Increasing Quit Attempts by Transitioning to Very Low Nicotine Content Cigarettes Versus Reducing Number of Cigarettes Per Day: A Secondary Analysis of an Exploratory Randomized Trial

Associations between compliance with very low nicotine content (VLNC) cigarettes, abstinence self-efficacy, and quit outcomes in a pilot smoking cessation trial

BACKGROUND

Switching to Very Low Nicotine Content (VLNC) cigarettes reduces toxicant exposure and nicotine dependence, and may improve smoking cessation. However, non-compliance with VLNCs is often high, which may reduce their effectiveness. Here, we conducted secondary analyses of a pilot smoking cessation trial utilizing VLNCs to examine associations between pre-cessation VLNC compliance and changes in smoking rate, dependence, and abstinence self-efficacy, as well as quit outcomes.

METHODS

People who smoke daily (n=35) engaged in a 4-week pre-cessation intervention including VLNCs, transdermal nicotine patch, and behavioral counseling. After quit date, participants received 8 weeks of nicotine replacement therapy and 4 additional behavioral sessions, and were followed for 10 weeks to assess abstinence. Compliance with VLNCs was assessed biweekly during pre-cessation using timeline follow-back. Statistical analyses examined associations between VLNC compliance and a) changes in smoking rate, dependence and abstinence self-efficacy over the course of study cigarette use; and b) time to relapse, controlling for other smoking variables.

RESULTS

Greater compliance during the second half of study cigarette use was associated with subsequent improvement in self-efficacy (p<.05). Increased self-efficacy and VLNC compliance both predicted lower likelihood of relapse. Nicotine dependence and cigarettes per day both decreased following study cigarette use, but were unrelated to compliance or relapse.

CONCLUSIONS

Compliance with VLNCs prior to quitting increased abstinence self-efficacy and predicted better quit outcomes above and beyond baseline smoking characteristics. Although preliminary, these findings suggest that identifying strategies to promote exclusive use of VLNCs during a brief pre-cessation window may be beneficial.

A systematic review and meta-analysis of interventions to induce attempts to quit tobacco among adults not ready to quit

The prevalence of past-year smoking cessation remains below 10% in the U.S. Most who smoke are not ready to quit in the near future. Cessation requires both (a) initiating a quit attempt (QA) and (b) maintaining abstinence. Most research has focused on abstinence among people already motivated to quit. We systematically reviewed interventions to promote QAs among people not motivated to quit tobacco. We searched PubMed, CENTRAL, PsycINFO, Embase, and our personal libraries for randomized trials of tobacco interventions that reported QAs as an outcome among adults not ready to quit. We screened studies and extracted data in duplicate. We pooled findings of the 25 included studies using Mantel-Haenszel random effects meta-analyses when ≥ 2 studies tested the same intervention. Most (24) trials addressed cigarettes and one addressed smokeless tobacco. Substantial heterogeneity among trials resulted in a series of small meta-analyses. Findings indicate varenicline may increase QAs more than no varenicline, n = 320; RR = 1.4, 95% CI [1.1, 1.7]; I² = 0%, and nicotine replacement therapy (NRT) may increase QAs more than no NRT, n = 2,568; RR = 1.1, 95% CI [1.02, 1.3]; I² = 0%. Pooled effects for motivational counseling, reduction counseling, and very low nicotine content cigarettes showed no clear evidence of benefit or harm. The evidence was judged to be of medium to very low certainty due to imprecision, inconsistency, and risk of bias, suggesting that further research is likely to change interpretation of our results. Findings demonstrate the need for more high-quality research on interventions to induce QAs among adults not ready to quit tobacco. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Non-nicotine constituents in cigarette smoke extract enhance nicotine addiction through monoamine oxidase A inhibition

Tobacco addiction has been largely attributed to nicotine, a component in tobacco leaves and smoke. However, extensive evidence suggests that some non-nicotine components of smoke should not be overlooked when considering tobacco dependence. Yet, their individual effect and synergistic effect on nicotine reinforcement remain poorly understood. The study herein focused on the role of non-nicotine constituents in promoting the effects of nicotine and their independent reinforcing effects. Denicotinized cigarettes were prepared by chemical extracting of cut tobacco, and the cigarette smoke extracts (CSE, used as a proxy for non-nicotine ingredients) were obtained by machine-smoking the cigarettes and DMSO extraction. The compositions of harmful components, nicotine, and other minor alkaloids in both cut tobacco and the CSE of experimental denicotinized cigarettes were examined by GC-MS, and compared with 3R4F reference cigarettes. individually and in synergy with nicotine were determined by conditioned place preference (CPP), dopamine (DA) level detection, the open field test (OFT), and the elevated plus maze (EPM). Finally, the potential enhancement mechanism of non-nicotinic constituents was investigated by nicotine metabolism and monoamine oxidase A (MAOA) activity inhibition in the striatum of mice and human recombinant MAOA. Thenicotine content in smoke from the experimental denicotinized cigarettes (under ISO machine-smoking conditions) was reduced by 95.1% and retained most minor alkaloids, relative to the 3R4F reference cigarettes. It was found that non-nicotine constituents increased acute locomotor activities. This was especially pronounced for DA levels in NAc and CPP scores, decreased the time in center zone. There were no differences in these metrics with DNC group when compared to the NS group. Non-nicotine constituents alone did not show reinforcing effects in CPP or striatum DA levels in mice. However, in the presence of nicotine, non-nicotine constituents further increased the reinforcing effects. Furthermore, non-nicotine constituents may enhance nicotine's reinforcing effects by inhibiting striatum MAOA activity rather than affecting nicotine metabolism or total striatum DA content in mice. These findings expand our knowledge of the effect on smoking reinforcement of non-nicotine constituents found in tobacco products.

Nicotine Standards in the United States

This Special Issue on nicotine standards in the United States will address many of the questions raised in the Advance Notice of Proposed Rulemaking (ANPRM) through a series of policy commentaries and timely empirical studies across a variety of topic areas within the proposed comprehensive nicotine standards plan. The questions addressed in this issue include: (1) the threshold dose of nicotine (and other constituents) that would lead to minimally addictive cigarettes; (2) the effects of a nicotine product standard in smokers with co-morbidity, youth and young adult smokers, and menthol smokers; (3) a step-down or targeted data approach to reducing nicotine in cigarettes; (4) perceptions and communications about product standards; and (5) requirements associated with the implementation of a nicotine product standard.