this phenotype.

Concurrent Alcohol Use and Waterpipe Tobacco Smoking: Smoking Topography, Toxicant Exposure, and Abuse Liability

INTRODUCTION

Relative to non-waterpipe (WP) smokers, WP smokers are more than twice as likely to use alcohol and frequently consume alcohol before or during smoking sessions. Co-use of alcohol and WP may result in greater toxicant exposure compared to WP smoking alone. To date, no study systematically has investigated the impact of acute alcohol intoxication on WP smoking topography, exposure to tobacco-related toxicants, or abuse liability.

METHODS

Dyads of current WP smokers and drinkers (N = 42; age = 21-32 years) completed two in-laboratory ad libitum smoking sessions (≤2 hours) following 12-hour nicotine abstinence in a double-blind, randomized crossover design in which they consumed a placebo versus active drink (sustained breath alcohol concentration = .08). Exhaled carbon monoxide (eCO) and plasma nicotine concentration were assessed. Questionnaires assessed smoking experience and smoking urge. Smoking topography was measured continuously throughout each smoking session.

RESULTS

The alcohol session was associated with increased inhaled volume, flow rate, and WP session duration compared to placebo. Compared to placebo, participants reported a more positive overall smoking experience following the alcohol session and greater smoking urges pre- and post-smoking session. Although both sessions resulted in significant increases in eCO and plasma nicotine, no significant differences emerged in eCO or nicotine exposure between the active and placebo sessions.

CONCLUSIONS

Co-use of alcohol and WP may contribute to the maintenance of WP smoking through enhanced smoking experiences, increased urge to smoke, and significant exposure to addictive nicotine. Regulations may be necessary to limit the sale of alcohol in WP smoking lounges and reduce exposure to secondhand smoke.

IMPLICATIONS

The findings suggest co-use of alcohol and WP tobacco likely maintain WP use and dependence by enhancing the smoking experience and increasing urges to smoke. These findings have implications for regulations aimed at limiting co-use of alcohol and WP tobacco in WP lounges and limiting exposure to secondhand smoke.

CLINICAL TRIALS REGISTRATION

NCT03096860.

Identifying Behaviors Predicting Early Morning Emotions by Observing Permanent Supportive Housing Residents: An Ecological Momentary Assessment

BACKGROUND

Behavior and emotions are closely intertwined. The relationship between behavior and emotions might be particularly important in populations of underserved people, such as people with physical or mental health issues. We used ecological momentary assessment (EMA) to examine the relationship between emotional state and other characteristics among people with a history of chronic homelessness who were participating in a health coaching program.

OBJECTIVE

The goal of this study was to identify relationships between daily emotional states (valence and arousal) shortly after waking and behavioral variables such as physical activity, diet, social interaction, medication compliance, and tobacco usage the prior day, controlling for demographic characteristics.

METHODS

Participants in m.chat, a technology-assisted health coaching program, were recruited from housing agencies in Fort Worth, Texas, United States. All participants had a history of chronic homelessness and reported at least one mental health condition. We asked a subset of participants to complete daily EMAs of emotions and other behaviors. From the circumplex model of affect, the EMA included 9 questions related to the current emotional state of the participant (happy, frustrated, sad, worried, restless, excited, calm, bored, and sluggish). The responses were used to calculate two composite scores for valence and arousal.

RESULTS

Nonwhites reported higher scores for both valence and arousal, but not at a statistically significant level after correcting for multiple testing. Among momentary predictors, greater time spent in one-on-one interactions, greater time spent in physical activities, a greater number of servings of fruits and vegetables, greater time spent interacting in a one-on-one setting as well as adherence to prescribed medication the previous day were generally associated with higher scores for both valence and arousal, and statistical significance was achieved in most cases. Number of cigarettes smoked the previous day was generally associated with lower scores on both valence and arousal, although statistical significance was achieved for valence only when correcting for multiple testing.

CONCLUSIONS

This study provides an important glimpse into factors that predict morning emotions among people with mental health issues and a history of chronic homelessness. Behaviors considered to be positive (eg, physical activity and consumption of fruits and vegetables) generally enhanced positive affect and restrained negative affect the following morning. The opposite was true for behaviors such as smoking, which are considered to be negative.

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.

Demographic, Healthcare, and Contextual Factors Associated with Smoking Status Among Sexual Minority Women

PURPOSE

The study purpose was to examine demographic, healthcare, and contextual correlates of smoking among sexual minority women (SMW).

METHODS

Data were from the Chicago Health and Life Experiences of Women study (2010-2012, N = 726).

RESULTS

The rate of current smoking was 29.6%, with 29.5% and 40.9% former or nonsmokers, respectively. A history of ever smoking was associated with lower educational levels, having a partner who smokes, heavy drinking, illicit drug use, and a bisexual identity. Statistically significant correlates of former versus current smoker included higher education, having a nonsmoking partner, being from the newest recruited cohort, and less illicit drug use. A past-year quit attempt among current smokers was associated with higher levels of illicit drug use, longer time until first cigarette, and being from the original cohort.

CONCLUSION

The study results highlight key correlates of smoking behaviors among SMW and make an important contribution to the literature on smoking disparities. Additional research is needed to inform smoking cessation prevention and control efforts to reduce known and persistent smoking disparities among SMW.

Nicotine pretreatment reduced cocaine-induced CPP and its reinstatement in a sex- and dose-related manner in adult C57BL/6J mice

Previous preclinical studies have shown that nicotine pretreatment during adolescence increases the reinforcing actions of cocaine. However, little is known about the effect of prior nicotine administration on cocaine-induced conditioned place preference (CPP) and its reinstatement in adult mice. Besides, little information is available regarding the role of sex in this cross-talk between nicotine and cocaine. Thus, we examined if nicotine administration during adulthood would differentially alter cocaine-induced CPP, its extinction and reinstatement in male versus female mice and if the dose of nicotine was important in this regard. To this end, mice were pretreated with saline or nicotine (0.25 or 1mg/kg; twice daily for seven days) and then tested for place preference before and after single and repeated conditioning with cocaine (15mg/kg). Mice were then exposed to extinction training and tested for reinstatement of CPP. Our results showed that male and female mice pretreated with saline and conditioned with cocaine each exhibited a robust CPP after a single cocaine conditioning. However, this response was blunted in mice pretreated with the lower but not higher dose of nicotine. Female mice pretreated with the lower dose nicotine also failed to show CPP after repeated conditioning. Reinstatement of cocaine-induced CPP was also blunted in these mice compared to their respective controls. Together, these results suggest that nicotine administration during adulthood exerts differential effects on cocaine-induced CPP and its reinstatement in male and female mice and the dose of nicotine is important in this regard.

Combination of ALDH2 and ADH1B polymorphisms is associated with smoking initiation: A large-scale cross-sectional study in a Japanese population

BACKGROUND

Aldehyde dehydrogenase 2 (ALDH2; rs671, Glu504Lys) and alcohol dehydrogenase 1B (ADH1B; rs1229984, His47Arg) polymorphisms are known to strongly influence alcohol　drinking behavior. Given evidence of an association between smoking and drinking behaviors, we hypothesized that ALDH2/ADH1B polymorphisms might also be associated with smoking initiation, and conducted a cross-sectional study to examine this hypothesis.

METHODS

Study subjects were first-visit outpatients diagnosed not to have cancer at Aichi Cancer Center Hospital between 2001 and 2005, including 4141 never smokers and 2912 ever smokers. Unconditional logistic regression models were applied to estimate odds ratios (OR) and 95% confidence intervals (CI) for smoking initiation by comparing ever smokers with never smokers.

RESULTS

Excessive alcohol drinking was associated with a higher likelihood of ever smoking. After adjustment for drinking behaviors, compared to individuals with ALDH2 Glu/Glu, the ORs of ever smoking were 1.71 (95% CI, 1.49-1.95) and 2.28 (1.81-2.87) among those with ALDH2 Glu/Lys and Lys/Lys, respectively. Combination of ALDH2 Lys/Lys and ADH1B His/His (i.e., the most alcohol-intolerant subpopulation) showed the highest OR [2.44 (1.84-3.23)], whereas combination of ALDH2 Glu/Glu and ADH1B Arg/Arg (i.e., the most alcohol-tolerant subpopulation) showed the lowest OR [0.83 (0.57-1.21)] compared with ALDH2 Glu/Glu and ADH1B His/His.

CONCLUSION

Besides the amount and frequency of alcohol drinking, the combination of ALDH2 and ADH1B polymorphisms predicts smoking initiation. This study suggests that alcohol tolerance regulated by ALDH2 and ADH1B polymorphisms is associated with smoking initiation, and facilitates the development of targeted interventions to reduce smoking prevalence.

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.

An Ecological Momentary Intervention for Smoking Cessation: Evaluation of Feasibility and Effectiveness

BACKGROUND

Despite substantial public health progress in reducing the prevalence of smoking in the United States overall, smoking among socioeconomically disadvantaged adults remains high.

OBJECTIVE

To determine the feasibility and preliminary effectiveness of a novel smartphone-based smoking cessation app designed for socioeconomically disadvantaged smokers.

METHODS

Participants were recruited from a safety-net hospital smoking cessation clinic in Dallas, Texas, and were followed for 13 weeks. All participants received standard smoking cessation clinic care (ie, group counseling and cessation pharmacotherapy) and a smartphone with a novel smoking cessation app (ie, Smart-T). The Smart-T app prompted 5 daily ecological momentary assessments (EMAs) for 3 weeks (ie, 1 week before cessation and 2 weeks after cessation). During the precessation period, EMAs were followed by messages that focused on planning and preparing for the quit attempt. During the postcessation period, participant responses to EMAs drove an algorithm that tailored messages to the current level of smoking lapse risk and currently present lapse triggers (eg, urge to smoke, stress). Smart-T offered additional intervention features on demand (eg, one-click access to the tobacco cessation quitline; "Quit Tips" on coping with urges to smoke, mood, and stress).

RESULTS

Participants (N=59) were 52.0 (SD 7.0) years old, 54% (32/59) female, and 53% (31/59) African American, and 70% (40/57) had annual household income less than US $16,000. Participants smoked 20.3 (SD 11.6) cigarettes per day and had been smoking for 31.6 (SD 10.9) years. Twelve weeks after the scheduled quit date, 20% (12/59) of all participants were biochemically confirmed abstinent. Participants responded to 87% of all prompted EMAs and received approximately 102 treatment messages over the 3-week EMA period. Most participants (83%, 49/59) used the on-demand app features. Individuals with greater nicotine dependence and minority race used the Quit Tips feature more than their counterparts. Greater use of the Quit Tips feature was linked to nonabstinence at the 2 (P=.02), 4 (P<.01), and 12 (P=.03) week follow-up visits. Most participants reported that they actually used or implemented the tailored app-generated messages and suggestions (83%, 49/59); the app-generated messages were helpful (97%, 57/59); they would like to use the app in the future if they were to lapse (97%, 57/59); and they would like to refer friends who smoke to use the Smart-T app (85%, 50/59). A minority of participants (15%, 9/59) reported that the number of daily assessments (ie, 5) was "too high."

CONCLUSIONS

This novel just-in-time adaptive intervention delivered an intensive intervention (ie, 102 messages over a 3-week period), was well-liked, and was perceived as helpful and useful by socioeconomically disadvantaged adults who were seeking smoking cessation treatment. Smartphone apps may be used to increase treatment exposure and may ultimately reduce tobacco-related health disparities among socioeconomically disadvantaged adults.

The Association of Pain With Smoking and Quit Attempts in an Electronic Diary Study of Cancer Patients Trying to Quit

INTRODUCTION

The purpose of this electronic daily diary study was to examine the relation of pain to smoking and quit attempts among 34 cancer patients with pain enrolled in a smoking cessation program.

METHODS

Electronic daily diary assessments of pain and smoking were collected at the end of each day for a 2-week period during smoking cessation treatment. Pain experienced throughout the day was measured on a scale from 1 to 5, from "no pain" to "pain as bad as you can imagine." Smoking was defined as the number of cigarettes smoked per day.

RESULTS

Linear multilevel modeling was used in examining associations between pain and smoking. A within-person pain and smoking association was found, such that greater daily pain was linked to greater daily smoking within individuals, controlling for baseline symptoms, nicotine dependence, smoking urge, age, and gender. No between-person pain and smoking association was observed. Additionally, cancer patients with higher average pain across the 2-week assessment period were less likely to make a quit attempt (defined as a day on which participants smoked no cigarettes) during the study period.

CONCLUSIONS

The findings of this study add to a nascent literature on pain and smoking by providing initial evidence that pain may be a barrier to quitting among cancer patients who smoke and have pain. Future research examining the effectiveness of integrated pain and smoking cessation treatment in this population may be warranted.

Ecological momentary assessment in the investigation of craving and substance use in daily life: a systematic review

BACKGROUND

Craving is viewed as a major determinant of relapse in persons with substance addiction, but this association remains poorly understood due to its time-limited nature and the biases associated with retrospective reporting. Ecological momentary assessment (EMA) offers new opportunities to examine both craving and substance use with strong ecological validity by collecting real-time data in daily life. This review examined all published studies using EMA to: (1) assess the link between craving and substance use; and (2) identify relevant moderators of craving among substance users.

METHODS

We searched PubMed and PsycInfo databases up to October 31, 2013.

RESULTS

Ninety-one studies were selected, involving mostly tobacco smokers (73%). A majority of studies (92%) reported a positive relationship between craving and substance use, concurrently and prospectively, and among users with different levels of use for both legal and illegal substances. Results suggest that craving is a stronger predictor of relapse episodes when assessed in close temporal proximity to substance use. EMA data also confirmed the influence of diverse within-person and between-person sources of variation in daily life craving reports.

CONCLUSIONS

This review provides strong support for the link between craving and substance use, and underscores the importance of the timing of assessments.

Acute effects of low and high dose alcohol on smoking lapse behavior in a laboratory analogue task

RATIONALE

Smoking lapses (i.e., returns to smoking after quitting) often occur following alcohol consumption with observational data suggesting greater quantities of alcohol lead to greater risk. However, a causal dose-dependent effect of alcohol consumption on smoking lapse behavior has not been established, and the mechanisms that might account for such an effect have not been tested.

OBJECTIVES

In a within-subjects design, we examined the effects of low- (0.4 g/kg) and high-dose (0.8 g/kg) alcohol, relative to placebo, on smokers' ability to resist initiating smoking after acute smoking abstinence.

METHODS

Participants were 100 heavy alcohol drinkers, smoking 10-30 cigarettes per day. Across three separate days, participants consumed placebo, low-dose, or high-dose alcohol following 3 h of smoking abstinence and, 35 min later, were offered the opportunity to smoke while resisting smoking was monetarily reinforced proportional to the amount of time delayed.

RESULTS

Consistent with a dose-response effect, participants smoked 3.35 min (95 % confidence intervals (CI) [-7.09, 0.40], p = .08) earlier following low-dose alcohol and 6.36 min (95 % CI [-9.99, -2.73], p = .0006) earlier following high-dose alcohol compared to drinking a placebo beverage. Effects of dose on smoking behavior were partially mediated by increases in urge to smoke. There was no evidence that alcohol's effects on urge to smoke or ability to resist smoking were mediated through its stimulating or sedating effects.

CONCLUSIONS

Alcohol can reduce the ability to resist smoking in a dose-dependent fashion, in part, due to its effect on increasing the intensity of smoking urges.

Predicting quit attempts among homeless smokers seeking cessation treatment: an ecological momentary assessment study

INTRODUCTION

Homeless adults are more likely to smoke tobacco and are less likely to successfully quit smoking than smokers in the general population, despite comparable numbers of cessation attempts and desire to quit. To date, studies that have examined smoking cessation in homeless samples have used traditional lab/clinic-based assessment methodologies. Real-time assessment of key variables may provide new insights into the process of quitting among homeless smokers.

METHODS

The purpose of the current study was to identify predictors of a quit attempt using real-time assessment methodology during the 6 days prior to a scheduled quit attempt among homeless adults seeking care at a shelter-based smoking cessation clinic. Parameters for multiple variables (i.e., motivation for quitting, smoking expectancies, quit self-efficacy, smoking urges, negative affect, positive affect, restlessness, hostility, and stress) were calculated and were used as predictors of biochemically verified quit date abstinence (i.e., ≥13hr abstinent) using logistic regression analyses.

RESULTS

Participants (n = 57) were predominantly male (59.6%), non-White (68.4%), and smoked an average of 18 cigarettes per day. A total of 1,132 ecological momentary assessments (83% completion rate) were collected at random times (i.e., up to 4 assessments/day) during the 6 days prior to a scheduled quit attempt. Results indicated that declining (negative slope) negative affect, restlessness, and stress predicted quit date abstinence. Additionally, increasing positive coping expectancies across the prequit week predicted quit date abstinence.

CONCLUSIONS

Study findings highlight multiple variables that may be targeted during the precessation period to increase smoking cessation attempts in this difficult to treat population of 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.

Nicotine Blocks the Depressogenic Effects of Alcohol: Implications for Drinking-Smoking Co-Morbidity

Alcohol and nicotine are two very commonly abused legal substances. Although various hypotheses for such co-dependence have been suggested, it is not known whether the effects of alcohol and nicotine on mood behavior may also contribute to such co-abuse. Chronic exposure to high alcohol levels may lead to various neurochemical changes and precipitate depressive-like behavior. Nicotine, on the other hand, may exert an antidepressant-like effect. Here, we sought to determine whether nicotine may also block or mitigate the "depressogenic" effects of alcohol in a rat model. Moreover, since hippocampal brain-derived neurotrophic factor (BDNF) has been strongly implicated in mood regulation and effectiveness of antidepressants, the level of this neurotrophic factor in the hippocampus was also evaluated. Adult male Wistar rats were injected (i.p.) with alcohol (1.0 g/kg), nicotine (0.3 mg/kg) or their combination once daily for 14 days. Controls received saline. The behavior of these rats in open field locomotor activity (LMA), the forced swim test (FST), a measure of helplessness, and sucrose intake, a measure of anhedonia were evaluated 16-18 h after the last injection. Chronic alcohol did not affect LMA, but increased immobility in FST and decreased sucrose consumption, suggesting a "depressogenic" effect. Nicotine by itself did not affect any of the measured behavior but blocked alcohol-induced changes in FST and sucrose intake. Parallel to the behavioral changes, chronic alcohol resulted in a significant decrease in hippocampal BDNF, which was normalized by nicotine. These findings suggest that the opposing effects of alcohol and nicotine on depressive-like behavior may contribute to their co-abuse.