Characteristics of selectors of nicotine replacement therapy

Objective: To assess differences in demographic and smoking characteristics between smokers who have and have not used nicotine replacement therapy (NRT). Design: Mail survey of US smokers from a national research panel. Participants: Smokers 18 years and over who returned a survey on smoking (n = 9630). The sample was weighted to match the US smoker population on age and sex. Main outcome measures: Compared smokers who had/had not used NRT in a quit attempt (ever NRT use or over the counter (OTC) NRT use) on: demographic characteristics, nicotine dependence, history of craving and withdrawal, expected difficulty quitting, and self reported history of smoking related medical illness and psychopathology. Results: NRT users (both ever-users and OTC users) were more likely to be older, male, and better educated. They were also heavier smokers, had experienced more craving and withdrawal upon quitting, and scored higher on measures of dependence. These differences were evident among light smokers, and remained even when smoking rate and time to first cigarette were controlled. Conclusion: Smokers who elect to use NRT differ from non-NRT users in ways that predispose them to failure in cessation. Controlling for smoking rate and time to first cigarette does not eliminate these differences, even among light smokers. These differences must be considered when comparing the effectiveness of NRT among samples of smokers who self select their treatment and are likely to bias such outcome comparisons.     

A randomized trial of nicotine replacement therapy in combination with reduced-nicotine cigarettes for smoking cessation

A randomized double-blind, active controlled, parallel group, multi-center phase II clinical trial was conducted to evaluate the efficacy of reduced-nicotine cigarettes as a novel smoking cessation treatment (under Investigational Device Exemption 69,185). The concept for a reduced-nicotine cigarette designed to progressively wean smokers from the smoking habit is based on research demonstrating that successful smoking cessation is not only dependent on withdrawal of nicotine, but also on weaning from the habitual sensory and behavioral reinforcement of smoking. Treatment consisted of Quest brand of cigarettes (Quest 1, 2, and 3), which respectively deliver 0.59+/-0.06, 0.3+/-0.05, and less than 0.05 mg nicotine, either alone or in combination with nicotine replacement therapy (NRT). The primary endpoint was 4 weeks of continuous abstinence (Weeks 7-10), with additional follow-up at 3 and 6 months. Adult men and women smokers (N = 346), motivated to quit, were randomized to one of three treatment groups: Quest plus NRT (NRT pretreatment 2 weeks before, and NRT after the quit date), Quest plus placebo patch, or active control plus NRT (conventional cigarette, followed by NRT after quit date). Results showed that Quest plus NRT was more effective than active control plus NRT in achieving 4 weeks of continuous abstinence (32.8% vs. 21.9%). Quest plus placebo patch yielded an abstinence rate similar to that of the active control plus NRT (16.4% vs. 21.9%). No serious adverse events were attributable to the investigational product. Quest plus NRT offers promise as a new smoking cessation treatment.     

The role of impulsivity on smoking maintenance.

In order to better understand why those higher in impulsivity experience more difficulties during smoking abstinence, the current study examined the possible mechanisms contributing to cigarette smoking relapse. Fifty dependent cigarette smokers completed measures designed to assess craving, tobacco withdrawal severity, and negative affect during 48 hours of nicotine abstinence. Using a series of multilevel models (SAS Proc Mixed Procedure), significant impulsivity x time analyses revealed differences in craving, F(2, 96) = 3.74, p<.05, and anxiety, F(2, 96) = 3.23, p<.05. Simple slopes analyses indicated that heightened trait-impulsivity predicted greater increases in craving and anxiety during a 48-hour abstinence period. These findings suggest that smokers with higher levels of impulsivity may lack the ability to find an accessible and comparable substitute for cigarette smoking during a cessation attempt. This study also highlights the importance of considering individual differences when treating those who wish to quit smoking.     

Pilot study on lower nitrosamine smokeless tobacco products compared with medicinal nicotine.

Smokeless tobacco (ST) products have the potential to be used as a harm reduction method for cigarette smokers. These products can deliver significantly less toxicants than cigarettes, although they are not toxicant free nor harmless. It is important to examine potential health risks and benefits of these products. These two small pilot studies examined the effects of two different ST products (Exalt and Ariva) compared with medicinal nicotine, another potential harm reduction product. Dependent, healthy adult cigarette smokers, who were motivated to quit smoking, underwent 1 week of baseline smoking measurement. They were then asked to quit smoking and were randomly assigned to use either an ST product or a medicinal nicotine lozenge (MNL, Commit) for 2 weeks, then crossed over to use the other product for 2 weeks. In the last week, following the sampling phase, subjects could choose the product they wished to use. Assessments were made repeatedly during baseline cigarette use and throughout the 5 weeks of treatment. Outcome measures included biomarkers for tobacco exposure and subjective, physiological, and behavioral responses. Tobacco-specific carcinogen uptake was greater from Exalt than from the MNL, and was comparable between the MNL and Ariva. Physiological effects and subjective effects on withdrawal and craving were comparable among Exalt, Ariva, and the MNL. Ariva was preferred over the MNL, which was preferred over Exalt. With the exception of medicinal nicotine products, low-nitrosamine ST products have the greatest potential to result in reduced toxicant exposure compared with other combustible reduced exposure products and have promise for reducing individual risk for disease. However, the population effect of marketing of such products as reduced exposure/reduced risk is unknown. The need for further research in this area and regulation of tobacco products is evident.     

Comparison of the effects of a 24-hour nicotine patch and a 16-hour nicotine patch on smoking urges and sleep.

This randomized, open-label, crossover study was conducted to compare the effects of a 24-hr nicotine patch and a 16-hr nicotine patch on morning smoking urges and sleep quality of dependent smokers during a short period of cigarette abstinence. A total of 20 smokers (9 women and 11 men) smoking at least 20 cigarettes/day completed the two smoke-free study periods. For each period, cigarette abstinence started on the first evening and a nicotine patch was applied the next morning (for 16 or 24 hr), after baseline measures; a second patch was applied the next morning, 1 hr before the end of the experimental period. Smoking urges, mood and behavior self-reports, psychomotor performance, and polysomnographic recordings were compared between the two types of nicotine patch according to changes from baseline. Both patches decreased morning smoking urges, although results were significantly superior for the 24-hr patch. Furthermore, the 24-hr patch was more effective than the 16-hr patch in reducing the positive reinforcing dimension of smoking urges. Regarding polysomnographic recordings, the proportion of slow wave sleep was significantly increased from baseline with the 24-hr patch compared with the 16-hr patch. As for psychomotor performance measured through the critical flicker fusion test, significant improvement in morning alertness was observed in the 24-hr patch group. In conclusion, the 24-hr nicotine patch formulation is more effective than the 16-hr formulation in alleviating morning smoking urges and more specifically the positive reinforcing factor. The present findings do not support the idea that nicotine delivery during bedtime might disturb sleep, but rather it improves restorative sleep and postwaking arousal.     

Smokers' interest in using nicotine replacement to aid smoking reduction.

In recent years the public health community has considered the risks and benefits of encouraging smokers to reduce their smoking, perhaps with the aid of nicotine replacement therapy (NRT). Little is known, however, about whether smokers themselves are interested in smoking reduction; whether they see reduction as an endpoint, or primarily as a route to cessation; or whether they are receptive to the notion of using NRT to achieve reduction. We conducted a population-based national telephone survey of 1,000 current daily cigarette smokers (499 male, 501 female). Most smokers (57%) reported previously trying to reduce their smoking, and many (26%) said that they plan to reduce within the next year. Almost half of those planning to quit in the next 12 months (44%) preferred to quit via gradual cessation and most (68%) indicated that they would consider using a reduction product or medication. Respondents reported that they would prefer a product with a cessation endpoint rather than a reduction endpoint (63% vs. 21%). Interest in reduction was highest among smokers who were less interested in quitting and among heavier smokers. We conclude that many smokers are interested in gradually reducing prior to quitting and that promoting reduction is unlikely to undermine motivation to quit smoking.     

Anxiety sensitivity and perceived control over anxiety-related events: associations with smoking outcome expectancies and perceived cessation barriers among daily smokers.

The present investigation examined the extent to which the cognitive factors of anxiety sensitivity (AS) and perceived control over anxiety-related events are independently related to smoking outcome expectancies and perceived barriers to quitting. Participants were 125 community-recruited adult, daily smokers. Consistent with hypotheses, AS and perceived control over anxiety-related events independently and significantly predicted smokers' expectancies for negative affect reduction from smoking, whereas only AS predicted expectancies for negative personal consequences from smoking. Also as hypothesized, AS and perceived control over anxiety-related events each independently and significantly predicted level of general perceived barriers to quitting smoking. All of the observed significant effects were evident above and beyond the variance accounted for by gender, alcohol consumption, number of cigarettes smoked per day, and negative affectivity. Together, these findings further the literature on the relation between anxiety-relevant cognitive factors and psychological smoking processes.     

The relationship between cigarette use, nicotine dependence, and craving in laboratory volunteers.

Data from epidemiological studies suggest that individual differences in cigarettes per day (CPD) and duration of smoking account for only a small portion of the variance in Diagnostic and Statistical Manual of Mental Disorders (4th ed.) (DSM-IV) nicotine dependence. However, DSM-IV may be an insensitive measure of nicotine dependence; other measures might better reflect the true nature of the relationship between use and dependence. This paper describes the relationship between cigarettes per day (CPD) and years smoking and the severity of nicotine dependence as measured by the Nicotine Dependence Syndrome Scale (NDSS). Furthermore, we assessed the validity of individual differences in nicotine dependence by determining whether they related to cue-evoked craving during abstinence. Data were pooled from five laboratory studies of 489 regular (i.e., 15+ CPD) smokers. In contrast to previously reported data demonstrating a relatively strong relationship between CPD and dependence in chippers (Shiffman & Sayette, 2005), CPD and years smoking accounted for a statistically significant, but small (<6%), portion of the variance in nicotine dependence in daily smokers. Individual differences in both CPD and years smoking had little or no relationship with craving. However, the magnitude of craving was significantly related to the degree of nicotine dependence even after controlling for use variables and excluding craving-related items on the NDSS. These data suggest that among moderate to heavy daily smokers, meaningful individual differences in nicotine dependence are observed independent of differences in current daily cigarette consumption and duration of smoking. Further research into the sources of this variance is critical to understanding the process of and risk for nicotine dependence.     

Real-time craving and mood assessments before and after smoking.

This study explored some quandaries concerning craving and mood as motivators to smoke. Craving and negative mood have long been associated with day-to-day smoking as two of the primary motivational forces behind the maintenance of the behavior, as well as significant barriers in smokers' attempts to quit. Craving remains a clinically relevant phenomenon, with most smokers describing craving as a troublesome problem when quitting. Smokers' self-reports of negative mood, as an antecedent for smoking, are so robustly reported that many models of nicotine dependence have incorporated a critical role for negative mood in maintaining smoking behavior. However, several naturalistic studies that collected mood ratings with hand held computers from smokers in real time, just before smoking a cigarette, have provided scant evidence that negative mood plays a major role in motivation to smoke. No study to date has examined craving and mood data as a consequence of smoking, that is, collecting the same data immediately after smoking. This study used personal digital assistants (PDAs) to collect craving and mood data immediately before smoking, immediately after smoking, and at random times of day. Nontreatment seeking smokers (N = 72) carried a PDA for an average of 10 days while they recorded their smoking behavior. Results showed that craving and negative mood ratings were lowest immediately after smoking compared with immediately before smoking and at random times of day. These findings suggest that smokers may be at least partially motivated to smoke to lower their craving and improve their mood states.     

Transdermal nicotine use in postmenopausal women: does the treatment efficacy differ in women using and not using hormone replacement therapy?

This study of postmenopausal female smokers (N = 94) asked: During short-term smoking abstinence, do the beneficial effects of transdermal nicotine replacement therapy (NRT) on acute symptomatology (i.e., withdrawal, cigarette craving, smoking urges, mood, depressive symptoms, motor speed, and reaction time) differ in women who use and do not use hormone replacement therapy (HRT)? Participants were recruited according to HRT and non-HRT use (self-selecting), then randomized within strata to active nicotine or placebo nicotine patch. After 1 baseline week of smoking, participants quit smoking for 2 weeks. Women received cessation counseling and were monitored for abstinence. Dependent measures were collected during five clinic visits. Two-way analysis of covariance (ANCOVA) were run on change scores for dependent variables, with nicotine patch group (active/placebo) and HRT group (HRT/non-HRT) as independent variables and age as a covariate. No interactions were found between HRT and patch condition, but both showed specific effects. During the first abstinent week, women on active nicotine patch (compared with placebo) experienced less severe withdrawal, greater reductions in cigarette cravings, and lower (more favorable) Factor 1 scores on the Questionnaire of Smoking Urges. During the second abstinent week, women using HRT (compared with the non-HRT group) exhibited better mood (Profile of Mood States scores) and less depression (Beck Depression Inventory scores). These results suggest the following: First, the efficacy of transdermal nicotine replacement is not adversely modified by women's HRT use; second, ovarian hormones might influence women's responses to smoking cessation, and thus should be considered in developing effective strategies for women to quit smoking.     

Treating smokers before the quit date: can nicotine patches and denicotinized cigarettes reduce cravings?

The present study investigated whether treatment with the combination of denicotinized cigarettes and 21-mg nicotine patch for 2 weeks before a designated quit date could lessen cravings for smoking, thereby helping smokers abstain from smoking. The study was a randomized controlled clinical trial conducted at Roswell Park Cancer Institute, Buffalo, New York, in 2004 and 2005. Patients included 98 adult heavy smokers (using 20 or more cigarettes/day). Half of the subjects received 2 weeks of combination of denicotinized cigarettes (Quest 3) and 21-mg nicotine patch for 2 weeks before the quit date. The remaining smokers were switched to light cigarettes (Quest 1) during the 2 weeks before the quit date. After the quit date, all subjects received counseling for smoking cessation and were provided nicotine patches for up to 8 weeks after the quit date. Self-reported cravings for smoking, withdrawal symptoms, and smoking abstinence were measured at predetermined intervals using phone-based surveys and in clinical visits. The group that used denicotinized cigarettes and nicotine patch before quitting reported less frequent and less intense cravings for cigarettes in the 2 weeks before and after the designated quit date. Self-reported withdrawal symptoms and quit rates did not differ significantly between the groups. The use of a denicotinized cigarette combined with the nicotine patch appears to lessen cravings to smoke in the immediate postcessation period. A larger, better-powered study is needed to test if this treatment combination has merit for increasing quit rates.     

Industry research on the use and effects of levulinic acid: a case study in cigarette additives.

Public health officials and tobacco researchers have raised concerns about the possible contributions of additives to the toxicity of cigarettes. However, little attention has been given to the process whereby additives promote initiation and addiction. Levulinic acid is a known cigarette additive. Review of internal tobacco industry documents indicates that levulinic acid was used to increase nicotine yields while enhancing perceptions of smoothness and mildness. Levulinic acid reduces the pH of cigarette smoke and desensitizes the upper respiratory tract, increasing the potential for cigarette smoke to be inhaled deeper into the lungs. Levulinic acid also may enhance the binding of nicotine to neurons that ordinarily would be unresponsive to nicotine. These findings held particular interest in the internal development of ultralight and so-called reduced-exposure cigarette prototypes. Industry studies found significantly increased peak plasma nicotine levels in smokers of ultralight cigarettes following addition of levulinic acid. Further, internal studies observed changes in mainstream and sidestream smoke composition that may present increased health risks. The use of levulinic acid illustrates the need for regulatory authority over tobacco products as well as better understanding of the role of additives in cigarettes and other tobacco products.     

A psychometric evaluation of cigarette stimuli used in a cue reactivity study.

Laboratory studies have demonstrated that cigarette smokers react with significant subjective and autonomic responses (e.g., increased craving and increased heart rate) in the presence of stimuli associated with smoking. Although cue reactivity effects are typically robust, a number of methodological considerations make interpretation and design of cue reactivity studies problematic. Previous research has paid scant attention to the psychometric properties of the cigarette cues presented, and standard cues would enhance comparison and synthesis of studies. In the present study, we evaluated 12 cigarette photos (compared with positive, negative, and neutral photos), used in a separate study, for their ability to evoke self-report of craving in both nicotine-deprived and nondeprived smokers. These photos performed as expected, with cigarette pictures evoking significantly higher craving than neutral pictures and deprived smokers showing a trend toward higher craving than nondeprived smokers. The cigarette picture set was evaluated for internal consistency (Cronbach's alpha = .97) as a 12-item scale and further reduced to multiple 2-item scales with reliability estimates ranging from .70 to .93. A cluster analysis of all pictures showed that, when rated for craving, cigarette pictures clustered together, indicating they had distinct properties compared with positive, negative, and neutral pictures. Effect sizes were calculated for each cigarette picture in both deprived and nondeprived smokers. The craving effect sizes ranged from .57 to .98 for nondeprived smokers, and from .61 to .99 for deprived smokers. The analyses suggest these cigarette pictures have excellent psychometric properties for use in future cue reactivity studies.     

Determinants of salivary cotinine levels among current smokers in Mexico.

The present study describes salivary cotinine levels and their relationship to cigarettes smoked per day in Mexican smokers. Using a sampling strategy based on the number of cigarettes per day, we recruited 1,222 smokers from Mexico City and the state of Morelos in Mexico during 1999. Smoking behaviors and other factors known to affect nicotine intake and cotinine level were identified in an interview using a standardized questionnaire. Salivary cotinine was measured by capillary gas chromatography with nitrogen-phosphorus detection. We used generalized additive models to describe the relationship between salivary cotinine levels and variables of interest. The mean age of the population was 39.7 years (SD=15.6 years), with a mean cotinine level of 194.7 ng/ml (SD=134.8; range=10.1-767). Participants smoked a mean of 15.5 cigarettes per day (SD=11.3). Salivary cotinine and cigarettes smoked per day were positively related, although the association was not linear, flattening above 20 cigarettes per day. After adjusting for cigarettes per day, we found that significant predictors of cotinine levels included age, body mass index, cigarette producer, and smoking behavior variables. These results may have implications for dosing with nicotine medications to aid smoking cessation in Mexican smokers and suggest that whether the cigarette is labeled light or regular has no relationship to nicotine dose from smoking cigarettes.     

The influence of gender, race, and menthol content on tobacco exposure measures.

Research has suggested that race, gender, and menthol cigarette use influence tobacco-smoke exposure measures and smoking-related disease risk. For example, a high proportion of Black smokers prefer menthol cigarettes and, despite smoking fewer cigarettes per day (CPD) than do Whites, tend to have higher cotinine levels. Additionally, Black males are more at risk for smoking-related lung cancer. High cotinine levels and smoking menthol cigarettes may lead to higher toxin intake, which contributes to increased disease risk. We explored the relationship between tobacco exposure variables (i.e., cotinine, CPD, carbon monoxide [CO], nicotine content, and nicotine dependence) with respect to race, gender, and menthol content in a sample of 307 smokers recruited from the greater Boston area to participate in a smoking cessation treatment trial. The pattern of correlations between tobacco exposure measures and cotinine showed a consistently positive correlation between cotinine and CO in all smokers and a correlation between cotinine and CPD in those who smoked nonmenthol cigarettes. Cotinine and CPD correlations varied by gender and race among menthol cigarette smokers. Consistently, we found a significant gender x race x menthol interaction on salivary cotinine level as well as cotinine/CPD ratio. These findings suggest that the relationship between number of cigarettes consumed and salivary cotinine is more complex than previously believed. It is not sufficient to look at race alone; researchers and clinicians need to look at race and gender concurrently, as well as type of cigarette consumed.     

Tobacco craving predicts lapse to smoking among adolescent smokers in cessation treatment.

Previous research indicates that tobacco craving predicts relapse to smoking among adult smokers attempting to quit. We hypothesized a similar relationship between craving and lapse (any smoking following a period of abstinence) among adolescent smokers during the treatment phase of a clinical trial. A visit was considered a lapse visit if the participant reported smoking or had a carbon monoxide level of 7 ppm or greater subsequent to an abstinent visit. A total of 34 participants (mean age = 14.9 years [SD = 1.3]; mean cigarettes/day = 18.0 [SD = 7.6]; mean Fagerstr?m Test for Nicotine Dependence score = 6.8 [SD = 1.34]; 65% female), were included in the present analysis of 167 treatment visits. Logistic regression analyses showed a positive relationship between degree of craving, measured by the Questionnaire on Smoking Urges, and lapse during smoking cessation treatment (p = .013). Additionally, linear regression analyses demonstrated a strong positive association between cigarettes smoked per day and craving scores (p<.001). Taken together with other data, these findings suggest that degree of craving might influence tobacco abstinence for adolescent smokers. Thus monitoring and addressing craving appears useful to increase the success of adolescent smoking cessation.     

Efficacy of the nicotine inhaler in smoking reduction: A double-blind, randomized trial.

Many smokers are not ready to quit but are interested in changing their smoking behavior, particularly if such a change is associated with a reduction in health risk. The present study evaluated the efficacy of the nicotine inhaler in reducing smoking. Exploratory studies assessed whether reduction in smoking was associated with reduction in markers of disease risk. A total of 429 healthy smokers (smoking at least 20 cigarettes/day) were randomly assigned to either nicotine-containing or placebo inhalers, which subjects were allowed to use ad libitum for up to 1 year. The nicotine inhaler was significantly superior to placebo in achieving reduction in daily cigarette consumption by at least 50% after 4 months, compared with baseline (18% vs. 8%, p = .004). Active treatment promoted smoking cessation: 8% of subjects in the nicotine group and 1% in the placebo group were abstinent at month 15. Throughout the study, smoking reduction, per se, independent of treatment group, was associated with a statistically significant decrease in exhaled carbon monoxide and serum cotinine and thiocyanate. Smoking reduction also improved established risk markers for cardiovascular disease over 4 months. The incidence of adverse events did not differ significantly between the active and placebo groups. The most common treatment-related adverse events were throat irritation and cough. In conclusion, the nicotine inhaler can help smokers who are unable or unwilling to quit to reduce daily cigarette consumption, which may be a health benefit on its own and may further promote quitting.     

Over-the-counter availability of nicotine replacement therapy and smoking cessation.

In 1996, the FDA approved over-the-counter (OTC) availability of nicotine gum and two brands of nicotine skin patches. Little is known about how this reclassification has influenced the effectiveness and use of nicotine replacement therapy (NRT) and whether it has been a public health benefit. Data for the present study came from a prospective cohort study of 1,639 adult smokers surveyed by telephone in 1993, as part of the National Cancer Institute's Community Intervention Trial for Smoking Cessation (COMMIT), and resurveyed in 2001. NRT-assisted quit rates, NRT use rates, and the characteristics of NRT users were calculated before and after the 1996 OTC reclassification. Also calculated was the percentage of NRT users who quit by year. Results are presented for patch and gum separately and combined. OTC NRT use rates were lower for Hispanics and higher for those with no desire to quit at baseline. The quit rate decreased for patch-assisted quit attempts after OTC reclassification (22.5% to 18.5%, p = .05), but it did not change for gum-assisted quit attempts (11.9% to 10.5%, p = .54). NRT use rates increased for both patch and gum by about 60% following reclassification. A greater percentage of gum users had quit in the post-OTC period than in the pre-OTC period (9.7% vs. 14.6%, p = .05). Long-term quit rates in patch users were similar in both periods. Insurance coverage of NRT and concurrent attendance in a stop smoking clinic decreased for both patch- and gum-assisted attempts in the post-OTC period. The results suggest that OTC reclassification may have contributed to the increased use of NRT, compared with the pre-OTC period, whereas the efficacy for quitting decreased slightly for those using nicotine patch and remained about the same for those using the gum.     

Effects of low nicotine content cigarettes on smoke intake.

Cigarettes with selective reductions in nicotine delivery have been considered as potential tools to prevent or treat nicotine dependence or to reduce harm by virtue of reduced nicotine and nitrosamine delivery. An important question is whether individuals smoke these products more intensively, as has been shown to occur with ventilated-filter cigarettes. To investigate this issue, we compared conventional highly ventilated filter cigarettes, having very low tar and nicotine yields when smoked by Federal Trade Commission method (1 mg tar, 2 mg carbon monoxide [CO],.2 mg nicotine), with low nicotine content cigarettes, manufactured from a genetically modified strain of tobacco, which had higher tar but lower nicotine yield (14 mg tar, 13 mg CO,.02 mg nicotine). A total of 16 cigarette smokers participated in two 8-hr sessions (order counterbalanced) during which they smoked each type of cigarette ad libitum. Expired-air CO, plasma nicotine, and smoking topography measures were collected. Subjects showed significant increases in smoking when using the highly ventilated filter cigarettes, and puff volume was significantly greater than with the low nicotine content cigarettes. Subjects achieved an expired-air CO level 74% as high as with the low nicotine content cigarettes; the latter produced CO levels similar to those measured at baseline when subjects smoked their habitual brands of cigarettes. Plasma nicotine levels obtained when subjects smoked the highly ventilated filter cigarettes also were significantly higher than when they smoked the low nicotine content cigarettes. These results indicate that the delivery of substantial amounts of smoke, with selective reductions in nicotine yield, appears to prevent compensatory smoking behavior. Further studies should determine whether similar results are obtained in naturalistic environments.