Estimation of compliance with exclusive smoking of very low nicotine content cigarettes using plasma cotinine

The Impact of Reducing Nicotine Content on Adolescent Cigarette Smoking and Nicotine Exposure: Results From a Randomized Controlled Trial

INTRODUCTION

As the science base around the potential benefits of a reduced-nicotine standard for cigarettes grows, information on the potential effects on adolescent smokers is a high priority. The aim of this randomized trial was to test the influence of 3-week exposure to reduced nicotine cigarettes in a sample of adolescent daily smokers.

AIMS AND METHODS

In this double-blind, two-arm, randomized controlled trial (NCT0258731), following a 1-week baseline, adolescent daily smokers not currently intending to quit (ages 15-19 years, n = 66 randomized) were urn randomized to use either very low nicotine content (VLNC; 0.4 mg/g; n = 33) or normal nicotine content (NNC, 15.8 mg/g; n = 33) research cigarettes for 3 weeks. Participants attended five study sessions at our clinical laboratory. The primary outcome was average total cigarettes smoked per day (CPD; including both study and non-study cigarettes) at week 3.

RESULTS

Stepwise regression results demonstrated that compared with NNC cigarettes (n = 31), assignment to VLNC cigarettes (n = 29), was associated with 2.4 fewer CPD on average than NNC assignment (p < .05) week 3 when controlling for covariates (p < .01, Cohen's d = 0.52 n = 60 completed all procedures). VLNC cigarettes were also associated with lower levels of craving reduction than NNC cigarettes (Questionnaire on Smoking Urges Factor 2, p < .05). No group differences were found for secondary outcomes.

CONCLUSIONS

Adolescent participants assigned to VLNC use for 3 weeks smoked fewer total CPD relative to the NNC group. Overall, data suggest that a VLNC policy would reduce cigarette smoking in adolescents who smoke, but high rates of incomplete adherence suggest that youth may seek alternative sources of nicotine in this scenario.

IMPLICATIONS

The US Food and Drug Administration may enact a reduced-nicotine product standard that would affect all commercially available cigarettes. One important population affected by this policy would be adolescents who smoke. This study, the first clinical trial of VLNC cigarettes in adolescents, demonstrates that adolescents switched to VLNC cigarettes for 3 weeks reduced their CPD relative to the normal-nicotine cigarette control group, without leading to increased respiratory symptoms or increased withdrawal. Biomarkers indicated the use of other sources of nicotine, suggesting that such a policy will need to consider approaches to assist in transitioning away from smoking.

The effects of reduced nicotine content cigarettes on biomarkers of nicotine and toxicant exposure, smoking behavior and psychiatric symptoms in smokers with mood or anxiety disorders: A double-blind randomized trial

BACKGROUND

The U.S. Food and Drug Administration and the government of New Zealand have proposed a reduction of the nicotine content in cigarettes to very low levels. This study examined the potential effects of this regulation in smokers with affective disorders.

METHODS

In a randomized controlled parallel group trial conducted at two sites in the USA (Penn State University, Hershey, PA and Massachusetts General Hospital, Boston, MA) 188 adult smokers with a current (n = 118) or lifetime (n = 70) anxiety or unipolar mood disorder, not planning to quit in the next 6 months, were randomly assigned (1:1) to smoke either Usual Nicotine Content (UNC) (11.6 mg nicotine/cigarette) research cigarettes, or Reduced Nicotine Content (RNC) research cigarettes where the nicotine content per cigarette was progressively reduced to 0.2 mg in five steps over 18 weeks. Participants were then offered the choice to either receive assistance to quit smoking, receive free research cigarettes, or resume using their own cigarette brand during a 12-week follow-up period. Main outcomes were biomarkers of nicotine and toxicant exposure, smoking behavior and dependence and severity of psychiatric symptoms. The pre-registered primary outcome was plasma cotinine.

RESULTS

A total of 143 (76.1%) randomized participants completed the randomized phase of the trial, 69 (73.4%) in the RNC group and 74 (78.8%) in the UNC group. After switching to the lowest nicotine content cigarettes, compared to smokers in the UNC group, at the last randomized visit the RNC group had significantly lower plasma cotinine (metabolite of nicotine): difference between groups, -175.7, 95% CI [-218.3, -133.1] ng/ml. Urine NNAL (metabolite of NNK, a lung carcinogen), exhaled carbon-monoxide, cigarette consumption, and cigarette dependence were also significantly lower in the RNC group than the UNC group. No between-group differences were found on a range of other biomarkers (e.g. 8-isoprostanes) or health indicators (e.g. blood pressure), or on 5 different psychiatric questionnaires, including the Kessler K6 measure of psychological distress. At the end of the subsequent 12-week treatment choice phase, those randomized to the RNC group were more likely to have quit smoking, based on initial intent-to-treat sample, n = 188 (18.1% RNC v 4.3% UNC, p = 0.004).

CONCLUSION

Reducing nicotine content in cigarettes to very low levels reduces some toxicant exposures and cigarette addiction and increases smoking cessation in smokers with mood and/or anxiety disorders, without worsening mental health.

TRIAL REGISTRATION

TRN: NCT01928758, registered August 21, 2013.

Effect of menthol on nicotine reduction: Pooled results from two double-blind randomized controlled trials

BACKGROUND

Menthol upregulates nicotinic acetylcholine receptors and is associated with tobacco dependence. The effects of menthol when smoking cigarettes with varying low nicotine content up to 98 % (e.g., non-addicting) less than commercial cigarettes is not well understood. The U.S. Food and Drug Administration is considering two tobacco product standards in cigarettes including banning menthol and reducing nicotine content. These new standards have the potential to significantly reduce smoking initiation and maintenance by limiting the mechanistic effects of nicotine and menthol on the brain.

METHODS

We conducted two parallel randomized clinical trials of gradually reduced nicotine in cigarettes from 11.6 mg down to 0.2 mg nicotine/cigarette (very low nicotine content; VLNC) vs. usual nicotine content (11.6 mg; UNC) over an 18-week period in people who smoke cigarettes with low socioeconomic status (SES) and mental health conditions.

RESULTS

Compared to UNC, VLNC was associated with significant reductions in cotinine, cigarettes per day, expired carbon monoxide levels, nicotine dependence and symptomology. These associations did not differ between menthol and non-menthol cigarettes, except people who smoke menthol cigarettes had less of a cotinine reduction in the SES trial. The pooled odds ratio of being adherent with using only VLNC study cigarettes in the gradual nicotine reduction arm for people who smoke non-menthol vs. menthol cigarettes was 2.6 (95 % CI:1.0, 6.4; p-value: 0.04).

CONCLUSIONS

When nicotine is lowered to non-addicting levels, the results indicate an independent effect of menthol on the need to sustain nicotine intake in addicted people who smoke cigarettes.

Switching to Progressively Reduced Nicotine Content Cigarettes in Smokers With Low Socioeconomic Status: A Double-Blind Randomized Clinical Trial

INTRODUCTION

The Food and Drug Administration issued an advanced notice of proposed rulemaking for setting a product standard for nicotine levels in cigarettes, with an emphasis on minimally or non-addicting very low nicotine content (VLNC).

METHODS

A 33 week, two-arm, double-blind randomized trial conducted in Hershey, Pennsylvania, USA and Washington, DC, USA included adult daily cigarette smokers (≥5 cigarettes per day) with less than a college degree, and who had no plans to quit within the next six months. Participants were randomized to either reduced nicotine content (RNC) study cigarettes tapered every three weeks to a final VLNC (0.2 mg/cigarette) for six weeks or to usual nicotine content (UNC) study cigarettes (11.6 mg/cigarette). Outcomes included acceptability of study cigarettes measured by attrition (primary outcome), compliance, reduction in cigarette dependence and tobacco biomarkers, and post-intervention cessation.

RESULTS

The RNC (n = 122) versus UNC (n = 123) group had higher attrition (adjusted Hazard Ratio 3.4; 95% confidence interval [CI] 1.99 to 5.81). At the end of the intervention, cotinine levels were 50% lower in the RNC group (mean group difference -137 ng/mL; 95% CI -172, -102). The RNC group smoked fewer CPD (-4.1; 95% CI -6.44, -1.75) and had lower carbon monoxide levels (-4.0 ppm; 95% CI -7.7, -0.4). Forty seven percent (29/62) of the RNC group were biochemically-confirmed compliant with smoking VLNC cigarettes (mean cotinine = 8.9 ng/ml). At three month follow-up, only compliant VLNC smokers quit with an assisted quit attempt (N = 6/22, 27%).

CONCLUSIONS

This study supports a VLNC standard in cigarettes.

IMPLICATIONS

Differential dropout and noncompliance indicate some smokers had difficulty transitioning to cigarettes with reduced nicotine. These smokers will benefit from supplemental nicotine in medicinal or noncombustible tobacco products if a nicotine reduction standard is established. Other smokers successfully transitioned to very low nicotine content cigarettes exclusively and substantially reduced their exposure to nicotine.

Pharmacokinetic Profile of Spectrum Reduced Nicotine Cigarettes

INTRODUCTION

Spectrum research cigarettes have been developed with varying nicotine content for use in studies evaluating the effects of a regulatory policy reducing the permissible nicotine content in cigarettes. This study aimed to characterize the nicotine pharmacokinetic profile of Spectrum cigarettes.

METHODS

Twelve daily smokers attended four sessions and had blood nicotine, exhaled carbon monoxide, and subjective effects measured before and after smoking either a single cigarette of their preferred brand or high (10.9 mg/cigarette), medium (3.2 mg/cigarette), or low (0.2 mg/cigarette) nicotine content Spectrum research cigarettes, in a double-blind design with order counterbalanced.

RESULTS

The boost in blood nicotine concentration was dose-dependent, with a boost of 0.3, 3.9, and 17.3 ng/mL for low-, medium-, and high-nicotine content Spectrum cigarettes. The high dose Spectrum had a similar nicotine boost to the "preferred brand" cigarettes (19 ng/mL). Subjects took longer puffs on the low nicotine cigarettes, but smoked these cigarettes faster than other cigarette types. High nicotine Spectrum cigarettes reduced the urge to smoke more than other cigarette types.

CONCLUSIONS

This study shows that Spectrum research cigarettes produce blood nicotine absorption in a dose-dependent manner, and therefore, are appropriate for use in studies of nicotine reduction in cigarettes.

IMPLICATIONS

This is the first study to determine the pharmacokinetic profile of Spectrum reduced nicotine content research cigarettes following an overnight abstinence. These data could provide evidence to regulatory agencies about the effects of reduced nicotine cigarettes when considering regulations on tobacco reduction.

Nicotine Reduction in Cigarettes: Literature Review and Gap Analysis

BACKGROUND

The US Food and Drug Administration (FDA) is considering reducing nicotine levels in cigarettes to "minimally or non-addictive levels." However, important research gaps remain, and the FDA must determine when the available research is sufficient to support moving forward.

METHODS

The authors conducted a systematic review of research articles in PubMed relating to nicotine reduction. Building on a review of risk assessment best practices, the authors also developed a risk assessment framework for tobacco regulation and used it to guide a gap analysis of nicotine reduction research.

RESULTS

The final sample consisted of 78 articles. The majority examined either nicotine dependence on very low nicotine cigarettes (VLNCs) or markers of potential health effects of using VLNCs. One-third of the identified articles reported results from four large randomized controlled trials (RCTs). While these studies report promising results and suggest that a nicotine reduction rule would be a powerful tool to reduce cigarette smoking, our gap analysis suggests that there is a need for studies that better reflect the use and availability of a wide range of tobacco/nicotine products and the potential for dual- or multi-product use.

CONCLUSION

The current body of research on nicotine reduction is weighted towards RCTs, which is appropriate for a policy that has not yet been implemented anywhere in the world. The FDA must consider a wide range of factors that may impact a product standard's public health impact, including those difficult to assess in RCTs, such as a nicotine reduction rule's impact on smoking initiation and relapse.

IMPLICATIONS

This systematic review presents a gap analysis based on a risk assessment framework to help identify remaining research priorities to inform FDA's potential product standard to reduce nicotine levels in cigarettes. Quickly addressing those gaps would support the FDA's effort to develop a nicotine reduction product standard that will be effective and withstand legal challenges.

Do non-daily smokers compensate for reduced cigarette consumption when smoking very-low-nicotine-content cigarettes?

RATIONALE

The Food and Drug Administration is considering severely restricting the nicotine in cigarettes, to reduce smoking. A study showed that non-daily, intermittent smokers (ITS) randomized to very-low-nicotine-content cigarettes (VLNCCs) reduced their cigarette consumption.

OBJECTIVES

To assess whether increased smoking intensity of VLNCCs compensated for some of the reduced cigarette consumption.

METHODS

After a 2-week baseline smoking their own-brand cigarettes, 118 ITS were randomized to VLNCCs (~ 1 mg nicotine/g tobacco), and 120 to normal-nicotine-content cigarettes (NNCCs; ~ 16 mg/g) for 10 weeks. Laboratory measures of smoking intensity-total puff volume and carbon monoxide (CO) boost-assessed single cigarettes smoked in up to three laboratory topography sessions. Field measures assessed returned cigarette butts, averaged over up to five 2-week intervals: the mass of tobacco burned (computed from residual mass of butts) and the intensity of smoking (by scanning of returned filters). Analysis was by mixed model random effects models using baseline values as covariates.

RESULTS

ITS in the VLNCC group puffed less smoke in topography sessions (-38.50 mL [-75.21, -1.78]; p < 0.04), but showed no difference in CO boost. Participants in the VLNCC group burned 0.02 [0.04, 0.002] grams less tobacco per cigarette (p < 0.03). Analysis of filters showed their smoking intensity declined over time, compared to NNCC participants (p < 0.04). "Cheating" by smoking normal cigarettes did not moderate these effects.

CONCLUSIONS

ITS did not increase their smoking intensity when switched to VLNCCs; indeed, their smoking intensity decreased. Reductions in cigarette consumption seen when ITS are switched to VLNCCs were not compensated by increased smoking intensity.

Editorial: 5th Special Issue on behavior change, health, and health disparities

This Special Issue of Preventive Medicine (PM) is the 5th in a series on behavior change, health, and health disparities. Unhealthy behavior patterns (i.e., lifestyle choices) including cigarette smoking and other substance abuse, physical inactivity, unhealthy food choices, and non-adherence with recommended medical regimens, undermine U.S. population health by increasing risk for chronic disease and premature death. This Special Issue brings together scholarly contributions from the emerging area of tobacco regulatory science to examine current topics of critical importance to reducing the burden of cigarette smoking on U.S. population health. More specifically, three related topics are examined including (a) the potential for reducing smoking by adopting a national policy that would cap the nicotine content of cigarettes at minimally-addictive levels; (b) increasing scientific understanding of cigarette smoking and other tobacco use among populations that are especially vulnerable to initiating smoking, tobacco addiction, and its adverse health consequences; and (c) the potential of a harm-reduction strategy for reducing the burden of smoking by advocating that those who are unwilling or unable to quit nicotine use substitute electronic cigarettes or other non-combusted sources of nicotine for cigarettes in order to avoid exposure to the other toxins in tobacco smoke that are most responsible for smoking morbidity and mortality. While tremendous progress has been made in reducing overall U.S. smoking prevalence and its adverse health impacts, more needs to be done. This Special Issue offers some ideas that have the potential to make a substantive contribution towards that goal.