Effect of varenicline on individual nicotine withdrawal symptoms: a combined analysis of eight randomized, placebo-controlled trials

Obstructive Sleep Apnea and Smoking Increase the Risk of Cardiovascular Disease: Smoking Cessation Pharmacotherapy

Tobacco smoking has been a recognized risk factor for cardiovascular diseases (CVD). Smoking is a chronic relapsing disease and pharmacotherapy is a main component of smoking cessation. Obstructive sleep apnea (OSA) and smoking both increase the risk of CVD and are associated with significant morbidity and mortality. There are few existing data examining how pharmacological treatment, such as nicotine replacement therapy (NRT), bupropion, and varenicline, affect smokers suffering with OSA and especially their cardiovascular effects. The aim of this review was to evaluate the effects of smoking cessation pharmacotherapy on OSA with a special emphasis on the cardiovascular system. Results: Only small studies have assessed the effect of NRTs on OSA. Nicotine gum administration showed an improvement in respiratory events but with no permanent results. No specific studies were found on the effect of bupropion on OSA, and a limited number evaluated varenicline's effects on sleep and specifically OSA. Varenicline administration in smokers suffering from OSA reduced the obstructive respiratory events, especially during REM. Studies on second-line medication (nortriptyline, clonidine, cytisine) are even more limited. There are still no studies evaluating the cardiovascular effects of smoking cessation medications on OSA patients. Conclusions: Sleep disturbances are common withdrawal effects during smoking cessation but could be also attributed to pharmacotherapy. Smokers should receive personalized treatment during their quitting attempts according to their individual needs and problems, including OSA. Future studies are needed in order to evaluate the efficacy and safety of smoking cessation medications in OSA patients.

Bayesian regularization to predict neuropsychiatric adverse events in smoking cessation with pharmacotherapy

BACKGROUND

Research on risk factors for neuropsychiatric adverse events (NAEs) in smoking cessation with pharmacotherapy is scarce. We aimed to identify predictors and develop a prediction model for risk of NAEs in smoking cessation with medications using Bayesian regularization.

METHODS

Bayesian regularization was implemented by applying two shrinkage priors, Horseshoe and Laplace, to generalized linear mixed models on data from 1203 patients treated with nicotine patch, varenicline or placebo. Two predictor models were considered to separate summary scores and item scores in the psychosocial instruments. The summary score model had 19 predictors or 26 dummy variables and the item score model 51 predictors or 58 dummy variables. A total of 18 models were investigated.

RESULTS

An item score model with Horseshoe prior and 7 degrees of freedom was selected as the final model upon model comparison and assessment. At baseline, smokers reporting more abnormal dreams or nightmares had 16% greater odds of experiencing NAEs during treatment (regularized odds ratio (rOR) = 1.16, 95% credible interval (CrI) = 0.95 - 1.56, posterior probability P(rOR > 1) = 0.90) while those with more severe sleep problems had 9% greater odds (rOR = 1.09, 95% CrI = 0.95 - 1.37, P(rOR > 1) = 0.85). The prouder a person felt one week before baseline resulted in 13% smaller odds of having NAEs (rOR = 0.87, 95% CrI = 0.71 - 1.02, P(rOR < 1) = 0.94). Odds of NAEs were comparable across treatment groups. The final model did not perform well in the test set.

CONCLUSIONS

Worse sleep-related symptoms reported at baseline resulted in 85%-90% probability of being more likely to experience NAEs during smoking cessation with pharmacotherapy. Treatment for sleep disturbance should be incorporated in smoking cessation program for smokers with sleep disturbance at baseline. Bayesian regularization with Horseshoe prior permits including more predictors in a regression model when there is a low number of events per variable.

Evaluating Treatment Mechanisms of Varenicline: Mediation by Affect and Craving

INTRODUCTION

Negative reinforcement models posit that relapse to cigarette smoking is driven in part by changes in affect and craving during the quit attempt. Varenicline may aid cessation by attenuating these changes; however, this mediational pathway has not been formally evaluated in placebo-controlled trials. Thus, trajectories of negative affect (NA), positive affect (PA), and craving were tested as mediators of the effect of varenicline on smoking cessation.

AIMS AND METHODS

Secondary data analysis was conducted on 828 adults assigned to either varenicline or placebo in a randomized controlled trial for smoking cessation (NCT01314001). Self-reported NA, PA, and craving were assessed 1-week pre-quit, on the target quit day (TQD), and 1 and 4 weeks post-TQD.

RESULTS

Across time, NA peaked 1-week post-quit, PA did not change, and craving declined. Less steep rises in NA (indirect effect 95% CI: .01 to .30) and lower mean craving at 1-week post-quit (CI: .06 to .50) were mediators of the relationship between varenicline and higher cessation rates at the end of treatment. PA was associated with cessation but was not a significant mediator.

CONCLUSIONS

These results partially support the hypothesis that varenicline improves smoking cessation rates by attenuating changes in specific psychological processes and supported NA and craving as plausible treatment mechanisms of varenicline.

IMPLICATIONS

The present research provides the first evidence from a placebo-controlled randomized clinical trial that varenicline's efficacy is due, in part, to post-quit attenuation of NA and craving. Reducing NA across the quit attempt and craving early into the attempt may be important treatment mechanisms for effective interventions. Furthermore, post-quit NA, PA, and craving were all associated with relapse and represent treatment targets for future intervention development.

Does Smoking Affect OSA? What about Smoking Cessation?

The connection between smoking and Obstructive sleep apnea (OSA) is not yet clear. There are studies that have confirmed the effect of smoking on sleep disordered breathing, whereas others did not. Nicotine affects sleep, as smokers have prolonged total sleep and REM latency, reduced sleep efficiency, total sleep time, and slow wave sleep. Smoking cessation has been related with impaired sleep. The health consequences of cigarette smoking are well documented, but the effect of smoking cessation on OSA has not been extensively studied. Smoking cessation should improve OSA as upper airway oedema may reduce, but there is limited data to support this hypothesis. The impact of smoking cessation pharmacotherapy on OSA has been studied, especially for nicotine replacement therapy (NRT). However, there are limited data on other smoking cessation medications as bupropion, varenicline, nortriptyline, clonidine, and cytisine. The aim of this review was to explore the current evidence on the association between smoking and OSA, to evaluate if smoking cessation affects OSA, and to investigate the possible effects of different pharmacologic strategies offered for smoking cessation on OSA.

Varenicline as a treatment for cannabis use disorder: A placebo-controlled pilot trial

BACKGROUND

An efficacious pharmacotherapy for cannabis use disorder (CUD) has yet to be established. This study preliminarily evaluated the safety and efficacy of varenicline for CUD in a proof-of-concept clinical trial.

METHODS

Participants in this 6-week randomized, placebo-controlled pilot trial received either varenicline (n = 35) or placebo (n = 37), added to a brief motivational enhancement therapy intervention. Outcomes included cannabis withdrawal, cannabis abstinence, urine cannabinoid levels, percent cannabis use days, and cannabis sessions per day.

RESULTS

Both treatment groups noted significant decreases in self-reported cannabis withdrawal, percentage of days used, and use sessions per day during treatment compared to baseline. While this pilot trial was not powered to detect statistically significant between-group differences, participants randomized to varenicline evidenced numerically greater rates of self-reported abstinence at the final study visit [Week 6 intent-to-treat (ITT): Varenicline: 17.1% vs. Placebo: 5.4%; RR = 3.2 (95% CI: 0.7,14.7)]. End-of-treatment urine creatinine corrected cannabinoid levels were numerically lower in the varenicline group and higher in the placebo group compared to baseline [Change from baseline: Varenicline -1.7 ng/mg (95% CI: -4.1,0.8) vs. Placebo: 1.9 ng/mg (95% CI: -0.4,4.3); Δ = 3.5 (95% CI: 0.1,6.9)]. Adverse events related to study treatment did not reveal new safety signals.

CONCLUSIONS

Findings support the feasibility of conducting clinical trials of varenicline as a candidate pharmacotherapy for CUD, and indicate that a full-scale efficacy trial, powered based on effect sizes and variability yielded in this study, is warranted.

Temporal networks of tobacco withdrawal symptoms during smoking cessation treatment

A recently developed network perspective on tobacco withdrawal posits that withdrawal symptoms causally influence one another across time, rather than simply being indicators of a latent syndrome. Evidence supporting a network perspective would shift the focus of tobacco withdrawal research and intervention toward studying and treating individual withdrawal symptoms and intersymptom associations. Here we construct and examine temporal tobacco withdrawal networks that describe the interplay among withdrawal symptoms across time using experience-sampling data from 1,210 participants (58.35% female, 86.24% White) undergoing smoking cessation treatment. We also construct person-specific withdrawal networks and capture individual differences in the extent to which withdrawal symptom networks promote the spread of symptom activity through the network across time using impulse response analysis. Results indicate substantial moment-to-moment associations among withdrawal symptoms, substantial between-person differences in withdrawal network structure, and reductions in the interplay among withdrawal symptoms during combination smoking cessation treatment. Overall, findings suggest the utility of a network perspective and also highlight challenges associated with the network approach stemming from vast between-person differences in symptom networks. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cardiovascular and neuropsychiatric safety of smoking cessation pharmacotherapies in non-depressed adults: a retrospective cohort study

BACKGROUND AND AIMS

Pharmacotherapies for smoking cessation are widely prescribed, despite substantial concerns being raised regarding the potential increased risk of cardiovascular (CV) and neuropsychiatric adverse events associated with these treatments. This study aimed to assess the relative CV and neuropsychiatric safety between varenicline and bupropion compared with nicotine replacement therapies (NRT) in adults without a recent history of depression.

DESIGN

Retrospective new-user cohort study.

SETTING

US administrative data from 2006 to 2016 covering more than 100 million individuals.

PARTICIPANTS

Three study cohorts of new users, aged 18 years or older, limited to patients with no diagnosis or treatment for depression in the prior 12 months.

MEASUREMENTS

Propensity score adjusted log-binomial regression models. The primary outcome was a composite of hospitalized CV events. Secondary outcomes included a composite of hospitalized neuropsychiatric events and individual components of the primary outcome.

FINDINGS

A total of 618 497 participants were included in our study cohorts. Compared with NRT (n = 32 237), varenicline (n = 454 698) was associated with a 20% lower 1-year CV risk [adjusted relative risk (RR) = 0.80, 95% confidence interval (CI) = 0.75-0.85], and bupropion (n = 131 562) was associated with a 25% lower 1-year CV risk (RR = 0.75, 95% CI = 0.69-0.81). Varenicline was associated with a 35% lower 1-year risk of neuropsychiatric hospitalization versus NRT (RR = 0.65, 95% CI = 0.59-0.72), and bupropion was associated with a 21% increase in 1-year risk of neuropsychiatric hospitalization (RR = 1.21, 95% CI = 1.09-1.35).

CONCLUSION

Varenicline compared with nicotine replacement therapy does not appear to be associated with an increased risk of cardiovascular or neuropsychiatric hospitalizations. Bupropion appears to be associated with a lower risk of cardiovascular hospitalization and a higher risk of neuropsychiatric hospitalization, compared with nicotine replacement therapy.

Varenicline: mode of action, efficacy, safety and accumulated experience salient for clinical populations

Objective: Varenicline, a selective partial agonist of the α4β2 nicotinic acetylcholine receptor, is a smoking cessation pharmacotherapy that more than doubles the chance of quitting smoking at 6 months compared with placebo. This article reviews salient knowledge of the discovery, pharmacological characteristics, and the efficacy and safety of varenicline in general and in specific populations of smokers and provides recommendations to support use in clinical practice.Methods: Literature searches for varenicline were conducted using PubMed, with date limitations of 2000-2018 inclusive, using search terms covering the discovery, mechanism of action, pharmacokinetics, efficacy and safety in different populations of smokers, alternative quit approaches and combination therapy. Selection of safety and efficacy data was limited to clinical trials, meta-analyses and observational studies.Results: Standard administration of varenicline is efficacious in helping smokers to quit, including smokers with cardiovascular disease and chronic obstructive pulmonary disease. Furthermore, varenicline efficacy may be improved with pre-loading, a gradual quitting approach for smokers unwilling or unable to quit abruptly, and extended treatment in smokers who have recently quit to help maintain abstinence. Initial concerns regarding the association of varenicline with increased risk of neuropsychiatric and cardiovascular adverse events have been disproven after extensive clinical evaluations, and the benefit-risk profile of varenicline is considered favorable.Conclusions: Varenicline is efficacious and safe for all adult smokers with a range of clinical characteristics. Evidence suggests that approaches offering greater flexibility in timing and duration of treatment may further extend treatment efficacy and clinical reach.

The effect of varenicline on mood and cognition in smokers with HIV

RATIONALE

Barriers to smoking cessation, including negative affect and cognitive dysfunction, may contribute to high smoking rates among people living with HIV/AIDS (PLWH). Varenicline may help PLWH quit smoking by improving mood and cognition, yet this has not been explored.

OBJECTIVES

The goal of this study was to evaluate the effect of varenicline on mood and cognition among PLWH enrolled in a smoking cessation clinical trial.

METHODS

In this secondary analysis of a varenicline trial (NCT01710137), we assessed mood (depression, anxiety) and cognition (attention, working memory) at weeks 0 (baseline), 1, 3, and 12 (end-of-treatment, EOT). Primary outcomes were changes in mood and cognition from baseline to EOT. Secondarily, mood and cognition were evaluated as predictors of biochemically confirmed 7-day point-prevalence abstinence at EOT.

RESULTS

Overall, 173 subjects (87 varenicline, 86 placebo) were included. At EOT, varenicline reduced anxiety (P < 0.001), vs. placebo (P = 0.31; interaction P = 0.05). Across both treatment arms, reductions in anxiety from baseline to EOT were associated with a higher likelihood of abstinence (OR = 1.3, 95% CI 1.1 to 1.6, P = 0.01). There were no significant treatment by time interactions for cognition or depression.

CONCLUSIONS

These data suggest that varenicline operates, at least in part, by reducing anxiety. Anxiety should be an intervention target for smokers with HIV interested in quitting.

The Network Structure of Tobacco Withdrawal in a Community Sample of Smokers Treated With Nicotine Patch and Behavioral Counseling

INTRODUCTION

Network theories of psychopathology highlight that, rather than being indicators of a latent disorder, symptoms of disorders can causally interact with one another in a network. This study examined tobacco withdrawal from a network perspective.

METHODS

Participants (n = 525, 50.67% female) completed the Minnesota Tobacco Withdrawal Scale four times (2 weeks prior to a target quit day, on the target quit day, and 4 and 8 weeks after the target quit day) over the course of 8 weeks of treatment with nicotine patch and behavioral counseling within a randomized clinical trial testing long-term nicotine patch therapy in treatment-seeking smokers. The conditional dependence among seven withdrawal symptoms was estimated at each of the four measurement occasions. Influential symptoms of withdrawal were identified using centrality indices. Changes in network structure were examined using the Network Comparison Test.

RESULTS

Findings indicated many associations among the individual symptoms of withdrawal. The strongest associations that emerged were between sleep problems and restlessness, and associations among affective symptoms. Restlessness and affective symptoms emerged as the most central symptoms in the withdrawal networks. Minimal differences in the structure of the withdrawal networks emerged across time.

CONCLUSIONS

The cooccurrence of withdrawal symptoms may result from interactions among symptoms of withdrawal rather than simply reflecting passive indicators of a latent disorder. Findings encourage greater consideration of individual withdrawal symptoms and their potential interactions and may be used to generate hypotheses that may be tested in future intensive longitudinal studies.

IMPLICATIONS

This study provides a novel, network perspective on tobacco withdrawal. Drawing on network theories of psychopathology, we suggest that the cooccurrence of withdrawal symptoms may result from interactions among symptoms of withdrawal over time, rather than simply reflecting passive indicators of a latent disorder. Results indicating many associations among individual symptoms of withdrawal are consistent with a network perspective. Other results of interest include minimal changes in the network structure of withdrawal across four measurement occasions prior to and during treatment with nicotine patch and behavioral counseling.

Sleep as a Target for Optimized Response to Smoking Cessation Treatment

Declining national rates of current tobacco use to an all-time low of 15.1% represents a public health victory. Undermining this progress, however, are smoking rates of up to 50% among high-risk, low-income populations. Current FDA-approved treatments for nicotine dependence are ineffective with between 70-95% of treatment-seekers relapsing within the first year of attempted abstinence. Thus, identification of novel intervention targets to optimize response to currently available treatments for nicotine dependence is a critical next step. One such target may be sleep insomnia. Insomnia is a clinically verified nicotine withdrawal symptom but, to date, addressing insomnia or other sleep disturbance symptoms as an adjunctive smoking cessation therapy has yet to be fully considered. To this end, this manuscript presents a narrative review of: (1) sleep continuity and architecture in smokers versus nonsmokers; (2) effects of nicotine abstinence on sleep; (3) possible mechanisms linking sleep with smoking cessation outcomes; (4) plausible adjunctive sleep therapies to promote smoking cessation; (5) possible treatments for unhealthy sleep in smokers; and (6) directions for future research. Taken together, this will provide conceptual support for sleep therapy as an adjunctive treatment for smoking cessation.

Implications

This narrative literature review presents a comprehensive discussion of the relationship between habitual sleep and cigarette smoking. The extent to which unhealthy sleep in smokers may be a viable intervention target for promoting response to smoking cessation treatment is considered. Ultimately, this review provides conceptual support for sleep therapy as an adjunctive treatment for smoking cessation.

Effects of Varenicline, Depressive Symptoms, and Region of Enrollment on Smoking Cessation in Depressed Smokers

Introduction

Despite effective treatments, relapse to smoking remains a vexing global health problem. One predictor of relapse is depressive symptoms. Medications such as varenicline reduce withdrawal-related symptoms of depression, reducing relapse. This study examined whether varenicline moderated the effect of depressive symptoms on relapse, and whether this varied by region of enrollment.

Methods

Adult smokers (n = 525; 37% male) with past or current, stable major depressive disorder recruited from United States (n = 255), and European (n = 270) sites participated in a randomized, double-blind cessation treatment trial including 12 weeks of varenicline or placebo, with 40-week nontreatment follow-up.

Results

Longitudinal and binary logistic regressions were used to model the probability of sustained abstinence by end of treatment and point-prevalence abstinence in follow-up. The association between depression symptoms and abstinence was moderated by intervention group at end of treatment, and by region during follow-up: more severe symptoms were associated with end-of-treatment relapse for placebo (odds ratio [OR] = 0.91, p = .003), but not varenicline (OR = 0.99, p = .568). During follow-up, increased symptoms of depression predicted greater likelihood of smoking for European (p = .009) but not US participants. Europeans were more likely to be abstinent for both outcomes (p < .01).

Conclusions

These results extend studies demonstrating varenicline is associated with less withdrawal-related depression, and suggest it aids cessation even in smokers with depressive symptoms. Findings also suggest regional differences in the relationship between depressive symptoms and cessation that may be related to differences in prevalence.

Implications

This study indicates varenicline may aid cessation partially by reducing withdrawal-related symptoms of depression. It also suggests that the impact of depressive symptoms on cessation varies regionally, and that this variation may be related to differences in smoking prevalence.

Pilot Randomized Trial of an Automated Smoking Cessation Intervention via Mobile Phone Text Messages as an Adjunct to Varenicline in Primary Care

OBJECTIVE

Varenicline is a safe and effective aid to smoking cessation but most trials have involved frequent visits or intensive behavioral support unlike that typically provided in primary care. The current study examined if motivational text messages, sent via cellphone, would increase quit rates in smokers being treated with varenicline and 3 brief sessions in a family practice setting.

METHODS

This study was a randomized controlled, parallel-group smoking cessation trial. Intervention group participants (n = 74) received daily motivational text messages, additional texted tips in response to keywords, and weekly study questions while control group participants (n = 76) received only weekly study questions. Both groups received individualized counseling. Self-reported non-smoking and exhaled breath CO <10ppm were used to validate smoking abstinence at 3 weeks and 12 weeks.

RESULTS

Overall, 30.7% (46/150) of participants were abstinent at the 12 week follow-up and the abstinence rate did not differ between groups (INT 31.1% v. CON 30.3%, p = .91). The only predictor of abstinence at 12 weeks was use of varenicline during a previous quit attempt (p = .01). Intervention group participants were more likely to rate the text messaging program as good or excellent (p < .01), to recommend a similar program to family or friends (p < .01), and to complete positive smoking cessation activities (p = .04), when compared with the control group.

CONCLUSION

Although there were no differences in quit rates between the intervention and control group, intervention group participants rated the text messaging system more favorably, were more likely to recommend the program to others, and were more likely to complete positive smoking cessation activities.

Moderators of smoking cessation outcomes in a randomized-controlled trial of varenicline versus placebo

RATIONALE AND OBJECTIVE

Varenicline has gained a reputation as the optimal intervention for treatment resistant smokers, yet more than half of those who try it do not succeed. To better understand individual differences in the effectiveness of varenicline, this study evaluates the effectiveness of varenicline for smoking cessation in a double-blind, placebo-controlled, randomized clinical trial and examines the influence of psychological factors on treatment outcome.

METHOD

Two hundred five cigarette smokers interested in quitting were randomly assigned to 12 weeks of varenicline or placebo. Outcomes examined were CO-confirmed continuous abstinence for the past month, average number of cigarettes smoked per day, and 7-day point prevalence.

RESULTS

Varenicline-treated participants were more likely than placebo to achieve continuous abstinence at the end of treatment (OR = 3.29; RR = 2.62), and 7-day point prevalence rates showed an effect of medication at each time point. Participants in both groups significantly reduced their smoking during the course of treatment and follow-up, and the medication by visit interaction was significant in the expected direction. Impulsivity and personality style emerged as moderators of the relationship between medication condition and treatment outcome.

CONCLUSIONS

In addition to replicating efficacy results for varenicline versus placebo, the present study shows that the efficacy of pharmacotherapy is influenced by psychological factors. In an era where pharmacotherapy is often perceived as the "silver bullet," we are reminded that smoking cessation is a dynamic process and intervention must be adaptable to address individual differences.

Emerging pharmacotherapies for alcohol use disorder

The identification of different stages within the alcohol use disorder (AUD) cycle that are linked to neurocircuitry changes in pathophysiology associated with the negative emotional states of abstinence has provided a view of medication development for AUD that emphasizes changes in the brain reward and stress systems. Alcohol use disorder can be defined as a chronic relapsing disorder that involves compulsive alcohol seeking and taking, loss of control over alcohol intake, and emergence of a negative emotional state during abstinence. The focus of early medications development was to block the motivation to seek alcohol in the binge/intoxication stage. More recent work has focused on reversing the motivational dysregulations associated with the withdrawal/negative affect and preoccupation/anticipation stages during protracted abstinence. Advances in our understanding of the neurocircuitry and neuropharmacological mechanisms that are involved in the development and maintenance of the withdrawal/negative affect stage using validated animal models have provided viable targets for future medications. Another major advance has been proof-of-concept testing of potential therapeutics and clinical validation of relevant pharmacological targets using human laboratory models of protracted abstinence. This review focuses on future targets for medication development associated with reversal of the loss of reward function and gain in brain stress function that drive negative reinforcement in the withdrawal/negative affect stage of addiction. Basic research has identified novel neurobiological targets associated with the withdrawal/negative affect stage and preoccupation/anticipation stage, with a focus on neuroadaptive changes within the extended amygdala that account for the transition to dependence and vulnerability to relapse. This article is part of the Special Issue entitled "Alcoholism".

Neuropeptide systems and new treatments for nicotine addiction

RATIONALE

The mildly euphoric and cognitive enhancing effects of nicotine play a role in the initiation of smoking, while dysphoria and anxiety associated with smoking cessation contribute to relapse. After the acute withdrawal phase, smoking cues, a few cigarettes (i.e., lapse), and stressors can cause relapse. Human and animal studies have shown that neuropeptides play a critical role in nicotine addiction.

OBJECTIVES

The goal of this paper is to describe the role of neuropeptide systems in the initiation of nicotine intake, nicotine withdrawal, and the reinstatement of extinguished nicotine seeking.

RESULTS

The reviewed studies indicate that several drugs that target neuropeptide systems diminish the rewarding effects of nicotine by preventing the activation of dopaminergic systems. Other peptide-based drugs diminish the hyperactivity of brain stress systems and diminish withdrawal-associated symptom severity. Blockade of hypocretin-1 and nociceptin receptors and stimulation of galanin and neurotensin receptors diminishes the rewarding effects of nicotine. Both corticotropin-releasing factor type 1 and kappa-opioid receptor antagonists diminish dysphoria and anxiety-like behavior associated with nicotine withdrawal and inhibit stress-induced reinstatement of nicotine seeking. Furthermore, blockade of vasopressin 1b receptors diminishes dysphoria during nicotine withdrawal, and melanocortin 4 receptor blockade prevents stress-induced reinstatement of nicotine seeking. The role of neuropeptide systems in nicotine-primed and cue-induced reinstatement is largely unexplored, but there is evidence for a role of hypocretin-1 receptors in cue-induced reinstatement of nicotine seeking.

CONCLUSION

Drugs that target neuropeptide systems might decrease the euphoric effects of smoking and improve relapse rates by diminishing withdrawal symptoms and improving stress resilience.

Factor Analysis and Psychometric Properties of the Minnesota Nicotine Withdrawal Scale and the Minnesota Nicotine Withdrawal Scale-Revised: Italian Version

BACKGROUND/AIMS

We run Exploratory and Confirmatory Factor Analyses of the Minnesota Nicotine Withdrawal Scale (MNWS) and of the MNWS-Revised (MNWS-R). Psychometric properties were also explored.

METHODS

Adult Italian smokers, 366 in all, were assessed via the MNWS-R together with rating scales measuring cigarette dependence, alcohol use, anxiety sensitivity and negative affect at baseline and after 3 months.

RESULTS

The MNWS showed good psychometric properties (α = 0.85; rtt = 0.59) and a unidimensional factor structure. The 2-factor model of MNWS-R had the best fit and the factors were labelled psychological symptoms (α = 0.86; rtt = 0.59) and associated somatic features (α = 0.64; rtt = 0.45).

CONCLUSIONS

MNWS showed 1 factor; MNWS-R showed 2 relatively dependent factors. The results need to be replicated in smokers in withdrawal.

A Randomized Trial Evaluating Whether Topiramate Aids Smoking Cessation and Prevents Alcohol Relapse in Recovering Alcohol-Dependent Men

BACKGROUND

Alcohol and nicotine dependence frequently co-occur, and quitting smoking might enhance long-term alcohol abstinence. Topiramate appears to help non-alcohol-dependent individuals quit smoking, and our pilot work suggested efficacy only in men. It also prevents relapse to alcohol in recently detoxified alcoholics. We evaluated topiramate in abstinent alcohol-dependent men to assess whether this medication (i) promotes smoking cessation and (ii) prevents alcohol and other drug relapse in the context of smoking cessation treatment.

METHODS

One hundred and twenty-nine alcohol-abstinent (mean ~6 months) alcohol-dependent male smokers (80% with other substance use disorders) participated in this 12-week randomized, double blind, parallel group comparison of topiramate (up to 200 mg/d) and placebo with a 24-week nontreatment follow-up period. The study was carried out sequentially at 2 academic centers in the Midwest and Southern California between March 23, 2009 and November 20, 2014. All participants received manual-guided smoking cessation counseling combined with medication-focused compliance enhancement therapy. Randomization was block designed by the research pharmacist in a 1:1 ratio. Participants, investigators, and research personnel were masked to treatment assignment. The primary smoking end point was biochemically confirmed 4-week continuous abstinence from smoking during weeks 9 to 12, while the secondary end point was relapse to any drinking or drug use during the entire 36-week evaluation period. Logistic regression was used to determine the effects of topiramate on quitting smoking and alcohol relapse, controlling for relevant covariates. The trial is registered at ClinicalTrials.gov (number NCT00802412) and is now closed.

RESULTS

Only a small proportion (7.9%) of topiramate-treated participants were able to quit smoking, and this cessation rate was similar to placebo (10.6%; odds ratio = 1.60; 95% confidence interval 0.4, 6.5; p = 0.51). Roughly 30% of the sample had a documented relapse to drinking or drug use during the study, and these rates were similar in the topiramate (20/63; 31.8%) and placebo groups (18/66; 27.3%; p = 0.58). Results of a longitudinal logistic regression model examining time to any alcohol relapse revealed no medication effect.

CONCLUSIONS

Topiramate at a daily dosage of up to 200 mg per day, combined with smoking cessation and medication adherence counseling, had no effects on smoking cessation or the prevention of alcohol or drug relapse in male smokers who were in early or sustained full remission from alcohol and motivated to make a quit attempt. Alternative approaches for treating this high-risk, dually dependent population are needed.

The use of varenicline to treat nicotine dependence among patients with cancer

BACKGROUND

Continuing to smoke after a cancer diagnosis can adversely influence the prognosis for patients with cancer. However, remarkably few studies have carefully examined the use of first-line FDA-approved medications for nicotine dependence in patients with cancer. This study evaluated the feasibility, safety, and effect on cessation of varenicline for smoking cessation in patients with cancer.

METHODS

Data from 132 treatment-seeking smokers who received 12 weeks of open-label varenicline and five brief behavioral counseling sessions were used to evaluate the feasibility, safety, and impact on cessation of varenicline. The effects of abstinence on cognitive function and affect were also explored.

RESULTS

Of 459 patients screened, 306 were eligible for the study (66.7%) and 132 entered treatment (43.1%). Retention was 84.1% over 12 weeks. The rate of biochemically verified abstinence at week 12 was 40.2%. Expected side effects were reported (e.g. sleep problems, nausea), but there were no reports of elevated depressed mood, suicidal thoughts, or cardiovascular events. Abstinence was associated with improved cognitive function and reduced negative affect over time (p < 0.05).

CONCLUSIONS

Although many patients with cancer who smoke did not enroll in treatment, the side effect profile of varenicline and its effect on short-term cessation converge with what is seen in the general population. Further, as with the general population, abstinence while taking varenicline may lead to improved cognitive function and reduced negative affect. The present data support the use of varenicline to help patients with cancer to quit smoking.

Sex Differences in Varenicline Efficacy for Smoking Cessation: A Meta-Analysis

INTRODUCTION

Women have lower rates of quitting than men with both bupropion and nicotine replacement. It is unknown whether varenicline demonstrates differential efficacy for men and women. The purpose of this study was to conduct the first comprehensive meta-analysis of clinical trial data examining sex differences in the efficacy of varenicline for smoking cessation.

METHODS

Searching MEDLINE, EMBASE, and PsychINFO, 17 of 43 clinical trials of varenicline for smoking cessation published through December 31, 2014 were low-bias randomized double-blind placebo-controlled trials. Data (n = 6710 smokers, 34% female, n = 16 studies, 96% of available data) was analyzed with Metafor program in R. Outcome endpoints were 7-day point-prevalence (PP) and continuous-abstinence (CA) at week 12 (end of treatment), week 24 (6-month follow-up), and week 52 (12-month follow-up).

RESULTS

Using placebo, women were less likely than men to quit (PP-12, CA-24; P < .05 for sex). Using varenicline, similar rates of abstinence for men and women were demonstrated for all six outcomes (eg, PP-12 abstinence rates were 53% in both women and men). Varenicline versus placebo outcomes demonstrated that varenicline was more effective for women for short and intermediate outcomes (PP-12, CA-12, CA-24; P < .05 sex × medication interaction). For end-of-treatment PP, varenicline was 46% more effective for women. For continuous abstinence, varenicline was 34% (CA-12) and 31% (CA-24) more effective for women.

CONCLUSIONS

Unlike other smoking cessation medications, varenicline demonstrated greater efficacy among women smokers for short and immediate-term outcomes and equal efficacy for 1-year outcomes. Varenicline may be particularly useful for reducing the sex disparity typically seen in rates of smoking cessation.

IMPLICATIONS

Varenicline is currently the most effective FDA-approved smoking cessation medication and this is the first demonstration that women compared with men have a preferred therapeutic response for a smoking cessation medication when considering short-term outcomes. Importantly, this is also the first demonstration that women have similar rates of quitting to men when considering longer-term, 1-year outcomes.

Sleep Disturbance During Smoking Cessation: Withdrawal or Side Effect of Treatment?

INTRODUCTION

The nicotine-metabolite ratio (NMR) predicts treatment response and is related to treatment side effect severity. Sleep disturbance may be one important side effect, but understanding sleep disturbance effects on smoking cessation is complicated by the fact that nicotine withdrawal also produces sleep disturbance.

AIMS

To evaluate the effects of withdrawal and treatment side effects on sleep disturbance.

METHODS

This is a secondary analysis of data from a clinical trial (Lerman et al., 2015) of 1,136 smokers randomised to placebo (n = 363), transdermal nicotine (TN; n = 381), or varenicline (n = 392) and stratified based on NMR (559 slow metabolisers; 577 normal metabolisers). Sleep disturbance was assessed at baseline and at 1-week following the target quit date (TQD). We also examined whether sleep disturbance predicted 7-day point-prevalence abstinence at end-of-treatment (EOT).

RESULTS

The varenicline and TN groups exhibited greater increases in sleep disturbance (vs. placebo; treatment × time interaction; p = 0.005), particularly among those who quit smoking at 1-week post-TQD. There was a main effect of NMR (p = 0.04), but no interactions with treatment. TN and varenicline attenuated withdrawal symptoms unrelated to sleep (vs. placebo). Greater baseline sleep disturbance predicted relapse at EOT (p = 0.004).

CONCLUSIONS

Existing treatments may not mitigate withdrawal-related sleep disturbance and adjunctive treatments that target sleep disturbance may improve abstinence rates.

Varenicline Effects on Smoking, Cognition, and Psychiatric Symptoms in Schizophrenia: A Double-Blind Randomized Trial

Schizophrenic patients have a high rate of smoking and cognitive deficits which may be related to a decreased number or responsiveness of nicotinic receptors in their brains. Varenicline is a partial nicotinic agonist which is effective as an antismoking drug in cigarette smokers, although concerns have been raised about potential psychiatric side-effects. We conducted a double-blind placebo controlled study in 87 schizophrenic smokers to evaluate the effects of varenicline (2 mg/day) on measures of smoking, cognition, psychiatric symptoms, and side-effects in schizophrenic patients who were cigarette smokers. Varenicline significantly decreased cotinine levels (P<0.001), and other objective and subjective measures of smoking (P < .01), and responses on a smoking urges scale (P = .02), more than placebo. Varenicline did not improve scores on a cognitive battery designed to test the effect of drugs on cognitive performance in schizophrenia (the MATRICS battery), either in overall MATRICS battery Composite or individual Domain scores, more than placebo. There were no significant differences between varenicline vs. placebo effects on total symptom scores on psychiatric rating scales, PANSS, SANS, or Calgary Depression scales, and there were no significant drug effects in any of these scales sub-scores when we used Benjamin-Hochberg corrected significance levels (α = .05). Varenicline patients did not show greater side-effects than placebo treated patients at any time point when controlled for baseline side-effect scores. Our study supports the use of varenicline as a safe drug for smoking reduction in schizophrenia but not as a cognitive enhancer.

TRIAL REGISTRATION

ClinicalTrials.gov 00802919.

Existing and Future Drugs for the Treatment of the Dark Side of Addiction

The identification of a heuristic framework for the stages of the addiction cycle that are linked to neurocircuitry changes in pathophysiology includes the binge/intoxication stage, the withdrawal/negative affect stage, and the preoccupation/anticipation (craving) stage, which represent neuroadaptations in three neurocircuits (basal ganglia, extended amygdala, and frontal cortex, respectively). The identification of excellent and validated animal models, the development of human laboratory models, and an enormous surge in our understanding of neurocircuitry and neuropharmacological mechanisms have provided a revisionist view of addiction that emphasizes the loss of brain reward function and gain of stress function that drive negative reinforcement (the dark side of addiction) as a key to compulsive drug seeking. Reversing the dark side of addiction not only explains much of the existing successful pharmacotherapies for addiction but also points to vast new opportunities for future medications to alleviate this major source of human suffering.

Low Carbohydrate and Moderately Fat-Reduced Diets Similarly Affected Early Weight Gain in Varenicline-Treated Overweight or Obese Smokers

INTRODUCTION

Weight gain is common when stopping smoking. This study compared the effect of advising smokers to follow a diet low in carbohydrates versus a usual fat-reduced diet on weight gain and nicotine withdrawal.

METHODS

In a randomized clinical trial, 122 men and women smokers with body mass index 25-40kg/m(2) were assigned low-carbohydrate versus moderately fat-reduced diets. Within a week thereafter all participants started treatment with a 12-week course of varenicline 10 days prior to the target quit date. Brief dietary and motivational counseling was given at all visits. Self-reported abstinence was validated.

RESULTS

Protein intake in the low-carbohydrate versus fat-reduced diets was 26.4% of total energy versus 20.0%, fat 38.2% versus 30.1%, and carbohydrates 29.0% versus 41.7% (all P < .001). Mean weight changes for the low-carbohydrate versus fat-reduced groups were -1.2 (SD 2.2) versus -0.5 (SD 2.0) kg, -0.2 (SD 3.3) versus 0.5 (SD 2.6) kg, and 2.2 (SD 4.5) versus 2.1 (SD 3.9) kg at 4, 12, and 24 weeks after the target quit date, respectively (not statistically significant). Smoking abstinence rates did not differ between diets. In the combined groups, point prevalence abstinence rates were 71.0% at 12 weeks and 46.3% at 24 weeks. The Minnesota Nicotine Withdrawal Symptoms score was lower in the fat-reduced group compared with the low-carbohydrate group at weeks 4 and 12.

CONCLUSIONS

In overweight or obese smokers using varenicline a low-carbohydrate diet was no better than a fat-reduced diet in reducing weight gain but may result in more severe nicotine withdrawal symptoms. Compared to previous studies, cessation rates with varenicline were not impaired by dietary counseling.

IMPLICATIONS

The study implies that a popular low-carbohydrate diet does not result in greater weight loss than a moderately fat-reduced diet in overweight and obese smokers who are attempting to quit smoking with the aid of varenicline. Dietary counseling combined with varenicline treatment did not appear to unfavorably influence quit rates compared to previous studies in smokers not selected for overweight or obesity. Notably, the withdrawal symptoms score was lower in the fat-reduced dietary group than the low-carbohydrate group, suggesting a venue for further study.

Predicted Impact of Nicotine Reduction on Smokers with Affective Disorders

OBJECTIVES

In 2009 the FDA acquired the authority to reduce the nicotine content in cigarettes if appropriate for public health, prompting research to evaluate the implications of this policy scientifically. Studies in non-psychiatric populations show that reducing the nicotine content of cigarettes to non-addictive levels reduces smoking rates and nicotine dependence. However, few studies have examined this hypothesis in vulnerable populations.

METHODS

In this narrative review we examined the extant literature on the effects of nicotine reduction or cessation on symptoms of withdrawal, as well as psychiatric symptoms, among those with affective disorders.

RESULTS

Following initial withdrawal from nicotine, smokers with affective disorders experience more severe mood disruption than smokers without these disorders. Use of very low nicotine content (VLNC) cigarettes during abstinence may help mitigate the mood-disrupting effects of initial abstinence. Once the initial effects of nicotine withdrawal on mood have passed, longer-term abstinence is associated with psychiatric improvement rather than worsening.

CONCLUSIONS

These findings suggest that if a national nicotine reduction policy were to be implemented, smokers with affective disorders would need additional support to overcome initial withdrawal but that long-term outcomes would likely be positive.

Varenicline and risk of psychiatric conditions, suicidal behaviour, criminal offending, and transport accidents and offences: population based cohort study

OBJECTIVE

To examine associations between varenicline and the incidence of a range of adverse outcomes.

DESIGN

Population based cohort study using within person analyses to control for confounding by indication.

SETTING

Whole population of Sweden.

PARTICIPANTS

7,917,436 people aged 15 and over, of whom 69,757 were treated with varenicline between 2006 and 2009.

MAIN OUTCOME MEASURES

Incidence of new psychiatric conditions, suicidal behaviour, suspected and convicted criminal offending, transport accidents, and suspected and convicted traffic offences.

RESULTS

In the whole population, 337,393 new psychiatric conditions were diagnosed during follow-up. In addition, 507,823 suspected and 338,608 convicted crimes, 40,595 suicidal events, 124,445 transport accidents, and 99,895 suspected and 57,068 convicted traffic crimes were recorded. Within person analyses showed that varenicline was not associated with significant hazards of suicidal behaviour, criminal offending, transport accidents, traffic offences, or psychoses. However, varenicline was associated with a small increase in the risk of anxiety conditions (hazard ratio 1.23, 95% confidence interval 1.01 to 1.51) and mood conditions (1.31, 1.06 to 1.63), which was only seen in people with pre-existing psychiatric disorders.

CONCLUSIONS

Concerns that varenicline is associated with an increased risk of many adverse outcomes, including suicidality and accidents, are not supported in this observational study. The small increase in risk of two psychiatric conditions in people with pre-existing psychiatric disorders needs to be confirmed using other research designs.

Varenicline as a Cause of Suicidal Outcomes

OBJECTIVE

Postmarketing analyses and case reports have associated varenicline use with suicidal behaviors. This article reviews postmarketing analyses, case reports, clinical trials, uncontrolled observational studies, controlled observational studies, and studies in smokers with psychiatric problems that have tested this association.

METHOD

The author searched the literature for relevant reports via computer and other searches to undertake a qualitative, systematic review.

RESULTS

Two pooled analyses of 10 and 17 placebo-controlled trials failed to find more suicidal outcomes in the varenicline condition. Seven large uncontrolled observational studies reported low rates of suicide outcomes in varenicline users (<0.1%), and 1 study reported a higher rate (6%). Five large controlled observational studies did not find more suicide outcomes in varenicline users than in those using prescribed bupropion or over-the-counter nicotine medications. Small placebo-controlled trials and observational studies of smokers with current psychiatric problems did not find varenicline was associated with suicidal outcomes.

CONCLUSIONS

Among the more valid study designs (pooled analyses of placebo controlled trials or large controlled observational studies), there is consistent evidence that varenicline either does not cause increased suicide outcomes, or if it does, the effect is very small. Warnings to consumers and clinicians should reflect, not just the results of postmarketing studies, but the results of the more valid research designs.

Translational Research on Nicotine Dependence

Nicotine dependence is a chronic, relapsing disorder with complex biological mechanisms underlying the motivational basis for this behavior. Although more than 70 % of current smokers express a desire to quit, most relapse within one year, underscoring the need for novel treatments. A key focus of translational research models addressing nicotine dependence has been on cross-validation of human and animal models in order to improve the predictive value of medication screening paradigms. In this chapter, we review several lines of research highlighting the utility of cross-validation models in elucidating the biological underpinnings of nicotine reward and reinforcement, identifying factors which may influence individual response to treatment, and facilitating rapid translation of findings to practice.

Tobacco use and cessation for cancer survivors: an overview for clinicians

Approximately 30% of all cancer deaths in the United States are caused by tobacco use and smoking. Cancers of eighteen sites have been causally linked to smoking, the most common of which are the lung, head and neck, bladder, and esophagus. While quit rates and quit attempt rates are relatively high shortly after a cancer diagnosis, the recidivism rates are also high. Therefore, screening, treating, and preventing relapse to tobacco use is imperative among patients with and survivors of cancer. To date, research has consistently shown that a combination of pharmacologic and behavioral interventions is needed to achieve the highest smoking cessation rates, with a recent emphasis on individualized treatment as a most promising approach. Challenges in health care systems, including the lack of appropriate resources and provider training, have slowed the progress in addition to important clinical considerations relevant to the treatment of tobacco dependence (eg, a high degree of comorbidity with psychiatric disorders and other substance use disorders). However, continued tobacco use has been shown to limit the effectiveness of major cancer treatments and to increase the risk of complications and of developing secondary cancers. The authors recommend that oncology providers screen all patients for tobacco use and refer users to specialized treatment when available. Alternatively, oncology clinicians can provide basic advice on tobacco use cessation and pharmacotherapy and/or referral to outside resources (eg, quitlines). Herein, the authors summarize the current knowledge on tobacco use and its treatment, with a focus on the related available evidence for patients with and survivors of cancer.

Efficacy of Resistance Training as an Aid to Smoking Cessation: Rationale and Design of the Strength To Quit Study

Despite recent declines in the rates of cigarette smoking, smoking remains prevalent among individuals with lower income, less education, and those with mental illness or HIV. Exercise is promoted as an aid to smoking cessation; however, the evidence for this recommendation is equivocal. To date, the majority of studies have only examined aerobic exercise; there is a poor understanding of the mechanisms of action; and there is an under-representation of male smokers. The goal of this trial is to produce new data that will help to address each of these gaps. A total of 206 male and female smokers will receive a brief smoking cessation education session prior to being randomized into a 12-week Resistance Training (RT) or Wellness Contact Control group. Both groups will have the option of using nicotine replacement therapy (NRT), and both will meet on-site twice per week during the 12-week program (24 total sessions). Follow-up assessments will occur at the end of the 12-weeks (3-month), and at a 6-month and 12-month (post-randomization) visit. Participants will not receive any additional smoking cessation treatment during follow-up; however, the RT group will receive a 9-month membership to a fitness center to encourage continued resistance training as a way to maintain cessation, and attendance will be tracked. The primary outcome is salivary-cotinine-verified 7-Day Point Prevalence Abstinence (PPA) at the 3-month assessment, and at the 6 and 12-month follow-ups. Secondary outcomes include effects of resistance training on nicotine withdrawal symptoms, indicators of mental health, and markers of disease risk.

Involvement of neuronal β2 subunit-containing nicotinic acetylcholine receptors in nicotine reward and withdrawal: implications for pharmacotherapies

WHAT IS KNOWN AND OBJECTIVE

Tobacco smoking remains a major health problem. Nicotine binds to nicotinic acetylcholine receptors (nAChRs), which can cause addiction and withdrawal symptoms upon cessation of nicotine administration. Pharmacotherapies for nicotine addiction target brain alterations that underlie withdrawal symptoms. This review will delineate the involvement of the β2 subunit of neuronal nAChRs in nicotine reward and in generating withdrawal symptoms to better understand the efficacy of smoking cessation pharmacotherapies.

COMMENT

Chronic nicotine desensitizes and upregulates β2 subunit-containing nAChRs, and the prolonged upregulation of receptors may underlie symptoms of withdrawal. Experimental research has demonstrated that the β2 subunit of neuronal nAChRs is necessary for generating nicotine reward and withdrawal symptoms.

WHAT IS NEW AND CONCLUSION

Smoking cessation pharmacotherapies act on β2 subunit-containing nAChRs to reduce nicotine reward and withdrawal symptom severity.

Predictors of lapse and relapse to smoking in successful quitters in a varenicline post hoc analysis in Japanese smokers

BACKGROUND

The efficacy of the smoking-cessation agent varenicline has been reported in Asian smokers; however, few studies have investigated factors that contribute to lapse and relapse.

OBJECTIVE

This post hoc analysis aimed to identify predictors of smoking lapse and relapse.

METHODS

This was a post-hoc analysis based on a double-blind, placebo-controlled, randomized, parallel-group study in which Japanese smokers (aged 20-75 years) who smoked ≥ 10 cigarettes/day and were motivated to quit were randomized to receive varenicline (0.25 mg twice daily [BID], 0.5 mg BID, 1 mg BID) or placebo for 12 weeks followed by a 40-week non-treatment follow-up. For inclusion in this analysis, participants must have been nicotine dependent (Tobacco Dependence Screener score ≥ 5) and must have successfully quit smoking continuously for 4 weeks (weeks 9-12). Lapse was defined by answering yes to ≥ 1 question in the Nicotine Use Inventory. Relapse was defined by participants having smoked for ≥ 7 days during follow-up measured by the Nicotine Use Inventory.

RESULTS

Of the 619 randomized individuals, 515 had a Tobacco Dependence Screener score of ≥ 5, and 277 quit smoking continuously from weeks 9 to 12. Approximately 75% were male, with a mean (SD) BMI of 23.0 (3.0) kg/m(2). Maximum length of continuous abstinence (CA) during treatment and age (both P < 0.0001) were significant predictors of lapse. Maximum CA (P < 0.0001), age (P = 0.0002), Minnesota Nicotine Withdrawal Scale (MNWS) score for urge to smoke (P = 0.0019), and having made ≥ 1 serious quit attempt (P = 0.0063) were significant predictors of relapse. For participants with a maximum CA of 4 to 6 weeks versus those with a maximum CA of 10 to 11 weeks, the ORs for lapse and relapse were 4.649 (95% CI, 2.071-10.434) and 3.337 (95% CI, 1.538-7.239), respectively. In participants aged 21-34 years versus those aged 47-72 years, the ORs for lapse and relapse were 3.453 (95% CI 1.851, 6.441) and 3.442 (95% CI 1.795, 6.597), respectively. Participants with a MNWS urge to smoke score of 2 to 4 versus 0 had an OR for relapse of 3.175 (95% CI, 1.166-8.644). Participants having made ≥ 1 versus no serious quit attempts had an OR for relapse of 2.108 (95% CI, 1.168-3.805).

CONCLUSION

Shorter maximum CA and younger age at quit attempt were associated with increased risk of lapse and relapse. Higher MNWS urge to smoke score and having made ≥ 1 serious quit attempt were associated with increased relapse risk. ClinicalTrials.gov identifier: NCT00139750.

An efficient early phase 2 procedure to screen medications for efficacy in smoking cessation

RATIONALE

Initial screening of new medications for potential efficacy (i.e., Food and Drug Administration (FDA) early phase 2), such as in aiding smoking cessation, should be efficient in identifying which drugs do, or do not, warrant more extensive (and expensive) clinical testing.

OBJECTIVES

This focused review outlines our research on development, evaluation, and validation of an efficient crossover procedure for sensitivity in detecting medication efficacy for smoking cessation. First-line FDA-approved medications of nicotine patch, varenicline, and bupropion were tested as model drugs, in three separate placebo-controlled studies. We also tested specificity of our procedure in identifying a drug that lacks efficacy, using modafinil.

RESULTS

This crossover procedure showed sensitivity (increased days of abstinence) during week-long "practice" quit attempts with each of the active cessation medications (positive controls) versus placebo, but not with modafinil (negative control) versus placebo, as hypothesized. Sensitivity to medication efficacy signal was observed only in smokers high in intrinsic quit motivation (i.e., already preparing to quit soon) and not smokers low in intrinsic quit motivation, even if monetarily reinforced for abstinence (i.e., given extrinsic motivation).

CONCLUSIONS

A crossover procedure requiring less time and fewer subjects than formal trials may provide an efficient strategy for a go/no-go decision whether to advance to subsequent phase 2 randomized clinical trials with a novel drug. Future research is needed to replicate our results and evaluate this procedure with novel compounds, identify factors that may limit its utility, and evaluate its applicability to testing efficacy of compounds for treating other forms of addiction.

Cognition as a therapeutic target in late-life depression: potential for nicotinic therapeutics

Depression is associated with impairments to cognition and brain function at any age, but such impairments in the elderly are particularly problematic because of the additional burden of normal cognitive aging and in some cases, structural brain pathology. Individuals with late-life depression exhibit impairments in cognition and brain structural integrity, alongside mood dysfunction. Antidepressant treatment improves symptoms in some but not all patients, and those who benefit may not return to the cognitive and functional level of nondepressed elderly. Thus, for comprehensive treatment of late-life depression, it may be necessary to address both the affective and cognitive deficits. In this review, we propose a model for the treatment of late-life depression in which nicotinic stimulation is used to improve cognitive performance and improve the efficacy of an antidepressant treatment of the syndrome of late-life depression. The cholinergic system is well-established as important to cognition. Although muscarinic stimulation may exacerbate depressive symptoms, nicotinic stimulation may improve cognition and neural functioning without a detriment to mood. While some studies of nicotinic subtype specific receptor agonists have shown promise in improving cognitive performance, less is known regarding how nicotinic receptor stimulation affects cognition in depressed elderly patients. Late-life depression thus represents a new therapeutic target for the development of nicotinic agonist drugs. Parallel treatment of cognitive dysfunction along with medical and psychological approaches to treating mood dysfunction may be necessary to ensure full resolution of depressive illness in aging.