Cigarette smoking in a student sample: neurocognitive and clinical correlates

The role of a lifetime history of oppositional defiant and conduct disorders in adults with ADHD: implications for clinical practice

INTRODUCTION

Attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD) are frequently co-occurring disorders in children and adolescents. However, their clinical status among adults is still under discussion. This study analyzes how the current clinical presentation of adult ADHD might be influenced by a lifetime history of CD and ODD.

METHODS

We compared three groups of patients: ADHD without history of CD/ODD (n = 178), ADHD + history of ODD (n = 184), and ADHD + history of CD (n = 96).

RESULTS

A history of CD (and to a lower extent ODD) is associated with a more severe and externalizing profile.

CONCLUSION

Past CD and ODD entail a significant negative mental health impact on persistent ADHD, reinforcing the importance of actively assessing the developmental history of adult ADHD patients.

Similar hyporesponsiveness of the dorsomedial prefrontal cortex in problem gamblers and heavy smokers during an inhibitory control task

BACKGROUND

Behavioral addictions like pathological gambling share many clinical characteristics with substance dependence. In addition, both types of disorders are associated with impairments in inhibitory control. Studies in patients with substance use disorders point to hyporesponsiveness of the dorsomedial prefrontal cortex. However, no such data exist on behavioral addictions.

METHODS

Using functional magnetic resonance imaging, we investigated the neural circuitry associated with impaired response inhibition in a group of male problem gamblers (n=17) using a stop signal task. We included control conditions tailored to specifically isolate neural correlates of inhibitory control. To investigate the specificity of effects, a group of heavy smokers (n=18) and a group of healthy controls (n=17) were also included.

RESULTS

Groups did not differ in behavioral performance on the stop signal task. However, both problem gamblers and heavy smokers showed hyporesponsiveness of the dorsomedial prefrontal cortex compared to healthy controls, during successful as well as failed response inhibition. These effects were robust against adjustments for depression and adult attention deficit scores.

CONCLUSIONS

These findings suggest that hypoactivation of the inhibition circuit is a shared neural mechanism in substance use disorders and behavioral addictions. As such, they support the reclassification of pathological gambling as a behavioral addiction in DSM-V.

Differences in delay discounting between smokers and nonsmokers remain when both rewards are delayed

RATIONALE

When offered a choice between a small monetary reward available immediately (SmallNow) versus a larger reward available after a delay (LargeLater), smokers select the SmallNow alternative more than nonsmokers. That is, smokers discount the value of the LargeLater reward more than nonsmokers.

OBJECTIVES

To investigate whether this group difference was due to smokers overweighting the value of rewards available immediately compared with nonsmokers, we examined whether the group difference was also seen when both alternatives were delayed, i.e., when choosing between a SmallSoon reward and a LargeLater reward.

METHODS

In Experiment 1, smokers and nonsmokers completed a task including SmallNow versus LargeLater choices and SmallSoon versus LargeLater choices. In Experiment 2, smokers and nonsmokers completed the same task but with hypothetical choices.

RESULTS

Analyses using hyperbolic and double exponential (β-δ) models replicate prior findings that smokers discount the LargeLater reward more than nonsmokers when the smaller reward is available immediately. The smoker-nonsmoker difference was also seen when the smaller reward was slightly delayed, though this effect was primarily driven by heightened discounting in male smokers. However, for potentially real rewards only, this smoker-nonsmoker difference was significantly reduced when the smaller reward was delayed.

CONCLUSIONS

The smoker-nonsmoker difference in discounting is not confined to situations involving immediate rewards. Differences associated with potentially real versus hypothetical rewards and gender underscore the complexity of the smoking-delay discounting relationship.

Cigarette smoking in outpatients with chronic schizophrenia in Taiwan: relationships to socio-demographic and clinical characteristics

In individuals with schizophrenia, the prevalence of cigarette smoking is significantly higher than that of the general population; this appears to be associated with specific psychosocial and clinical characteristics. Indeed, some evidence suggests an increased risk of suicide among smokers with schizophrenia. The purpose of this study was to examine the characteristics of smokers with schizophrenia in Taiwan. In this cross-sectional study, 95 outpatients with DSM-IV diagnosis of schizophrenia were recruited and independently interviewed for nicotine dependency with tobacco use. The effects of cigarette smoking on the various measures, especially suicidality, were investigated. The results revealed that smokers with schizophrenia had higher rates of hospitalization, lifetime suicide attempts, antipsychotic treatment side effects, psychopathology, impulsivity, depression, anxiety, and suicidal risk than non-smokers with schizophrenia. When separate analyses were conducted in male and female patients, depressive symptoms were significant predictors of suicidality among males, whereas heavy smoking, anxious symptoms, and hopelessness were significant predictors among females. From this study, we may gain insights into the role of cigarette smoking in patients of schizophrenia in Taiwan. Furthermore, cigarette smoking may influence aspects of suicidality in schizophrenia.

Acute nicotine increases both impulsive choice and behavioural disinhibition in rats

RATIONALE

Heavy smokers exhibit greater levels of impulsive choice and behavioural disinhibition than non-smokers. To date, however, the relationship between nicotine use and differing dimensions of impulsivity has not been systematically assessed.

OBJECTIVES

A series of studies was designed to assess the acute dose-response effects of nicotine and the nicotinic receptor antagonist mecamylamine alone, and in combination with nicotine, on impulsive choice and behavioural disinhibition in rats.

METHODS

Separate groups of rats were trained on a symmetrically reinforced go/no-go task to measure levels of disinhibition and a systematic delayed reward task to measure levels of impulsive choice. Once trained, all animals in each task were treated acutely with nicotine (0.125, 0.25, 0.5 and 1.0 mg/kg), mecamylamine (0.1, 0.3 and 1.0 mg/kg) and varying doses of mecamylamine (0.1, 0.3 and 1.0 mg/kg) prior to nicotine (0.5 mg/kg). An additional experiment assessed the effects of alterations in primary motivation (presatiation and fasting) on performance in both tasks.

RESULTS

Acute nicotine increased both impulsive choice and behavioural disinhibition, effects that were blocked by pre-treatment with mecamylamine. Mecamylamine when administered alone did not alter impulsive behaviour. The lack of effect of presatiation on performance measures suggests that the observed nicotine-induced impulsivity cannot be attributed to the anorectic activity of the compound.

CONCLUSIONS

Present findings support the hypothesis that heightened impulsivity in smokers may in part be a consequence of the direct acute effects of nicotine. As such, drug-induced changes in impulsivity may play a critical role in the transition to and maintenance of nicotine dependence.

Which behavioral and personality characteristics are associated with difficulties in selective attention?

OBJECTIVE

The present study investigated the behavioral and personality profile associated with difficulties in selective attention.

METHOD

A group of participants with ADHD were assessed for ADHD behaviors. Adults with ADHD (n=22) and without ADHD (n=84) were tested on the conjunctive visual-search task for selective attention and behavioral measures, including ADHD behaviors, Big Five dimension of personality, obsessive compulsive disorder (OCD) symptoms, and sensation-seeking behavior.

RESULTS

Correlations and multiple regression analysis (group was dummy coded) showed that ADHD behaviors were not related to search performance. However, poorer search performance was related to greater neuroticism, agreeableness, introversion, lower sensation seeking, and, marginally, to OCD symptoms.

CONCLUSION

The study findings suggested that difficulties in selective attention are probably not associated with ADHD behaviors, but rather with personality traits characterized by preserving and avoiding high-stimulation behaviors.

P50 sensory gating and smoking in the general population

P50 gating is a major functional biomarker in research on schizophrenia and other psychiatric conditions with high smoking prevalence. It is used as endophenotype for studying nicotinic systems genetics and as surrogate endpoint measure for drug development of nicotinic agonists. Surprisingly, little is known about P50 gating in the general population and the relationship to smoking-related characteristics. In this multicenter study at six academic institutions throughout Germany, n=907 never-smokers (NS<20 cigarettes/lifetime), n=463 light smokers (LS) with Fagerström Test for Nicotine Dependence (FTND)≥4 and n=353 heavy smokers (HS, FTND<4) were randomly selected from the general population. As part of a standardized protocol for investigating the genetics of nicotine dependence (ND), an auditory P50 paradigm was applied. The main outcome measure was P50-amplitude difference followed by time-frequency analyses and functional imaging (sLORETA). Reduced P50 gating was found in HS compared to NS with LS taking an intermediate position-correlating with the degree of ND. sLORETA and time-frequency analyses indicate that high-frequency oscillations in frontal brain regions are particularly affected. With growing age, P50 gating increased in (heavy) smokers. This is the first large-scale study (normative sample data) on P50 sensory gating and smoking in the general population. Diminished gating of P50 and associated high-frequency oscillations in the frontal brain region are indications of a deficient inhibitory cortical function in nicotine-dependent smokers. The suitability and application of sensory P50 gating as functional biomarker with regard to genetic and pharmacological studies is discussed.

Alcohol consumption among adolescents in Kraljevo, Serbia

The aim of this study was to investigate the prevalence and predictors of alcohol consumption among adolescents in one town in Central Serbia. A questionnaire was used to obtain data from 191 Serbian students aged 18 years regarding personal experience with alcohol consumption and cigarette smoking, along with sociodemographics data. Alcohol consumption was reported by 97.4% subjects, with 34.9% having the first experience with alcohol at the age of 14 years or less. Binge drinking (the intake of five or more drinks at one sitting) was reported by 37.8% subjects. Significantly higher consumption of beer (p<0.0001) and spirits (p=0.03) was observed in boys. The most common reason for both initiation and continuation of drinking, regardless of gender, were celebrations (p≥0.12). Smokers were more likely than nonsmokers to consume all alcoholic beverages more frequently (p≤0.04) and in larger quantities (p≤0.004). More frequent or more extensive alcohol consumption, or both, was associated in boys with frequent going out and socializing (p≤0.01), close peer relationship (p=0.04), alcohol abuse within the immediate environment (p≤0.04), better financial status of family (p=0.04), and parental criticism (p≤0.02); in girls, it was associated with parental disapproval (p≤0.02), alcohol abuse within the immediate environment (p≤0.04), and general discontentedness (p=0.049). Regardless of gender, positive alcohol outcome expectancies increased alcohol consumption (p≤0.048), and negative expectancies decreased intake (p≤0.047).

Smoking and ADHD: an evaluation of self medication and behavioral disinhibition models based on comorbidity and personality patterns

OBJECTIVE

The prevalence of smoking is significantly increased among adults with Attention-Deficit/Hyperactivity Disorder (ADHD), and this association has a significant impact in both disorders, ascribed to either self-medication or behavioral disinhibition hypotheses. However, little is known about clinical variables associated with cigarette smoking among patients with ADHD. The present study evaluates comorbidity, demographic and personality profiles of patients with ADHD in relation to smoking status.

METHODS

Patients (n422) were evaluated in the adult ADHD outpatient clinic of Hospital de Clínicas de Porto Alegre. Diagnoses were based on DSM-IV criteria and interviews were performed with Portuguese version of K-SADS-E for ADHD and Oppositional-Defiant Disorder. Axis I psychiatric comorbidities were evaluated with the SCID-I and smoking behavior with Fagerström Test for Nicotine Dependence (FTND). Personality was evaluated with Cloninger's Temperament and Character Inventory (TCI).

RESULTS

The presence of smoking was strongly associated with externalizing characteristics as antisocial personality disorder (OR4.2) and substance dependence (OR6.5), but not with internalizing disorders. Moreover, smoking was associated with higher novelty seeking and lower harm avoidance scores.

CONCLUSIONS

Smoking initiation among patients with ADHD is consistent with a behavioral disinhibition profile beyond the possible role of self-medication in smoking persistence. Smoking in these patients is strongly associated with externalizing comorbid disorders.

Early adolescent executive functioning, intrauterine exposures and own drug use

Individual differences in adolescents' executive functioning are often attributed either to intrauterine substance exposure or to adolescents' own substance use, but both predictors typically have not been evaluated simultaneously in the same study. This prospective study evaluated whether intrauterine drug exposures, the adolescents' own substance use, and/or their potential interactions are related to poorer executive functioning after controlling for important contextual variables. Analyses were based on data collected on a sample of 137 predominantly African-American/African Caribbean adolescents from low-income urban backgrounds who were followed since their term birth. Intrauterine substance exposures (cocaine, marijuana, alcohol, and cigarettes) and adolescents' substance use were documented using a combination of biological assays and maternal and adolescent self-report. At 12-14 years of age, examiners masked to intrauterine exposures and current substance use assessed the adolescents using the Delis-Kaplan Executive Function System (D-KEFS), an age-referenced instrument evaluating multiple dimensions of executive functioning (EF). Results of covariate-controlled analyses in this study suggest that when intrauterine substance exposures and young adolescents' substance use variables were in the same analysis models, subtle differences in specific EF outcomes were identifiable in this non-referred sample. While further study with larger samples is indicated, these findings suggest that 1) research on adolescent substance use and intrauterine exposure research should evaluate both predictors simultaneously, 2) subtle neurocognitive effects associated with specific intrauterine drug exposures can be identified during early adolescence, and 3) intrauterine substance exposure effects may differ from those associated with adolescents' own drug use.

Deficits in inhibitory control in smokers during a Go/NoGo task: an investigation using event-related brain potentials

Introduction

The role of inhibitory control in addictive behaviors is highlighted in several models of addictive behaviors. Although reduced inhibitory control has been observed in addictive behaviors, it is inconclusive whether this is evident in smokers. Furthermore, it has been proposed that drug abuse individuals with poor response inhibition may experience greater difficulties not consuming substances in the presence of drug cues. The major aim of the current study was to provide electrophysiological evidence for reduced inhibitory control in smokers and to investigate whether this is more pronounced during smoking cue exposure.

Methods

Participants (19 smokers and 20 non-smoking controls) performed a smoking Go/NoGo task. Behavioral accuracy and amplitudes of the N2 and P3 event-related potential (ERP), both reflecting aspects of response inhibition, were the main variables of interest.

Results

Reduced NoGo N2 amplitudes in smokers relative to controls were accompanied by decreased task performance, whereas no differences between groups were found in P3 amplitudes. This was found to represent a general lack of inhibition in smokers, and not dependent on the presence of smoking cues.

Conclusions

The current results suggest that smokers have difficulties with response inhibition, which is an important finding that eventually can be implemented in smoking cessation programs. More research is needed to clarify the exact role of cue exposure on response inhibition.

Impulsiveness and venturesomeness in German smokers

INTRODUCTION

Cigarette smoking is a behavior, which is influenced by genetic, demographic, and psychological factors. A large body of research has examined the association of cigarette smoking variables with individual differences in personality traits. The aim of the current study was to replicate the findings of higher self-reported impulsivity in smokers compared with never-smokers in a German sample using Eysenck´s construct of impulsivity. Furthermore, it was intended to further the knowledge about associations between different self-reported impulsivity components and different smoking variables.

METHODS

We used the Impulsiveness-Venturesomeness-Empathy questionnaire (I7) to measure self-reported impulsiveness and venturesomeness and the Temperament and Character Inventory (TCI) to measure novelty seeking (NS) in a sample of 82 nicotine-dependent smokers and 119 never-smokers.

RESULTS

Smokers scored higher on impulsiveness, venturesomeness, and NS than never-smokers independent of age, gender, and years of education. We found a significant association between venturesomeness, impulsiveness and smoking status in daily smokers.

CONCLUSIONS

In summary, this study provides evidence that impulsiveness and venturesomeness as well as the novelty-seeking subscale extravagance are significantly associated with smoking status in a German sample of female and male smokers compared with never-smokers.

Neural correlates of response inhibition and cigarette smoking in late adolescence

Smoking is usually initiated in adolescence, and is the leading preventable cause of death in the United States. Little is known, however, about the links between smoking and neurobiological function in adolescent smokers. This study aimed to probe prefrontal cortical function in late adolescent smokers, using a response inhibition task, and to assess possible relationships between inhibition-related brain activity, clinical features of smoking behavior, and exposure to cigarette smoking. Participants in this study were otherwise healthy late adolescent smokers (15-21 years of age; n=25), who reported daily smoking for at least the 6 months before testing, and age- and education-matched nonsmokers (16-21 years of age; n=25), who each reported smoking fewer than five cigarettes in their lifetimes. The subjects performed the Stop-signal Task, while undergoing functional magnetic resonance imaging. There were no significant group differences in prefrontal cortical activity during response inhibition, but the Heaviness of Smoking Index, a measure of smoking behavior and dependence, was negatively related to neural function in cortical regions of the smokers. These findings suggest that smoking can modulate prefrontal cortical function. Given the late development of the prefrontal cortex, which continues through adolescence, it is possible that smoking may influence the trajectory of brain development during this critical developmental period.

Emotional and affective temperaments and cigarette smoking in a large sample

BACKGROUND

Tobacco use has been associated with externalized personality traits. Our aim was to evaluate the association of smoking with emotional and affective temperaments in a large sample.

METHODS

In this cross-sectional web-based survey, volunteers completed the Combined Emotional and Affective Temperament Scale (CEATS), which assesses emotional (fear, drive, anger, and control) and affective temperaments (e.g. cyclothymic, irritable), and questions about smoking.

RESULTS

Among the 5379 subjects (1370 males), there were 60% non-smokers, 17% quitters and 23% current smokers. Non-smokers had higher fear and control and lower anger than quitters and smokers, and higher drive than smokers. Quitters had higher drive and control and lower anger than smokers. Smoking was lower among apathetics, depressives, euthymics and hyperthymics and higher in cyclothymics and labiles. Lower drive and higher anger were associated with heavier smoking. Less adaptive temperament was related to higher prevalence of and heavier smoking.

LIMITATIONS

The data was collected from a convenience sample by the internet, and most volunteers assessed the instrument through a psychoeducational website for bipolar spectrum disorders, leading to a higher proportion of cyclothymics; the assessment of smoking habits was limited to two questions; the study was cross-sectional.

CONCLUSIONS

Smoking was associated with lower fear, control and drive, higher anger and unstable externalized affective temperaments. Lower control and higher anger were associated with being a heavy smoker and current smoking. Assessment of temperament may help decision about treatments for smoking cessation.

Aetiology and risk factors of musculoskeletal disorders in physically active conscripts: a follow-up study in the Finnish Defence Forces

BACKGROUND

Musculoskeletal disorders (MSDs) are the main reason for morbidity during military training. MSDs commonly result in functional impairment leading to premature discharge from military service and disabilities requiring long-term rehabilitation. The purpose of the study was to examine associations between various risk factors and MSDs with special attention to the physical fitness of the conscripts.

METHODS

Two successive cohorts of 18 to 28-year-old male conscripts (N = 944, median age 19) were followed for six months. MSDs, including overuse and acute injuries, treated at the garrison clinic were identified and analysed. Associations between MSDs and risk factors were examined by multivariate Cox's proportional hazard models.

RESULTS

During the six-month follow-up of two successive cohorts there were 1629 MSDs and 2879 health clinic visits due to MSDs in 944 persons. The event-based incidence rate for MSD was 10.5 (95% confidence interval (CI): 10.0-11.1) per 1000 person-days. Most MSDs were in the lower extremities (65%) followed by the back (18%). The strongest baseline factors associated with MSDs were poor result in the combined outcome of a 12-minute running test and back lift test (hazard ratio (HR) 2.9; 95% CI: 1.9-4.6), high waist circumference (HR 1.7; 95% CI: 1.3-2.2), high body mass index (HR 1.8; 95% CI: 1.3-2.4), poor result in a 12-minute running test (HR 1.6; 95% CI: 1.2-2.2), earlier musculoskeletal symptoms (HR 1.7; 95% CI: 1.3-2.1) and poor school success (educational level and grades combined; HR 2.0; 95% CI: 1.3-3.0). In addition, risk factors of long-term MSDs (>or=10 service days lost due to one or several MSDs) were analysed: poor result in a 12-minute running test, earlier musculoskeletal symptoms, high waist circumference, high body mass index, not belonging to a sports club and poor result in the combined outcome of the 12-minute running test and standing long jump test were strongly associated with long-term MSDs.

CONCLUSIONS

The majority of the observed risk factors are modifiable and favourable for future interventions. An appropriate intervention based on the present study would improve both aerobic and muscular fitness prior to conscript training. Attention to appropriate waist circumference and body mass index would strengthen the intervention. Effective results from well-planned randomised controlled studies are needed before initiating large-scale prevention programmes in a military environment.

Smoking outcome expectancies mediate the association between sensation seeking, peer smoking, and smoking among young adolescents

BACKGROUND

Sensation seeking is a strong correlate of smoking among adolescents, yet the research on mediators of this association is not well established. The proposed model of the present study includes antecedent variables (sensation seeking), mediators (perceived peer smoking, outcome expectancies including negative consequences, positive reinforcement, negative reinforcement, and appetite-and-weight control), and one outcome variable (smoking cigarettes during the past 30 days).

METHODS

Self-reported data obtained from Hungarian high-school students (ninth grade, N = 2,565, mean age 15.3 years, SD = 0.56) were analyzed with structural equation modeling. Before testing of the main model, the construct validity of mediators (outcome expectancy scales) was supported with confirmatory factor analysis (CFA) and structural equation modeling. The final model was tested with structural equation modeling, and the goodness-of-fit indices and the proportion of direct and indirect effects were analyzed.

RESULTS

Our mediational model had an excellent model fit, and this study supported both the proposed sensation seeking-->positive and negative reinforcement-->smoking behavior pathways and sensation seeking-->perceived peer smoking-->positive and negative reinforcement-->smoking behavior pathways. The total indirect effect explains 76% of sensation seeking and smoking association. Results support the notion that positive and negative reinforcement expectancies mediate between sensation seeking and smoking.

DISCUSSION

Results support the notion that perceived peer smoking, positive and negative reinforcement expectancies mediate between sensation seeking and smoking.

Differential contribution of genetic variation in multiple brain nicotinic cholinergic receptors to nicotine dependence: recent progress and emerging open questions

Nicotine dependence (ND), a major public health challenge, is a complex, multifactorial behavior, in which both genetic and environmental factors have a role. Brain nicotinic acetylcholine receptor (nAChR)-encoding genes are among the most prominent candidate genes studied in the context of ND, because of their biological relevance as binding sites for nicotine. Until recently, most research on the role of nAChRs in ND has focused on two of these genes (encoding the alpha4- and beta2-subunits) and not much attention has been paid to the possible contribution of the other nine brain nAChR subunit genes (alpha2-alpha3, alpha5-alpha7, alpha9-alpha10, beta3-beta4) to the pathophysiology and genetics of ND. This situation has changed dramatically in the last 2 years during which intensive research had addressed the issue, mainly from the genetics perspective, and has shown the importance of the CHRNA5-CHRNA3-CHRNB4 and CHRNA6-CHRNB3 loci in ND-related phenotypes. In this review, we highlight recent findings regarding the contribution of non-alpha4/beta2-subunit containing nAChRs to ND, based on several lines of evidence: (1) human genetics studies (including linkage analysis, candidate-gene association studies and whole-genome association studies) of several ND-related phenotypes; (2) differential pharmacological and biochemical properties of receptors containing these subunits; (3) evidence from genetically manipulated mice; and (4) the contribution of nAChR genes to ND-related personality traits and neurocognitive profiles. Combining neurobiological genetic and behavioral perspectives, we suggest that genetic susceptibility to ND is not linked to one or two specific nAChR subtype genes but to several. In particular, the alpha3, alpha5-6 and beta3-4 nAChR subunit-encoding genes may play a much more pivotal role in the neurobiology and genetics of ND than was appreciated earlier. At the functional level, variants in these subunit genes (most likely regulatory) may have independent as well as interactive contributions to the ND phenotype spectrum. We address methodological challenges in the field, highlight open questions and suggest possible pathways for future research.

Affective decision-making deficits, linked to a dysfunctional ventromedial prefrontal cortex, revealed in 10th-grade Chinese adolescent smokers

This study addressed the question of whether poor decision making would be associated with adolescent past 7-day smoking. We conducted a cross-sectional study of 208 10th-grade adolescents in Chengdu City, China. We used the Iowa Gambling Task (IGT) to assess decision-making, and the Self-ordered Pointing Task (SOPT) to assess working memory capacity. Paper and pencil questionnaires assessed the school academic performance (SAP) and smoking variables. The results showed that a significantly higher proportion of past 7-day smokers (91.7%) were susceptible to future smoking and cigarette offers from best friends compared to other levels of smokers (never, ever and past 30-day smokers). Consistent with these behavioral data, the neuropsychological assessments revealed that relative to never smokers, past 7-day adolescent smokers (but not ever smokers or past 30-day smokers) demonstrated significantly lower scores on the IGT. Moreover, a higher proportion of past 7-day smokers (91.7%) performed poorly (no more than an overall net score of 10) on the IGT than nonsmokers and irregular (ever or past 30-day) smokers (about 65.3%). There were no differences on working memory performance for smokers (at any level) compared to never smokers after adjusting for school-type. In addition, logistic regression showed that the IGT significantly predicted past 7-day smoking after controlling for the working memory, school academic performance and demographic variables. These results suggest that poor affective decision making might predispose some adolescents to smoking in the future or in the social situations where their peers are smoking. Intervention targeting affective decision making might hold promise for reducing adolescents' risks for substance use.

Post-combat invincibility: violent combat experiences are associated with increased risk-taking propensity following deployment

Combat exposure is associated with increased rates of mental health problems such as post-traumatic stress disorder, depression, and anxiety when Soldiers return home. Another important health consequence of combat exposure involves the potential for increased risk-taking propensity and unsafe behavior among returning service members. Survey responses regarding 37 different combat experiences were collected from 1252 US Army Soldiers immediately upon return home from combat deployment during Operation Iraqi Freedom. A second survey that included the Evaluation of Risks Scale (EVAR) and questions about recent risky behavior was administered to these same Soldiers 3 months after the initial post-deployment survey. Combat experiences were reduced to seven factors using principal components analysis and used to predict post-deployment risk-propensity scores. Although effect sizes were small, specific combat experiences, including greater exposure to violent combat, killing another person, and contact with high levels of human trauma, were predictive of greater risk-taking propensity after homecoming. Greater exposure to these combat experiences was also predictive of actual risk-related behaviors in the preceding month, including more frequent and greater quantities of alcohol use and increased verbal and physical aggression toward others. Exposure to violent combat, human trauma, and having direct responsibility for taking the life of another person may alter an individual's perceived threshold of invincibility and slightly increase the propensity to engage in risky behavior upon returning home after wartime deployment. Findings highlight the importance of education and counseling for returning service members to mitigate the public health consequences of elevated risk-propensity associated with combat exposure.

The role of impulsive behavior in drug abuse

BACKGROUND

Impulsivity is a multifaceted construct that has recently been recognized as a factor contributing to enhanced vulnerability to drug abuse.

OBJECTIVES

In the present review, we focus on two facets of impulsivity (and tasks that measure them): (1) impulsive choice (delay discounting task) and (2) inhibitory failure (go/no-go, stop signal reaction time, and five-choice serial reaction time tasks). We also describe how performance on each of these tasks is associated with drug-related behavior during phases of drug abuse that capture the essential features of addiction (acquisition, escalation, and reinstatement of drug-seeking after drug access has terminated). Three hypotheses (H) regarding the relationship between impulsivity and drug abuse are discussed: (1) increased levels of impulsivity lead to drug abuse (H1), (2) drugs of abuse increase impulsivity (H2), and (3) impulsivity and drug abuse are associated through a common third factor (H3).

CONCLUSION

Impulsivity expressed as impulsive choice or inhibitory failure plays a role in several key transition phases of drug abuse. There is evidence to support all three nonexclusive hypotheses. Increased levels of impulsivity lead to acquisition of drug abuse (H1) and subsequent escalation or dysregulation of drug intake. Drugs of abuse may increase impulsivity (H2), which is an additional contributor to escalation/dysregulation. Abstinence, relapse, and treatment may be influenced by both H1 and H2. In addition, there is a relationship between impulsivity and other drug abuse vulnerability factors, such as sex, hormonal status, reactivity to nondrug rewards, and early environmental experiences that may impact drug intake during all phases of addiction (H3). Relating drug abuse and impulsivity in phases of addiction via these three hypotheses provides a heuristic model from which future experimental questions can be addressed.

P50 sensory gating and attentional performance

Sensory gating refers to the preattentional filtering of irrelevant sensory stimuli. This process may be impaired in schizotypy, which is a trait also associated with cigarette smoking. This association may in part stem from the positive effects of smoking on sensory gating and attention. The relationship among sensory gating, smoking, schizotypy and attention was examined in 39 undergraduates. Sensory gating was indexed by the P50 suppression paradigm, and attention was measured by the Attention Network Test (ANT) and a Stroop task. Results showed sensory gating to be positively correlated with performances on ANT and Stroop reflected in better alerting, less conflict between stimuli, faster reaction time, and greater accuracy. Smokers showed a pattern of a greater number of significant correlations between sensory gating and attention in comparison to non-smokers, although the relationship between sensory gating and attention was not affected by schizotypy. The majority of significant correlations were found in the region surrounding Cz. These findings are discussed relative to the potential modifying influence of smoking and schizotypy on sensory gating and attention.

Impulsivity as a vulnerability marker for substance-use disorders: review of findings from high-risk research, problem gamblers and genetic association studies

There is a longstanding association between substance-use disorders (SUDs) and the psychological construct of impulsivity. In the first section of this review, personality and neurocognitive data pertaining to impulsivity will be summarised in regular users of four classes of substance: stimulants, opiates, alcohol and 3,4-methylenedioxymethamphetamine (MDMA). Impulsivity in these groups may arise via two alternative mechanisms, which are not mutually exclusive. By one account, impulsivity may occur as a consequence of chronic exposure to substances causing harmful effects on the brain. By the alternative account, impulsivity pre-dates SUDs and is associated with the vulnerability to addiction. We will review the evidence that impulsivity is associated with addiction vulnerability by considering three lines of evidence: (i) studies of groups at high-risk for development of SUDs; (ii) studies of pathological gamblers, where the harmful consequences of the addiction on brain structure are minimised, and (iii) genetic association studies linking impulsivity to genetic risk factors for addiction. Within each of these three lines of enquiry, there is accumulating evidence that impulsivity is a pre-existing vulnerability marker for SUDs.

Smoking, psychosocial factors, psychopathologic behavior, and other related conditions in hospitalized youth suicide attempters

BACKGROUND

Comorbidity of suicidal behavior with various risk factors has been reported. This study examines the combined effect and the interactions of the most prominent risk factors in hospitalized suicide attempters.

METHOD

Seventy-six successive hospitalized suicide attempters and 76 matched control subjects, 9 to 20 years old, were subjected to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I and Axis II diagnoses and were interviewed for the use of licit and illicit substances. Also, 18 control subjects with the same psychiatric disorders diagnosed in the attempters were examined. Logistic regression analysis was applied to determine the independent effect of the risk factors to suicide attempts.

RESULTS

The findings showed an 18-fold greater frequency of psychiatric disorders, a 14-fold greater frequency of other conditions that may be a focus of clinical attention (mainly relational problems), a 9.7-fold greater frequency of smoking, and a 4.7-fold greater frequency of psychosocial and environmental problems in the attempters than in the control subjects. The independent association of these factors with increased suicide risk persisted after adjusting for the effect of other factors.

CONCLUSIONS

Psychopathologic behavior, psychosocial factors, and smoking are independently associated with increased risk for serious suicide attempts.

Adolescent environmental tobacco smoke exposure predicts academic achievement test failure

PURPOSE

Research has linked prenatal tobacco exposure to neurocognitive and behavioral problems that can disrupt learning and school performance in childhood. Less is known about its effects on academic achievement in adolescence when controlling for known confounding factors (e.g., environmental tobacco smoke [ETS]). We hypothesized that prenatal tobacco exposure would decrease the likelihood of passing academic achievement tests taken at 16 and 18 years of age.

METHODS

This study was a longitudinal analysis of birth cohort data including 6,380 pregnant women and offspring from the 1958 National Child Development Study (NCDS). Academic pass/fail performance was measured on British standardized achievement tests ("Ordinary Level" [O-Level] and Advanced Level: [A-Level]). Prenatal tobacco exposure plus controlling variables (ETS, teen offspring smoking and gender, maternal age at pregnancy, maternal smoking before pregnancy, and socioeconomic status) were included in regression models predicting O- and A-Level test failure.

RESULTS

Significant predictors of test failure in the O-Level model included exposure to maternal (OR = 0.71, p < .0001) and paternal (OR = 0.70, p < .0001) ETS, as well as teen smoking, female gender, and lower SES. Prenatal tobacco exposure did not influence failure. Similar factors emerged in the A-Level model except that male gender contributed to likelihood of failure. Prenatal exposure remained nonsignificant.

CONCLUSIONS

Our model suggests that adolescent exposure to ETS, not prenatal tobacco exposure, predicted failure on both O- and A-Level achievement tests when controlling for other factors known to influence achievement. Although this study has limitations, results bolster growing evidence of academic-related ETS consequences in adolescence.

Características psicológicas associadas ao comportamento de fumar tabaco

Este artigo apresenta uma revisão da literatura sobre a psicologia do tabagismo, destacando características de personalidade do fumante como um dos obstáculos à cessação do tabagismo. Descreve-se a relação entre tabagismo e personalidade e, a seguir, a relação do tabagismo com os principais transtornos psiquiátricos. Estudos revelam que os fumantes tendem a ser mais extrovertidos, ansiosos, tensos, impulsivos e com mais traços de neuroticismo e psicoticismo, em comparação a ex-fumantes e não fumantes. A literatura revela, ainda, forte associação entre tabagismo e transtornos mentais, como esquizofrenia e depressão, entre outros. A compreensão dos fatores de natureza psicológica associados ao consumo e à dependência pode contribuir para a elaboração e aperfeiçoamento de estratégias terapêuticas para o tratamento da dependência e/ou programas de cunho educativo/preventivo.

Why do young women smoke? V. Role of direct and interactive effects of nicotinic cholinergic receptor gene variation on neurocognitive function

Previous work suggests that young women who smoke cigarettes regularly, or did so in the past, manifest a neurocognitive profile that is characterized by small but significant impairments of response inhibition and attention. The present study sought to determine whether variation in nicotinic cholinergic receptor (nAchR) genes impacts upon cognitive function in these domains by overall or differential effects on the performance of current, former and non-smokers. The study sample consisted of 100 female college students, current or past smokers, and 144 who had never smoked. All performed a computerized neurocognitive test battery and were genotyped for 39 single nucleotide polymorphisms in 11 nAchR genes. The results, derived from linear or logistic regression, show significant direct and interactive relationships between single nucleotide polymorphisms and haplotypes in several nAchR genes and performance on the Matching Familiar Figures Test (MFFT) Stroop test, Continuous Performance Task (CPT) and Tower of London (TOL) test. Response inhibition (MFFT, Stroop, CPT Loading Phase, TOL) was associated with variants in CHRNA2, CHRNA4, CHRNA5, CHRNA7, CHRNA9, CHRNA10, CHRNB2 and CHRNB3. Selective attention (Stroop) was associated with CHRNA4, CHRNA5, CHRNA9 and CHRNB2. Sustained attention (CPT Boring Phase) was associated with CHRNA4, CHRNA5, CHRNA7, CHRNA10 and CHRNB3. Up to 37% of the variance among the smokers and up to 47% of the variance among the non-smokers on the test measures was explained. Differences between smokers and non-smokers in neurocognitive function, putatively implicated in susceptibility to nicotine dependence, may be modulated by variants in nAchR genes, with potential implications for prevention and treatment.

Which dimensions of impulsivity are related to cigarette craving?

Cigarette smoking is a very important health problem and represents the largest preventable risk factor for premature death in developed countries. A considerable body of research indicates that impulsivity is a central etiological concept in many theoretical models of tobacco addiction. The aim of this study is to analyse which dimensions of impulsivity are related to cigarette craving. To this end, 40 undergraduate psychology students were screened using the revised Questionnaire on Smoking Urges (QSU-12) and the French adaptation of the UPPS Impulsive Behavior Scale (UPPS). This scale identifies four distinct components associated with impulsive behaviour: urgency, lack of premeditation, lack of perseverance, and sensation seeking. The results showed that urgency is a significant predictor of tobacco cravings, while depression and anxiety are not.

Cigarette smoking and the risk for alcohol use disorders among adolescent drinkers

BACKGROUND

Cigarette smoking and alcohol use disorders (AUDs) are closely linked, but it is not clear whether higher rates of AUD among smokers are solely attributable to heavier drinking or, alternatively, whether smokers are more vulnerable to alcohol abuse and dependence than nonsmokers who drink comparable quantities. We sought to address this issue using data from a nationally representative U.S. sample of adolescents and young adults. Specifically, we analyzed the relationship between cigarette smoking, drinking, and AUDs.

METHODS

Data were from the aggregated 2002 through 2004 U.S. National Survey on Drug Use and Health. Participants were randomly selected, household-dwelling adolescents and young adults (ages 12-20) from the noninstitutionalized, civilian population of the United States (N=74,836). Measurements included current DSM-IV alcohol abuse or dependence, number of drinks in the past 30 days, and past-year cigarette smoking, defined as having smoked more than 100 cigarettes across the lifetime and having smoked during the past year.

RESULTS

Past-year smokers (prevalence=16.0%) drank in higher quantities than never-smokers, but were also at elevated risk for AUD when compared with never-smokers who drank equivalent quantities. The effect was observed across age groups, but was more prominent among younger adolescents. After adjusting for drinking quantity and sociodemographic variables, smokers had 4.5-fold higher odds of AUD than never-smokers [95% confidence interval (95% CI), 3.1-6.6]. Youths who reported smoking but did not cross the 100-cigarette threshold were at intermediate risk [odds ratio (OR), 2.3; 95% CI, 1.7-3.3]. Differences in AUD between smokers and never-smokers were most pronounced at lower levels of drinking.

CONCLUSIONS

The results are consistent with a higher vulnerability to AUDs among smokers, compared with nonsmokers who drink equivalent quantities.

Increased suicidal risk among smoking schizophrenia patients

INTRODUCTION

Schizophrenia patients display a high suicidal risk, although this risk is difficult to predict. One of the variables associated with increased suicide risk is smoking. In the present study, we assessed the suicidal risk in schizophrenia patients, smokers and nonsmokers. We also evaluated the impact of various variables such as psychotic symptoms, impulsivity, and extra-pyramidal side effects on suicidal risk.

METHODS

Sixty-one schizophrenia patients responded to a battery of measures, including the suicidal risk scale (SRS), the positive and negative syndrome scale (PANSS), the impulsivity control scale, and the Simpson Angus Scale for extrapyramidal side effects. The effect of smoking on the various measures, especially suicidal risk, was examined.

RESULTS

Schizophrenia patients who smoke obtained higher PANSS scores (both total score and positive and negative subscales), but did not differ on the Simpson Angus scale of extrapyramidal side effects. They also exhibited higher suicide risk as reflected by higher scores on the SRS, and a trend for higher impulsivity as measured by the impulsivity control scale. Women that smoked had higher SRS scores as compared with female nonsmokers, and also higher than in males, smokers and nonsmokers. Smoking and a history of suicide attempt predicted in our regression analysis a higher SRS score. When conducting separate analyses for the male and female patients, the significant contributors were the PANSS total score among the males and the number of pack-years among the female patients.

CONCLUSIONS

Despite hints toward the role of smoking in suicidal behavior in Schizophrenia, especially among female patients, more studies are needed to elucidate the association between smoking and suicidality in schizophrenia patients.

Association between P3 event-related brain potential amplitude and adolescent problem behavior

This study examined P3 event-related brain potential amplitude and the age of onset of adolescent problem behaviors associated with the development of externalizing psychopathology. Five hundred and one male and 627 female 17-year-old twins reported whether and when they had initiated tobacco, alcohol, or illicit drug use, had police contact, or had sexual intercourse. P3 amplitude was recorded using a visual oddball task. Each of these behaviors was associated with reduced P3 amplitude. When these five behaviors were used to create a composite early problem behavior scale reflecting onset prior to age 15, higher scores were associated with smaller P3 amplitudes. P3 amplitude reduction has been associated with genetic risk for alcoholism and other externalizing disorders associated with disinhibited behavior. Our results suggest that reduced P3 may also be associated with early expression of behaviors that predict the development of these disorders.

Smoking is associated with neurocognitive deficits in alcoholism

BACKGROUND

Impaired problem solving, visual-spatial processing, memory, and cognitive proficiency are consequences of severe alcoholism. Smoking is much more prevalent among alcoholics than the general population, yet the possible neurocognitive effects of cigarette smoking in alcoholism have not been studied, despite evidence that long-term smoking is associated with neurocognitive deficits.

OBJECTIVE

Determine whether smoking contributes to neurocognitive deficits associated with alcoholism.

DESIGN

Neurocognitive function was examined in a community-recruited (n=172) sample of men. Alcohol problems/alcoholism were measured by the lifetime alcohol problems score (LAPS), DSM-IV diagnosis, and monthly drinking rate. Smoking was measured in pack-years. Neurocognitive function was measured with IQ (short version of WAIS-R), and cognitive proficiency (fast, accurate performance).

RESULTS

Both alcoholism and smoking were negatively correlated with neurocognitive function. When alcoholism and smoking were included in regression models, smoking remained a significant predictor for both measures, but alcoholism remained significant only for IQ.

CONCLUSIONS

Both smoking and alcoholism were related to neurocognitive function. Smoking may explain some of the relationship between alcoholism and neurocognitive function, perhaps especially for measures that focus on proficiency. Future studies are necessary to more fully understand the effects of smoking on neurocognitive function in alcoholism.

Nicotine psychobiology: how chronic-dose prospective studies can illuminate some of the theoretical issues from acute-dose research

RATIONALE

To illustrate how prospective cigarette smoking research can illuminate some of the theoretical dilemmas about nicotine psychobiology from acute dose research.

METHODS AND RESULTS

When briefly deprived smokers are administered nicotine, they display a range of psychobiological 'gains', with improved cognitive performance, feelings of contentment, and reduced feelings of stress or depression. However, abstinence leads to decrements in all these functions. The balance between the deficits of nicotine deprivation and the gains of reinstatement has been debated for decades. Yet, it still remains controversial whether nicotine is psychobiologically beneficial, neutral or detrimental. Some illumination may be provided by prospective research. Taking up smoking during adolescence is often followed by increased feelings of stress and depression, whereas quitting is often associated with subsequent mood gains. Short-term prospective studies reveal that the essence of nicotine dependency is repetitive psychobiological vascillation. The mood gains of smoke inhalation represent the temporary reversal of abstinence effects, and the frequent experience of negative states in between cigarettes explains why smoking can increase psychobiological distress. This may also be linked with Diathesis-Stress models. If withdrawal symptoms reflect the exacerbation of natural predispositions, then 'disadvantaged' smokers will suffer the worst abstinence symptoms and develop the strongest nicotine dependency. This explanation contrasts with the self-medication model, which focuses on the immediate benefits of smoke inhalation, rather than the overall costs of nicotine use.

CONCLUSIONS

The frequent experience of negative psychological states in between cigarettes helps to explain why nicotine dependency is associated with a range of psychobiological problems.

Differences in impulsivity and sensation seeking between early- and late-onset alcoholics

The personality traits of impulsivity and sensation seeking have been proposed as important features of early-onset alcoholism. Early-onset (EOA, n=62) and late-onset (LOA, n=68 ) alcoholic inpatients were compared as to the severity of their substance use and related problems, and self-report scales measuring impulsivity (Barratt Impulsiveness Scale, version 11), sensation seeking (Sensation Seeking Scale), and aggressiveness (Buss Durkee Hostility Inventory). The symptom severity of the EOAs' alcohol-use disorder and related problems was higher than that of the LOAs. Furthermore, the EOAs had higher levels of impulsivity, sensation seeking, and aggression relative to the LOAs. The differences in impulsivity remained after an analysis controlling for the effect of aggressiveness. Finally, cigarette smoking was positively correlated with impulsiveness across alcoholic subgroups. Active screening for impulsive traits in treatment-seeking alcohol-abusing populations is recommended to improve treatment planning and prevent early drop-out.

Psychobiological correlates of smoking in patients with erectile dysfunction

Although it is clear that cigarette abuse is closely linked to sexual dysfunction, it is still unclear which are the psychobiological correlates of smoking among individuals with sexual dysfunction. The aim of the present study is the assessment of the organic, psychogenic and relational correlates of erectile dysfunction (ED) in outpatients with different smoking habits. We studied the psychobiological correlates of smoking behaviour in a consecutive series of 1150 male patients, seeking medical care for ED. All patients were investigated using a Structured Interview (SIEDY), which explores the organic, relational and intra-psychic components of ED, and a self-administered questionnaire for general psychopathology (MHQ). In addition, several biochemical and instrumental parameters were studied, to clarify the biological components underlying ED. Current smokers (CS) showed a higher activation of the hypothalamus-pituitary-testis axis (higher LH, testosterone and right testicular volume) and lower levels of both prolactin and TSH. Hormonal changes were reverted after smoking cessation. CS showed a higher degree of somatized anxiety and were more often unsatisfied of their occupational and domestic lifestyle. Smoking, as part of a risky behaviour, was significantly associated with abuse of alcohol and cannabis. Both CS and past smokers (PS) showed an impairment of subjective and objective (dynamic peak systolic velocity at penile duplex ultrasound) erectile parameters. This might be due to a direct atherogenic effect of smoking, a cigarette-induced alteration of lipid profile (higher triglyceride and lower HDL cholesterol in CS than in non-smokers or PS), or due to a higher use of medications potentially interfering with sexual function. This is the first comprehensive evaluation of the biological and intrapsychic correlates to the smoking habit. Our report demonstrates that smoking has a strong negative impact on male sexual life, even if it is associated at an apparently more sexual-favourable hormonal milieu.

Measuring impulsivity and modeling its association with cigarette smoking

Two types of behavioral measure are primarily used to examine impulsivity in humans and animals: Go/No-go tasks to assess inhibition and relative preference tasks to assess delay aversion. Several examples of each type of task are described so that common cognitive processes and variables affecting performance can be identified. Data suggest that smokers are more impulsive on each of these impulsivity measures than nonsmokers. Several models can be proposed to account for this group difference: (a) the differences predate and, possibly, are causally related to the initiation of cigarette smoking; (b) higher levels of impulsivity are associated with continued smoking, either through an association with heightened positive subjective effects of nicotine or heightened negative effects of nicotine abstinence (withdrawal); (c) nicotine causes neuroadaptations that result in elevated impulsivity in smokers. Studies relating to each of these models are reviewed, and it is concluded that all three models may contribute to the observed higher levels of impulsivity in smokers. However, pertinent studies are limited and additional systematic research is needed.

Epidemiology and etiology of adolescent smoking

PURPOSE OF REVIEW

Despite the socioeconomic and personal health costs directly attributed to smoking, over one-half of high school seniors have used cigarettes, and over 15% of seniors are daily smokers. This review summarizes the recent research concerning the psychosocial and physiologic risk and protective factors associated with adolescent smoking.

RECENT FINDINGS

Studies of the psychosocial risk factors have added to the evidence that stress, peers and family influences, ethnicity, and depression all serve as risk factors for the development and maintenance of smoking in adolescents. Protective factors include parental expectations and monitoring, religious activity, and sociopolitical factors, such as tobacco-related marketing bans and higher cigarette taxes. Adolescent smoking trajectories have been further defined and can be used to classify smokers in terms of dependence symptoms. Finally, neurobiological research has focused to a large extent on the concept of disinhibition as a risk factor for smoking in adolescents.

SUMMARY

While rates of smoking in adolescents have declined since 1997, millions of adolescents initiate or continue smoking each year, with deleterious health and psychosocial consequences. Research into the risk and protective factors for adolescent smoking, particularly that which ties psychosocial and neurobiological factors together, is necessary to inform the development of tailored and maximally efficacious treatments for this population.