Associations between self-control and dimensions of nicotine dependence: A preliminary report

Self-control plays an important role in several health-related behaviors, including cigarette smoking. There is some evidence that individual differences in self-control are negatively associated with overall levels of nicotine dependence but, to our knowledge, finer-grained relationships between these constructs have not been explored. This is an important knowledge gap, as nicotine dependence is thought to be composed of separate dimensions that motivate smoking behavior in relatively unique ways. The goal of this preliminary study was to begin to characterize the potentially nuanced associations between self-control and facets of nicotine dependence using data pooled from two previous studies (n = 282). Specifically, we examined the correlation between self-control and the following dimensions of nicotine dependence: compulsion to smoke due to craving and desire to avoid withdrawal symptoms; preference for smoking over other reinforcers; reduced sensitivity to the effects of smoking; consistency of smoking patterns; and smoking behavior that is rigid and immutable. In line with prior research, self-control was negatively correlated with overall levels of dependence. As predicted, however, self-control was differentially associated with distinct dimensions of nicotine dependence. Specifically, self-control was negatively correlated with the compulsion to smoke due to craving and desire to avoid withdrawal symptoms but positively correlated with the consistency of smoking patterns. Given the potential conceptual and clinical importance of such effects, additional research investigating the role(s) that individual differences in self-control play in addiction to cigarettes would be useful.     

Trait anxiety and nicotine dependence in adolescents: a report from the DANDY study

The Revised Children's Manifest Anxiety Scale (RCMAS) and the Hooked on Nicotine Checklist (HONC) were used to measure trait anxiety and tobacco dependence in a population of 581 adolescents. Smokers demonstrated higher mean RCMAS scores (9.3, S.D.=6.5) than nonsmokers did (7.4, S.D.=6.2, t=-3.7, P<.001). Participants with symptoms of tobacco dependence had higher RCMAS scores (mean=11.6, S.D.=6.0, n=115) than did the participants without symptoms (mean=7.8, S.D.=6.0, n=177, t=-5.3, P<.001). Scores on the RCMAS and the HONC correlated positively (n=292, r=.32, P<.001). Participants who had felt relaxed in response to their first exposure to nicotine were also more likely to develop dependence and to report that stress caused cravings or a need to smoke. Trait anxiety and relaxation in response to the first dose of nicotine were unrelated and appear to be independent risk factors for the development of nicotine dependence and a reliance on tobacco to cope with stress.     

Pharmacotherapy of nicotine dependence

Withdrawal treatment of cigarette smokers is a task of the utmost urgency in view of the consequences for national health programs and legislative policies of the high morbidity and mortality rates caused by smoking. Smokers need medical consultation in addition to drug-based treatment, but this results in self-willed quitting of the smoking habit in a limited number of smokers only. From the point of view of the criteria of "evidence-based medicine", non-drug methods such as hypnosis therapy and acupuncture are not effective (odds ratio = 1.22). Among the drug-based methods, treatment with nicotine substitution preparations has shown confirmed efficacy in numerous studies (odds ratio 1.63 to 2.67, depending on the application form used) and results in successful withdrawal from the smoking habit in 30-40% of cases. A decisive problem in the initial therapeutic phase appears to be the amount of the applied nicotine dose, but beyond that can be mastered above all by combining 2 or 3 application forms (patchs, chewing gum, nasal spray). Treatment is then continued for 4-12 weeks, depending on the degree of dependence, with successively reduced nicotine dosage. Two controlled studies with disparate designs have been done on bupropion (odds ratio 2.3/3.0). However, further studies are desirable due to concern about undesirable effects of bupropion described recently. Other substances subjected to trials in years past, such as clonidine, lobeline, mecamylamine and antidepressants including buspirone cannot be recommended on the basis of current data for treatment of smokers seeking a withdrawal cure.     

Evaluating fatigue in lupus-prone mice: preliminary assessments

Fatigue is a debilitating condition suffered by many as the result of chronic disease, yet relatively little is known about its biological basis or how to effectively manage its effects. This study sought to evaluate chronic fatigue by using lupus-prone mice and testing them at three different time periods. Lupus-prone mice were chosen because fatigue affects over half of patients with Systemic Lupus Erythematosus. Eleven MLR⁺/₊ (genetic controls) and twelve MLR/MpJ-Fas<lpr>/J (MRL/lpr; lupus-prone) mice were tested three times: once at 12, 16 and 20 weeks of age. All mice were subjected to a variety of behavioral tests including: forced swim, post-swim grooming, running wheel, and sucrose consumption; five of the MLR⁺/₊ and five of the MLR/lpr mice were also tested on a fixed ratio-25 operant conditioning task. MRL/lpr mice showed more peripheral symptoms of lupus than controls, particularly lymphadenopathy and proteinuria. Lupus mice spent more time floating during the forced swim test and traveled less distance in the running wheel at each testing period. There were no differences between groups in post-swim grooming or in number of reinforcers earned in the operant conditioning task indicating the behavioral changes were not likely due simply to muscle weakness or motivation. Correlations between performance in the running wheel, forced swim test and sucrose consumption were conducted and distance traveled in the running wheel was consistently negatively correlated with time spent floating. Based on these data, we conclude that the lupus-prone mice were experiencing chronic fatigue and that running wheel activity and floating during a forced swim test can be used to evaluate fatigue, although these data cannot rule out the possibility that both fatigue and a depressive-like state were mediating these effects.     

Intravenous nicotine reduces cerebral glucose metabolism: a preliminary study.

Nicotine is self-administered by smoking tobacco products, and enhances positive mood (at least in smokers). Since most drugs of abuse decrease regional cerebral metabolic rate(s) for glucose (rCMRglc) in human subjects, we posited that administration of nicotine would similarly reduce rCMRglc. Positron emission tomography (PET) with [F-18]fluorodeoxyglucose was used to assess the effects of intravenous nicotine (1.5 mg) on cerebral glucose metabolism in six healthy male volunteers (21-38 years of age). Two PET assays (placebo and nicotine) were performed, and subjective self-reports of mood and feeling state were collected. Data were analyzed using analysis of variance. Nicotine reduced global glucose metabolism (by 9.51% of placebo control), with reductions in most of the 30 individual regions tested. Nine regions had bilateral effects that reached statistical significance (p&<0.05, uncorrected for the number of regions tested), although the statistical model used did not separate these effects from a global effect. The subjects reported both positive and negative effects of nicotine on mood/feeling state. The widespread decreases in cerebral metabolism are consistent with the many effects of nicotine on cognition and mood. The findings indicate that nicotine resembles other drugs of abuse in reducing brain metabolism, perhaps by a common mechanism.     

Quantitative medial temporal lobe brain morphology and hypothalamic-pituitary-adrenal axis function in cocaine dependence: a preliminary report

Preclinical and clinical studies have shown that cocaine increases plasma adrenocorticotropin hormone (ACTH) and cortisol. Chronic elevation of plasma cortisol exerts direct toxic effects upon hippocampal neurons and exacerbates hippocampal damage resulting from ischemia and seizures. The authors tested for evidence of hippocampal damage in patients with chronic cocaine dependence. Medial temporal lobe and total brain volumes were quantified using magnetic resonance imaging (MRI) in 27 patients with cocaine dependence and 16 healthy subjects. Basal and ovine corticotropin releasing hormone (oCRH) stimulated ACTH and cortisol levels were also examined in a subset of 8 healthy and 9 cocaine dependent subjects after 21 days of abstinence. No evidence for decreased hippocampal or total brain volume in cocaine dependence was observed. Similarly, basal and oCRH stimulated ACTH and cortisol levels in cocaine dependent patients did not differ from those in healthy subjects.     

Finding order in the DSM-IV nicotine dependence syndrome: a Rasch analysis

Little is known about the relative severity or typical sequence of Diagnostic and Statistical Manual (DSM-IV) symptoms of nicotine dependence. Using data from the National Comorbidity Study (NCS), the current study used a Rasch logistic item response model to assess the unidimensionality of the construct of nicotine dependence, to identify which symptoms are associated with high levels of dependence, and to determine whether the dependence symptoms and typical symptom patterns are influenced by age, gender, race and income level. The nicotine dependence symptoms provided reasonable coverage of the dependence syndrome and can be used to scale individuals reliably. However, attention to potential demographic differences in responding to particular symptoms is needed. Furthermore, additional symptoms that describe behavioral changes that support continued smoking would be useful in helping to map the lower and higher ranges of dependence continuum. Evaluation of the typical pattern of responses to the nicotine dependence symptoms suggested that most smokers responded in a predictable manner. However, the tendency for younger smokers to provide more atypical responses than other smokers suggests a need to develop more specialized items for this population. More precise assessment of nicotine dependence would improve the predictive value of these measures and ultimately help inform nicotine dependence treatments.     

Compulsive smoking: the development of a Rasch homogeneous scale of nicotine dependence

The unidimensionality of nicotine dependence has not been established firmly yet. The aim of this study was to assess the dimensionality of nicotine dependence, preferably meeting the strict assumptions of the Rasch model. First, we examined the validity of the Fagerstr?m Test for Nicotine Dependence (FTND) [Br. J. Addict. 86 (1991) 1119.] in 1525 smokers who participated in a national survey considering smoking behavior. Two factors were found, suggesting that the FTND does not measure a unidimensional construct. Factor analysis of 19 other dependence items in 512 smokers resulted in four factors of which three were interpretable: compulsive smoking, social problems due to smoking, and physical dependence. We focused on smoking compulsivity. This factor turned out to consist of a four-item Rasch homogeneous scale. Two items of the FTND with face validity of smoking compulsivity were found to fit into the scale. The results of Rasch analysis were in support of a continuum of compulsivity. Difficulty refraining from smoking in places where it is forbidden was found to indicate highest compulsivity. Several correlates with smoking compulsivity were found. We conclude that compulsive smoking is one important dimension of nicotine dependence, which may account for the considerable relapse of this disorder.     

Clinical features of nicotine dependence]

Nicotine dependence is characterized by weak dependence potential and less ability to produce psychotoxicity and social disturbance. A two-compartment model consisting of "dependence" and "dependence syndrome" was used to clarify clinical features of nicotine dependence. "Dependence" was defined by drug liking. "Dependence syndrome" was defined by a compulsion to take a drug, and drug-induced pathological symptoms (withdrawal syndrome and acute disorders) and social disturbance. Nicotine produced a mild or the least degree of drug liking and withdrawal syndrome, without any significant social disturbance, or acute disorders. Thus, nicotine dependence differed from other forms of drug dependence in that nicotine was not associated with "dependence syndrome". This review also introduced other current topics of nicotine dependence. First, adolescence is regarded as a risk factor for the development of nicotine dependence, whereas the involvement of gender difference (female) in this respect is controversial. Secondly, many smokers feel difficulties in quitting smoking in spite of the weak dependence potential of nicotine, which is known as the "nicotine paradox". Several working hypotheses have been presented to explain this phenomenon. For example, nicotine has relatively strong conditioning effects and/or dependence liability compared with other drugs of abuse. However, further studies should be carried out to clarify clinical characteristics of the "nicotine paradox".     

Measuring nicotine dependence among youth: a review of available approaches and instruments

This paper reviews issues and concepts related to the measurement of nicotine dependence among youth. The primary objectives of this review are to: (1) review the measures of nicotine dependence currently being used; and (2) delineate a future research agenda in an attempt to advance the quality of measurement and instrumentation for this important research endeavor. Existing measures of nicotine dependence, including formal diagnostic interviews, related withdrawal assessments, brief self-report measures, and single-item indicators, are described. While formal diagnostic systems have been considered the 'gold standard' for evaluating dependence clinically, their specific limitations related to use for research purposes are outlined. Each broad class of measure is evaluated in terms of its rationale for use, strengths and limitations, and the extent to which it has successfully been applied to adolescent populations. A research agenda follows in the second section of the paper. In this section, the need for identification and inclusion of a standard set of optimal dependence measures, for enhancement of current measures, and for the onset of a new and comprehensive measures development program is outlined.     

Genetics of nicotine dependence and pharmacotherapy

Nicotine dependence is substantially heritable. Several regions across the genome have been implicated in containing genes that confer liability to nicotine dependence and variation in individual genes has been associated with nicotine dependence. Smoking cessation measures are also heritable, and measured genetic variation is associated with nicotine dependence treatment efficacy. Despite significant strides in the understanding of the relative contribution of genetic and environmental factors to nicotine dependence and treatment, emergent challenges necessitate interdisciplinary coordinated effort for effective problem solving. These challenges include refinement of the nicotine dependence phenotype, better understanding of the dynamic interplay between genes and environment in nicotine dependence etiology, application and development of molecular and statistical methodology that can adequately address vast amounts of data, and continuous translational cross-talk.     

Non-nicotinic neuropharmacological strategies for nicotine dependence: beyond bupropion

Smoking is a major health problem and is propelled, at least in part, by the addictive properties of nicotine. Two types of pharmacological therapies have been approved for smoking cessation by the US Food and Drug Administration. The first therapy consists of nicotine replacement, substituting the nicotine from cigarettes with safer nicotine formulations. The second therapy is bupropion (Zyban), an atypical antidepressant, whose use has raised much debate as to how a non-nicotine-based agent can aid in smoking cessation. This review focuses on recent advances that could lead to the development of improved novel pharmacological treatments. These strategies focus on altering reward processes in the brain by modulating various neurotransmitter systems: the most promising include dopamine D(3) receptor antagonists, noradrenaline reuptake inhibitors, GABA(B) receptor agonists, metabotropic glutamate 5 (mGluR5) receptor antagonists, cannabinoid CB1 receptor antagonists, and corticotropin releasing factor (CRF) 1 receptor antagonists.     

The efficacy of olanzapine for decreasing cue-elicited craving in individuals with schizophrenia and cocaine dependence: a preliminary report

OBJECTIVE: Although a growing body of research suggests that atypical neuroleptic medications are efficacious in the treatment of cocaine addiction among individuals with schizophrenia, more rigorously controlled trials are needed. To extend this research, we performed a 6-week double-blind study comparing olanzapine to haloperidol with the primary objective of reducing cue-elicited cocaine craving and the secondary aims of decreasing substance use, improving psychiatric symptoms, and determining an effect size for future studies. METHODS: Thirty-one subjects with cocaine dependence and schizophrenia were randomized to olanzapine or haloperidol, underwent a cue-exposure procedure, and completed psychiatric and substance abuse ratings. RESULTS: Individuals in the olanzapine group who completed the study had a significant reduction on the energy subscale of the Voris Cocaine Craving Scale at study completion compared with individuals in the haloperidol group. The olanzapine-treated group also had lower, but not statistically significant, PANSS General Psychopathology Subscale scores and fewer positive urine toxicology screens compared with those in the haloperidol group. CONCLUSION: This small, but rigorously controlled, pilot trial provides additional evidence for the use of atypical antipsychotics for the treatment of individuals with co-occurring schizophrenia and cocaine dependence. Reductions in craving were associated with medium to large effect sizes.     

Combination treatment for nicotine dependence: state of the science

Both nicotine replacement and sustained-release buproprion double the odds of achieving short- and moderate-term abstinence from nicotine. However, questions remain about the efficacy of combining pharmacotherapies. Our purposes were to review the evidence for (1) combined pharmacotherapy and (2) multimodal treatment combining pharmacotherapy and behavioral treatment and to recommend combinations of treatments to reduce nicotine dependence. Combining first-line pharmacotherapies with each other or with investigational drugs shows little benefit. In contrast, trials combining specific behavioral treatments with first-line pharmacotherapies show enhanced smoking cessation rates, but benefits are not seen in all populations. We recommend future directions for research, including better specification of behavioral components and further examination of the length and timing of treatment.