Smoking Cessation Clinical Trial Research Articles

Optimal Serum Cotinine Levels for Distinguishing Cigarette Smokers and Nonsmokers Within Different Racial/Ethnic Groups in the United States Between 1999 and 2004

Cotinine, a metabolite of nicotine, is widely used to distinguish smokers from nonsmokers in epidemiologic studies and smoking-cessation clinical trials. As the magnitude of secondhand smoke exposure declines because of proportionally fewer smokers and more clean-indoor-air regulations, the optimal cotinine cutpoint with which to distinguish smokers from nonsmokers is expected to change. The authors analyzed data on 3,078 smokers and 13,078 nonsmokers from the National Health and Nutrition Examination Survey for 1999-2004. Optimal serum cotinine concentrations for discriminating smokers from nonsmokers were determined using receiver operator characteristic curve analysis. Optimal cotinine cutpoints were 3.08 ng/mL (sensitivity = 96.3%, specificity = 97.4%) and 2.99 ng/mL (sensitivity = 86.5%, specificity = 93.1%) for adults and adolescents, respectively. Among adults, optimal cutpoints differed by race/ethnicity: They were 5.92 ng/mL, 4.85 ng/mL, and 0.84 ng/mL for non-Hispanic blacks, non-Hispanic whites, and Mexican Americans, respectively. Among adolescents, cutpoints were 2.77 ng/mL, 2.95 ng/mL, and 1.18 ng/mL for non-Hispanic blacks, non-Hispanic whites, and Mexican Americans, respectively. Use of the currently accepted cutpoint of 14 ng/mL overestimates the number of nonsmokers in comparison with the proposed new overall cutpoint of 3 ng/mL or the race/ethnicity-specific cutpoints of 1-6 ng/mL.

Effects of a cannabinoid receptor (CB) 1 antagonist AM251 on behavioral sensitization to nicotine in a rat model of novelty-seeking behavior: correlation with hippocampal 5HT

There are marked individual differences in the efficacy of mainstream nicotine cessation agents in preventing relapse. A rat model of novelty-seeking phenotype was reported to have predictive value for psychostimulant taking behavior where locomotor reactivity to novelty is used to rank high (HR, highest 1/3) versus low (LR, lowest 1/3) responsiveness to novelty in outbred rats. We tested the hypothesis that a cannabinoid receptor (CB) 1 antagonist that is in clinical trials for smoking cessation may reverse behaviorally sensitizing effects of nicotine in HRs and repeated nicotine-induced elevations in hippocampal 5HT. Adolescent LRHR rats underwent intermittent behavioral sensitization to nicotine regimen with or without a CB1 receptor antagonist AM251 or bupropion treatment following nicotine training during 1 week of nicotine-free period. Expression of behavioral sensitization to nicotine was assessed in response to a low-dose nicotine challenge. Using the same sensitization regimen and therapeutic treatments, hippocampal 5HT levels were measured via in vivo microdialysis in response to the nicotine challenge. HR but not LR animals showed behavioral sensitization to a low-dose nicotine challenge following intermittent nicotine training and 1 week of injection-free period. AM251 (5 mg/kg, i.p.) but not bupropion administration during injection-free period successfully reversed locomotor sensitization to nicotine challenge in HRs. AM251 treatment also reversed nicotine-induced elevations in extracellular 5HT in the HR hippocampal hilus. These data suggest that CB1 antagonists may prevent locomotor sensitization to nicotine and reverse nicotine-induced elevations in hippocampal 5HT in high novelty seekers.

Light versus heavy smoking among African American men and women

The majority of smoking cessation research has focused on heavy smokers. African Americans (AA) are less likely than the general population to be heavy smokers. Thus, little is known about the smoking and psychosocial characteristics of lighter AA smokers. The present study compared the baseline demographic, smoking, and psychosocial characteristics of light (5–10 cigarettes per day; n = 86) and moderate to heavy (> 10 cigarettes per day; n = 286) AA smokers enrolled in a smoking cessation clinical trial. Results indicated no differences between groups on demographic variables. However, light smokers (LS) were less dependent on smoking, reported more previous quit attempts, and had higher self-efficacy to quit than moderate to heavy smokers (MHS). On a measure of withdrawal, LS reported less pre-quit craving and less difficulty concentrating than MHS. In addition, LS reported lower perceived stress, fewer symptoms of depression, and greater positive affect than AA MHS. These findings highlight important similarities and differences between AA LS and MHS, and have implications for the treatment of AA smokers.

Nicotine abstinence genotyping: assessing the impact on smoking cessation clinical trials

Twin studies document substantial heritability for successful abstinence from smoking. A genome-wide association study has identified markers whose allele frequencies differ with nominal P<0.005 in nicotine-dependent clinical trial participants who were successful vs unsuccessful in abstaining from smoking; many of these results are also supported by data from two additional samples. More study is required to precisely determine the variance in quitting success that can be accounted for by the single-nucleotide polymorphisms that are currently identified and to precisely classify individuals who may display varying degrees of genetic vs environmental effects into quitters or nonquitters. However, the data at hand do allow us to model the effects of genotypic stratification in smoking cessation trials. We identify relationships between the costs of identifying and genotyping prospective trial participants vs the costs of performing the clinical trials. We quantitate the increasing savings that result from genetically stratified designs as recruiting/genotyping costs go down and trial costs increase. This model helps to define the circumstances in which genetically stratified designs may enhance power and reduce costs for smoking cessation clinical trials.

Issues related to implementing a smoking cessation clinical trial for cancer patients

Given high rates of smoking among cancer patients, smoking cessation treatment is crucial; yet limited data exist to guide integration of such trials into the oncologic context. In order to determine the feasibility of conducting smoking cessation clinical trials with cancer patients, screening and baseline data from a large randomized placebo-controlled pharmacotherapy trial were analyzed. Descriptive statistics and regression analyses were used to compare enrollees to decliners, describe program enrollees, and assess correlates of confidence in quitting smoking. Out of 14,514 screened patients, 263 (<2%) were eligible; 43 (16%) refused enrollment. Among the eligible patients, 220 (84%) enrolled. Enrollment barriers included smoking rate, medical history/contraindicated medication, lack of interest, and language. Compared to enrollees, decliners were more likely to have advanced cancer. The trial enrolled a sample of 67 (>30%) African Americans; participants had extensive smoking histories; many were highly nicotine dependent; and participants consumed about seven alcoholic beverages/week on average. Head and neck and breast cancer were the most common tumors. About 52 (25%) reported depressive symptoms. A higher level of confidence to quit smoking was related to lower depression and lower tumor stage. Integrating a smoking cessation clinical trial into the oncologic setting is challenging, yet feasible. Recruitment strategies are needed for patients with advanced disease and specific cancers. Once enrolled, addressing participant's depressive symptoms is critical for promoting cessation.

A brief 7-day estimate of alcohol consumption for use in smoking cessation clinical trials

Accruing evidence of an association between drinking and smoking relapse suggests that it is important to measure alcohol use in smoking cessation studies. However, most studies do not do so, often because of the extra time burden required for these assessments. Data from participants (N=634) in two smoking cessation clinical trials were used to examine the relationship between short and longer periods of monitoring for a number of Timeline Followback (TLFB) drinking metrics at baseline and during treatment. High intercorrelations were found between short (7 and 14 days) and longer (30 and 60 days) time windows for baseline drinking data. Intercorrelations between short (last 7 days of treatment) and longer (entire treatment period) time windows of drinking data during the smoking cessation treatment period were also mostly in the high range. Although total abstinence was significantly overestimated with shorter time windows, for those who were misclassified, percentage of days abstinent was high and percentage of heavy drinking days and number of drinks per drinking day were low during the longer period. Thus, a brief estimate of alcohol use over 7 days at baseline is likely to provide a representative assessment of percentage of days abstinent, percentage of heavy drinking days, and number of drinks per drinking day. To estimate abstinence at baseline and during treatment, however, a more comprehensive period of monitoring may be required.

The Chinese Community Smoking Cessation Project: A Community Sensitive Intervention Trial

This paper describes (1) the design, methods and baseline data of the first smoking cessation clinical trial for Chinese Americans with medical conditions - Chinese Community Smoking Cessation Project (CCSCP); (2) the collaborative process between researchers and the Chinese community; and (3) the barriers and facilitators of implementing the study. CCSCP was a culturally tailored, randomized, smoking cessation trial testing the efficacy of an intensive (physician advice, in-person counseling with nicotine replacement therapy, 5 telephone calls) compared to a minimal (physician advice and self-help manual) intervention. The study applied a community-sensitive research method involving community members in all phases of the research process in San Francisco Bay Area during 2001-2007. CCSCP recruited 464 smokers from health care facilities (79%) located in Chinese neighborhoods and through Chinese language media (21%). Baseline assessments and interventions were conducted in-person using translated and tested questionnaire and intervention materials. The majority of the participants were men (91%) with a mean age of 58.3 years, foreign born (98%), with less than high school education (58%), spoke no English (42%) and in non-skilled or semi-skilled occupations (60%) with <$20,000 household income (51%). Participants smoked regularly on an average 38.6 +/- 17 years, smoked 9.1 +/- 8 cigarettes per day and 85% smoked daily. Cultural tailoring of recruitment methods and intervention design led to successful enrollment and retention of participants, overcoming barriers faced by the participants. Community sensitive collaborative process facilitated implementation of study protocol in community health care settings.

Reliability of internet- versus telephone-administered questionnaires in a diverse sample of smokers.

Background Smoking is more prevalent among lower-income individuals and certain racial/ethnic minorities. Addressing tobacco cessation among diverse populations is an urgent public health priority. As Internet use continues to rise among all segments of the US population, Web-based interventions have enormous potential to reach priority populations. Conducting Web-based smoking cessation research in priority populations requires psychometrically sound measurement instruments. To date, only one published study has examined the psychometric properties of Internet-administered measures commonly used in Web-based cessation trials. However, the sample was homogeneous with regard to race/ethnicity and income. We sought to replicate and extend these findings in a more diverse sample of smokers.Objective The aim was to examine the internal consistency and test-retest reliability of measures commonly used in smoking cessation clinical trials among racial/ethnic minorities and smokers with lower income.Methods Participants were enrolled in a randomized trial of the efficacy of an Internet smoking cessation program between June 2005 and September 2006. Following a baseline telephone assessment and randomization into the parent trial, participants were recruited to the reliability substudy. In phase I of recruitment, all participants in the parent trial were recruited to the substudy; in phase II, all consecutive racial/ethnic minority participants in the parent trial were recruited. Race and ethnicity were assessed via self-report using two standard items from the US Office of Management and Budget. An email was sent 2 days after the telephone assessment with a link to the Internet survey. Measures examined were quit methods, perceived stress, depression, social support, smoking temptations, alcohol use, perceived health status, and income. Internal consistency and test-retest reliability of Internet- versus telephone-administered measures were examined within four strata defined by race/ethnicity (non-Hispanic White, racial/ethnic minority) and annual household income (US $40,000 or less, more than $40,000).Results Of the 442 individuals invited, 319 participated (72% response rate): 52.4% were non-Hispanic White, 22.9% Black, 11.6% Hispanic, 7.8% Asian, 4.4% American Indian / Alaska Native, and 1% Native Hawaiian / Other Pacific Islander. About half (49.4%) reported an annual household income of US $40,000 or less, and 25.7% had a high school degree or less. Test-retest reliability was satisfactory to excellent across all strata for the majority of measures examined: 9 of 12 continuous variables had intraclass correlation coefficients ≥ 0.70, and 10 of 18 binary variables and both ordinal variables had kappa coefficients ≥ 0.70. Test-retest reliability of several quit methods varied across strata.Conclusions Race/ethnicity and income do not affect the psychometric properties of most Internet-administered measures examined. This knowledge adds to the confidence of conducting Web-based smoking cessation research and strengthens the scientific rigor of collecting information via the Internet on racial/ethnic minority and low-income subgroups.Trial registrationclinicaltrials.gov NCT00282009 (parent trial)

Perfil dos fumantes que não buscam tratamento para deixar de fumar, município do Rio de Janeiro

It is essential to understand that not all smokers are equal, and that certain smokers need to be "won" as "potential clients" of an intervention program aimed at addressing their specific needs. Thus, the objective of the article was to compare the profile of smokers recruited for a smoking cessation clinical trial with that of the general smoking population in the city of Rio de Janeiro, in the years 2002-2003. Heterogeneities observed may indicate the need for adopting different recruitment strategies, associated with the existing interventions, to encourage as many and as diverse eligible individuals as possible.

Imputation‐based strategies for clinical trial longitudinal data with nonignorable missing values

Biomedical research is plagued with problems of missing data, especially in clinical trials of medical and behavioral therapies adopting longitudinal design. After a literature review on modeling incomplete longitudinal data based on full-likelihood functions, this paper proposes a set of imputation-based strategies for implementing selection, pattern-mixture, and shared-parameter models for handling intermittent missing values and dropouts that are potentially nonignorable according to various criteria. Within the framework of multiple partial imputation, intermittent missing values are first imputed several times; then, each partially imputed data set is analyzed to deal with dropouts with or without further imputation. Depending on the choice of imputation model or measurement model, there exist various strategies that can be jointly applied to the same set of data to study the effect of treatment or intervention from multi-faceted perspectives. For illustration, the strategies were applied to a data set with continuous repeated measures from a smoking cessation clinical trial.

Role of the Glutamatergic System in Nicotine Dependence

Preclinical research findings in laboratory animals indicate that the glutamatergic system is critically involved in nicotine dependence. In animals, compounds that decrease glutamatergic neurotransmission, such as antagonists at postsynaptic NMDA receptors, antagonists at excitatory postsynaptic metabotropic glutamate (mGlu) 5 receptors, or agonists at inhibitory presynaptic mGlu(2) and mGlu(3) receptors, decreased nicotine self-administration or reinstatement of nicotine-seeking behaviour. These findings suggest that medications that decrease glutamatergic transmission overall may reduce the reinforcing effects of tobacco smoking and prevent relapse to tobacco smoking in humans. Furthermore, compounds that increase glutamate release, such as antagonists at mGlu(2) and mGlu(3) receptors, ameliorated reward deficits associated with nicotine withdrawal in animals, and thus may alleviate the depression-like symptoms associated with nicotine withdrawal in humans. Animal studies also showed that alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainate receptors did not appear to be involved in mediating the primary reinforcing effects of nicotine but that they may be involved in the development of nicotine dependence and withdrawal.Taken together, the preclinical data indicate that different glutamatergic receptors are involved in the mediation of different aspects of nicotine dependence. These findings have implications for the discovery and development of new pharmacotherapies that target the glutamatergic system to aid in smoking cessation. At present, very few clinical studies have addressed the effects of glutamatergic compounds on cigarette smoking. Clinical studies involving compounds that have actions at ionotropic glutamate receptors are briefly discussed in this review and suggest the potential of glutamatergic compounds as pharmacotherapies to aid in smoking cessation. Medications that target mGlu receptors have recently been tested in human phase II trials for various indications; however, the potential of these mGlu compounds as medications for nicotine dependence remains to be evaluated in humans. The preclinical data evaluated in this review indicate that such clinical trials for smoking cessation with mGlu compounds are clearly warranted and may reveal novel treatments for nicotine dependence.

Smoking cessation treatment in community-based substance abuse rehabilitation programs

Nicotine dependence is highly prevalent among drug- and alcohol-dependent patients. A multisite clinical trial of smoking cessation (SC) treatment was performed at outpatient community-based substance abuse rehabilitation programs affiliated with the National Drug Abuse Treatment, Clinical Trials Network. Cigarette smokers ( N = 225) from five methadone maintenance programs and two drug and alcohol dependence treatment programs were randomly assigned in a 2:1 ratio to receive either (1) SC treatment as an adjunct to substance abuse treatment-as-usual (TAU) or (2) substance abuse TAU. Smoking cessation treatment consisted of 1 week of group counseling before the target quit date and 8 weeks of group counseling plus transdermal nicotine patch treatment (21 mg/day for Weeks 1–6 and 14 mg/day for Weeks 7 and 8) after the target quit date. Smoking abstinence rates in SC, 10%–11% during treatment and 5%–6% at the 13- and 26-week follow-up visits, were significantly better than those in TAU during treatment ( p < .01). In addition, SC was associated with significantly greater reductions as compared with TAU in cigarettes smoked per day (75% reduction, p < .001), exhaled carbon monoxide levels ( p < .001), cigarette craving ( p < .05), and nicotine withdrawal ( p < .05). Smoking cessation did not differ from TAU on rates of retention in substance abuse treatment, abstinence from primary substance of abuse, and craving for primary substance of abuse. Compliance with SC treatment, moderate at best, was positively associated with smoking abstinence rates. Smoking cessation treatment resulted in significant reductions in daily smoking and modest smoking abstinence rates without having an adverse impact on substance abuse rehabilitation when given concurrently with outpatient substance abuse treatment. Substance abuse treatment programs should not hesitate to implement SC for established patients.

Pharmacogenomics of Nicotine Dependence and Impact on Smoking Cessation

Pharmacogenomic research into smoking behaviour and smoking cessation holds promise for understanding why people smoke and how we can better help people to quit. As smoking prevalence declines in the United States and Western Europe through social and clinical action, average level of tobacco and nicotine dependence amongst smokers may increase. The place of the pharmacogenomic contribution to understanding residual dependence and how to further lower smoking prevalence may increasingly come to the fore. This review examines the influence of genetic variation on smoking initiation, progression to dependence, and persistent regular smoking (including amount smoked) as well as response to smoking cessation pharmacotherapies. Although research is still at an early stage, a future in which individualised treatment is tailored to genotype now seems possible. However, there are substantial practical, ethical, and social considerations that must be addressed before such research can be translated into clinical practice. Keywords: CYP2A6, CCK gene, polymorphism, 5HT2A, GABA, Smoking Cessation Clinical Trials

Hypothesis testing in functional linear regression models with Neyman's truncation and wavelet thresholding for longitudinal data

Longitudinal data sets in biomedical research often consist of large numbers of repeated measures. In many cases, the trajectories do not look globally linear or polynomial, making it difficult to summarize the data or test hypotheses using standard longitudinal data analysis based on various linear models. An alternative approach is to apply the approaches of functional data analysis, which directly target the continuous nonlinear curves underlying discretely sampled repeated measures. For the purposes of data exploration, many functional data analysis strategies have been developed based on various schemes of smoothing, but fewer options are available for making causal inferences regarding predictor-outcome relationships, a common task seen in hypothesis-driven medical studies. To compare groups of curves, two testing strategies with good power have been proposed for high-dimensional analysis of variance: the Fourier-based adaptive Neyman test and the wavelet-based thresholding test. Using a smoking cessation clinical trial data set, this paper demonstrates how to extend the strategies for hypothesis testing into the framework of functional linear regression models (FLRMs) with continuous functional responses and categorical or continuous scalar predictors. The analysis procedure consists of three steps: first, apply the Fourier or wavelet transform to the original repeated measures; then fit a multivariate linear model in the transformed domain; and finally, test the regression coefficients using either adaptive Neyman or thresholding statistics. Since a FLRM can be viewed as a natural extension of the traditional multiple linear regression model, the development of this model and computational tools should enhance the capacity of medical statistics for longitudinal data.

Achieving high rates of consent for genetic testing among African American smokers

Genetic factors play an important role in smoking behavior. Although African Americans are at disproportionately increased risk for tobacco-related morbidity and mortality, limited attention has been given to genetic investigation of tobacco use in this population. The present study examined consent for genetic testing among African American smokers enrolled in a smoking cessation clinical trial. African American light smokers (</=10 cigarettes/day) enrolled in a smoking cessation study met with study counselors to review consent forms for an adjunct study and responded to a request for genetic analysis related to smoking. Participants completed assessment of demographic, psychosocial, and tobacco-related variables. Of 755 clinical trial participants, 745 (99%) responded to the genetic consent form. Of participants who responded, 620 (83%) provided consent for blood collection for genetic analysis. No significant differences were identified between individuals who consented to genetic analysis and those who denied consent. This study demonstrated the feasibility of obtaining consent for genetic analysis for smoking-related investigation among African American smokers. Findings support the inclusion of African Americans within genetic investigation of tobacco use and treatment.

Validation of a scale for the assessment of food cravings among smokers

Weight gain associated with smoking cessation impedes attempts to quit smoking and may lead to obesity. One factor that might contribute to weight gain is cravings for sweet or rich foods. To date, no reliable measure exists for evaluating these cravings. The purpose of the current study was to validate an assessment of craving for sweet or rich foods for use among smokers. With a sample of 385 smokers enrolled in a clinical trial for smoking cessation, the study examined the factor structure, internal consistency, and convergent and predictive validity of the Questionnaire on Craving for Sweet or Rich Foods (QCSRF). A two-factor model best represented the data. Factor 1 contained six items assessing perceptions about the ability of sweet or rich foods to relieve negative affect and about self-control over eating. Factor 2 contained three items assessing the intensity of cravings. Both factors demonstrated high internal consistency and good convergent and predictive validity. These results suggest the QCSRF is a reliable and valid measure for examining cravings for sweet or rich foods among smokers.

A random‐effects Markov transition model for Poisson‐distributed repeated measures with non‐ignorable missing values

In biomedical research with longitudinal designs, missing values due to intermittent non-response or premature withdrawal are usually 'non-ignorable' in the sense that unobserved values are related to the patterns of missingness. By drawing the framework of a shared-parameter mechanism, the process yielding the repeated count measures and the process yielding missing values can be modelled separately, conditionally on a group of shared parameters. For chronic diseases, Markov transition models can be used to study the transitional features of the pathologic processes. In this paper, Markov Chain Monte Carlo algorithms are developed to fit a random-effects Markov transition model for incomplete count repeated measures, within which random effects are shared by the counting process and the missing-data mechanism. Assuming a Poisson distribution for the count measures, the transition probabilities are estimated using a Poisson regression model. The missingness mechanism is modelled with a multinomial-logit regression to calculate the transition probabilities of the missingness indicators. The method is demonstrated using both simulated data sets and a practical data set from a smoking cessation clinical trial.

CYP2B6 Genotype Alters Abstinence Rates in a Bupropion Smoking Cessation Trial

CYP2B6 is the primary enzyme involved in bupropion (Zyban; GlaxoSmithKline, Research Triangle Park, North Carolina) metabolism. Genetic polymorphisms in CYP2B6, such as CYP2B6*6, can alter bupropion metabolism and may affect bupropion treatment outcome. Subjects participated in a smoking cessation clinical trial of bupropion versus placebo. The main outcome was a 7-day point prevalence abstinence rate measured 10 weeks after the start of treatment (i.e., end of treatment) and at the 6-month follow-up; secondary outcomes were severity of adverse effects, withdrawal, and urge to smoke. Subjects were haplotyped for the CYP2B6*6 variants. Among smokers in the CYP2B6*6 group (CYP2B6*1/*6 or CYP2B6*6/*6 genotype, n = 147, 45% of the population), bupropion produced significantly higher abstinence rates than placebo at the end of treatment (32.5% vs. 14.3%, p = .01) and at the 6-month follow-up (31.2% vs. 12.9%, p = .008). In contrast, bupropion was no more effective than placebo for smokers in the CYP2B6*1 group (CYP2B6*1/*1, n = 179) at the end of treatment (31.0% vs. 31.6%, p = .93) or at the 6-month follow-up (22.0% vs. 21.5%, p = .94). There was a significant genotype by treatment interaction at the end of treatment (odds ratio [OR] = 2.97, confidence interval [CI] = 1.05-8.40, p = .04), which was similar at 6-month follow-up (OR = 2.98, CI = .98-9.06, p = .05). These data suggest that smokers with the CYP2B6*6 genotype have a higher liability to relapse on placebo and that they may be good candidates for bupropion treatment for smoking cessation.

Menthol cigarettes and health risks in Lung Health Study data

Whether menthol cigarettes confer a higher risk of death than plain cigarettes is not known. The Lung Health Study (LHS) enrolled 5,887 adult smokers in a clinical trial of smoking cessation and ipratropium in the prevention of chronic obstructive pulmonary disease. LHS participants have been subjected to surveillance for mortality from all causes for 14 years. We examined these data for differences between self-reported smokers of menthol cigarettes versus plain cigarettes. Using proportional hazards regression methods, we found no differences in hazard ratios for coronary heart disease, cardiovascular disease, lung cancer, or death from any cause. Contrary to expectations about nicotine dependence, we found that users of menthol cigarettes had smoked fewer pack-years at baseline. We found no difference in success at smoking cessation with or without menthol. We conclude that our data contain no evidence that mentholation of cigarettes increases the hazards of smoking.

The effects of nicotine gum and counseling among African American light smokers: a 2 × 2 factorial design

Approximately 50% of African American smokers are light smokers (smoke < or = 10 cigarettes a day). The prevalence of light smoking in the United States is increasing, yet there has not been a single smoking cessation clinical trial targeting light smokers. The purpose of this 2 x 2 factorial, randomized clinical trial was to evaluate the efficacy of nicotine gum (2 mg versus placebo) and counseling (motivational interviewing versus health education) for African American light smokers. Participants were assigned randomly to one of four study arms: 2 mg nicotine gum plus health education (HE); 2 mg nicotine gum plus motivational interviewing (MI); placebo gum plus HE; and placebo gum plus MI. A total of 755 African American light smokers (66% female, mean age = 45) were enrolled at a community health center over a 16-month period. Participants received an 8-week supply of nicotine gum and six counseling sessions during the course of the 26-week study. Biochemical measures included expired carbon monoxide (CO) and serum and salivary cotinine. Seven-day quit rates for nicotine gum were no better than for the placebo group (14.2% versus 11.1%, P = 0.232) at 6 months. However, a counseling effect emerged, with HE performing significantly better than MI (16.7% versus 8.5%, P < 0.001). These results were consistent across outcome time-points (weeks 1, 8, and 26). Results highlight the potential positive impact of directive information and advice-oriented counseling on smoking cessation. Studies are needed to assess other interventions that may further improve quit rates among African American light smokers who are motivated to quit.