High-dose and low-dose varenicline for smoking cessation in adolescents: a randomised, placebo-controlled trial

The efficacy and acceptability of pharmacological monotherapies and e-cigarette on smoking cessation: a systemic review and network meta-analysis

Background and aims

Several pharmacological interventions, such as nicotine replacement therapy (NRT), varenicline, and bupropion, have been approved for clinical use of smoking cessation. E-cigarettes (EC) are increasingly explored by many RCTs for their potentiality in smoking cessation. In addition, some RCTs are attempting to explore new drugs for smoking cessation, such as cytisine. This network meta-analysis (NMA) aims to investigate how these drugs and e-cigarettes compare regarding their efficacy and acceptability.

Materials and methods

This systematic review and NMA searched all clinical studies on smoking cessation using pharmacological monotherapies or e-cigarettes published from January 2011 to May 2022 using MEDLINE, COCHRANE Library, and PsychINFO databases. NRTs were divided into transdermal (TDN) and oronasal nicotine (ONN) by administrative routes, thus 7 network nodes were set up for direct and indirect comparison. Two different indicators measured the efficacy: prevalent and continuous smoking abstinence. The drop-out rates measured the acceptability.

Results

The final 40 clinical studies included in this study comprised 77 study cohorts and 25,889 participants. Varenicline is more effective intervention to assist in smoking cessation during 16-32 weeks follow-up, and is very likely to prompt dropout. Cytisine shows more effectiveness in continuous smoking cessation but may also lead to dropout. E-cigarettes and oronasal nicotine are more effective than no treatment in encouraging prevalent abstinence, but least likely to prompt dropout. Finally, transdermal nicotine delivery is more effective than no treatment in continuous abstinence, with neither significant effect on prevalent abstinence nor dropout rate.

Conclusion

This review suggested and agreed that Varenicline, Cytisine and transdermal nicotine delivery, as smoking cessation intervention, have advantages and disadvantages. However, we had to have reservations about e-cigarettes as a way to quit smoking in adolescents.

Identifying determinants of varenicline adherence using the Theoretical Domains framework: a rapid review

BACKGROUND

Adhering to varenicline has been shown to significantly improve the chances of successfully quitting smoking, with studies indicating a twofold increase in 6-month quit rates. However, despite its potential benefits, many individuals struggle with maintaining good adherence to varenicline; thus there is a need to develop scalable strategies to help people adhere. As a first step to inform the development of an intervention to improve adherence to varenicline, we conducted a rapid literature review to identify: 1) modifiable barriers and facilitators to varenicline adherence, and 2) behaviour change techniques associated with increased adherence to varenicline.

METHODS

We searched MEDLINE, Embase, APA PsycINFO, CINAHL, and the Cochrane Central Register of Controlled Trials for relevant studies published between 2006 and 2022. Search terms included "varenicline," "smoking cessation," and "adherence," and their respective subject headings and synonyms. We screened and included studies reporting modifiable determinants of adherence to varenicline and then assessed quality, extracted modifiable determinants and mapped them to the Theoretical Domains Framework version 2 and the Behaviour Change Technique Taxonomy version 1.

RESULTS

A total of 1,221 titles were identified through the database searches; 61 met the eligibility criteria. Most of the studies were randomized controlled trials and predominantly focused on barriers to varenicline. Only nine studies explicitly mentioned behaviour change techniques used to help varenicline adherence. Eight domains were identified as barriers to varenicline adherence (behavioural regulation, memory, goals, intentions, beliefs about capabilities, beliefs about consequences, optimism/pessimism, and environmental context) and five as facilitators (knowledge, behavioural regulation, beliefs about capabilities, social influences, and environmental context).

CONCLUSIONS

This study identifies barriers and facilitators that should be addressed when developing a complex adherence intervention tailored to patients' needs based on modifiable determinants of medication adherence, some of which are under- used by existing adherence interventions. The findings from this review will inform the design of a theory-based healthbot planned to improve varenicline adherence in people undergoing smoking cessation treatment.

SYSTEMATIC REVIEW REGISTRATION

This study was registered with PROSPERO (# CRD42022321838).

Clinical Practice Guideline of Spanish Society of Pneumology and Thoracic Surgery (SEPAR) on Pharmacological Treatment of Tobacco Dependence 2023

INTRODUCTION

There are multiple systematic reviews and meta-analyses on the efficacy and safety of pharmacological treatments against nicotine dependence. However, there are few guidelines to answer frequent questions asked by a clinician treating a smoker. Therefore, the aim of this paper is to facilitate the treatment of tobacco addiction.

MATERIAL AND METHODS

12 PICO questions are formulated from a GLOBAL PICO question: "Efficacy and safety of pharmacological treatment of tobacco dependence". A systematic review was carried out to answer each of the questions and recommendations were made. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system was used to grade the certainty of the estimated effects and the strength of the recommendations.

RESULTS

Varenicline, nicotine replacement therapy (NRT), bupropion and cytisine are more effective than placebo. Varenicline and combined nicotine therapy are superior to the other therapies. In smokers with high dependence, a combination of drugs is recommended, being more effective those associations containing varenicline. Other optimization strategies with lower efficacy consist of increasing the doses, the duration, or retreat with varenicline. In specific populations varenicline or NRT is recommended. In hospitalized, the treatment of choice is NRT. In pregnancy it is indicated to prioritize behavioral treatment. The financing of smoking cessation treatments increases the number of smokers who quit smoking. There is no scientific evidence of the efficacy of pharmacological treatment of smoking cessation in adolescents.

CONCLUSIONS

The answers to the 12 questions allow us to extract recommendations and algorithms for the pharmacological treatment of tobacco dependence.

Mobile Phone-Based Interventions for Smoking Cessation Among Young People: Systematic Review and Meta-Analysis

Background

Mobile phone-based cessation interventions have emerged as a promising alternative for smoking cessation, while evidence of the efficacy of mobile phone-based smoking cessation programs among young people is mixed.

Objective

This study aimed to determine the efficacy of mobile phone-based interventions compared to usual practice or assessment-only controls on smoking cessation in young people.

Methods

In this systematic review and meta-analysis, we searched Cochrane Library, Embase, PubMed, and Web of Science on March 8, 2023. We included randomized controlled trials that examined the efficacy of mobile phone-based interventions on smoking cessation in young people (age ≤30 years). The risk of bias was assessed with Cochrane Risk of Bias 2.

Results

A total of 13 eligible studies, comprising 27,240 participants, were included in this analysis. The age range of the participants was between 16 and 30 years. Nine studies were SMS text messaging interventions, and 4 studies were app-based interventions. The duration of the smoking cessation intervention varied from 5 days to 6 months. The included studies were conducted in the following countries: the United States, China, Sweden, Canada, Switzerland, and Thailand. The meta-analysis revealed that SMS text messaging interventions significantly improved continuous abstinence rates compared to inactive control conditions (risk ratio [RR] 1.51, 95% CI 1.24-1.84). The subgroup analysis showed pooled RRs of 1.90 (95% CI 1.29-2.81), 1.64 (95% CI 1.23-2.18), and 1.35 (95% CI 1.04-1.76) for continuous abstinence at the 1-, 3-, and 6- month follow-up, respectively. Pooling across 7 studies, SMS text messaging interventions showed efficacy in promoting 7-day point prevalence abstinence (PPA), with an RR of 1.83 (95% CI 1.34-2.48). The subgroup analysis demonstrated a significant impact at the 1- and 3-month follow-ups, with pooled RRs of 1.72 (95% CI 1.13-2.63) and 2.54 (95% CI 2.05-3.14), respectively, compared to inactive control conditions. However, at the 6-month follow-up, the efficacy of SMS text messaging interventions in promoting 7-day PPA was not statistically significant (RR 1.45, 95% CI 0.92-2.28). In contrast, app-based interventions did not show significant efficacy in promoting continuous abstinence or 7-day PPA. However, it is important to note that the evidence for app-based interventions was limited.

Conclusions

SMS text messaging-based smoking cessation interventions compared to inactive controls were associated with abstinence among young people and could be considered a viable option for smoking cessation in this population. More research is needed on smoking cessation apps, especially apps that target young people. Future research should focus on identifying the most effective mobile phone-based cessation approaches and on developing strategies to increase their uptake and intention.

Nationwide experiences with youth-targeted smoking and nicotine product cessation

INTRODUCTION

Most adolescent and young adult (youth) smokers and users of novel nicotine products wish to quit. Little is known, at a population level, about youth cessation activities, and the counselor's experiences in working with youth smoking and nicotine product cessation.

METHODS

A questionnaire was mailed to all 98 municipalities in Denmark on 31 October 2022. Youths were defined as those aged 16-25 years. The participation rate was 96% (n=94). Simple descriptive statistics were performed.

RESULTS

This survey explored youth-targeted smoking and nicotine product cessation activities and ex-periences from municipality counselors across the whole nation. Overall, 60% of the Danish municipal counselors had low/very low/no personal experience with youth cessation interventions, 89% found it dif-ficult to work with youth counseling, 90% found it difficult to recruit youth to nicotine cessation services, and only 25% of the active municipalities were described as highly experienced. A higher percentage of the highly experienced municipalities reported that they share the responsibility of recruitment to cessation services with schools, counsel youths in separate groups from adults, and have good experiences with online counseling.

CONCLUSIONS

This Danish nationwide survey showed that even in a country with very well-organized and free-of-charge cessation counseling programs, very few municipalities give assistance to youth, and most find it difficult to work with youth. Cessation services have been designed for adult smokers and seem to have failed to meet the needs of young smokers and users of novel nicotine products, at least in Denmark. There is an urgent need for research on how to effectively recruit youth to cessation services, and what works to help youth quit.

Medication Adherence in Tobacco Cessation Clinical Trials

Adherence is a critical mediator of treatment outcome across health conditions and low rates of adherence undermine success in smoking cessation treatment. This narrative review provides an overview of different techniques that can be used to measure adherence to smoking cessation treatments and outlines strategies to address treatment adherence. Techniques to measure adherence include conducting pill counts, collecting self-reports of adherence, directly observed therapy, biochemical verification methods, and electronic data collection via medication events monitoring systems. Techniques examined for increasing tobacco cessation treatment adherence include counseling, automated adherence calls, feedback from electronic monitors, contingency management and directly observed therapy. Adherence monitoring and optimization should be a standard component of smoking cessation treatment research.

A randomized controlled trial of varenicline and brief behavioral counseling delivered by lay counselors for adolescent vaping cessation: Study protocol

Background

Approximately one-fifth of high-school seniors and college students currently vape nicotine. Adolescents express a desire to quit vaping, and case reports have shown promise for e-cigarette tapering with dual behavioral and pharmacologic therapies. However, there are no published clinical trials to date that test these intervention approaches for adolescent nicotine vaping cessation. In this three-arm randomized, placebo-controlled, parallel-group study, we aim to assess the efficacy of varenicline in combination with brief behavioral counseling and texting support on vaping cessation in adolescents dependent on vaped nicotine.

Methods

The study will enroll 300 individuals between the ages of 16–25 with daily or near-daily nicotine vaping who reside in the Greater Boston area. Participants will be randomly assigned in a 1:1:1 ratio in blocks of six to one of the three arms: (1) a 12-week course of varenicline titrated to 1 mg bid, brief behavioral counseling delivered by a lay counselor, and an introduction to This is Quitting (TIQ) texting support created by the Truth Initiative; (2) a 12-week course of placebo, brief behavioral counseling, and TIQ; and (3) 12 weeks of enhanced usual care, consisting of advice to quit and an introduction to TIQ. The primary outcome will be biochemically verified continuous vaping abstinence at the end of the treatment (week 12). Secondary outcomes include continuous abstinence at follow-up (week 24), 7-day point prevalence abstinence at weeks 12 and 24, safety and tolerability of varenicline in an adolescent vaping population, as well as change in mood and nicotine withdrawal symptoms across the intervention period. Exploratory outcomes include change in comorbid substance use behaviors and nicotine dependence. Analysis will be intent-to-treat, with multiple imputation sensitivity analyses for participants with missing or incomplete outcome data.

Discussion

This is the first study to evaluate varenicline in combination with a novel, brief, lay counselor delivered vaping cessation program for adolescents who vape nicotine. Results will inform clinicians on the effectiveness and acceptability of this promising, but not yet tested intervention.

Clinical trial registration: ClinicalTrials.gov, identifier NCT05367492.

ADHD symptoms and smoking outcomes in a randomized controlled trial of varenicline for adolescent and young adult tobacco cessation

BACKGROUND

Most adult daily smokers try their first cigarette during adolescence. Attention-Deficit Hyperactivity Disorder (ADHD) in adolescents is associated with increased risk for cigarette smoking. The impact of ADHD symptoms on smoking cessation among adolescents has been less well-studied. The present secondary data analysis from a clinical trial of varenicline examined ADHD symptoms as a moderator of smoking cessation in adolescents and young adults.

METHODS

The double-blind, placebo-controlled trial included treatment-seeking daily cigarette smokers ages 14 - 21 (N = 157) randomized to receive a 12-week course of varenicline or placebo, added to weekly smoking cessation counseling. At pre-treatment assessment, participants were administered a self-report measure of ADHD symptoms, the ADHD - Rating Scale (ADHD-RS). High (≥5) versus low (<5) and continuous ADHD-RS symptom counts in both hyperactive/impulsive (HI) and inattention (IA) domains were examined as predictors of smoking outcomes.

RESULTS

Participants with high IA symptoms at baseline were less likely to achieve 7-day point prevalence abstinence (PPA) at weekly visits (p = .001) during active treatment and end-of-treatment (p = .002) compared to those with low IA symptoms. In contrast, high HI symptoms did not predict differences in 7-day PPA or end-of-treatment abstinence versus low symptoms (p's ≥ .07). These findings were not modified by varenicline versus placebo treatment assignment.

CONCLUSIONS

ADHD IA symptoms were associated with poorer cessation outcomes among adolescent smokers. These findings warrant additional investigation into how ADHD symptoms may be accounted for in smoking cessation interventions for adolescents and young adults.

Clinical approach to the treatment of e-cigarette use among adolescents

E-cigarette use remains a serious public health threat for adolescents in the United States. Pediatric providers can intervene early to prevent the adverse, and sometimes life-long, health consequences of e-cigarette use. This article reviews the clinical management of e-cigarette use among adolescents using the "Ask-Counsel-Treat" model. This model was recently introduced by the American Academy of Pediatrics to help pediatric healthcare providers manage e-cigarette screening, counseling, and treatment. Behavioral treatments for e-cigarette cessation can be delivered via multiple formats, including via text, in-person, or online. Additionally, pediatric healthcare providers may consider the off-label use of nicotine replacement therapy in individuals less than 18 years of age to alleviate some of the symptoms of nicotine withdrawal. Further research is needed to inform the design and implementation of effective e-cigarette cessation strategies for adolescents.

A pilot feasibility study of a behavioral intervention for nicotine vaping cessation among young adults delivered via telehealth

BACKGROUND

Nicotine vaping among youth has increased, warranting concern from tobacco control proponents. Many youth who vape indicate interest in quitting; however, few empirically supported vaping cessation interventions exist. This pilot feasibility study adapted an established behavioral intervention, contingency management (CM), delivered via telehealth to promote vaping cessation among young adults.

METHODS

Participants (N = 27; ages 17-21) vaping nicotine regularly were recruited via social media and digital advertisements from across the US (June 2020-January 2021). Participants were randomized at approximately 4:1 to CM or Monitoring control (22:5). CM was delivered through DynamiCare Health's smartphone app for 4 weeks, in which financial incentives were delivered contingent on abstinent cotinine samples after the quit day until the end of treatment (EOT; Days 7-28; 10 expected submissions). Control participants earned incentives for submitting cotinine, regardless of abstinence. Feasibility, acceptability, and abstinence was collected throughout treatment, at EOT, and at 1-month follow-up.

RESULTS

The majority of enrolled participants completed treatment (Monitoring: 5/5; CM: 20/22), and intervention components were rated favorably overall (> 80%). CM participants submitted 112/220 (55%) abstinent cotinine samples throughout the quit attempt, while the Monitoring group submitted 4/50 (8%) negative samples. There were no differences in abstinence between groups at EOT or follow-up.

CONCLUSION

This pilot study of a telehealth-based youth vaping cessation intervention demonstrated preliminary feasibility and acceptability. These results suggest that CM for young adult vaping cessation, delivered remotely, is a promising direction for future work and fully powered trials are warranted to assess intervention efficacy.

Tobacco Smoking and Liver Cancer Risk: Potential Avenues for Carcinogenesis

Smoking a cigarette generates over 4000 chemicals that have a deleterious impact on each part of the human body. It produces three main severe effects on the liver organ: oncogenic, immunological, and indirect or direct toxic effects. It results in the production of cytotoxic substances, which raises fibrosis and necro-inflammation. Additionally, it also directs the production of pro-inflammatory cytokines tumour necrosis factor alfa (TNF-α) and interleukins (IL-1β, IL-6) that will be responsible for the chronic liver injury. Furthermore, it gives rise to secondary polycythemia and successively raises the turnover and mass of red cells, which might be a common factor responsible for the development of oxidative stress in the liver due to iron overload. It also produces chemicals that are having oncogenic properties and raises the risk of liver cancer especially in sufferers of chronic hepatitis C. Smoking modulates both humoral and cell-mediated responses by restricting the proliferation of lymphocytes and inducing their apoptosis and ultimately decreasing the surveillance of cancer cells. Moreover, it has been determined that heavy smoking impacts the response of hepatitis C patients to interferon (IFN) therapy through different mechanisms, which can be improved by phlebotomy. Efforts are being made in different nations in decreasing the prevalence of smoking to improve premature death and ill effects of their nation's individuals.

Population pharmacokinetics and exposure-response analyses of varenicline in adolescent smokers

Varenicline is an approved smoking cessation aid in adults. Population pharmacokinetics (popPK) and exposure–response (ER) (continuous abstinence rates [CAR] weeks 9‒12 and nausea/vomiting incidence) for varenicline in adolescent smokers were characterized using data from two phase 1 and one phase 4 studies. A one‐compartment popPK model with first‐order absorption and elimination adequately fitted the observed data. The effect of female sex on apparent clearance was significant. Apparent volume of distribution increased with body weight and decreased by 24%, 15%, and 14% for black race, “other” race, and female sex, respectively. The observed range of exposure in the phase 4 study was consistent with that expected for each dose and body‐weight group from the results obtained in adolescent PK studies, supporting that varenicline dose and administration were appropriate in the study. The relationship between CAR9‒12 and varenicline area under the concentration–time curve (AUC) from 0 to 24 hours (AUC₂₄) was nonsignificant (p = 0.303). Nausea/vomiting incidence increased with AUC₂₄ (p < 0.001) and was higher in females. Varenicline PK and ER for tolerability in adolescent smokers were comparable with adults, while ER for efficacy confirmed the negative results reported in the phase 4 study.