Nicotine patch preloading for smoking cessation (the preloading trial): study protocol for a randomized controlled trial

[Perioperative smoking cessation (conventional smoking and e-cigarettes) in 2023. A narrative review of the literature]

INTRODUCTION

Tobacco addiction is the leading cause of preventable death. During the perioperative period, patients who smoke are at increased risk of systemic as well as surgical site complications.

STATE OF THE ART

Surgery is an ideal time for change of lifestyle habits. It is vital to seize this opportunity to improve the patient's health in the long- as well as the short-term. Smoking cessation should be encouraged in all surgical patients. Initiating smoking cessation combines pharmacological treatment and a behavioral approach. In this field, significant advances have been recorded over the last decade. This review proposes a practical approach that every practitioner will be able to apply.

PERSPECTIVES

In this review, we will also examine ongoing research, particularly as regards vaccination and the place of biomarkers.

CONCLUSIONS

Smoking represents a major source of health-related complications. Smoking cessation must therefore remain a priority in the management of medical and surgical patients.

Preloaded combination nicotine replacement therapy for smoking cessation in Kazakhstan: A randomized controlled trial study protocol

BACKGROUND

Tobacco use is a major cause of premature death and disease in Kazakhstan, with over 22,500 deaths per year. Although efforts have been made to control tobacco use, smoking-related deaths have continued to increase. One strategy to help smokers quit is to use nicotine replacement therapy (NRT), with combination NRT resulting in higher long-term quit rates than a single form of NRT. A study aims to determine the effectiveness of preloaded combination NRT on smoking cessation, the change in health-related quality of life due to smoking cessation, and explore treatment adherence perceptions.

METHODS AND ANALYSIS

The study will be conducted as a randomized, single-blind superiority trial, with 100 participants in each arm. The trial will be carried out at the National Research Cardiac Surgery Center, Astana, Kazakhstan, and will recruit current smokers aged 18 years and above with a motivation to quit. Participants will be randomly allocated to either the intervention group or the control group. The former will receive preloaded combination NRT, while the latter will receive fast-acting NRT alone. The primary outcome measure will be sustained abstinence from smoking after six months. Secondary outcome measures will include health-related quality of life and adherence to the treatment.

DISCUSSION

The study may gather further evidence that a combination NRT is more efficient than a fast-acting NRT alone. The findings of this study may help to improve tobacco cessation strategies in Kazakhstan and other countries with high smoking prevalence rates.

TRIAL REGISTRATION NUMBER

NCT05484505.

Different doses, durations and modes of delivery of nicotine replacement therapy for smoking cessation

BACKGROUND

Nicotine replacement therapy (NRT) aims to replace nicotine from cigarettes. This helps to reduce cravings and withdrawal symptoms, and ease the transition from cigarette smoking to complete abstinence. Although there is high-certainty evidence that NRT is effective for achieving long-term smoking abstinence, it is unclear whether different forms, doses, durations of treatment or timing of use impacts its effects.

OBJECTIVES

To determine the effectiveness and safety of different forms, deliveries, doses, durations and schedules of NRT, for achieving long-term smoking cessation.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register for papers mentioning NRT in the title, abstract or keywords, most recently in April 2022.

SELECTION CRITERIA

We included randomised trials in people motivated to quit, comparing one type of NRT use with another. We excluded studies that did not assess cessation as an outcome, with follow-up of fewer than six months, and with additional intervention components not matched between arms. Separate reviews cover studies comparing NRT to control, or to other pharmacotherapies.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods. We measured smoking abstinence after at least six months, using the most rigorous definition available. We extracted data on cardiac adverse events (AEs), serious adverse events (SAEs) and study withdrawals due to treatment.  MAIN RESULTS: We identified 68 completed studies with 43,327 participants, five of which are new to this update. Most completed studies recruited adults either from the community or from healthcare clinics. We judged 28 of the 68 studies to be at high risk of bias. Restricting the analysis only to those studies at low or unclear risk of bias did not significantly alter results for any comparisons apart from the preloading comparison, which tested the effect of using NRT prior to quit day whilst still smoking.  There is high-certainty evidence that combination NRT (fast-acting form plus patch) results in higher long-term quit rates than single form (risk ratio (RR) 1.27, 95% confidence interval (CI) 1.17 to 1.37; I2 = 12%; 16 studies, 12,169 participants). Moderate-certainty evidence, limited by imprecision, indicates that 42/44 mg patches are as effective as 21/22 mg (24-hour) patches (RR 1.09, 95% CI 0.93 to 1.29; I2 = 38%; 5 studies, 1655 participants), and that 21 mg patches are more effective than 14 mg (24-hour) patches (RR 1.48, 95% CI 1.06 to 2.08; 1 study, 537 participants). Moderate-certainty evidence, again limited by imprecision, also suggests a benefit of 25 mg over 15 mg (16-hour) patches, but the lower limit of the CI encompassed no difference (RR 1.19, 95% CI 1.00 to 1.41; I2 = 0%; 3 studies, 3446 participants). Nine studies tested the effect of using NRT prior to quit day (preloading) in comparison to using it from quit day onward. There was moderate-certainty evidence, limited by risk of bias, of a favourable effect of preloading on abstinence (RR 1.25, 95% CI 1.08 to 1.44; I2 = 0%; 9 studies, 4395 participants). High-certainty evidence from eight studies suggests that using either a form of fast-acting NRT or a nicotine patch results in similar long-term quit rates (RR 0.90, 95% CI 0.77 to 1.05; I2 = 0%; 8 studies, 3319 participants). We found no clear evidence of an effect of duration of nicotine patch use (low-certainty evidence); duration of combination NRT use (low- and very low-certainty evidence); or fast-acting NRT type (very low-certainty evidence). Cardiac AEs, SAEs and withdrawals due to treatment were all measured variably and infrequently across studies, resulting in low- or very low-certainty evidence for all comparisons. Most comparisons found no clear evidence of an effect on these outcomes, and rates were low overall. More withdrawals due to treatment were reported in people using nasal spray compared to patches in one study (RR 3.47, 95% CI 1.15 to 10.46; 1 study, 922 participants; very low-certainty evidence) and in people using 42/44 mg patches in comparison to 21/22 mg patches across two studies (RR 4.99, 95% CI 1.60 to 15.50; I2 = 0%; 2 studies, 544 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

There is high-certainty evidence that using combination NRT versus single-form NRT and 4 mg versus 2 mg nicotine gum can result in an increase in the chances of successfully stopping smoking. Due to imprecision, evidence was of moderate certainty for patch dose comparisons. There is some indication that the lower-dose nicotine patches and gum may be less effective than higher-dose products. Using a fast-acting form of NRT, such as gum or lozenge, resulted in similar quit rates to nicotine patches. There is moderate-certainty evidence that using NRT before quitting may improve quit rates versus using it from quit date only; however, further research is needed to ensure the robustness of this finding. Evidence for the comparative safety and tolerability of different types of NRT use is limited. New studies should ensure that AEs, SAEs and withdrawals due to treatment are reported.

Behavioural support and nicotine replacement therapy for smokeless tobacco cessation: protocol for a pilot randomised-controlled multi-country trial

BACKGROUND

Smokeless tobacco (ST) is consumed globally by more than 350 million people, with approximately 85% of all users based in South and Southeast Asia. In this region, ST products are cheap and easily accessible. Evidence-based interventions to people quit ST use are lacking. This study aims to test the feasibility of conducting a future definitive trial of ST cessation, using a culturally adapted behavioural intervention, and/or nicotine replacement therapy (NRT) in three South Asian countries.

METHODS

We will conduct a factorial design, randomised-controlled pilot trial in Bangladesh, India and Pakistan. Daily ST users will be recruited from primary health care settings in Dhaka, Noida and Karachi. Participants will be individually randomised to receive intervention A (4 or 6 mg NRT chewing gum for 8-weeks), intervention B (BISCA: face-to-face behavioural support for ST cessation), a combination of interventions A and B or usual care (Very Brief Advice - VBA). The participants will provide demographic and ST use related data at baseline, and at 6, 12 and 26 weeks of follow-up. Salivary cotinine samples will be collected at baseline and 26 weeks. The analyses will undertake an assessment of the feasibility of recruitment, randomisation, data collection and participant retention, as well as the feasibility of intervention delivery. We will also identify potential cessation outcomes to inform the main trial, understand the implementation, context and mechanisms of impact through a process evaluation and, thirdly, establish health resource use and impact on the quality of life through health economic data.

DISCUSSION

The widespread and continued use of ST products in South Asia is consistent with a high rate of associated diseases and negative impact on the quality of life. The identification of feasible, effective and cost-effective interventions for ST is necessary to inform national and regional efforts to reduce ST use at the population level. The findings of this pilot trial will inform the development of larger trials for ST cessation among South Asian users, with relevance to wider regions and populations having high rates of ST use.

TRIAL REGISTRATION

ISRCTN identifier 65109397.

Smoking cessation medicines and e-cigarettes: a systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

Cigarette smoking is one of the leading causes of early death. Varenicline [Champix (UK), Pfizer Europe MA EEIG, Brussels, Belgium; or Chantix (USA), Pfizer Inc., Mission, KS, USA], bupropion (Zyban; GlaxoSmithKline, Brentford, UK) and nicotine replacement therapy are licensed aids for quitting smoking in the UK. Although not licensed, e-cigarettes may also be used in English smoking cessation services. Concerns have been raised about the safety of these medicines and e-cigarettes.

OBJECTIVES

To determine the clinical effectiveness, safety and cost-effectiveness of smoking cessation medicines and e-cigarettes.

DESIGN

Systematic reviews, network meta-analyses and cost-effectiveness analysis informed by the network meta-analysis results.

SETTING

Primary care practices, hospitals, clinics, universities, workplaces, nursing or residential homes.

PARTICIPANTS

Smokers aged ≥ 18 years of all ethnicities using UK-licensed smoking cessation therapies and/or e-cigarettes.

INTERVENTIONS

Varenicline, bupropion and nicotine replacement therapy as monotherapies and in combination treatments at standard, low or high dose, combination nicotine replacement therapy and e-cigarette monotherapies.

MAIN OUTCOME MEASURES

Effectiveness - continuous or sustained abstinence. Safety - serious adverse events, major adverse cardiovascular events and major adverse neuropsychiatric events.

DATA SOURCES

Ten databases, reference lists of relevant research articles and previous reviews. Searches were performed from inception until 16 March 2017 and updated on 19 February 2019.

REVIEW METHODS

Three reviewers screened the search results. Data were extracted and risk of bias was assessed by one reviewer and checked by the other reviewers. Network meta-analyses were conducted for effectiveness and safety outcomes. Cost-effectiveness was evaluated using an amended version of the Benefits of Smoking Cessation on Outcomes model.

RESULTS

Most monotherapies and combination treatments were more effective than placebo at achieving sustained abstinence. Varenicline standard plus nicotine replacement therapy standard (odds ratio 5.75, 95% credible interval 2.27 to 14.90) was ranked first for sustained abstinence, followed by e-cigarette low (odds ratio 3.22, 95% credible interval 0.97 to 12.60), although these estimates have high uncertainty. We found effect modification for counselling and dependence, with a higher proportion of smokers who received counselling achieving sustained abstinence than those who did not receive counselling, and higher odds of sustained abstinence among participants with higher average dependence scores. We found that bupropion standard increased odds of serious adverse events compared with placebo (odds ratio 1.27, 95% credible interval 1.04 to 1.58). There were no differences between interventions in terms of major adverse cardiovascular events. There was evidence of increased odds of major adverse neuropsychiatric events for smokers randomised to varenicline standard compared with those randomised to bupropion standard (odds ratio 1.43, 95% credible interval 1.02 to 2.09). There was a high level of uncertainty about the most cost-effective intervention, although all were cost-effective compared with nicotine replacement therapy low at the £20,000 per quality-adjusted life-year threshold. E-cigarette low appeared to be most cost-effective in the base case, followed by varenicline standard plus nicotine replacement therapy standard. When the impact of major adverse neuropsychiatric events was excluded, varenicline standard plus nicotine replacement therapy standard was most cost-effective, followed by varenicline low plus nicotine replacement therapy standard. When limited to licensed interventions in the UK, nicotine replacement therapy standard was most cost-effective, followed by varenicline standard.

LIMITATIONS

Comparisons between active interventions were informed almost exclusively by indirect evidence. Findings were imprecise because of the small numbers of adverse events identified.

CONCLUSIONS

Combined therapies of medicines are among the most clinically effective, safe and cost-effective treatment options for smokers. Although the combined therapy of nicotine replacement therapy and varenicline at standard doses was the most effective treatment, this is currently unlicensed for use in the UK.

FUTURE WORK

Researchers should examine the use of these treatments alongside counselling and continue investigating the long-term effectiveness and safety of e-cigarettes for smoking cessation compared with active interventions such as nicotine replacement therapy.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016041302.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 59. See the NIHR Journals Library website for further project information.

Pharmacological strategies for smoking cessation in patients with chronic obstructive pulmonary disease: a pragmatic review

Introduction: Chronic obstructive pulmonary disease (COPD) is progressive inflammatory disease of the lungs in which smoking plays a significant pathogenic role. Smoking cessation is the only therapeutic intervention which was demonstrated to interfere with disease progression. Smoking cessation intervention can benefit from pharmacological therapies such as nicotine replacement therapies, bupropion, or varenicline which can be given individually or in combination, their effectiveness being demonstrated in various clinical trials enrolling COPD patients.Areas covered: The authors provide a pragmatic discussion of the clinical data of the main studies evaluating therapies for smoking cessation within COPD starting with the seminal Lung Health Study and continuing with more recent ones.Expert opinion: Smoking cessation is one of the most difficult therapeutic interventions in COPD, despite having the highest impact on disease progression and despite the demonstrated benefit of the discussed pharmacological therapies. Potential approaches to maximize its chance of success might be represented by prolonging the time of administration, combinational options, or sequential pharmacotherapy.

A feasibility study with embedded pilot randomised controlled trial and process evaluation of electronic cigarettes for smoking cessation in patients with periodontitis

Background

Tobacco smoking is a major risk factor for several oral diseases, including periodontitis, and electronic cigarettes (e-cigarettes) are increasingly being used for smoking cessation. This study aimed to assess the viability of delivering and evaluating an e-cigarette intervention for smoking cessation within the dental setting, prior to a definitive study.

Methods

A feasibility study, comprising a pilot randomised controlled trial and qualitative process evaluation, was conducted over 22 months in the Newcastle upon Tyne Hospitals NHS Dental Clinical Research Facility, UK. The pilot trial comprised a two-armed, parallel group, individually randomised, controlled trial, with 1:1 allocation. Participant eligibility criteria included being a tobacco smoker, having periodontitis and not currently using an e-cigarette. All participants received standard non-surgical periodontal therapies and brief smoking cessation advice. The intervention group additionally received an e-cigarette starter kit with brief training. Proposed outcomes for a future definitive trial, in terms of smoking behaviour and periodontal/oral health, were collected over 6 months to assess data yield and quality and estimates of parameters. Analyses were descriptive, with 95% confidence intervals presented, where appropriate.

Results

Eighty participants were successfully recruited from a range of dental settings. Participant retention was 73% (n = 58; 95% CI 62–81%) at 6 months. The e-cigarette intervention was well received, with usage rates of 90% (n = 36; 95% CI 77–96%) at quit date. Twenty percent (n = 8; 95% CI 11–35%) of participants in the control group used an e-cigarette at some point during the study (against advice). The majority of the outcome measures were successfully collected, apart from a weekly smoking questionnaire (only 30% of participants achieved ≥ 80% completion). Reductions in expired air carbon monoxide over 6 months of 6 ppm (95% CI 1–10 ppm) and 12 ppm (95% CI 8–16 ppm) were observed in the control and intervention groups, respectively. Rates of abstinence (carbon monoxide-verified continuous abstinence for 6 months) for the two groups were 5% (n = 2; 95% CI 1–17%; control group) and 15% (n = 6; 95% CI 7–29%; intervention group).

Conclusions

Data suggest that a definitive trial is feasible and that the intervention may improve smoking quit rates. Insights were gained into how best to conduct the definitive trial and estimates of parameters to inform design were obtained.

Trial registration

ISRCTN, ISRCTN17731903; registered 19 September 2016 http://www.isrctn.com/ISRCTN17731903.

Electronic supplementary material

The online version of this article (10.1186/s40814-019-0451-4) contains supplementary material, which is available to authorized users.

Different doses, durations and modes of delivery of nicotine replacement therapy for smoking cessation

BACKGROUND

Nicotine replacement therapy (NRT) aims to replace nicotine from cigarettes to ease the transition from cigarette smoking to abstinence. It works by reducing the intensity of craving and withdrawal symptoms. Although there is clear evidence that NRT used after smoking cessation is effective, it is unclear whether higher doses, longer durations of treatment, or using NRT before cessation add to its effectiveness.

OBJECTIVES

To determine the effectiveness and safety of different forms, deliveries, doses, durations and schedules of NRT, for achieving long-term smoking cessation, compared to one another.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group trials register, and trial registries for papers mentioning NRT in the title, abstract or keywords. Date of most recent search: April 2018.

SELECTION CRITERIA

Randomized trials in people motivated to quit, comparing one type of NRT use with another. We excluded trials that did not assess cessation as an outcome, with follow-up less than six months, and with additional intervention components not matched between arms. Trials comparing NRT to control, and trials comparing NRT to other pharmacotherapies, are covered elsewhere.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods. Smoking abstinence was measured after at least six months, using the most rigorous definition available. We extracted data on cardiac adverse events (AEs), serious adverse events (SAEs), and study withdrawals due to treatment. We calculated the risk ratio (RR) and the 95% confidence interval (CI) for each outcome for each study, where possible. We grouped eligible studies according to the type of comparison. We carried out meta-analyses where appropriate, using a Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We identified 63 trials with 41,509 participants. Most recruited adults either from the community or from healthcare clinics. People enrolled in the studies typically smoked at least 15 cigarettes a day. We judged 24 of the 63 studies to be at high risk of bias, but restricting the analysis only to those studies at low or unclear risk of bias did not significantly alter results, apart from in the case of the preloading comparison. There is high-certainty evidence that combination NRT (fast-acting form + patch) results in higher long-term quit rates than single form (RR 1.25, 95% CI 1.15 to 1.36, 14 studies, 11,356 participants; I² = 4%). Moderate-certainty evidence, limited by imprecision, indicates that 42/44 mg are as effective as 21/22 mg (24-hour) patches (RR 1.09, 95% CI 0.93 to 1.29, 5 studies, 1655 participants; I² = 38%), and that 21 mg are more effective than 14 mg (24-hour) patches (RR 1.48, 95% CI 1.06 to 2.08, 1 study, 537 participants). Moderate-certainty evidence (again limited by imprecision) also suggests a benefit of 25 mg over 15 mg (16-hour) patches, but the lower limit of the CI encompassed no difference (RR 1.19, 95% CI 1.00 to 1.41, 3 studies, 3446 participants; I² = 0%). Five studies comparing 4 mg gum to 2 mg gum found a benefit of the higher dose (RR 1.43, 95% CI 1.12 to 1.83, 5 studies, 856 participants; I² = 63%); however, results of a subgroup analysis suggest that only smokers who are highly dependent may benefit. Nine studies tested the effect of using NRT prior to quit day (preloading) in comparison to using it from quit day onward; there was moderate-certainty evidence, limited by risk of bias, of a favourable effect of preloading on abstinence (RR 1.25, 95% CI 1.08 to 1.44, 9 studies, 4395 participants; I² = 0%). High-certainty evidence from eight studies suggests that using either a form of fast-acting NRT or a nicotine patch results in similar long-term quit rates (RR 0.90, 95% CI 0.77 to 1.05, 8 studies, 3319 participants; I² = 0%). We found no evidence of an effect of duration of nicotine patch use (low-certainty evidence); 16-hour versus 24-hour daily patch use; duration of combination NRT use (low- and very low-certainty evidence); tapering of patch dose versus abrupt patch cessation; fast-acting NRT type (very low-certainty evidence); duration of nicotine gum use; ad lib versus fixed dosing of fast-acting NRT; free versus purchased NRT; length of provision of free NRT; ceasing versus continuing patch use on lapse; and participant- versus clinician-selected NRT. However, in most cases these findings are based on very low- or low-certainty evidence, and are the findings from single studies.AEs, SAEs and withdrawals due to treatment were all measured variably and infrequently across studies, resulting in low- or very low-certainty evidence for all comparisons. Most comparisons found no evidence of an effect on cardiac AEs, SAEs or withdrawals. Rates of these were low overall. Significantly more withdrawals due to treatment were reported in participants using nasal spray in comparison to patch in one trial (RR 3.47, 95% CI 1.15 to 10.46, 922 participants; very low certainty) and in participants using 42/44 mg patches in comparison to 21/22 mg patches across two trials (RR 4.99, 95% CI 1.60 to 15.50, 2 studies, 544 participants; I² = 0%; low certainty).

AUTHORS' CONCLUSIONS

There is high-certainty evidence that using combination NRT versus single-form NRT, and 4 mg versus 2 mg nicotine gum, can increase the chances of successfully stopping smoking. For patch dose comparisons, evidence was of moderate certainty, due to imprecision. Twenty-one mg patches resulted in higher quit rates than 14 mg (24-hour) patches, and using 25 mg patches resulted in higher quit rates than using 15 mg (16-hour) patches, although in the latter case the CI included one. There was no clear evidence of superiority for 42/44 mg over 21/22 mg (24-hour) patches. Using a fast-acting form of NRT, such as gum or lozenge, resulted in similar quit rates to nicotine patches. There is moderate-certainty evidence that using NRT prior to quitting may improve quit rates versus using it from quit date only; however, further research is needed to ensure the robustness of this finding. Evidence for the comparative safety and tolerability of different types of NRT use is of low and very low certainty. New studies should ensure that AEs, SAEs and withdrawals due to treatment are both measured and reported.

Nicotine preloading for smoking cessation: the Preloading RCT

BACKGROUND

Nicotine preloading means using nicotine replacement therapy prior to a quit date while smoking normally. The aim is to reduce the drive to smoke, thereby reducing cravings for smoking after quit day, which are the main cause of early relapse. A prior systematic review showed inconclusive and heterogeneous evidence that preloading was effective and little evidence of the mechanism of action, with no cost-effectiveness data.

OBJECTIVES

To assess (1) the effectiveness, safety and tolerability of nicotine preloading in a routine NHS setting relative to usual care, (2) the mechanisms of the action of preloading and (3) the cost-effectiveness of preloading.

DESIGN

Open-label randomised controlled trial with examination of mediation and a cost-effectiveness analysis.

SETTING

NHS smoking cessation clinics.

PARTICIPANTS

People seeking help to stop smoking.

INTERVENTIONS

Nicotine preloading comprised wearing a 21 mg/24 hour nicotine patch for 4 weeks prior to quit date. In addition, minimal behavioural support was provided to explain the intervention rationale and to support adherence. In the comparator group, participants received equivalent behavioural support. Randomisation was stratified by centre and concealed from investigators.

MAIN OUTCOME MEASURES

The primary outcome was 6-month prolonged abstinence assessed using the Russell Standard. The secondary outcomes were 4-week and 12-month abstinence. Adverse events (AEs) were assessed from baseline to 1 week after quit day. In a planned analysis, we adjusted for the use of varenicline (Champix^®; Pfizer Inc., New York, NY, USA) as post-cessation medication. Cost-effectiveness analysis took a health-service perspective. The within-trial analysis assessed health-service costs during the 13 months of trial enrolment relative to the previous 6 months comparing trial arms. The base case was based on multiple imputation for missing cost data. We modelled long-term health outcomes of smoking-related diseases using the European-study on Quantifying Utility of Investment in Protection from Tobacco (EQUIPT) model.

RESULTS

In total, 1792 people were eligible and were enrolled in the study, with 893 randomised to the control group and 899 randomised to the intervention group. In the intervention group, 49 (5.5%) people discontinued preloading prematurely and most others used it daily. The primary outcome, biochemically validated 6-month abstinence, was achieved by 157 (17.5%) people in the intervention group and 129 (14.4%) people in the control group, a difference of 3.02 percentage points [95% confidence interval (CI) -0.37 to 6.41 percentage points; odds ratio (OR) 1.25, 95% CI 0.97 to 1.62; p = 0.081]. Adjusted for use of post-quit day varenicline, the OR was 1.34 (95% CI 1.03 to 1.73; p = 0.028). Secondary abstinence outcomes were similar. The OR for the occurrence of serious AEs was 1.12 (95% CI 0.42 to 3.03). Moderate-severity nausea occurred in an additional 4% of the preloading group compared with the control group. There was evidence that reduced urges to smoke and reduced smoke inhalation mediated the effect of preloading on abstinence. The incremental cost-effectiveness ratio at the 6-month follow-up for preloading relative to control was £710 (95% CI -£13,674 to £23,205), but preloading was dominant at 12 months and in the long term, with an 80% probability that it is cost saving.

LIMITATIONS

The open-label design could partially account for the mediation results. Outcome assessment could not be blinded but was biochemically verified.

CONCLUSIONS

Use of nicotine-patch preloading for 4 weeks prior to attempting to stop smoking can increase the proportion of people who stop successfully, but its benefit is undermined because it reduces the use of varenicline after preloading. If this latter effect could be overcome, then nicotine preloading appears to improve health and reduce health-service costs in the long term. Future work should determine how to ensure that people using nicotine preloading opt to use varenicline as cessation medication.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN33031001.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 41. See the NIHR Journals Library website for further project information.

Effects of time-varying changes in tobacco and alcohol use on depressive symptoms following pharmaco-behavioral treatment for smoking and heavy drinking

BACKGROUND

Complete abstinence from alcohol as well as smoking cessation have been shown to predict reductions in depressive symptoms over time. However, whether reducing alcohol use or smoking positively affect depressive symptoms has yet to be examined. The current study examined depressive symptoms as a function of time-varying changes in alcohol use and smoking status following a pharmaco-behavioral treatment addressing smoking cessation and alcohol reduction.

METHODS

Participants were heavy-drinking smokers (n = 150) followed for 26 weeks after their quit smoking date, with assessments of smoking, alcohol use, and depressive symptoms at baseline and 2, 8, 16, and 26 weeks.

RESULTS

Abstinence from smoking was associated with significantly lower depressive symptoms, as compared to little to no reduction in smoking (B = -6.1) as well as significant reductions in smoking (B = 4.01). Exploratory analyses, which excluded observations in which a participant was abstinent, revealed a significant effect of percent change in cigarettes smoked, modeled continuously, on depressive symptoms, (B = 4.39). By contrast, no differences were observed in depressive symptoms in relation to changes in alcohol use.

CONCLUSION

It appears that smoking abstinence is associated with improvements in depression as compared to any level of sustained or reduced use and that the magnitude of smoking reduction may be associated with lower depressive symptoms among those who did not quit successfully. If replicated, these findings may inform treatment for individuals for whom depression is a major barrier to cessation and who have been unable or are unwilling to be completely abstinent from smoking.

Mediators of the effect of nicotine pre-treatment on quitting smoking

BACKGROUND AND AIMS

Using smoking cessation medications for several weeks prior to quitting smoking facilitates quitting success, but how it does so is not clear. Candidate theories are that pre-cessation medication enhances self-efficacy, facilitates medication adherence post-quit, induces aversion to smoking, reduces reward from smoking or reduces the drive to smoke. We investigated these pathways using data from a large trial of nicotine pre-loading, using mediation analysis.

DESIGN

Randomized controlled trial of nicotine pre-loading. Potential mediators were assessed at baseline and 1 week into the pre-loading (3 weeks prior to quitting). In addition to this, urges to smoke in abstainers were assessed 1 week after the target quit date.

SETTING

England.

PARTICIPANTS

A total of 1792 smokers who wanted to quit attending specialist smoking cessation services in England were enrolled between 13 August 2012 and 10 March 2015.

INTERVENTION AND COMPARATOR

Participants were randomized to either standard smoking cessation medications accompanied by behavioural support or the same treatment supplemented by nicotine 'pre-loading', i.e. 4 weeks of 21 mg nicotine patch use prior to quitting.

MEASUREMENTS

The primary outcome, selected for its proximity in time to potential mediators, was biochemically validated abstinence from smoking at 4 weeks post-target quit date. Potential mediators included the Modified Cigarette Evaluation Questionnaire, with subscales assessing satisfaction, reward, craving and aversion; ratings of strength and frequency of urges to smoke; the Mood and Physical Symptoms Scale assessing cigarette withdrawal symptoms; two items from the Nicotine Dependence Syndrome Scale assessing smoking stereotypy; self-reported reduction in cigarettes per day and in carbon monoxide (CO) reading; post-target quit day (TQD) medication adherence; self-efficacy; nausea.

FINDINGS

Pre-loading reduced urges to smoke at 3 weeks pre-quit (P < 0.001) and exhaled CO concentrations (P < 0.001), and also urges to smoke post-quit in abstainers (P = 0.001). At 3 weeks pre-quit, it also reduced cigarette consumption, enjoyment of and satisfaction from smoking and smoking reward and increased nausea, aversion (all P < 0.001) and smoking stereotypy (P = 0.003). Only the first three variables, however (reduced smoke intake and reduced urges to smoke pre- and post-quit), mediated abstinence from smoking at 4 weeks and only the latter two mediated abstinence at 6 months (indirect mediating effects P < 0.05).

CONCLUSIONS

Nicotine pre-loading appears to facilitate smoking abstinence by reducing urges to smoke and smoke intake before quitting and urges to smoke after quitting.

A Randomized Clinical Trial of Nicotine Preloading for Smoking Cessation in People with Posttraumatic Stress Disorder

OBJECTIVE

The aim of this research was to determine whether augmenting standard smoking cessation treatment by wearing an active nicotine patch before the smoking quit date improves rates of smoking cessation in individuals with posttraumatic stress disorder (PTSD) and to explore mechanisms of treatment response such as decreased cigarette craving and symptom relief from smoking.

METHODS

This was a double-blind parallel randomized controlled trial in 81 people with PTSD who smoked cigarettes. Participants were recruited from Veterans Affairs outpatient clinics and flyers in the community. Participants provided ecological momentary assessments (EMAs) of PTSD symptoms, smoking withdrawal symptoms, and cravings before and after smoking a cigarette during one week of ad lib smoking and then three weeks of either a nicotine patch (n = 37) or placebo patch (n = 44) preceding the quit date. All participants received standard pharmacotherapy and behavioral treatment for smoking cessation after the quit date. To test the efficacy of nicotine patch preloading for engaging proposed treatment targets during the pre-quit phases, we used multilevel models to compare post-smoking changes in symptoms and cravings during the preloading phases to post-smoking changes reported during the ad lib smoking phase.

RESULTS

There was no significant difference in quit rates across the two conditions on the primary outcome of seven-day point prevalence smoking abstinence bioverified with breath carbon monoxide at six weeks post-quit date. In a multivariable multilevel model pre- to post-cigarette changes in PTSD symptom clusters, smoking withdrawal symptoms, and cravings, there was a significant interaction between treatment phase and condition. Relative to participants in the placebo condition, participants in the nicotine patch condition experienced diminished relief from PTSD reexperiencing symptoms, smoking withdrawal symptoms, and cigarette craving after smoking a cigarette.

CONCLUSIONS

Relative to placebo patch preloading, nicotine patch preloading diminished the reinforcing effects of smoking cigarettes. However, the low quit rates in both conditions suggest that nicotine patch preloading is not a sufficiently intensive treatment for achieving smoking cessation in people with PTSD.

TRIAL REGISTRATION

clinicaltrials.gov: NCT00625131.

Effects on abstinence of nicotine patch treatment before quitting smoking: parallel, two arm, pragmatic randomised trial

OBJECTIVE

To examine the effectiveness of a nicotine patch worn for four weeks before a quit attempt.

DESIGN

Randomised controlled open label trial.

SETTING

Primary care and smoking cessation clinics in England, 2012-15.

PARTICIPANTS

1792 adults who were daily smokers with tobacco dependence. 899 were allocated to the preloading arm and 893 to the control arm.

INTERVENTIONS

Participants were randomised 1:1, using concealed randomly permuted blocks stratified by centre, to either standard smoking cessation pharmacotherapy and behavioural support or the same treatment supplemented by four weeks of 21 mg nicotine patch use before quitting: "preloading."

MAIN OUTCOME MEASURES

The primary outcome was biochemically confirmed prolonged abstinence at six months. Secondary outcomes were prolonged abstinence at four weeks and 12 months.

RESULTS

Biochemically validated abstinence at six months was achieved by 157/899 (17.5%) participants in the preloading arm and 129/893 (14.4%) in the control arm: difference 3.0% (95% confidence interval -0.4% to 6.4%), odds ratio 1.25 (95% confidence interval 0.97 to 1.62), P=0.08 in the primary analysis. There was an imbalance between arms in the frequency of varenicline use as post-cessation treatment, and planned adjustment for this gave an odds ratio for the effect of preloading of 1.34 (95% confidence interval 1.03 to 1.73), P=0.03: difference 3.8% (0.4% to 7.2%). At four weeks, the difference in prolonged abstinence unadjusted for varenicline use was odds ratio 1.21 (1.00 to 1.48), difference 4.3% (0.0% to 8.7%), P=0.05, and adjusted for varenicline use was 1.32 (1.08 to 1.62) P=0.007. At 12 months the odds ratio was 1.28 (0.97 to 1.69), difference 2.7% (-0.4% to 5.8%), P=0.09 unadjusted for varenicline use and after adjustment was 1.36 (1.02 to 1.80) P=0.04. 5.9% of participants discontinued preloading owing to intolerance. Gastrointestinal symptoms-chiefly nausea-occurred in 4.0% (2.2% to 5.9%) more people in the preloading arm than control arm. Eight serious adverse events occurred in the preloading arm and eight in the control arm (odds ratio 0.99, 0.36 to 2.75).

CONCLUSIONS

Evidence was insufficient to confidently show that nicotine preloading increases subsequent smoking abstinence. The beneficial effect seems to have been masked by a concurrent reduction in the use of varenicline in people using nicotine preloading, and future studies should explore ways to mitigate this unintended effect.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN33031001.