Differential rates of relapse in subgroups of male and female smokers

Hypothalamic pituitary adrenal and autonomic nervous system biomarkers of stress and tobacco relapse: Review of the research

Tobacco smoking is a risk factor for countless diseases, and smoking relapse remains a major public health concern. Subjective reports of stress by smokers are a common theme for relapse, however, the role of objective stress-related biomarkers in predicting tobacco relapse risk has been less studied. The aim of this manuscript was to review existing literature on the connection between biomarkers of stress and smoking relapse. Overall, trends indicate that blunted hypothalamic-pituitary-adrenal (HPA) responses to acute stress, larger reductions in HPA biomarkers during the initial days of abstinence during cessation (compared to pre-cessation levels), and exaggerated autonomic responses to stress predict increased risk of relapse. In addition, successful cessation is followed by changes in stress biomarkers (e.g., reductions in cortisol and heart rate, HR). This review also identifies potential modifiers, such as methodological differences, biological sex, and chronic stress, to account for heterogeneity of findings within and across studies. In addition, we identify gaps in the literature and suggest future research directions focusing on the roles of genetics and gene expression as well as the influence of neurobiological mechanisms on stress and relapse risk. Future clinical implications of this research include identifying reliable indicators of relapse risk and the potential of pharmacotherapeutic treatments to target stress response systems to correct dysregulation and potentially reduce stress-related risk of relapse.

Targeting GLP-1 receptors to reduce nicotine use disorder: Preclinical and clinical evidence

Nicotine use disorder (NUD) remains a leading cause of preventable death in the U.S. Unfortunately, current FDA-approved pharmacotherapies for smoking cessation have limited efficacy and are associated with high rates of relapse. One major barrier to long-term smoking abstinence is body weight gain during withdrawal. Nicotine withdrawal-induced body weight gain can also lead to development of chronic disease states like obesity and type II diabetes mellitus. Therefore, it is critical to identify novel pharmacotherapies for NUD that decrease relapse and nicotine withdrawal symptoms including body weight gain. Recent studies demonstrate that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate voluntary nicotine taking and seeking and prevent withdrawal-induced hyperphagia and body weight gain. Emerging evidence also suggests that GLP-1R agonists improve cognitive deficits, as well as depressive- and anxiety-like behaviors, which contribute to smoking relapse during withdrawal. While further studies are necessary to fully characterize the effects of GLP-1R agonists on NUD and understand the mechanisms by which GLP-1R agonists decrease nicotine withdrawal-mediated behaviors, the current literature supports GLP-1R-based approaches to treating NUD.

Extracellular ATP Neurotransmission and Nicotine Sex-Specifically Modulate Habenular Neuronal Activity in Adolescence

The recent increase in the use of nicotine products by teenagers has revealed an urgent need to better understand the impact of nicotine on the adolescent brain. Here, we sought to examine the actions of extracellular ATP as a neurotransmitter and to investigate whether ATP and nicotinic signaling interact during adolescence. With the GRABATP (G-protein-coupled receptor activation-based ATP sensor), we first demonstrated that nicotine induces extracellular ATP release in the medial habenula, a brain region involved in nicotine aversion and withdrawal. Using patch-clamp electrophysiology, we then demonstrated that activation of the ATP receptors P2X or P2Y1 increases the neuronal firing of cholinergic neurons. Surprisingly, contrasting interactive effects were observed with nicotine exposure. For the P2X receptor, activation had no observable effect on acute nicotine-mediated activity, but during abstinence after 10 d of nicotine exposure, coexposure to nicotine and the P2X agonist potentiated neuronal activity in female, but not male, neurons. For P2Y1 signaling, a potentiated effect of the agonist and nicotine was observed with acute exposure, but not following extended nicotine exposure. These data reveal a complex interactive effect between nicotinic and ATP signaling in the adolescent brain and provide mechanistic insights into extracellular ATP signaling with sex-specific alterations of neuronal responses based on prior drug exposure.SIGNIFICANCE STATEMENT In these studies, it was discovered that nicotine induces extracellular ATP release in the medial habenula and subsequent activation of the ATP purinergic receptors increases habenular cholinergic neuronal firing in the adolescent brain. Interestingly, following extended nicotine exposure, nicotine was found to alter the interplay between purinergic and nicotinic signaling in a sex-specific manner. Together, these studies provide a novel understanding for the role of extracellular ATP in mediating habenular activity and reveal how nicotine exposure during adolescence alters these signaling mechanisms, which has important implications given the high incidence of e-cigarette/vape use by youth.

Oral Contraceptives and Cigarette Smoking: A Review of the Literature and Future Directions

INTRODUCTION

Evidence continues to mount indicating that endogenous sex hormones (eg, progesterone and estradiol) play a significant role in smoking-related outcomes. Although approximately one out of four premenopausal smokers use oral contraceptives (OCs), which significantly alter progesterone and estradiol levels, relatively little is known about how OCs may influence smoking-related outcomes. Thus, the goal of this review article is to describe the state of the literature and offer recommendations for future directions.

METHODS

In March 2017, we searched seven databases, with a restriction to articles written in English, using the following keywords: nicotine, smoker(s), smoking, tobacco, cigarettes, abstinence, withdrawal, and craving(s). We did not restrict on the publication date, type, or study design.

RESULTS

A total of 13 studies were identified. Three studies indicated faster nicotine metabolism in OC users compared to nonusers. Five of six laboratory studies that examined physiological stress response noted heightened response in OC users compared to nonusers. Three studies examined cessation-related symptomatology (eg, craving) with mixed results. One cross-sectional study observed greater odds of current smoking among OC users, and no studies have explored the relationship between OC use and cessation outcomes.

CONCLUSIONS

Relatively few studies were identified on the role of OCs in smoking-related outcomes. Future work could explore the relationship between OC use and mood, stress, weight gain, and brain function/connectivity, as well as cessation outcomes. Understanding the role of OC use in these areas may lead to the development of novel smoking cessation interventions for premenopausal women.

IMPLICATIONS

This is the first review of the relationship between oral contraceptives (OCs) and smoking-related outcomes. The existing literature suggests that the use of OCs is related to increased nicotine metabolism and physiological stress response. However, the relationship between OC use and smoking-related symptoms (eg, craving) is mixed. Further, no published data were available on OC use and smoking cessation outcomes. Therefore, we recommend additional research be conducted to characterize the relationship between OC use and smoking cessation outcomes, perhaps as a function of the effect of OC use on mood, stress, weight gain, and brain function/connectivity.

Learning and memory performance following acute intranasal insulin administration in abstinent smokers

The highest incidence of relapse to smoking occurs within the first 2 weeks of a cessation attempt. In addition to enhanced nicotine craving, this phase of smoking cessation is also marked by learning and memory dysfunction. Many smokers are not able to overcome these symptoms, and they relapse to smoking shortly after trying to quit. In two clinical studies, we evaluated intranasal insulin for efficacy in improving learning and memory function during nicotine withdrawal. Our first study was a crossover evaluation (N = 19) following 20 hr of smoking abstinence. Study 2 was a parallel design study (N = 50) following 16 hr of abstinence. Intranasal insulin (60 IU) dose was administered in both studies and cognitive function was measured using California Verbal Learning Test-II. Intranasal insulin did not improve learning over the 5 verbal learning trials. In addition, intranasal insulin did not improve either short- or long-delay recall in either study. In summary, the one-time administration of intranasal insulin does not improve verbal learning and memory in smokers. Whether longer administration schedules may be of benefit should be evaluated in future studies.

Sex-dependent effects of nicotine on the developing brain

The use of tobacco products represents a major public health concern, especially among women. Epidemiological data have consistently demonstrated that women have less success quitting tobacco use and a higher risk for developing tobacco-related diseases. The deleterious effects of nicotine are not restricted to adulthood, as nicotinic acetylcholine receptors regulate critical aspects of neural development. However, the exact mechanisms underlying the particular sensitivity of women to develop tobacco dependence have not been well elucidated. In this mini-review, we show that gonadal hormone-mediated sexual differentiation of the brain may be an important determinant of sex differences in the effects of nicotine. We highlight direct interactions between sex steroid hormones and ligand-gated ion channels critical for brain maturation, and discuss the extended and profound sexual differentiation of the brain. We emphasize that nicotine exposure during the perinatal and adolescent periods interferes with normal sexual differentiation and can induce long-lasting, sex-dependent alterations in neuronal structure, cognitive and executive function, learning and memory, and reward processing. We stress important age and sex differences in nicotine's effects and emphasize the importance of including these factors in preclinical research that models tobacco dependence. © 2016 Wiley Periodicals, Inc.

Determinants of Smoking and Cessation Among Latinos: Challenges and Implications for Research

Tobacco is a significant burden to individual and public health, and disparities exist among Latino smokers with respect to use and cessation. Although the prevalence of smoking is lower for Latinos than for non-Latino Whites and the general U.S. population, numerous health disparities exist within the population of Latino smokers. Much is known about determinants of smoking and cessation but the vast majority of this knowledge is based on research with non-Latino White smokers. This results in at least two important challenges in tobacco research among Latino smokers: (i) demonstrating the generalizability of known determinants of smoking and cessation, and; (ii) identifying culturally relevant variables that influence smoking and cessation among Latinos. An argument for increased research in these areas is presented with a review of existing research among Latino smokers that demonstrates these needs. Research is summarized that suggests socioeconomic position, depressive symptomatology, physical dependence, and gender function differently as determinants of smoking and cessation among Latinos compared with the general population of smokers. Research is also reviewed that suggests the promise of acculturation, acculturative stress, and discrimination as culturally relevant determinants of smoking and cessation. Research and practice implications are discussed, and specific areas for future research are offered.

Comparative Effectiveness of Smoking Cessation Medications to Attenuate Weight Gain Following Cessation

OBJECTIVE

To compare the postcessation weight gain following the use of different FDA-approved smoking cessation medications among obese smokers.

METHODS

A retrospective cohort study was conducted using the General Electric (GE) electronic medical record database (2006-2011). The cohort consisted of obese adult smokers newly initiating use of an FDA-approved smoking cessation medication (i.e., bupropion vs. varenicline). The outcome variable was weight change at 3, 6, or 12 months following the first prescription. Descriptive analyses and t-tests were conducted to assess the frequency distribution of sample characteristics and their association with the postcessation weight change. Multivariate linear regression models were carried out to compare the weight change among the FDA-approved smoking cessation medications and to identify predictors of weight change at 3, 6, and 12 months after assessing the model assumptions.

RESULTS

The mean weight gain was 1.14 pounds (±17.26), 2.06 pounds (±18.46), and 3.06 pounds (±20.78) at 3-, 6-, and 12-month, respectively. Obese smokers who were prescribed varenicline had a mean weight gain of 1.18 pounds (±16.75), 2.14 pounds (±18.14), and 3.12 pounds (±20.89) for each follow up, while those who were prescribed bupropion had a mean weight gain of 0.23 pounds (±25.90), 0.22 pounds (±25.32), and 1.47 pounds (±17.50), respectively. Descriptive analysis showed that obese smokers taking bupropion had less weight gain than those taking varenicline at each follow up; however, this association was not statistically significant after accounting for all covariates.

CONCLUSIONS

While patients using bupropion gained slightly less weight compared to those using varenicline, type of smoking cessation medication was not a significant predictor of weight change in the multivariate linear regression model.

Assessment of affective and somatic signs of ethanol withdrawal in C57BL/6J mice using a short-term ethanol treatment

Alcohol is one of the most prevalent addictive substances in the world. Withdrawal symptoms result from abrupt cessation of alcohol consumption in habitual drinkers. The emergence of both affective and physical symptoms produces a state that promotes relapse. Mice provide a preclinical model that could be used to study alcohol dependence and withdrawal while controlling for both genetic and environmental variables. The use of a liquid ethanol diet offers a reliable method for the induction of alcohol dependence in mice, but this approach is impractical when conducting high-throughput pharmacological screens or when comparing multiple strains of genetically engineered mice. The goal of this study was to compare withdrawal-associated behaviors in mice chronically treated with a liquid ethanol diet vs. mice treated with a short-term ethanol treatment that consisted of daily ethanol injections containing the alcohol dehydrogenase inhibitor, 4-methylpyrazole. Twenty-four hours after ethanol treatment, mice were tested in the open field arena, the elevated plus maze, the marble burying test, or for changes in somatic signs during spontaneous ethanol withdrawal. Anxiety-like and compulsive-like behaviors, as well as physical signs, were all significantly elevated in mice undergoing withdrawal, regardless of the route of ethanol administration. Therefore, a short-term ethanol treatment can be utilized as a screening tool for testing genetic and pharmacological agents before investing in a more time-consuming ethanol treatment.

Existe-t-il des différences entre les hommes et les femmes en ce qui concerne les problèmes de toxicomanie ?

La consommation et la dépendance aux drogues furent longtemps considérées comme un problème typiquement masculin. Néanmoins, bien que l’abus et la dépendance à l’alcool, au cannabis et à la nicotine soient encore plus répandus chez les hommes, les différences de genre en ce qui concerne les stimulants et les opiacés ont largement disparu. Il semblerait également que les motivations pour commencer à consommer, l’escalade vers la dépendance et les taux de cessation diffèrent chez les hommes et les femmes. Les raisons qui expliquent ces différences sont multiples et complexes. Nous allons examiner ici les données des études épidémiologiques et cliniques concernant la consommation de diverses drogues chez des hommes et chez des femmes en contexte des facteurs socioculturels, psychologiques et neurobiologiques.

Does combination pharmacological intervention for smoking cessation prevent post-cessation weight gain? A systemic review

BACKGROUND

Most smokers who quit smoking gain weight. There are some interventions designed to limit weight gain following smoking cessation.

OBJECTIVE

To conduct a systematic review to evaluate if combination pharmacological therapy interventions for smoking cessation are effective in reducing post-cessation weight gain.

METHODS

The following databases were researched: Medline, PubMed, PsycINFO, CENTRAL and EMBASE. Detailed inclusion and exclusion criteria were specified a priori before conducting abstract and full text screening. Included studies were required to: (1) report data on combination pharmacotherapy including at least one FDA-approved smoking cessation medication; (2) report outcome measure of weight change from baseline to the end of follow up; (3) incorporate a minimum of 2-week follow-up; (4) recruit adult smokers. Studies were excluded if they had (1) behavioral interventions; (2) sample size of <30; (3) switching medications; or (4) they were not written in English. Abstracts and the full texts were reviewed independently by two investigators. Inclusion of studies was decided by a third independent investigator in case of disagreement between the two primary investigators.

RESULTS

Out of 1873 studies identified, 1083 studies were included for abstract screening. Finally, 12 studies met the eligibility criteria after full text screening of 242 studies. Seven studies showed that participants in the combined therapy group had less post-cessation weight gain than those in the group of individual drugs or placebo. Four studies did not report differential weight gain measures by treatment groups. Only one study showed that post-treatment weight gain in the combined therapy group was more than the monotherapy group, although the result was not statistically significant.

CONCLUSIONS

Seven out of twelve studies indicated that combination smoking cessation medications had less post-cessation weight gain than monotherapy or placebo in short term. Long term weight gain was not well documented by most of the studies and future research is warranted.

Tobacco addiction and the dysregulation of brain stress systems

Tobacco is a highly addictive drug and is one of the most widely abused drugs in the world. The first part of this review explores the role of stressors and stress-associated psychiatric disorders in the initiation of smoking, the maintenance of smoking, and relapse after a period of abstinence. The reviewed studies indicate that stressors facilitate the initiation of smoking, decrease the motivation to quit, and increase the risk for relapse. Furthermore, people with depression or an anxiety disorder are more likely to smoke than people without these disorders. The second part of this review describes animal studies that investigated the role of brain stress systems in nicotine addiction. These studies indicate that corticotropin-releasing factor, Neuropeptide Y, the hypocretins, and norepinephrine play a pivotal role in nicotine addiction. In conclusion, the reviewed studies indicate that smoking briefly decreases subjective stress levels but also leads to a further dysregulation of brain stress systems. Drugs that decrease the activity of brain stress systems may diminish nicotine withdrawal and improve smoking cessation rates.

Using treatment process data to predict maintained smoking abstinence

OBJECTIVES

To identify distinct subgroups of treatment responders and nonresponders to aid in the development of tailored smoking-cessation interventions for long-term maintenance using signal detection analysis (SDA).

METHODS

The secondary analyses (n = 301) are based on data obtained in our randomized clinical trial designed to assess the efficacy of extended cognitive behavior therapy for cigarette smoking cessation. Model 1 included only pretreatment factors, demographic characteristics, and treatment assignment. Model 2 included all Model 1 variables, as well as clinical data measured during treatment.

RESULTS

SDA was successfully able to identify smokers with varying probabilities of maintaining abstinence from end-of-treatment to 52-week follow-up; however, the inclusion of clinical data obtained over the course of treatment in Model 2 yielded very different partitioning parameters.

CONCLUSIONS

The findings from this study may enable researchers to target underlying factors that may interact to promote maintenance of long-term smoking behavior change.

Substance abuse in women

Gender differences in substance use disorders (SUDs) and treatment outcomes for women with SUDs have been a focus of research in the last 15 years. This article reviews gender differences in the epidemiology of SUDs, highlighting the convergence of male/female prevalence ratios of SUDs in the last 20 years. The telescoping course of SUDs, recent research on the role of neuroactive gonadal steroid hormones in craving and relapse, and sex differences in stress reactivity and relapse to substance abuse are described. The role of co-occurring mood and anxiety, eating, and posttraumatic stress disorders is considered in the epidemiology, natural history, and treatment of women with SUDs. Women's use of alcohol, stimulants, opioids, cannabis, and nicotine are examined in terms of recent epidemiology, biologic and psychosocial effects, and treatment. Although women may be less likely to enter substance abuse treatment than men over the course of the lifetime, once they enter treatment, gender itself is not a predictor of treatment retention, completion, or outcome. Research on gender-specific treatments for women with SUDs and behavioral couples treatment has yielded promising results for substance abuse treatment outcomes in women.

Acculturation differentially predicts smoking cessation among Latino men and women

OBJECTIVES

The current study examined the influence of gender, acculturation indicators, and their interaction on smoking cessation among Latinos.

METHODS

Logistic regression analysis was used to examine the main effects of gender, acculturation indicators, and their interactions on self-reported 7-day abstinence at 12-week follow-up among 271 Latino smokers seeking cessation counseling.

RESULTS

Analyses revealed significant main effects for several acculturation indicators and significant interactions of gender with number of years lived in the United States, proportion of life lived in the United States, and preferred media language (all P values <0.05). Follow-up analyses indicated no significant relationships between abstinence and acculturation indicators among women. Among men, abstinence rates increased with years in the United States, proportion of life in the United States, and preferred media language of English.

CONCLUSIONS

Greater acculturation predicted higher abstinence rates, but this relationship was restricted to men. This study is among the first to examine the effects of gender and acculturation on smoking abstinence among Latinos. Findings highlight the need for research focused on mechanisms underlying these relationships.

Sex differences in the self-administration of cannabinoids and other drugs of abuse

Many studies have provided evidence for important sex-dependent differences in the origins, outcomes and treatment of drug abuse and dependence. Preclinical studies typically have employed animal models of addiction, such as oral or intravenous self-administration, to untangle the environmental, neurobiological and genetic factors that contribute to the shift from occasional, recreational use to compulsive, uncontrolled intake of drugs. Craving and relapse of drug seeking in abstinent individuals have also been found to differ between men and women. Identification of the neurobiological basis of craving and drug dependence continues to pose a challenge to addiction research. Significant sex differences are emerging in substance-abuse-related behavior, which has increased the demand for research on how drug consumption may have different causes, progression and consequences in men and women. In keeping with epidemiological data in humans, differences between the two sexes in drug seeking and intake have been well-documented in animal studies, with most recent findings related to abuse of cannabinoids. Clinical and preclinical findings indicate that sex and gonadal hormones may account for individual differences in susceptibility to the reinforcing effects of addictive substances, and that differences in vulnerability to drug abuse may be mediated by the same biological mechanisms. This review focuses on the differences between males and females in relation to drug self-administration and how such behavior may be affected by hormonal status.

Smoking-related weight concerns among underserved, black maternal smokers

OBJECTIVE

To expand understanding of a smoking cessation barrier for women, weight concerns, in a medically underserved population.

METHODS

Baseline weight concerns were examined among 235 low-income, black maternal smokers enrolled in a smoking trial. Logistic regression evaluated factors related to weight concerns.

RESULTS

Higher BMI (OR 3.35, P < .001), intention to quit (OR 2.12, P = .02), more previous quit attempts (OR 1.14, P = .03), and less support for quitting (OR 0.81, P = .05) predicted weight concerns.

CONCLUSIONS

This is the first study to delineate factors predicting weight concerns in this population, thus expanding our understanding of a key cessation barrier and informing future cessation strategies in a population known to bear increased risk of tobacco-related disease.

Gender differences among smokers receiving interventions for tobacco dependence in a medical setting

OBJECTIVE

The purpose of this study was to assess differences between women and men receiving treatment for tobacco dependence through a clinical treatment program.

METHODS

We conducted a retrospective review of clinical data collected on 2139 ambulatory and 1259 hospitalized smokers receiving individualized tobacco dependence treatment from Jan 1, 2004 to Dec 31, 2005 through the Mayo Clinic Nicotine Dependence Center.

RESULTS

Overall, female smokers smoked less than males (p<0.001); were less likely to have received treatment for alcoholism (p<0.001); were more likely to have received treatment for past depression (p<0.001); were also less likely to have started smoking prior to 18 years of age (p=0.004 and p=0.008 for ambulatory and hospitalized patients, respectively); were less likely to be married (p<0.001); were less likely to be tobacco dependent (hospitalized smokers only p=0.04); and were more likely to have received a prescription for a smoking cessation medication (ambulatory smokers only, p=0.034). After adjustment for baseline characteristics, women and men did not differ in tobacco abstinence outcomes.

CONCLUSION

Although many gender differences are present among patients treated in a large ambulatory and hospital based tobacco treatment programs, gender is not associated with failure to achieve smoking abstinence.

Menstrual phase effects on smoking relapse

AIMS

To examine if menstrual phase affects relapse in women attempting to quit smoking.

DESIGN

An intent-to-treat randomized smoking cessation trial where women were assigned to quit smoking in either the follicular (F) or luteal (L) menstrual phase and were followed for up to 26 weeks. They were assessed for relapse by days to relapse and relapse phase to determine if those who begin a quit attempt during the F phase were more successful than those who begin during the L phase.

SETTING

Tobacco Use Research Center, University of Minnesota, Minneapolis, Minnesota.

PARTICIPANTS

A total of 202 women.

MEASUREMENTS

Latency to relapse from continuous and prolonged abstinence, point prevalence, phase of relapse, first slip within the first 3 and 5 days post-quit date, subject completion rates and symptomatology (i.e. withdrawal and craving).

FINDINGS

The mean days to relapse from continuous abstinence and relapse from prolonged abstinence for the F group were 13.9 and 20.6 days, respectively, and 21.5 and 39.2 days, respectively, for the L group. Using point prevalence analysis at 14 days, 84% of the F group had relapsed compared with 65% of the L group [chi(2)=10.024, P=0.002; odds ratio (OR) = 2.871, 95% confidence interval (CI), 1.474-5.590]. At 30 days, 86% of the F group relapsed, compared with 66% of the L group (chi(2)=11.076, P=0.001; OR=3.178, 95% CI, 1.594-6.334).

CONCLUSION

Women attempting to quit smoking in the F phase had less favorable outcomes than those attempting to quit in the L phase. This could relate to ovarian hormones, which may play a role in smoking cessation for women.

Effects of a body image challenge on smoking motivation among college females

OBJECTIVE

Previous correlational and quasi-experimental research has established that weight concerns and negative body image are associated with tobacco smoking, cessation, and relapse, particularly among young women. This study examined the causal influence of body image upon smoking motivation by merging methodologies from the addiction and body image literatures.

DESIGN

Using a cue-reactivity paradigm, the study tested whether an experimental manipulation designed to challenge women's body image-specifically, their weight dissatisfaction-influenced their motivation to smoke. Female college smokers (N= 62) were included in a 2 X 2 factorial, within-subjects design (body image cues X smoking cues).

MAIN OUTCOME MEASURES

Self-reported urge to smoke was the primary dependent measure, with skin conductance as a secondary measure.

RESULTS

As hypothesized, the presentation of smoking images and thin model images produced greater urges to smoke than control images. Additionally, trait weight concerns moderated the effect of the body image manipulation such that those women with greater weight concerns produced greater craving to the thin model image (when smoking cues were not present).

CONCLUSION

These findings provide initial evidence that situational challenges to body image are causally related to smoking motivation.

Efficacy of naltrexone in smoking cessation: a preliminary study and an examination of sex differences

This double-blinded, placebo-controlled trial evaluated the efficacy of naltrexone as an adjunct to standard smoking cessation treatment. Participants (N = 110) were adult male and female nicotine-dependent smokers who expressed interest in quitting smoking. All subjects received six sessions of behavioral counseling (1 hr/session for 6 weeks), and 1 month of the nicotine patch (21 mg for the first 2 weeks, 14 mg the third week, 7 mg the fourth week). Subjects were randomly assigned to the naltrexone or placebo group. The naltrexone group started at 25 mg daily for 3 days prior to the quit date, and increased to 50 mg/day on the quit date and following 8 weeks. At the end of medication treatment, the naltrexone group had better quit rates versus the placebo group (48% quit on naltrexone vs. 41% on placebo), but this difference was not statistically significant. However, men and women differed on several measures: in the placebo group, women had significantly lower quit rates than men (39% vs. 67%, p<.05), but in the naltrexone group, women had quit rates comparable with those of men (58% vs. 62%, p = ns). Further examination revealed that naltrexone significantly reduced men's and women's cessation-related weight gain and selectively reduced women's urge to smoke to relieve negative affect and withdrawal. The results suggest continued examination of naltrexone as an adjunct in smoking cessation, particularly in female smokers, who have historically shown worse outcomes with traditional treatment methods.

Gender and weight concerns in adolescent smokers

The aim of this study was to examine smoking-specific weight concerns in a well-characterized sample of adolescent daily smokers and the influence of gender, age, and body mass index (BMI). Adolescent smokers (n=103) were asked two smoking-specific weight concern questions: "How much do cigarettes help you control your weight?" and "How concerned are you about gaining weight as a result of quitting?" A significant positive relationship was found between average daily cigarette use and belief in smoking as a means to control weight and a significant negative relationship between the years of smoking and belief that smoking controls weight. There was no significant relationship between BMI and smoking to control weight for females, whereas for males, there was a positive relationship, indicating that heavier males were more likely to report smoking to control weight. Additionally, females who smoked more cigarettes reported more concern about gaining weight upon quitting, a pattern not seen in males. Results highlight potentially important gender differences in the relationship between weight concerns and smoking and the influence these concerns may have on quitting smoking.

Treating tobacco use and dependence in clinical practice

Physicians are in a unique position to advise smokers to quit by the ability to integrate the various aspects of nicotine dependence. This review provides an overview of the intervention strategies for smokers presented in a primary care setting. The strategies that are used for smoking cessation counselling differ according to the patient's readiness to quit. For smokers who do not intend to give up smoking, physicians should inform about tobacco use and the benefits of cessation. For smokers who are dissonant, physicians should use motivational strategies, such as discussing the barriers to successful cessation and their solutions. For smokers who are ready to quit, the physician should show strong support, help set a date to quit, prescribe pharmaceutical therapies for nicotine dependence, such as nicotine replacement therapy (i.e., gum, transdermal patch, nasal spray, mouth inhaler, lozenges, and micro and sublingual tablets) and/or bupropion (an atypical antidepressant thought to work by blocking the neural re-uptake of dopamine and/or noradrenaline), with instructions for use, and suggest behavioural strategies to prevent relapse. The efficacy of all of these pharmacotherapies is comparable, roughly doubling the cessation rates over control conditions.

The diagnosis of a smoking-related disease is a prominent trigger for smoking cessation in a retrospective cohort study

OBJECTIVE

We evaluated the impact of demographic factors, smoking patterns, and the occurrence of smoking-related diseases on smoking cessation, with a particular emphasis on the temporal relationship between diagnosis of smoking-related diseases and cessation.

STUDY DESIGN AND SETTING

A cohort was assembled of participants of a general health screening examination aged 50-74 years. Lifetime smoking habits and medical history were obtained by a self-administered questionnaire. In a retrospective cohort study approach, predictors of cessation among ever-smokers (n = 4,575) were identified using the extended proportional hazards model.

RESULTS

Male gender, late onset of smoking, and higher educational level were predictive of cessation. However, the by far strongest predictors of cessation were diagnoses of smoking-related diseases: relative cessation rates in the year of disease occurrence were 11.2 for myocardial infarction (95% confidence interval CI = 8.9-14.0), 7.2 for stroke (95% CI = 5.1-11.6), 2.5 for diabetes mellitus (95% CI = 1.6-4.0) and 4.8 for cancer (95% CI = 3.1-7.4) relative to years before diagnosis of the respective diseases.

CONCLUSION

Our results underline the key role of perceived detrimental effects of smoking for cessation. When smokers personally experience the health consequences of smoking, many permanently quit.

Nicotine patch and lozenge are effective for women

It has been hypothesized that women may be less likely to obtain therapeutic benefit from nicotine replacement therapy (NRT). The present study tested this hypothesis, using two different types of NRT medications. A secondary analysis of two randomized clinical trials was performed: One compared active 21-mg nicotine patch with placebo among 193 men and 309 women, and the other compared active 2-mg or 4-mg nicotine lozenge with placebo among 788 men and 1,030 women. Using logistic regression analysis of 6-month continuous abstinence and survival analysis, we assessed the efficacy of patch and lozenge among women and tested for a gender x treatment interaction. Active NRT was more effective than placebo among women, for both patch and lozenge. In the lozenge trial, women were less successful than men. The gender x treatment interaction was not significant in either study, whether assessed by logistic regression or survival analysis. In the lozenge trial, gender moderated the effects of smoking rate and dependence (but not treatment) on outcome: These variables affected success rates only among women. Treatment with nicotine patch or lozenge is effective for women, and the analysis did not reveal significant gender differences in efficacy. Gender differences in outcome may be moderated by nicotine dependence.

Perceived risks and benefits of smoking cessation: gender-specific predictors of motivation and treatment outcome

The primary aim of this study was to examine gender differences in perceived risks and benefits of smoking cessation and their relationship to pretreatment motivation and treatment outcome. No validated measures that comprehensively assess perceived risks and benefits associated with smoking cessation were available in the literature; consequently, we developed a self-report instrument [Perceived Risks and Benefits Questionnaire (PRBQ)] for this purpose. A sample of 573 treatment-seeking smokers (48% female) entering smoking cessation trials completed the PRBQ, and its association with treatment outcome was assessed in a subsample of 93 participants. Overall, the PRBQ demonstrated good psychometric properties. Females indicated greater likelihood ratings of perceived risks and benefits than males. For women and men, perceived benefits were positively associated with motivation, and perceived risks were negatively associated with motivation and treatment outcome. Women evidenced stronger associations between perceived risks and pretreatment motivation, and treatment outcome. Knowledge of perceived risks and benefits associated with smoking cessation is critical for public education campaigns and could inform intervention strategies designed to modify sex-specific beliefs associated with lowered behavioral intentions to quit smoking.

Cost-effectiveness analysis of a complementary health intervention: the case of smoking relapse prevention

OBJECTIVES

We assess the cost-effectiveness of smoking relapse prevention interventions designed to keep quitters from resuming the use of cigarettes. Because relapse prevention is complementary to smoking cessation efforts, the appropriate test of its cost-effectiveness is whether it reduces the incremental cost-effectiveness ratio (ICER) of smoking cessation. The major goal of the study is to carry out such a test.

METHODS

Data from a randomized trial that ascertained the effectiveness of alternative modes of smoking relapse prevention are combined with ICER estimates of smoking cessation to assess whether relapse prevention is cost-effective.

RESULTS

The trial produced convincing evidence that relapse prevention yields statistically significant reductions in the proportion of quitters who are smoking at 24 months postquit. The intervention effects are substantial enough to raise the denominator terms of the smoking cessation ICER and, thereby, offset the amount relapse prevention adds to cost numerator terms. In this sense, smoking relapse prevention tends to pay for itself.

CONCLUSIONS

Smoking relapse prevention is a highly cost-effective addition to current efforts to curb cigarette consumption. Complementary health interventions of this sort should be assessed by different methods than those commonly found in the cost-effectiveness literature.

Energy intake and physical activity during short-term smoking cessation in postmenopausal women

This study assessed the effect of short-term (2-week) smoking abstinence on weight gain, energy intake, and physical activity in 60 postmenopausal women. Participants were stratified by their use of hormone replacement therapy (HRT; currently taking/not taking) and then randomized to abstinence or continued smoking for 2 weeks. The 30 abstainers gained a mean of 1.28 kg, compared with a 0.54 kg loss for the 30 continued smokers (P=.002). The abstainers also reported a significantly greater increase than did the smokers in total kilocalorie and in carbohydrate consumption for both weeks. There were no changes in physical activity and HRT effect. These are the first published findings on caloric intake and weight gain during smoking abstinence in postmenopausal women-an understudied population in the smoking cessation literature.

Heterogeneity in 12-month outcome among female and male smokers

AIMS

To examine heterogeneity in outcome following treatment for smoking cessation with combined bupropion SR and behavioral counseling in women and men.

DESIGN, SETTING, PARTICIPANTS

This study included 875 women and 649 men recruited from a large health-care system and randomized to one of four combinations of treatment [two dosage levels of bupropion SR (Zyban, 150 mg and 300 mg) were crossed with two counseling programs of lower and higher intensity to create a four-cell design].

MEASUREMENTS AND FINDINGS

A comprehensive set of relevant individual characteristics prior to treatment and treatment characteristics was included in the analysis. Smoking outcome at 12 months was defined as point-prevalence of any regular smoking within the 7 days prior to follow-up contact. Classification and regression tree analysis identified six subgroups in women that ranged in proportion of non-smokers from 9.8% to 42.9% and six subgroups in men that ranged in proportion of non-smokers from 17.3% to 50.0%.

CONCLUSIONS

These results indicate the presence of a substantial amount of variation in treatment outcome among women and men receiving combined bupropion SR and counseling. Variation in outcome could be reduced by providing treatments tailored to subgroups of individuals who are at exceptionally high risk for smoking following cessation.

Rationale, design, and baseline data for Commit to Quit II: an evaluation of the efficacy of moderate-intensity physical activity as an aid to smoking cessation in women

BACKGROUND

Commit to Quit II is a 4-year randomized controlled trial comparing the efficacy of a cognitive-behavioral smoking cessation treatment plus moderate-intensity physical activity with the same cessation treatment plus contact control.

METHODS

Sedentary women smokers (n = 217) were randomized to receive 8 weeks of treatment followed by 12 months of follow-up. This article outlines the study design, presents baseline data about the sample, and compares the sample to national samples and to our previous study examining vigorous-intensity exercise as an aid to smoking cessation.

RESULTS

Married and white participants reported significantly higher levels of nicotine dependence than unmarried and minority participants. Higher levels of nicotine dependence were also significantly related to lower smoking cessation self-efficacy and higher levels of self-reported depression, anxiety, and perceived stress. Additionally, participants smoked significantly more cigarettes (mean 20.6) than a national sample of female smokers (mean 16.1). On average, participants were significantly older, weighed significantly more, and scored significantly higher on a measure of anxiety than participants in our previous trial.

CONCLUSIONS

Our sample consisted of women who were heavier smokers than national samples seeking treatment. It remains to be determined how this will impact their ability to attain cessation in the present study.

The emotional experience of intercourse and sexually transmitted diseases: a decision-tree analysis

BACKGROUND

Epidemiologic data document high risks for many sexually transmitted diseases (STDs) among US adolescents and young adults.

GOAL

This case-control study used decision trees to investigate the relationship between STD incidence and emotional reactions to intercourse.

STUDY DESIGN

For this study, 188 adolescents and young adults (mean age, 24.9 years [SD = 8.2]) at a regional public STD clinic completed a behavioral and psychological questionnaire and underwent a workup for STD.

RESULTS

The prevalence of STD in this group was 44.8%. Decision-tree analysis identified emotional reactions to intercourse that were associated with STD diagnosis for some patients: feeling good about oneself after sex half the time or less (OR = 3.21; 95% CI = 1.73-5.95), feeling comfortable during sex half the time or less (OR = 2.17; 95% CI = 1.07-4.40), and feeling angry after sex (OR = 1.90; 95% CI = 0.91-3.99). Findings of a logistic regression model of emotional reactions to intercourse were significant (chi-square = 24.6; df = 8; P < 0.002), but adding behavioral variables did not improve prediction.

CONCLUSIONS

For some of these young adults at the time of life when they are at highest risk of STD, emotional factors have higher odds ratios for STD diagnosis than the traditionally assessed behavioral variables. This underscores the need for interventions targeted to specific subgroups and for readily available mental health services.

Smoking cessation in women. Special considerations

Women may be at relatively greater risk of smoking-related diseases than men but tend to have less success than men in quitting smoking. The failure of most outcome studies to report results by gender and the lack of statistical power for detecting significant gender differences currently do not allow for many firm conclusions to be drawn about smoking cessation rates in women, but several trends warrant attention and further study. First, the difference in cessation rates for women versus men may be even greater in trials of nicotine replacement therapies (NRT). This suggests that women benefit less from NRT relative to men, although this difference may depend on the particular form of NRT (e.g. inhaler versus gum). On the other hand, some non-NRT medications may reverse the poorer outcome of women, producing quit rates in women comparable with those in men. Gender differences in outcome, as well as overall success rates, with NRT and some of the non-NRT medications appear to be enhanced when treatment includes substantial behavioural counselling. However, while several of the non-NRT medications may be particularly appropriate to consider for treating women trying to quit smoking, adverse effects may limit widespread use of some of these drugs, such as clonidine and naltrexone. Thus, even if the gender differences in outcome with NRT versus non-NRT drugs are confirmed in further research, such findings do not necessarily justify limiting NRT use in women, because such treatment is clearly effective and is likely to be safer and more readily available than non-NRT medications. Nevertheless, study of the mechanisms by which some non-NRT drugs are effective in women may aid our understanding of factors that are more influential in smoking behaviour in women than in men. Secondly, smoking cessation treatment for women must address several other issues that often emerge, and these are most likely to require behavioural counselling that is tailored to these problems. These issues include concern about bodyweight gain, restrictions on medication use in pregnant smokers, variability in mood and withdrawal as a function of menstrual cycle phase, harnessing social support to foster abstinence, and the possibility that smoking-associated environmental cues may be more influential in smoking behaviour in women than men. Greater attention to gender differences in clinical trial outcomes and to addressing concerns of women smokers may aid in the development of substantially improved smoking cessation interventions for women.

Recruiting women into a smoking cessation program: who might quit?

This article describes women who called a research line to quit smoking and identifies correlates of confidence in quitting among the callers. Approximately 4,000 women called the study line to participate after a single press release, indicating intensive interest in quitting. Overall, the randomized sample of women was aged 26 to 65 years, reported smoking just over one pack per day, was mostly White, predominantly employed, and had quit an average of two times the past year before joining the study. Standard background variables, such as age, income, body weight and smoking history variables did not predict baseline self-efficacy or confidence in quitting. However, level of stress, cognitive restraint, and weight gain concerns did predict self-efficacy. These data indicate strong interest in quitting among women and highlight the role of affect and weight concerns in quitting confidence.

Bupropion for Smoking Cessation

OBJECTIVES

To identify predictors of smoking abstinence at the end of medication use that could assist in the optimal use of a sustained-release (SR) form of bupropion for treating cigarette smokers.

DESIGN

A double-blind, placebo-controlled, dose-response trial.

SETTING

Multicenter (three sites) study conducted in the United States.

PARTICIPANTS

Six hundred fifteen healthy men and women (> or = 18 years of age) who were smoking > or = 15 cigarettes per day and who were motivated to stop smoking.

INTERVENTION

Random assignment of patients to placebo or SR bupropion treatment, 100, 150, or 300 mg/d, for 7 weeks (total duration of study was 52 weeks: 7 weeks of treatment and 45 weeks of follow-up).

MEASUREMENTS AND RESULTS

Logistic regression was used to identify predictors of abstinence at the end of the medication phase. Univariate predictors included the following: bupropion dose (p < 0.001); older age (p = 0.024); lower number of cigarettes smoked per day (cpd) (p < 0.001); lower Fagerström Tolerance Questionnaire score (p = 0.011); longest time previously abstinent that was < 24 h or > 4 weeks (p < 0.001); absence of other smokers in the household (p = 0.021); greater number of previous stop attempts (p = 0.019); and study site (p = 0.004). Multivariate predictors of abstinence at the end of the medication phase were the following: higher bupropion dose (p < 0.001); lower number of cpd (p < 0.001); longest time previously abstinent from smoking (p = 0.002); male gender (p = 0.014); and study site (p = 0.021).

CONCLUSION

Bupropion SR therapy was effective in treating cigarette smokers independently of all other characteristics studied. Lower smoking rate, brief periods (ie, < 24 h) or long periods (ie, > 4 weeks) of abstinence with previous attempts to stop smoking, and male gender were predictive of better outcomes, independent of the dose of bupropion that was used.

Cigarette smoking and women's respiratory health

Cigarette smoking is claiming an increasing health toll among women, with rising morbidity and mortality related to lung cancer and COPD. Whether women are more susceptible to the effects of cigarettes with regard to carcinogenesis and development of COPD remains controversial. Gender differences clearly exist in certain aspects of cigarette-related disease, including histologic distribution of lung cancer and the ability of smokers to quit. It is likely that gender differences also exist in the reasons that individuals choose to smoke. Understanding those reasons will be important in developing targeted programs for smoking cessation and in addressing the challenge of the prevention of smoking initiation in women.

Sex differences in nicotine effects and self-administration: review of human and animal evidence

Although both the human and animal literatures are notable for the general lack of attention paid to possible sex differences in drug self-administration behavior, evidence is accumulating to suggest that males and females may differ in factors that maintain tobacco smoking or nicotine self-administration. Self-administration of nicotine per se may be less robust in women, and women are less sensitive than men to some effects of nicotine that may be reinforcing. Compared to men, smoking behavior of women may be influenced more by non-nicotine stimuli associated with smoking, suggesting greater conditioned reinforcement of smoking in women. Moreover, nicotine replacement, the current standard treatment for smoking cessation, is sometimes less effective in women, further suggesting the need for greater consideration of non-nicotine factors that may maintain women's smoking. Very recent research on rats also indicates sex differences in nicotine self-administration. However, these differences are complex and suggest that nicotine-seeking behavior is composed of several components, including hedonic, incentive-motivational, and conditioning effects; males and females may differ in one or more of these components. Menstrual or estrous cycle phase effects on the maintenance of nicotine self-administration are not particularly apparent in humans or animals, although cycle phase may influence other stages of dependence (e.g., withdrawal symptoms during cessation). Future research should evaluate further the consistency of results across human and non-human species, identify the conditions and procedures under which sex differences are observed, and elucidate the specific components of reinforcement that may differ between males and females. Studies also should examine the possible generalizability of these sex differences to other drugs of abuse. Identification of specific factors responsible for these sex differences may lead to improved interventions for smoking cessation and other substance abuse in women.

Gender differences in the pharmacology of nicotine addiction

Smoking rates have declined in recent years less rapidly in women than in men. More adolescent girls than boys are currently smoking. Quitting smoking is reported in many studies to be more difficult in women than in men. These observations suggest that there may be gender differences in the nature of nicotine addiction. Gender differences in various pharmacological processes involved in nicotine addiction are reviewed. Women take in less nicotine from smoking per cigarette than men but, because of slower metabolism, nicotine levels in the body for a given number of cigarettes per day are similar in male and female smokers. Women tend to be less sensitive to the discriminative effects of nicotine and tend to regulate nicotine intake less precisely than men. On the other hand, women appear to be more sensitive to the effects of nicotine in reducing negative affect and reducing body weight. There is a strong association between depression and smoking, and this association appears to be stronger in women than in men. Women tend to respond more to environmental cues associated with smoking than do men. Thus, several lines of evidence suggest that nicotine addiction is different in women than in men. Understanding the basis for gender differences may be of utility in individualizing and optimizing smoking cessation therapy.

Smoking cessation. 2: Components of effective intervention

Smoking cessation treatment is an essential component of comprehensive healthcare, but many healthcare providers lack formal training and are hesitant to provide such intervention. The recently published US Agency for Health Care Policy and Research (AHCPR) Smoking Cessation Clinical Practice Guideline provided empirically based recommendations to address these issues. The most effective components of smoking cessation include the use of nicotine replacement therapy, provider support and encouragement, and training in such skills as problem solving and coping. Methods of using these recommendations are illustrated, and sample scripts are offered to serve as references for providers from various disciplines who conduct smoking cessation interventions.

Abstinence effects as predictors of 28-day relapse in smokers

The present analysis sought to determine the relationship between abstinence effects in 64 ex-smokers (mean age = 41.1 years) and the rate at which they relapsed over 4 weeks of biochemically confirmed follow-up. This analysis focused on six abstinence effects that play a central role in the DSM-III-R and DSM IV definitions of withdrawal from nicotine: anger, depression, craving, appetite, confusion, and tension. Significant increases were observed for all six symptoms following cessation, and, with the exception of craving, substantial intercorrelations among the abstinence effects were noted. Cox proportional hazards survival models identified increases in anger, depressed mood, and craving to be significantly associated with a shorter time to relapse (all p < .03). Stepwise Cox proportional hazards survival analysis identified increases in depressed mood and craving as the most significant combination of abstinence effects in relation to time to relapse. A more stringent test of the potency of the relationship between these abstinence effects and time to relapse was conducted in which two other risk factors in this sample, method of quitting and education level, were also included in the model testing sequence. Even after adjustment for these significant risk factors, the increase in craving remained a significant predictor of a higher rate of relapse. This result suggests a robustness to this particular abstinence effect as a determinant of the speed with which ex-smokers relapse over a 1-month interval after cessation.

The relationship of Type A behavior and its components to all-cause mortality in an elderly subgroup of men from the Western Collaborative Group Study

This study examined prospectively the relationship of Type A behavior and its components to all-cause mortality in 1,118 men (age 60 to 86) who participated in a 27-year follow-up examination of the Western Collaborative Group Study. Global Type A/B behavior was assessed in these subjects using a modified version of the Structured Interview. Additional psychological data that related to this construct were obtained from self-report questionnaires. The relationship of these data, controlling for other biological risk factors, to 6-year all-cause mortality was investigated by means of a tree-structured survival analysis (TSSA). Using age, Type A behavior, Cook-Medley hostility, ever smoking, and cancer status at follow-up, TSSA identified 6 subgroups that differed in survival rates and associated risk factor profiles. The most favorable survival was experienced by 2 subgroups, one composed of older Type A subjects who scored the lowest on anger-hostility and depression, the other consisting entirely of Type B subjects who had never smoked. The worst survival was experienced by subjects with diagnosed cancer at the 27-year follow-up, and intermediate survival rates were experienced by 3 subgroups that differed markedly on age, smoking, Type A/B behavior, and Cook-Medley hostility. The present study is the first to characterize Type A's with favorable and unfavorable survival rates among the elderly.

Willingness of female smokers to tolerate postcessation weight gain

When asked how much weight they would be willing to gain if they quit smoking, women smokers replied 5.0 +/- 5.8 pounds (2.3 +/- 2.6 kg), compared with 10.7 +/- 7.6 pounds (4.9 +/- 3.5 kg) for men. Seventy-five percent of women, vs. 35% of men, were unwilling to gain more than 5 pounds (2.3 kg). White women were willing to gain 4.2 +/- 4.5 pounds (1.9 +/- 2.0 kg) compared with 11.1 +/- 10.7 pounds (5.0 +/- 4.9 kg) for Black women. In women under 25 years of age, 57% were unwilling to gain any weight at all, but even among women older than 40, 39% were unwilling to gain weight. Willingness to gain was negatively correlated with Body Mass Index, but even among nonoverweight women, 33% were unwilling to gain weight. Similarly, willingness to gain was negatively correlated with restrained eating, but even among low-restraint women, 22% were unwilling to gain weight. These findings suggest that unwillingness to gain is endemic among female smokers, that success in persuading them to accept a gain of more than 5 pounds (2.3 kg) as a final outcome is unlikely, and that strategies for postponing gain until cessation is well established, combined with waiting until weight stabilizes before determining what weight-management measures are needed, may be more effective.

Individual variability in responses to nicotine

Individual variability in acute responses to nicotine, which may be defined as variable magnitude of effects following controlled dosing, is generally attributed to stable characteristics of tobacco users such as genetic/constitutional factors or to chronic behavioral factors (e.g., long-term use of other drugs). Often overlooked, however, is that such variability may also be due to the transient influence of the situational factors in which people consume nicotine, such as acute stress or physical activity. Results of selected studies from the author's laboratory provide examples of each of these sources of variability in nicotine responding on subjective, behavioral, and physiological measures. All studies used a nasal spray method of nicotine dosing or controlled smoking (paced puffing) to control acute nicotine exposure, an essential methodological feature of any research on individual differences in acute responses to nicotine. As an example of genetic/constitutional factors, gender differences in nicotine responding have begun to receive some attention, with few differences emerging. However, females may be more responsive than males to nonnicotine stimuli associated with smoking (e.g., sight and taste of smoke). In terms of chronic behavioral factors, long-term use of nicotine produces attenuation of most subjective and some behavioral effects of nicotine, reflecting chronic tolerance, and the possibility that chronic use of other drugs may alter responses to nicotine (i.e., cross-tolerance or cross-sensitization) deserves greater study. Of particular emphasis in this review is the modulating influence of acute situational factors on nicotine responding. Human studies have shown that magnitude of nicotine's subjective effects may depend on the predrug subjective state, level of physical activity vs. rest, and concurrent acute intake of other drugs, among other situational factors. Proper consideration of these situational factors may reveal the greatest source of individual variability in responding to nicotine and clarify the impact of more stable genetic/constitutional or chronic environmental factors.

Effect of smoking cessation and relapse on cardiovascular levels and reactivity

This study was designed to investigate the effect of smoking cessation on heart rate, blood pressure, and finger temperature absolute levels and reactivity to a range of laboratory challenges. The 148 quitters (mean age = 43.3 years, mean amount smoked = 24.9 cigarettes per day, mean years smoked = 25.2) completed three assessments: an average of 4 +/- 2.8 days before cessation (Exam 1), an average of 2 +/- 1.0 days after cessation (Exam 2), and an average of 20 +/- 5.5 days after cessation (Exam 3). A nonsmoking group (n = 39) was similarly assessed three times to control for effects related to repeated testing. Comparison of group changes from Exam 1 to Exam 2 indicated that smoking cessation produced a significant decrease in heart rate during rest and during all stressors (mean = -8.9 bpm). Those quitters who remained abstinent or smoked occasionally showed minimal changes in heart rate from Exam 2 to Exam 3, but those quitters who returned to their previous smoking level showed a significant increase in heart rate from Exam 2 to Exam 3. None of the indices of cardiovascular reactivity changed across exams, and neither did absolute levels of blood pressure or finger temperature at rest or during stressors. The possible mechanisms producing a selective heart rate decline after smoking cessation in the absence of pressor or vasodilation effects are discussed.