Smoking cessation and inattention or hyperactivity/impulsivity: a post hoc analysis

A phenome-wide association study of polygenic scores for attention deficit hyperactivity disorder across two genetic ancestries in electronic health record data

Testing the association between genetic scores for Attention Deficit Hyperactivity Disorder (ADHD) and health conditions, can help us better understand its complex etiology. Electronic health records linked to genetic data provide an opportunity to test whether genetic scores for ADHD correlate with ADHD and additional health outcomes in a health care context across different age groups. We generated polygenic scores (ADHD-PGS) trained on summary statistics from the latest genome-wide association study of ADHD (N = 55,374) and applied them to genome-wide data from 12,383 unrelated individuals of African-American ancestry and 66,378 unrelated individuals of European ancestry from the Vanderbilt Biobank. Overall, only Tobacco use disorder (TUD) was associated with ADHD-PGS in the African-American ancestry group (Odds ratio [95% confidence intervals] = 1.23[1.16-1.31], p = 9.3 × 10-09 ). Eighty-six phenotypes were associated with ADHD-PGS in the European ancestry individuals, including ADHD (OR[95%CIs] = 1.22[1.16-1.29], p = 3.6 × 10-10 ), and TUD (OR[95%CIs] = 1.22[1.19-1.25], p = 2.8 × 10-46 ). We then stratified outcomes by age (ages 0-11, 12-18, 19-25, 26-40, 41-60, and 61-100). Our results suggest that ADHD polygenic scores are associated with ADHD diagnoses early in life and with an increasing number of health conditions throughout the lifespan (even in the absence of ADHD diagnosis). This study reinforces the utility of applying trait-specific PGSs to biobank data, and performing exploratory sensitivity analyses, to probe relationships among clinical conditions.

The contribution of positive affect and loneliness on readiness and self-efficacy to quit smoking among Spanish-speaking Mexican American smokers

BACKGROUND

The existing research on affective and interpersonal determinants of smoking cessation largely under-represents minority smokers, such as Latinos.

OBJECTIVE

The current study examined associations between affective and interpersonal factors with intermediary smoking cessation variables among Mexican-American smokers (N = 290; 60% male).

METHODS

Measures of positive and negative affect, social support, and loneliness were each examined for associations with measures of motivational readiness to quit smoking, and smoking abstinence self-efficacy. Significant predictors were entered into models simultaneously to examine their unique associations. Covariates included gender, age, and educational attainment.

RESULTS

Negative affect (b = .68, SE b = .14, p < .001) and loneliness (b = .20, SE b = .09, p < .05) were independently associated with motivation. Negative affect (b = .20, SE b = .06, p < .01) and positive affect (b = .34 SE b = .07, p < .001) were independently associated with self-efficacy. In the final models, only negative affect was associated with motivation (b = .68, SE b = .17, p < .001); whereas negative (b = .17, SE b = .06, p < .01) and positive (b = . 32, SE b = .07, p < .001) affect were associated with self-efficacy.

CONCLUSION

Results highlight the importance of resilience factors (e.g., positive affect) among Mexican-American smokers. Cessation interventions regularly target negative affect among smokers; additional focus on positive affect in cessation interventions with this population may be warranted.

Association of Attention-Deficit/Hyperactivity Disorder With E-Cigarette Use

INTRODUCTION

E-cigarette use in young people has emerged as a public health concern in the U.S. Previous studies have shown that individuals with attention-deficit/hyperactivity disorder are more likely to use conventional cigarettes. However, little is known about their use of E-cigarettes. This study examines the association of attention-deficit/hyperactivity disorder with E-cigarette and other tobacco product use among undergraduate and graduate students in the U.S.

METHODS

This study included data from 195,443 U.S. undergraduate and graduate students aged 18-39 years who participated in the National College Health Assessment surveys from spring 2017 to fall 2018. History of attention-deficit/hyperactivity disorder diagnosis and current use of conventional cigarettes, E-cigarettes, and other tobacco products were ascertained by questionnaires. Logistic regression models estimated the ORs and 99% CIs of use of conventional cigarettes, E-cigarettes, and other tobacco products according to attention-deficit/hyperactivity disorder history.

RESULTS

Among the 195,443 students, 16,800 (8.35%) were current conventional cigarette users and 15,863 (7.89%) were current E-cigarette users; 16,283 (8.10%) had a history of attention-deficit/hyperactivity disorder diagnosis. After adjustment for demographics, socioeconomics, lifestyle factors, BMI, anxiety, and depression, the OR of E-cigarette use among participants with attention-deficit/hyperactivity disorder, compared with those without attention-deficit/hyperactivity disorder, was 1.72 (99% CI=1.60, 1.85), which was comparable to the magnitude of associations for other tobacco products.

CONCLUSIONS

Among U.S. undergraduate and graduate students, there is a significant association between attention-deficit/hyperactivity disorder diagnosis and current use of E-cigarettes. Health consequences of E-cigarette use among individuals with an attention-deficit/hyperactivity disorder diagnosis warrant further investigation.

Smoking abstinence effects on emotion dysregulation in adult cigarette smokers with and without attention-deficit/hyperactivity disorder

BACKGROUND

Cigarette smoking is robustly associated with attention-deficit/hyperactivity disorder (ADHD), but little is known about psychological mechanisms accounting for this comorbid relationship. This study examined difficulties in emotion regulation, or emotion dysregulation, among adult cigarette smokers with and without ADHD. Emotion dysregulation was predicted to be higher in an ADHD group at screening and after 24 -h smoking abstinence compared to a non-ADHD group.

METHODS

Cigarette smokers with (n = 19) and without (n = 20) ADHD completed a screening visit, baseline visit, and two experimental visits: smoking as usual (i.e., smoking satiated) and after biochemically-verified 24 -h smoking abstinence (i.e., smoking abstinent). Three emotion dysregulation rating scales (two self-report and one clinician rated) were administered at the screening visit and experimental sessions. Experimental sessions also included two emotion dysregulation behavioral tasks.

RESULTS

The ADHD group scored higher on all three rating scales at screening (p's < .001). For experimental sessions, group (ADHD, non-ADHD) x condition (smoking satiated, smoking abstinence) interactions were not significant across measures. However, group main effects emerged indicating higher emotion dysregulation in the ADHD group across all measures (p's < .001). Main effects also emerged for experimental condition, but were more mixed across emotion dysregulation measures.

CONCLUSIONS

Emotion dysregulation was higher among adult smokers with ADHD and during smoking abstinence across diagnostic groups, suggesting that this malleable psychological mechanism plays a role in smoking both for those with and without ADHD-such findings can inform treatment and prevention efforts.

Probabilities of ADD/ADHD and Related Substance Use Among Canadian Adults

Objective: The aim of this study was to estimate the prevalence and probabilities of comorbidities between self-reported ADD/ADHD and smoking, alcohol binge drinking, and substance use disorders (SUDs) from a national Canadian sample. Method: Data were taken from the Public Use Microdata File of the 2012 Canadian Community Health Survey-Mental Health (N = 17 311). The prevalence of (a) smoking, (b) alcohol binge drinking, and (c) SUDs was estimated among those with an ADD/ADHD diagnosis versus those without an ADD/ADHD diagnosis. Results: After controlling for potential socioeconomic and mental health covariates, self-reported ADD/ADHD acted as a significant predictor for group membership in the heaviest smoking, heaviest drinking, and heaviest drug usage categories. Conclusion: Individuals self-reporting a diagnosis of ADD/ADHD were found to have a significantly higher likelihood of engaging in smoking and alcohol binge drinking, and were more likely to meet criteria for SUDs than individuals not reporting an ADD/ADHD diagnosis.

Dimensions of impulsive behavior: Predicting contingency management treatment outcomes for adolescent smokers

BACKGROUND

Behavioral measures of impulsive behavior include the dimensions of behavioral disinhibition, decision-making, and lapses of attention. These behaviors are associated with a range of risky activities during adolescence, including cigarette smoking; however, few studies have evaluated their associations with tobacco treatment outcomes. The current study examined the relationship between impulsive behavior and contingency management treatment outcomes for adolescent smokers.

METHODS

Data from two contingency management smoking cessation trials were combined (N = 189 adolescents). Participants provided breath carbon monoxide (CO) samples with incentives delivered contingent (i.e., active treatment [AT] condition) or non-contingent (i.e., control treatment [CT] condition) on CO level. Dimensions of impulsive behavior were assessed pre- and post-treatment using the Go/Stop Task, a measure of delay discounting, a continuous performance task, while self-reported impulsivity was assessed with the Barratt Impulsiveness Scale-Adolescent. Relationships between impulsive behavior and treatment outcomes (efficacy and adherence) were assessed using linear mixed effects models.

RESULTS

Participants in the AT condition had significantly lower program CO levels at each treatment phase. Delay discounting in the AT condition predicted CO levels, with those discounting the most lowering their breath CO levels the least. Delay discounting also predicted program adherence across both conditions.

CONCLUSIONS

Delay discounting may be the most relevant dimension of impulsive behavior to predict outcomes for adolescent smokers completing CM programs, both in terms of successful reductions in smoking and program adherence. Suggestions are made to reduce the effects of delay discounting for adolescent smokers using this treatment approach.

Attention-Deficit/Hyperactivity Disorder and Nicotine Dependence in Adults

Introduction

The aim of this study is to assess clinical characteristics and smoking profiles of individuals diagnosed with attention-deficit/hyperactivity disorder (ADHD) and compare their nicotine dependence status with healthy controls for better understanding the mutual and complex relationship between ADHD and smoking.

Methods

We included the following participants in the study: 40 adults with the diagnosis of ADHD, 40 participants who visited the smoking cessation polyclinic without any psychiatric disorders, and 40 healthy controls. A sociodemographic data form, Wender Utah Rating Scale (WURS), Adult ADD/ADHD Diagnosis and Evaluation Inventory, and Fagerstrom Nicotine Dependence Test (FNDT) were administered to the participants.

Results

Mean age of the ADHD, nicotine dependence, and control groups was 28.68±7.22, 34.17±8.60, 33.70±7.45 years, respectively. Percentages of females and males were 27.5% and 72.5% in the ADHD group, 50% and 50% in the nicotine dependence group, 47.5% and 52.5% in the control group. The attention-deficit scores in the ADHD, nicotine dependence, and control groups were 21.18±5.05, 7.23±3.96, 4.75±2.65, respectively (p=0.001), whereas the hyperactivity scores were.73±5.84, 6.43±4.2, and 3.58±2.27, respectively (p=0.001). The related features scores were 56.53±12.96, 24.30±13.93, and 13.13±6.11, respectively (p=0.001), whereas the WURS scores were 61.88±12.69, 23.03±16.07, 11.90±8.15, respectively (p=0.001). FNDT scores in ADHD and nicotine dependence groups were 5.83±2.11 and 6.20±2.74, respectively (p=0.495).

Conclusion

Considering the argument of ADHD being an independent risk factor for nicotine dependence, we think the co-occurrence of the smoking addiction and ADHD symptoms in the context of dopamine dysregulation is important in the clinical setting. Treatment modalities and of preventive strategies should be considered while keeping this in mind.

ADHD symptoms impact smoking outcomes and withdrawal in response to Varenicline treatment for smoking cessation

INTRODUCTION

Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with nicotine dependence and difficulty quitting smoking. Few cessation trials specifically consider the impact of ADHD on treatment outcomes, including those testing established pharmacological therapies, such as varenicline.

METHODS

The current study focused on the impact of pretreatment ADHD inattention (IN) and hyperactivity-impulsivity (HI) symptoms on treatment outcome in a randomized controlled trial of varenicline [N=205, average age=34.13(10.07), average baseline cigarettes per day=14.71(7.06)]. Given that varenicline's putative therapeutic mechanism is attenuation of withdrawal severity during abstinence, we also tested changes in withdrawal as a mediator of treatment effects in high and low ADHD groups.

RESULTS

ADHD symptom severity in this sample was in the subclinical range. Cessation was associated with HI, but not IN, such that high HI individuals on varenicline reported the lowest smoking levels at the end of treatment across all groups (3.06cig/day for high HI vs 4.02cig/day for low HI). Individuals with high HI who received placebo had the highest smoking at the end of treatment (7.69cigs/day for high HI vs 5.56cig/day for low HI). Patterns continued at follow-up. Varenicline significantly reduced withdrawal for those with high HI, but not low HI. However, path models did not support an indirect effect of medication on reducing smoking via withdrawal in either group, suggesting that unmeasured variables are involved in varenicline's effect on reducing smoking.

CONCLUSIONS

These data add to a gap in the smoking cessation literature regarding the impact of ADHD symptoms on the efficacy and mechanisms of frontline pharmacological treatments.

Adult attention-deficit/hyperactivity disorder and nicotine withdrawal: a qualitative study of patient perceptions

BACKGROUND

Nicotine use has been reported to ameliorate symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). Furthermore, adults with ADHD have a relatively high prevalence of cigarette smoking and greater difficulty abstaining from smoking. Overall, though, there is scant literature investigating the beliefs, perceptions and experiences of smokers with ADHD regarding smoking cessation and withdrawal.

METHODS

Our participants (n = 20) fulfilling criteria for ADHD and a past or current dependence from nicotine were recruited from the in- and outpatient clinic of the Zurich University Psychiatric Hospital and the Psychiatric Services Aargau (Switzerland). We conducted in-depth interviews to explore their motivations to quit, past experiences with and expectations about quitting using a purposeful sampling plan. The sample was selected to provide diversity in relation to level of nicotine dependence, participation in a smoking-cessation program, gender, age, martial status and social class. Mayring's qualitative content analysis approach was used to evaluate findings.

RESULTS

Adult smokers with ADHD had made several attempts to quit, experienced intense withdrawal symptoms, and relapsed early and often. They also often perceived a worsening of ADHD symptoms with nicotine abstinence. We identified three motives to quit smoking: 1) health concerns, 2) the feeling of being addicted, and 3) social factors. Most participants favored a smoking cessation program specifically designed for individuals with ADHD because they thought ADHD complicated their nicotine withdrawal and that an ADHD-specific smoking cessation program should address specific symptoms of this disorder.

CONCLUSIONS

Since treatment initiation and adherence associate closely with perception, we hope these findings will result in better cessation interventions for the vulnerable subgroup of smokers with ADHD.

ADHD and Suicidal Ideation: The Roles of Emotion Regulation and Depressive Symptoms Among College Students

OBJECTIVE

ADHD appears to increase risk for both depression and suicidal ideation, while ADHD and depression are also associated with emotion regulation deficits. Thus, we evaluated the degree to which depression mediated the association between ADHD and suicidal ideation, as well as the degree to which emotion regulation deficits moderated the association ADHD shared with depression and suicidal ideation in a nonclinical sample.

METHOD

Participants were undergraduate psychology students (N = 627; age: M = 20.23, SD = 1.40; 60% female; 47% European American) who completed an online assessment.

RESULTS

Results indicated that ADHD indirectly increased suicidal ideation through depression. Emotion regulation deficits of accepting negative emotions, emotional awareness, and goal-oriented behavior moderated the indirect effect of ADHD on suicidal ideation.

CONCLUSION

Depression appears to play an important mediating role in suicidal ideation for college students with ADHD, and specific emotion regulation deficits appear to amplify the effects of ADHD on depression and suicidal ideation.

Anxiety and Depressed Mood Decline Following Smoking Abstinence in Adult Smokers with Attention Deficit Hyperactivity Disorder

INTRODUCTION

A preponderance of relevant research has indicated reduction in anxiety and depressive symptoms following smoking abstinence. This secondary analysis investigated whether the phenomenon extends to smokers with attention deficit hyperactivity disorder (ADHD).

METHODS

The study setting was an 11-Week double-blind placebo-controlled randomized trial of osmotic release oral system methylphenidate (OROS-MPH) as a cessation aid when added to nicotine patch and counseling. Participants were 255 adult smokers with ADHD. The study outcomes are: anxiety (Beck Anxiety Inventory (BAI)) and depressed mood (Beck Depression Inventory II (BDI)) measured one Week and six Weeks after a target quit day (TQD). The main predictor is point-prevalence abstinence measured at Weeks 1 and 6 after TQD. Covariates are treatment (OROS-MPH vs placebo), past major depression, past anxiety disorder, number of cigarettes smoked daily, demographics (age, gender, education, marital status) and baseline scores on the BAI, BDI, and the DSM-IV ADHD Rating Scale.

RESULTS

Abstinence was significantly associated with lower anxiety ratings throughout the post-quit period (p<0.001). Depressed mood was lower for abstainers than non-abstainers at Week 1 (p<0.05), but no longer at Week 6 (p=0.83). Treatment with OROS-MPH relative to placebo showed significant reductions at Week 6 after TQD for both anxiety (p<0.05) and depressed mood (p<0.001), but not at Week 1. Differential abstinence effects of gender were observed. Anxiety and depression ratings at baseline predicted increased ratings of corresponding measures during the post-quit period.

CONCLUSION

Stopping smoking yielded reductions in anxiety and depressed mood in smokers with ADHD treated with nicotine patch and counseling. Treatment with OROS-MPH yielded mood reductions in delayed manner.

Prevalence and smoking behavior characteristics of nonselected smokers with childhood and/or adult self-reported ADHD symptoms in a smoking-cessation program: a cross-sectional study

BACKGROUND

ADHD involves impairing core symptoms of inattention and hyperactivity/impulsivity in children (childhood ADHD = CH) that may persist in adulthood (adult ADHD = AD). Conflicting findings have been found regarding AD prevalences among adult smokers, and it is unclear whether AD is associated with a more severe smoking behavior in adulthood.

OBJECTIVE

The aim of this article is (a) to determine CH and AD prevalences in a nonselected sample of adult smokers, (b) to describe the characteristics of smokers with ADHD symptoms versus those without, and (c) to determine whether CH and/or AD symptoms are risk factors for more severe smoking in adulthood.

METHOD

Three hundred and seventy-three participants aged 18 years and over were prospectively recruited in a smoking-cessation unit. Participants were classified as "no ADHD symptoms," "CH symptoms," or "AD symptoms" according to their baseline score on the Wender Utah Rating Scale (WURS) alone (for CH symptoms) and WURS combined to the Adult Self Report Scale (ASRS) for AD symptoms. Other clinical variables were reported at first consultation.

RESULTS

(a) CH symptoms were reported in 15.3% (57/373) of the total sample, 42.1% (24/57) of whom also had persistent ADHD symptoms in adulthood (prevalence of AD was 24/373 = 6.4%). (b) In comparison with participants without ADHD symptoms, smokers with ADHD symptoms consume significantly more tobacco, but ADHD symptoms were no longer significantly associated with the daily number of smoked cigarettes after adjustment for sociodemographic variables. No significant association was found between the two groups and age at the first cigarette, age at onset daily smoking, and nicotine dependence. (c) Participants were categorized into three groups: Group 1 without ADHD symptoms lifetime (NH; n = 316), Group 2 with childhood history of ADHD symptoms (CH; n = 33), and Group 3 with Adult ADHD symptoms (AD; n = 24). The association with tobacco consumption (>20 cigarettes/day) was significant for CH only (p = .02). After adjustment for gender, age, professional status, and educational level, this association was not longer significant.

CONCLUSION

Childhood and adult ADHD symptoms are both highly prevalent among nonselected smokers but our study failed to show more severe smoking characteristics among these participants after adjustment with sociodemographic variables.

Ecological momentary assessment of antecedents and consequences of smoking in adults with attention-deficit/hyperactivity disorder

The current study assessed antecedents and consequences of ad lib cigarette smoking in smokers diagnosed with attention-deficit/hyperactivity disorder (ADHD) using ecological momentary assessment (EMA). Adult smokers with ADHD (n = 17) completed 870 smoking and 622 nonsmoking electronic diary entries over a 7-day observation period of their naturalistic smoking behavior. Data collection occurred from 2011 to 2012. Generalized estimating equations indicated that ADHD smokers were more likely to smoke when urge to smoke, negative affect, boredom, stress, worry, and restlessness were elevated. In addition, participants were more likely to smoke in situations that elicited higher levels of nervousness and frustration. ADHD symptoms, in general, did not differ between smoking and nonsmoking contexts, though hyperactive-impulsive ADHD symptoms were elevated prior to smoking in frustrating situations. Additional situational antecedent variables were associated with smoking, including being in the presence of others smoking, being in a bar or restaurant, while outside, and while consuming caffeinated or alcoholic beverages. Participants also reported a significant improvement in urge to smoke, negative affect, stress, hunger, and ADHD symptoms after smoking a cigarette. Findings suggest certain contextual factors that may maintain ad lib cigarette smoking in smokers with ADHD and identify potential treatment targets in smoking cessation interventions for this at-risk group. Clinical implications and future research directions are discussed. Funding for this study was provided by the National Institute on Drug Abuse.

ADHD, altered dopamine neurotransmission, and disrupted reinforcement processes: implications for smoking and nicotine dependence

Attention deficit hyperactivity disorder (ADHD) is a common and impairing disorder affecting millions of children, adolescents, and adults. Individuals with ADHD smoke cigarettes at rates significantly higher than their non-diagnosed peers and the disorder also confers risk for a number of related adverse smoking outcomes including earlier age of initiation, faster progression to regular use, heavier smoking/greater dependence, and more difficulty quitting. Progress in our understanding of dopamine neurotransmission and basic behavioral reinforcement processes in ADHD may help increase our understanding of the ADHD-smoking comorbidity. This review will examine how these areas have been studied and how further work may aid in the development of better prevention and treatment for smoking in those with ADHD.

Associations of attention-deficit hyperactivity disorder symptom dimensions with smoking deprivation effects in adult smokers

Identifying relations of attention deficit hyperactivity disorder (ADHD) symptom dimensions to individual facets of the tobacco withdrawal syndrome could elucidate the mechanisms linking ADHD and regular smoking. This study examined the unique relations of inattention (IN) and hyperactivity-impulsivity (HI) symptom dimensions of ADHD to a variety of tobacco withdrawal symptoms. One hundred thirty-two community-dwelling adult smokers recruited without regard to ADHD status completed a self-report measure of ADHD symptoms experienced over the past 6 months at a baseline visit. At two subsequent experimental sessions (one following overnight tobacco deprivation and one nondeprived; order counterbalanced), participants completed measures of tobacco withdrawal symptoms, mood, and desire to smoke. Preliminary analyses showed that higher levels of IN and HI symptoms were both associated with higher levels of negative affect and concentration difficulties during nondeprived ("baseline") states (ps < .01). Over and above nondeprived ratings, higher levels of HI symptoms were associated with larger deprivation-induced increases in negative affect, concentration problems, and desire to smoke, particularly for negative affect relief, during deprived states (ps < .01). ADHD symptoms, particularly HI symptoms, are associated with more severe exacerbations in abstinence-induced withdrawal symptoms, which could be an important mechanism of ADHD-smoking comorbidity. These findings suggest the need for clinical studies examining the role of these unique and potentially more severe withdrawal profiles experienced by smokers with high-levels of ADHD symptoms in smoking reinstatement and cessation outcomes.

A pilot study of lis-dexamfetamine dimesylate (LDX/SPD489) to facilitate smoking cessation in nicotine-dependent adults with ADHD

OBJECTIVE

The goal of this study was to assess the efficacy and tolerability of lis-dexamfetamine dimesylate (LDX) as an adjunct to nicotine replacement therapy in adult smokers with ADHD who were undergoing a quit attempt.

METHODS

Thirty-two regular adult smokers with ADHD were randomized to receive LDX (n = 17) or placebo (n = 15) in addition to nicotine patch concurrent with a quit attempt.

RESULTS

There were no differences between smokers assigned to LDX versus placebo in any smoking outcomes. Participants treated with LDX demonstrated significant reductions in self-reported and clinician-rated ADHD symptoms. LDX was well tolerated in smokers attempting to quit.

DISCUSSION

In general, LDX does not facilitate smoking cessation in adults with ADHD more than does placebo, though both groups significantly reduced smoking. LDX demonstrated efficacy for reducing ADHD symptoms in adult smokers engaging in a quit attempt.

Smoking behavior characteristics of non-selected smokers with childhood attention-deficit/hyperactivity disorder (AD/HD) history: a systematic review and meta-analysis

It is unclear whether adult smokers with childhood attention-deficit/hyperactivity disorder history (CH) have more severe smoking behavior than non-CH smokers, while it is clearly suggested that CH adolescents have more severe smoking behavior than CH adolescents. The aim of the present comprehensive meta-analysis is to determine whether CH smokers have more severe smoking behavior characteristics than those without and the effect of age on the association between CH and smoking behavior. We included all case-control studies and first round data collection of observational studies addressing the difference in smoking behavior characteristics of CH smokers versus non-CH smokers, with validated scales or structured interviews, without any language or date restriction. Nine studies (including 365 smokers with CH and 1,708 smokers without) were included. Compared to non-CH smokers, CH smokers smoked significantly more cigarettes [standardized mean differences (SMD) = 0.15, 95 % CI 0.01-0.28, p = 0.04] and began to regularly smoke earlier (SMD = -0.28, 95 % CI -0.49; -0.07, p = 0.01) but were not significantly more nicotine dependent (SMD = 0.23, 95 % CI -0.04 to 0.48, p = 0.08). After removing the single adolescent study, the significant association between CH and number of daily smoked cigarettes disappeared, and subgroups analyses confirmed that the significant association between CH and number of daily smoked cigarettes disappeared as age increased. Our meta-analysis illustrates a clinically important link between CH and tobacco smoking in adolescence but not later in life. Further high-quality studies are needed to confirm this finding, as only two studies included participants with a mean age below 20 years.

Prefrontal hemodynamic changes during cigarette smoking in young adult smokers with and without ADHD

Individuals with attention-deficit/hyperactivity disorder (ADHD) have elevated smoking prevalence and reduced cessation rates compared to the general population. However, the effects of cigarette smoking on underlying brain activity in smokers with ADHD are not well characterized. Non-invasive near-infrared spectroscopy (NIRS) was used to characterize how cigarette smoking affects prefrontal brain hemodynamics in smokers with and without ADHD. Prefrontal changes of oxy- and deoxyhemoglobin (HbO2 and HHb) were measured in six male adult smokers with ADHD and six age- and gender-matched control smokers. NIRS measurements were separated into four sequential time intervals, i.e., before smoking, during smoking, after smoking, and during a breath hold. Prefrontal HbO2 was lower during smoking in smokers with ADHD compared to control smokers. More specifically, smokers with ADHD showed decreased prefrontal HbO2 during smoking compared to breath hold, before and after smoking periods. In contrast, control smokers showed increased prefrontal HbO2 from before smoking to breath hold. Decreased prefrontal HbO2 in smokers with ADHD may reflect a smoking-induced change in prefrontal brain activity and microvasculature, which is not found in smokers without ADHD. The lower prefrontal HbO2 may be a biomarker for increased susceptibility to tobacco smoke in smokers with ADHD. Smoking in individuals with ADHD may increase vasoconstriction of cerebral arteries in the prefrontal cortex, which may contribute to a reduction in HbO2. The findings highlight the importance of smoking cessation, in particular in those smokers who use nicotine to self-medicate ADHD symptoms.

Methylphenidate does not influence smoking-reinforced responding or attentional performance in adult smokers with and without attention deficit hyperactivity disorder (ADHD)

Individuals with Attention Deficit Hyperactivity Disorder (ADHD) smoke cigarettes at rates higher than the general population and questions have been raised about how stimulant drugs-the frontline pharmacological treatment for ADHD-influence smoking risk and behavior in those with ADHD. In the present study adult regular smokers with (n = 16) and without (n = 17) ADHD participated in 3 experimental sessions in which they completed a Progressive Ratio (PR) task to measure the relative reinforcing effects of cigarette smoking and money after oral administration of placebo and 2 active doses of methylphenidate (10 mg and 40 mg). We also measured attention and inhibitory control via a Continuous Performance Test (CPT). Methylphenidate had no effect on smoking-reinforced responding, attention, or inhibitory control in either group. Attention and inhibitory control were associated with smoking-reinforced responding, but unsystematically and only in the non-ADHD group. Several design features, such as the value of the monetary response option, the PR schedule, and the potential effects of smoking on attention and inhibitory control, could have contributed to the negative findings and are discussed as such. Although inconsistent with some previous human laboratory studies of stimulant drugs and smoking, results are consistent with recent trials of stimulant drugs as adjuncts for smoking cessation in adult smokers with ADHD. In general, methylphenidate at mild and moderate doses did not influence the relative reinforcing effects of cigarette smoking in adults with and without ADHD.

The effects of acute nicotine, chronic nicotine, and withdrawal from chronic nicotine on performance of a cued appetitive response

Nicotine is a widely used addictive drug, with an estimated 73 million Americans 12 years of age or older having used a tobacco product in the last month, despite documented risks to personal health. Nicotine alters cognitive processes, which include effects on attention and impulsivity, a mechanism that may contribute to the addictive properties of the drug. Individuals with a variety of psychological disorders ranging from attention deficit hyperactivity disorder (ADHD) to schizophrenia smoke at a higher rate than the rest of the population and show deficits in impulse control. The present studies evaluated the effects of acute, chronic, and withdrawal from chronic nicotine on an operant task that measured premature and signaled nose pokes, as well as performance efficiency in C57BL/6J mice. Results indicate that acute nicotine (0.09 mg/kg intraperitoneally) does not alter the acquisition of the task, but does significantly increase performance efficiency once the behavior has been learned. In contrast, chronic nicotine (0, 6.3, 12.6, and 36 mg/kg/day subcutaneously) and withdrawal from chronic nicotine had no effect on performance efficiency. These results suggest that initial nicotine use may have beneficial effects on inhibitory control, but these effects are not maintained with chronic nicotine consumption as tolerance develops. The findings may provide an explanation for higher rates of smoking in patients with impulse control issues, as the smoking may represent an initial attempt at self-medication.

Treating nicotine dependence by targeting attention-deficit/ hyperactivity disorder (ADHD) with OROS methylphenidate: the role of baseline ADHD severity and treatment response

OBJECTIVE

To determine whether treatment of attention-deficit/hyperactivity disorder (ADHD) with osmotic-release oral system (OROS) methylphenidate promotes abstinence from smoking among smokers with ADHD who have greater severity of ADHD symptoms at baseline or greater improvement in ADHD during treatment.

METHOD

This is a secondary analysis of data from a randomized, double-blind, 11-week trial conducted between December 2005 and January 2008 at 6 clinical sites; the original trial was sponsored by the National Drug Abuse Clinical Trials Network. Adult cigarette smokers (aged 18-55 years) who met DSM-IV criteria for ADHD were randomly assigned to OROS methylphenidate (72 mg/d) (n = 127) or matching placebo (n = 128). All participants received nicotine patches (21 mg/d) and weekly individual smoking cessation counseling. Logistic regression was used to model prolonged abstinence from smoking (ascertained by self-report and breath carbon monoxide testing) as a function of treatment, baseline ADHD Rating Scale-IV (ADHD-RS) score, change in ADHD-RS score during treatment, and their interactions.

RESULTS

Treatment interacted with both ADHD-RS score at baseline (P = .01) and change in ADHD-RS score during treatment (P = .008). Among patients with higher ADHD-RS scores (> 36) at baseline and the most improvement in ADHD during treatment (ADHD-RS change score ≥ 24), 70.0% of those who took OROS methylphenidate achieved abstinence from smoking compared to 36.8% of those who took placebo (P = .02). In contrast, among patients with the lowest ADHD-RS baseline scores (≤ 30), 30.3% of those who took OROS methylphenidate achieved abstinence from smoking compared to 60.7% of those who took placebo (P = .02).

CONCLUSIONS

OROS methylphenidate, in combination with nicotine patch, may be an effective treatment for nicotine dependence among smokers with more severe ADHD and more robust response of ADHD symptoms to medication. OROS methylphenidate may be counterproductive among smokers with lower severity of ADHD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00253747.

Self-reported major depressive symptoms at baseline impact abstinence prognosis in smoking cessation program. A one-year prospective study

OBJECTIVE

The association between major depressive symptoms and smoking has been extensively documented. However, previous studies report conflicting findings about the impact of depression on lapse of smoking cessation. We hypothesize that smokers with self-reported major depressive symptoms at baseline are at higher risk of a lapse.

METHODS

One thousand and twenty participants aged, 18 years and over, were recruited in a smoking-cessation unit. All participants were assessed for their smoking status six times during one year of follow-up. Participants were classified as "euthymic", presenting "minor depressive symptomatology" or "major depressive symptomatology" according to their baseline score on the Hospitalization Anxiety and Depression Scale.

RESULTS

Using Cox's proportional hazard regression modeling, adjusted for potential confounding factors (nicotine dependence, number of cigarettes/day, previous cessation attempt, alcohol misuse, socio-demographic variables), it was shown that lapse is associated with major depressive symptoms (Hazard Ratio: HR=1.23 [1.02;1.47]; p=0.03).

CONCLUSION

Our results suggest the importance for clinicians to deal with depression and to discriminate minor from major depressive symptoms at preliminary smoking cessation consultations.

Symptom dimensions of attention deficit hyperactivity disorder and nicotine withdrawal symptoms

Research suggests that Attention Deficit Hyperactivity Disorder (ADHD) and nicotine withdrawal symptoms are related; however, it is unknown how this relationship extends across ADHD symptom gradations, differs between inattention and hyperactivity-impulsivity symptom types, and generalizes to a national sample. This study examined cross-sectional associations between childhood ADHD symptom indexes (total, inattention, and hyperactivity-impulsivity) and lifetime DSM-IV nicotine withdrawal symptoms. Results showed that each ADHD symptom index associated with almost every withdrawal symptom (Ps < .01). After controlling for hyperactivity-impulsivity and inattention symptom overlap, inattention (but not hyperactivity-impulsivity) retained incremental associations with most withdrawal symptoms. These findings are relevant for understanding mechanisms of ADHD and smoking comorbidity.

Effects of smoking abstinence on smoking-reinforced responding, withdrawal, and cognition in adults with and without attention deficit hyperactivity disorder

RATIONALE

Individuals with attention deficit hyperactivity disorder (ADHD) have a more difficult time quitting smoking compared to their non-ADHD peers. Little is known about the underlying behavioral mechanisms associated with this increased risk.

OBJECTIVES

This study aims to assess the effects of 24-h smoking abstinence in adult smokers with and without ADHD on the following outcomes: smoking-reinforced responding, withdrawal, and cognitive function.

METHODS

Thirty-three (n = 16 with ADHD, 17 without ADHD) adult smokers (more than or equal to ten cigarettes/day) were enrolled. Each participant completed two experimental sessions: one following smoking as usual and one following biochemically verified 24-h smoking abstinence. Smoking-reinforced responding measured via a progressive ratio task, smoking withdrawal measured via questionnaire, and cognition measured via a continuous performance test (CPT) were assessed at each session.

RESULTS

Smoking abstinence robustly increased responding for cigarette puffs in both groups, and ADHD smokers responded more for puffs regardless of condition. Males in both groups worked more for cigarette puffs and made more commission errors on the CPT than females, regardless of condition. Smoking abstinence also increased ratings of withdrawal symptoms in both groups and smokers with ADHD, regardless of condition, reported greater symptoms of arousal, habit withdrawal, and somatic complaints. Across groups, smoking abstinence decreased inhibitory control and increased reaction time variability on the CPT. Abstinence-induced changes in inhibitory control and negative affect significantly predicted smoking-reinforced responding across groups.

CONCLUSIONS

Smokers with ADHD reported higher levels of withdrawal symptoms and worked more for cigarette puffs, regardless of condition, which could help explain higher levels of nicotine dependence and poorer cessation outcomes in this population. Abstinence-induced changes in smoking-reinforced responding are associated with changes in inhibitory control and negative affect regardless of ADHD status, a finding that may lead to novel prevention and treatment programs.

Cognitive function during nicotine withdrawal: Implications for nicotine dependence treatment

Nicotine withdrawal is associated with deficits in neurocognitive function including sustained attention, working memory, and response inhibition. Several convergent lines of evidence suggest that these deficits may represent a core dependence phenotype and a target for treatment development efforts. A better understanding of the mechanisms underlying withdrawal-related cognitive deficits may lead to improve nicotine dependence treatment. We begin with an overview of the neurocognitive effects of withdrawal in rodent and human models, followed by discussion of the neurobehavioral mechanisms that are thought to underlie these effects. We then review individual differences in withdrawal-related neurocognitive effects including genetics, gender, and psychiatric comorbidity. We conclude with a discussion of the implications of this research for developing improved therapies, both pharmacotherapy and behavioral treatments, that target cognitive symptoms of nicotine withdrawal. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.

ADHD as a serious risk factor for early smoking and nicotine dependence in adulthood

OBJECTIVE

Tobacco smoking and ADHD frequently co-occur. So far, the bulk of research on the ADHD-smoking comorbidity has been done in children with ADHD and nonclinical adult samples. To assess smoking habits in adults with ADHD, the authors used the Fagerström test for nicotine dependence (FTND).

METHOD

In 60 adult outpatients, with an ADHD diagnosis according to Diagnostic and statistical manual of mental disorders (4th ed.; DSM-IV) criteria and 60 age- and gender-matched controls, smoking habits were assessed with the FTND.

RESULTS

The authors replicated earlier findings in children confirming a higher rate of smokers in the ADHD group. The adult smokers with ADHD suffered from more severe nicotine dependence and smoked significantly more often when being sick. Females with ADHD smoked significantly more often and started smoking at an earlier age.

CONCLUSION

Applying the FTND, the authors confirmed a high rate of highly dependent smokers among adult ADHD patients. The authors' findings point to a higher vulnerability for the development of nicotine dependence in women with ADHD.

Separate and overlapping relationships of inattention and hyperactivity/impulsivity in children and adolescents with attention-deficit/hyperactivity disorder

There is debate regarding the dimensional versus categorical nature of attention-deficit/hyperactivity disorder (ADHD). This study utilized confirmatory factor analysis to examine this issue. ADHD symptoms rated on interviews and rating scales from a large sample of individuals (ages 3-17, 74 % male, 75 % Caucasian) with ADHD were examined (n = 242). Four potential factor structures were tested to replicate prior findings in a sample with a wide age range and included only participants who met DSM-IV-TR diagnostic criteria for ADHD. Correlations with executive function measures were performed to further assess the separability and validity of the derived factors. The data support a bifactor model with a general ADHD factor and two specific factors, inattention and hyperactivity/impulsivity. Importantly, the individual factors were also differentially correlated with executive functioning measures. This study adds to a growing literature suggesting both a general component to ADHD, as well as dimensional traits of inattention and hyperactivity/impulsivity, associated with distinct executive functioning profiles. The presence of a general underlying factor contraindicates separating the inattentive and combined subtypes of ADHD into distinct disorders.

Osmotic release oral system methylphenidate prevents weight gain during a smoking-cessation attempt in adults with ADHD

BACKGROUND

Adults with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for both cigarette smoking and being overweight or obese. Although smoking cessation tends to result in weight increase, potentially initiating or exacerbating weight problems, adults with ADHD who are treated with osmotic release oral system methylphenidate (OROS-MPH) tend to lose weight. It is unclear how the use of OROS-MPH during a smoking-cessation attempt might affect the typical weight gain that accompanies cessation.

METHOD

We examined changes in weight and hunger during a smoking-cessation attempt in 215 adults with ADHD who completed a multisite, randomized, controlled trial and were randomized to either OROS-MPH (n = 107) or placebo (n = 108) (NCT #00253747). Both groups also received open-label transdermal nicotine replacement and counseling.

RESULTS

Participants who received OROS-MPH lost an average of 1.6% of their body weight during the 11-week study, whereas those who received placebo gained an average of 1.3% of their weight (p < .001). Hunger ratings were lower in the OROS-MPH group (M = 1.1, SD = 0.8) than in the placebo group (M = 1.6, SD = 0.9; p < .001).

CONCLUSIONS

The use of OROS-MPH during a smoking-cessation attempt prevents weight gain in adults with ADHD who substantially reduce or quit smoking. The potential utility of OROS-MPH in individuals with ADHD who are attempting to quit smoking and for whom weight gain would be problematic warrants further research.

Preliminary evidence that adherence to counseling mediates the effects of pretreatment self-efficacy and motivation on outcome of a cessation attempt in smokers with ADHD

BACKGROUND

Few studies have evaluated predictors of smoking cessation outcomes in smokers with attention-deficit/hyperactivity disorder (ADHD), which could help to improve suboptimal treatment outcomes in this population. The purpose of this study was to examine pretreatment thoughts about smoking abstinence (i.e., desire to quit, perceived difficulty quitting, and expected success in quitting) as predictors of smoking cessation outcomes in smokers with ADHD and to determine the extent to which treatment adherence mediates these relationships.

METHODS

Participants were adult smokers with ADHD (n = 255), who were enrolled in a multisite smoking cessation study and received either osmotic-release oral system methylphenidate (OROS-MPH) or placebo in combination with transdermal nicotine replacement and brief cessation counseling. Bootstrapped logistic regression models were generated to test main effects of thoughts about abstinence on smoking cessation outcomes and to examine treatment adherence as a mediator of these relationships.

RESULTS

Desire to quit and expected success in quitting, but not perceived difficulty quitting, predicted smoking cessation outcomes, as did all of the treatment adherence variables (i.e., percent sessions attended, counselor ratings of counseling adherence, and percent patch adherence). Counseling adherence partially mediated the relationship between smoking cessation outcomes and both pretreatment desire to quit and expected success.

CONCLUSIONS

Smokers with ADHD who have higher self-efficacy (i.e., expected success) and motivation (i.e., desire) to quit are more adherent to smoking cessation counseling and have better smoking cessation outcomes. Additional research is needed to determine whether treatment-seeking smokers with ADHD would benefit from an intervention designed to increase self-efficacy and motivation to quit.

Attention-deficit/hyperactivity disorder (ADHD) symptoms, craving to smoke, and tobacco withdrawal symptoms in adult smokers with ADHD

BACKGROUND

Tobacco withdrawal symptoms may be confounded with attention-deficit/hyperactivity disorder (ADHD) symptoms among smokers with ADHD.

OBJECTIVE

(1) To assess overlap between ADHD symptoms and tobacco/nicotine withdrawal symptoms and craving; (2) to assess the relationship between craving or withdrawal symptoms and the effect of osmotic-release oral system methylphenidate (OROS-MPH) on ADHD symptoms; (3) to assess the association of ADHD symptoms, craving, and withdrawal symptoms with abstinence.

METHODS

Secondary analysis of a randomized, placebo controlled smoking cessation trial assessing the efficacy of OROS-MPH taken in addition to nicotine patch among individuals with ADHD. ADHD symptoms, withdrawal symptoms, and craving were assessed at baseline and 2, 4 and 6 weeks after a target quit day.

RESULTS

Withdrawal symptoms and craving showed limited and modest overlap with ADHD symptoms prior to abstinence but more extensive and stronger correlation after quit day. Compared to placebo, OROS-MPH reduced ADHD symptoms; this effect was attenuated by controlling for withdrawal symptoms, but not by craving. Craving, but not ADHD symptoms and withdrawal symptoms, was associated with abstinence during the trial.

CONCLUSION

When treating smokers with ADHD (1) craving, rather than tobacco withdrawal symptoms or ADHD symptoms may be the more effective therapeutic smoking cessation targets; (2) careful distinction of craving, withdrawal symptoms, and ADHD symptoms when assessing withdrawal phenomena is needed.

A systematic review of global publication trends regarding long-term outcomes of ADHD

There is increased global recognition of attention deficit hyperactivity disorder (ADHD) as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs) in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least 2 years in duration were examined. A total of 351 studies were identified in the final analysis. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of 42 publications in 2008. This rise in publications on ADHD LTOs may reflect a rise in global interest and recognition of consequences and impairment associated with ADHD. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Geographical differences in the focus of ADHD LTO studies may reflect regional variations in cultural values. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. These changes in basic study design may reflect an increase in the recognition that ADHD is a lifetime chronic disorder. This systematic review analysis of publication trends in ADHD LTOs reflects geographically based interests that change over time.

Assessing the role of attention-deficit/hyperactivity disorder symptoms in smokers with and without posttraumatic stress disorder

INTRODUCTION

Smoking prevalence among individuals with posttraumatic stress disorder (PTSD) is elevated relative to non-PTSD smokers, and there is evidence to suggest that affect regulation may be a motivation for smoking among those with this disorder. Previous studies have also indicated that (a) PTSD is frequently comorbid with attention-deficit/hyperactivity disorder (ADHD), (b) individuals with ADHD smoke at significantly higher rates than the general population, (c) subclinical ADHD symptoms are a risk factor for smoking, and (d) affect regulation is a motivation for smoking in ADHD. The goal of this study was to assess the degree to which ADHD symptoms were uniquely associated with smoking-related affective functioning (SRAF) variables above and beyond the variance already explained by PTSD symptoms.

METHODS

Smokers with (n = 55) and without PTSD (n = 68) completed measures assessing PTSD symptoms, ADHD symptoms, and SRAF.

RESULTS

The PTSD group endorsed significantly more severe levels of DSM-IV inattentive and hyperactive-impulsive ADHD symptoms. A series of hierarchical regressions among the entire sample indicated that, after accounting for PTSD symptoms, ADHD symptoms were associated with lower positive affect, higher negative affect, higher emotion dysregulation, higher anxiety sensitivity, and higher urges to smoke to increase positive affect.

CONCLUSIONS

Taken together, these findings suggest that ADHD symptoms may increase affective dysregulation difficulties already faced by smokers, particularly those with PTSD, which may, in turn, confer increased risk for smoking relapse in those with higher levels of symptomatology of both disorders.

Attention-deficit/hyperactivity disorder subtypes in adolescents with comorbid substance-use disorder

BACKGROUND

Little is known about the relationship between attention-deficit/hyperactivity disorder (ADHD) subtypes and substance-use disorder (SUD). As there is literature suggesting different subtype phenotypes, there may be subtype differences in regard to the risk for developing SUD and substance treatment response.

OBJECTIVES

To characterize the sample in a Clinical Trials Network (CTN) study according to ADHD subtypes and baseline psychosocial and substance-use characteristics and to compare subtypes on response to treatment.

METHODS

Secondary analyses on data collected from adolescents (n = 276) diagnosed with ADHD and SUD (non-nicotine) and treated with stimulant medication or placebo and cognitive behavioral therapy (CBT) for substance use. Participants were characterized as inattentive or combined ADHD subtype and compared on baseline characteristics and treatment outcome.

RESULTS

The combined subtype presented with more severe SUDs and higher rates of conduct disorder. There were a greater proportion of boys with inattentive subtype. The inattentive subtype appeared less ready for treatment (greater University of Rhode Island Change Assessment precontemplation scores) with poorer coping skills (poorer problem-solving and abstinence focused coping) at baseline. However, the two subtypes responded equally to treatment even after controlling for baseline differences.

CONCLUSIONS

Findings from this large community sample indicate that there were no subtype differences in treatment response, although there were differences in terms of substance use, antisocial behavior, readiness for treatment, and gender prior to treatment.

SCIENTIFIC SIGNIFICANCE

This study is the first to report on subtype differences for treatment response for non-nicotine SUD in a comorbid ADHD-SUD population. Despite some baseline differences, both subtypes responded equally to treatment, suggesting limited relevance for subtype designation on treatment planning.

Divergence by ADHD subtype in smoking cessation response to OROS-methylphenidate

INTRODUCTION

Attention deficit hyperactivity disorder (ADHD) is a neuropsychiatric condition subclassified in DSM-IV according to its core symptoms domains as (a) predominantly inattentive (ADHD-IN), (b) predominantly hyperactive/impulsive (ADHD-H), and (c) combined inattentive and hyperactive/impulsive (ADHD-C). Whether these subtypes represent distinct clinical entities or points on a severity continuum is controversial. Divergence in treatment response is a potential indicator of qualitative heterogeneity. This study examined smoking cessation response by ADHD subtype to osmotic-release oral system methylphenidate (OROS-MPH).

METHODS

Male and female adult smokers (ADHD-C = 167 and ADHD-IN = 87) were randomized to receive OROS-MPH or placebo as augmentation treatment to nicotine patch and counseling. Logistic regression was conducted to test the effect of OROS-MPH versus placebo on prolonged smoking abstinence by ADHD subtype.

RESULTS

The subtypes were similar in baseline demographic, smoking, and psychiatric history but differed in smoking cessation response to OROS-MPH or placebo as a function of nicotine dependence level. The 3-way interaction was significant; χ(2)(1) = 8.22, p < .01. Among highly dependent smokers, the prolonged abstinence rates were greater with OROS-MPH than with placebo in the ADHD-C group (60% vs. 31.3%, respectively, p < .05) but higher with placebo than with OROS-MPH in the ADHD-IN group (60% vs. 11.8%, respectively, p < .01). Abstinence rates did not differ by subtype or treatment among smokers who were less nicotine dependent.

CONCLUSION

Contrasting treatment response and divergence in the impact of nicotine dependence level support the hypothesis of ADHD subtypes as distinct clinical entities and may indicate the need and directions for personalized targeted treatments of smokers with ADHD.

Nicotine alters limbic function in adolescent rat by a 5-HT1A receptor mechanism

Epidemiological studies have shown that adolescent smoking is associated with health risk behaviors, including high-risk sexual activity and illicit drug use. Using rat as an animal model, we evaluated the behavioral and biochemical effects of a 4-day, low-dose nicotine pretreatment (60 μg/kg; intravenous) during adolescence and adulthood. Nicotine pretreatment significantly increased initial acquisition of cocaine self-administration, quinpirole-induced locomotor activity, and penile erection in adolescent rats, aged postnatal day (P)32. These effects were long lasting, remaining evident 10 days after the last nicotine treatment, and were observed when nicotine pretreatment was administered during early adolescence (P28-31), but not late adolescence (P38-41) or adulthood (P86-89). Neurochemical analyses of c-fos mRNA expression, and of monoamine transmitter and transporter levels, showed that forebrain limbic systems are continuing to develop during early adolescence, and that this maturation is critically altered by brief nicotine exposure. Nicotine selectively increased c-fos mRNA expression in the nucleus accumbens shell and basolateral amygdala in adolescent, but not adult animals, and altered serotonin markers in these regions as well as the prefrontal cortex. Nicotine enhancement of cocaine self-administration and quinpirole-induced locomotor activity was blocked by co-administration of WAY 100 635 (N-{2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl}-N-(2-pyridinyl)cyclohexanecarboxamide), a selective serotonin 1A (5-HT1A) receptor antagonist. Early adolescent pretreatment with the mixed autoreceptor/heteroceptor 5-HT1A receptor agonist, 8-OH-DPAT, but not the autoreceptor-selective agonist, S-15535, also enhanced quinpirole-induced locomotor activation. Nicotine enhancement of quinpirole-induced penile erection was not blocked by WAY 100 635 nor mimicked by 8-OH-DPAT. These findings indicate that early adolescent nicotine exposure uniquely alters limbic function by both 5-HT1A and non-5-HT1A receptor mechanisms.

Smoking withdrawal symptoms are more severe among smokers with ADHD and independent of ADHD symptom change: results from a 12-day contingency-managed abstinence trial

INTRODUCTION

Smokers with attention deficit hyperactivity disorder (ADHD) have greater difficulty quitting than those without ADHD, but preliminary data (McClernon, Kollins, Lutz, Fitzgerald, Murray, Redman, et al., 2008) suggest equivalent severity of withdrawal symptoms following brief abstinence. The objective of this study was to characterize the differential effects of intermediate term smoking abstinence on self-reported withdrawal and ADHD symptoms in adult smokers with and without ADHD.

METHODS

Forty adult (50% female), nontreatment seeking moderate-to-heavy smokers with and without ADHD were enrolled in a 12-day quit study in which monetary incentives were provided for maintaining biologically verified abstinence. Self-reported withdrawal, mood, and ADHD symptoms were measured pre- and post-quitting.

RESULTS

ADHD and controls did not vary on smoking or demographic variables. Significant Group × Session interactions were observed across a broad range of withdrawal symptoms and were generally characterized by greater withdrawal severity among ADHD smokers, particularly during the first 5 days of abstinence. In addition, Group × Sex × Session interactions were observed for craving, somatic symptoms, negative affect, and habit withdrawal; these interactions were driven by greater withdrawal severity among females with ADHD. Group × Session interactions were not observed for ADHD symptom scales.

CONCLUSIONS

The results of this study suggest that smokers with ADHD, and ADHD females in particular, experience greater withdrawal severity during early abstinence-independent of effects on ADHD symptoms. Whereas additional research is needed to pinpoint mechanisms, our findings suggest that smoking cessation interventions targeted at smokers with ADHD should address their more severe withdrawal symptoms following quitting.

Impact of attention-deficit/hyperactivity disorder (ADHD) treatment on smoking cessation intervention in ADHD smokers: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

High smoking rates in adults with attention-deficit/hyperactivity disorder (ADHD) and nicotine's amelioration of ADHD suggest that effective ADHD treatment might facilitate abstinence in smokers with ADHD. The present study evaluated if using osmotic-release oral system methylphenidate (OROS-MPH) to treat ADHD enhances response to smoking cessation treatment in smokers with ADHD.

METHOD

A randomized, double-blind, placebo-controlled, 11-week trial with a 1-month follow-up was conducted at 6 clinical sites between December 2005 and January 2008. Adults (aged 18-55 years) meeting DSM-IV criteria for ADHD and interested in quitting smoking were randomly assigned to OROS-MPH titrated to 72 mg/d (n = 127) or placebo (n = 128). All participants received brief weekly individual smoking cessation counseling for 11 weeks and 21 mg/d nicotine patches starting on the smoking quit day (day 27) through study week 11. Outcome measures included prolonged smoking abstinence and DSM-IV ADHD Rating Scale (ADHD-RS) score.

RESULTS

Of 255 randomly assigned participants, 204 (80%) completed the trial. Prolonged abstinence rates, 43.3% and 42.2%, for the OROS-MPH and placebo groups, respectively, did not differ significantly (OR = 1.1; 95% CI, 0.63-1.79; P = .81). Relative to placebo, OROS-MPH evidenced a greater reduction in DSM-IV ADHD-RS score (P < .0001) and in cigarettes per day during the post-quit phase (P = .016). Relative to placebo, OROS-MPH increased blood pressure and heart rate to a statistically, but not clinically, significant degree (P < .05); medication discontinuation did not differ significantly between treatments.

CONCLUSIONS

Treatment for ADHD did not improve smoking cessation success; OROS-MPH, relative to placebo, effectively treated ADHD and was safe and generally well tolerated in this healthy sample of adult ADHD smokers.

TRIAL REGISTRATION

clinical trials.gov Identifier: NCT00253747.

Monetary incentives promote smoking abstinence in adults with attention deficit hyperactivity disorder (ADHD)

Individuals with attention deficit hyperactivity disorder (ADHD) smoke at rates significantly higher than the general population and have more difficulty quitting than nondiagnosed individuals. Currently, there are no evidence-based approaches for reducing smoking specifically in individuals with ADHD. Adult regular smokers with or without ADHD participated in a study of extended smoking withdrawal where monetary incentives were used to promote abstinence. Participants were paid according to an escalating schedule for maintaining abstinence measured as self-report of no smoking and an expired air carbon monoxide (CO) level of <or=4 parts per million. Sixty-four percent (14/22) of smokers with ADHD and 50% (11/22) of smokers without ADHD maintained complete abstinence for the 2-week duration of the study. Twenty-two percent (5/22) and 9% (2/22) of smokers with ADHD and without ADHD, respectively, maintained continued abstinence for up to 10 days following the removal of the contingencies. Though abstinence rates were higher for the smokers with ADHD, the group differences were not statistically significant. Results suggest that monetary incentives may be a useful approach for promoting abstinence in adult smokers with ADHD, perhaps owing to altered reinforcement processes in these individuals.

Relationship between cigarette smoking and childhood symptoms of inattention and hyperactivity/impulsivity in alcohol-dependent adults without attention-deficit hyperactivity disorder

BACKGROUND

Symptoms of inattention and hyperactivity/impulsivity that fall below the DSM-IV diagnostic threshold for attention-deficit hyperactivity disorder (ADHD) may be associated with the high prevalence of smoking among individuals with alcohol dependence, yet no studies to date have examined the relationship between subthreshold ADHD symptoms and cigarette smoking in this group. We hypothesized that increasing levels of ADHD symptoms would be associated with increasing risk of lifetime smoking and nicotine dependence, concentration problems secondary to nicotine withdrawal, and maintenance of smoking.

METHODS

Participants were alcohol-dependent adults (n = 242) who did not meet criteria for ADHD or a current Axis I disorder other than alcohol and nicotine dependence. All participants were involved in treatment for alcohol dependence but not smoking cessation. The Semi-Structured Assessment for the Genetics of Alcoholism was administered to collect demographic and smoking history data and to assess symptoms of ADHD and other psychiatric disorders.

RESULTS

A higher number of self-reported ADHD symptoms were associated with increased likelihood of ever smoking (p = .026), nicotine dependence (p = .017), and impaired concentration as a symptom of nicotine withdrawal (p = .046). There was no relationship between the number of ADHD symptoms and classification as a former versus current smoker (p = .333).

CONCLUSIONS

Childhood symptoms of inattention and hyperactivity/impulsivity are related to cigarette smoking and nicotine dependence among alcohol-dependent individuals at levels below the ADHD diagnostic threshold. Conceptualization of ADHD symptoms as occurring on a continuum may aid identification of and early intervention for individuals who are at highest risk for initiating smoking and developing nicotine dependence.

Smoking, nicotine and neuropsychiatric disorders

Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.

Is the inhibition of nicotinic acetylcholine receptors by bupropion involved in its clinical actions?

In this mini review we will focus on those molecular and cellular mechanisms exerted by bupropion (BP), ultimately leading to the antidepressant and anti-nicotinic properties described for this molecule. The main pharmacological mechanism is based on the fact that BP induces the release as well as inhibits the reuptake of neurotransmitters such as a dopamine (DA) and norepinephrine (NE). Additional mechanisms of action have been also determined. For example, BP is a noncompetitive antagonist (NCA) of several nicotinic acetylcholine receptors (AChRs). Based on this evidence, the dual antidepressant and anti-nicotinic activity of BP is currently considered to be mediated by its stimulatory action on the DA and NE systems as well as its inhibitory action on AChRs. Considering the results obtained in the archetypical mouse muscle AChR, a sequential mechanism can be hypothesized to explain the inhibitory action of BP on neuronal AChRs: (1) BP first binds to AChRs in the resting state, decreasing the probability of ion channel opening, (2) the remnant fraction of open ion channels is subsequently decreased by accelerating the desensitization process, and (3), BP interacts with a binding domain located between the serine (position 6') and valine (position 13') rings that is shared with the NCA phencyclidine and other tricyclic antidepressants. This new evidence paves the way for further investigations using AChRs as targets for the action of safer antidepressants and novel anti-addictive compounds.

Pharmacological and neurotoxicological actions mediated by bupropion and diethylpropion

The antiappetite agent diethylpropion (DEP), and the antidepressant and antismoking aid compound bupropion (BP), not only share the same structural motif but also present similar mechanisms of action in the CNS. For example, both drugs induce the release as well as inhibit the reuptake of neurotransmitters such as a dopamine (DA) and norepinephrine (NE). In general, they produce mild side effects, including reversible psychomotor alterations mostly in geriatric patients (by BP), or moderate changes in neurotransmitter contents linked to oxidative damage (by DEP). Therefore, attention must be paid during any therapeutic use of these agents. Regarding the interaction of BP with the DA transporter, residues S359, located in the middle of TM7, and A279, located close to the extracellular end of TM5, contribute to the binding and blockade of translocation mediated by BP, respectively. Additional mechanisms of action have also been determined for each compound. For example, BP is a noncompetitive antagonist (NCA) of several nicotinic acetylcholine receptors (AChRs). Based on this evidence, the dual antidepressant and antinicotinic activity of BP is currently considered to be mediated by its stimulatory action on DA and NE systems as well as its inhibitory action on AChRs. Considering the results obtained in the archetypical mouse muscle AChR, a sequential mechanism can be hypothesized to explain the inhibitory action of BP on neuronal AChRs: (1) BP first binds to AChRs in the resting state, decreasing the probability of ion channel opening, (2) the remnant fraction of open ion channels is subsequently decreased by accelerating the desensitization process, and finally (3) BP interacts with a binding domain located between the serine (position 9') and valine (position 13') rings that is shared with the NCA phencyclidine and other tricyclic antidepressants. The homologous location in the alpha3beta4 AChR is between the serine and valine/phenylalanine rings. This new evidence opens a window for further investigation using AChRs as targets for the action of safer antidepressants and novel antiaddictive compounds.

Impulsivity and cigarette craving: differences across subtypes

RATIONALE

Cigarette smoking has been linked to a number of personality characteristics, including impulsivity. Smokers tend to endorse high levels of impulsivity, and more impulsive smokers have greater difficulty quitting, but little is known about potential explanatory mechanisms. Although indirect evidence suggests craving as a candidate mechanism, direct evidence has been mixed.

MATERIALS AND METHODS

This study assessed whether specific aspects of impulsivity (sensation seeking, lack of premeditation, lack of perseverance, and urgency) were associated with cue-induced craving. Regular smokers (n = 60; 50% female) were exposed to a smoking cue and a neutral cue in a repeated measure counter-balanced design.

RESULTS

Mixed effects regression models indicated that smokers who were high in sensation seeking reported greater increases in appetitive craving after smoking cue exposure, whereas, smokers who were high in urgency and lack of perseverance reported greater increases in negative affect craving.

CONCLUSIONS

Findings suggest a complex relationship between impulsivity and cue-induced craving that may be masked by single construct conceptualizations of impulsivity.