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

Age-period-cohort effects of adult cigarette smoking in the united States, 1971-2020

The rates of cigarette use among American adults have dropped substantially throughout the last six decades, yet smoking remains the leading cause of preventable disease and death in the United States. It is crucial to identify the putative time-varying population-level factors of age, period, and cohort that influenced the decrease in smoking prevalence so we can maintain the downward trend. We used 49 years of data from the National Health and Nutrition Examination Survey (NHANES) and hierarchical age-period-cohort (HAPC) analysis to examine lifecycle, historical, and generational distribution of smoking among Americans aged 18-74 years old. The prevalence of smoking has declined tremendously from 1971 to 2020 because American adults over the age of ~ 27 had a lower probability of cigarette use, but the rates of decrease have been unequal among birth cohorts. We uncovered the putative temporal contributors to population-level decreases in the prevalence of current smoking among American adults over the last nearly fifty years. Policy-makers ought to prioritize tobacco control efforts that focus on young adults, and should address the cohort-specific challenges in order to maintain the downward trend in smoking prevalence and further reduce the number of preventable premature deaths due to cigarette use.

Oral health effects of non-combustible nicotine products: protocol for a systematic review and network meta-analysis

BACKGROUND

Tobacco use is a global issue, and non-combustible nicotine products (NCNPs) like electronic nicotine delivery systems, nicotine pouches, snus, and nicotine replacement therapies offer potential risk/harm reduction for smokers unable or unwilling to quit. Although NCNPs are less harmful than tobacco smoking, their impact on oral health remains unclear. A systematic review and network meta-analysis will be conducted to answer the research question: What are the oral signs and symptoms associated with NCNPs as both monotherapies and combination therapies compared to each other, placebo, standard care, no drug treatment, and combustible cigarette smoking?

METHODS

We will search PubMed and Scopus databases, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to August 2024. This review will focus on randomized controlled trials (RCTs) with a minimum follow-up period of 1 month, comparing any NCNPs versus placebo, standard care, no drug treatment, combustible cigarette smoking or to each other in adult smokers. Our primary outcomes will be the number of participants reporting any oral side effect, aphthous ulcers, dry mouth and mouth irritation. Studies will be excluded if they involve: non-smokers, pregnant women, individuals with mental health or neurological disorders, participants consuming alcohol or other substances. Data will be analyzed using a network meta-analysis framework, estimating odds ratios with 95% confidence intervals. Risk of bias will be determined using the Cochrane risk of bias tool-version 2.0 for included RCTs and the Confidence In Network Meta-Analysis tool will be employed to assess the confidence of evidence contributing to each network estimate.

DISCUSSION

Our findings will provide critical insights into the oral health implications of NCNPs, informing clinical and public health decisions. Results are expected by May 2025 and will be disseminated through publications and presentations to guide tobacco harm reduction strategies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42024565118.

Interventions for smokeless tobacco use cessation

RATIONALE

While combustible tobacco has been the subject of a very large amount of research, smokeless tobacco products receive less attention. Most smokeless tobacco products are very harmful and cause global health inequality. It is therefore important to identify evidence-based cessation aids.

OBJECTIVES

To assess the effects of behavioural and pharmacological interventions for smokeless tobacco use cessation.

SEARCH METHODS

We searched the following databases from inception to 16 February 2024: Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; Embase; PsycINFO; ClinicalTrials.gov (through CENTRAL); World Health Organisation International Clinical Trials Registry Platform (through CENTRAL). We also searched references of eligible studies.

ELIGIBILITY CRITERIA

We included randomised controlled trials (RCTs) recruiting people of any age using smokeless tobacco, regardless of tobacco smoking status. Eligible studies could test any intervention designed to support people to quit smokeless tobacco use, and had to measure abstinence from either all tobacco use or smokeless tobacco use at six months or longer.

OUTCOMES

The outcome of interest was abstinence from all tobacco use or from smokeless tobacco use at six months or longer.

RISK OF BIAS

We used the Cochrane RoB 1 tool to assess bias in included studies.

SYNTHESIS METHODS

We followed standard Cochrane methods for screening and data extraction. We grouped studies by comparisons of eligible interventions and comparators, reporting individual study and pooled effects as appropriate. We used a random-effects Mantel-Haenszel model for analyses of behavioural interventions and a fixed effect Mantel-Haenszel model for analyses of pharmacotherapies to calculate risk ratios (RR) with 95% confidence intervals (CI). We assessed the certainty of evidence using GRADE.

INCLUDED STUDIES

We included 43 trials of 20,346 people. Thirty-three trials were conducted in North America, five in India, two in Scandinavia, one in Pakistan and one in Turkey. One study was conducted across multiple sites in Bangladesh, India and Pakistan. Studies tested behavioural interventions (e.g. cessation counselling and brief advice) and pharmacotherapies (e.g. nicotine replacement therapy (NRT), varenicline, and bupropion). We judged five studies to be at low risk of bias overall, 22 at high risk of bias, and the remaining 16 at unclear risk of bias.

SYNTHESIS OF RESULTS

We found moderate-certainty evidence of increased quit rates from counselling compared with minimal support (RR 1.76, 95% CI 1.44 to 2.16; I2 = 69%; 21 studies, n = 7417; downgraded because of heterogeneity), brief advice compared with no support (RR 1.24, 95% CI 1.03 to 1.48; I2 = 49%; 7 studies, n = 6271; downgraded because of imprecision), and varenicline compared with placebo (RR 1.35, 95% CI 1.08 to 1.68; I2 = 0%; 2 studies, n = 508; downgraded because of imprecision). We found low-certainty evidence (downgraded because of imprecision and risk of bias) of increased quit rates from NRT compared with placebo or no medication (RR 1.18, 95% CI 1.05 to 1.33; I2 = 39%; 11 studies, n = 2826). Low-certainty evidence (downgraded because of imprecision) did not show benefit from bupropion compared with placebo (RR 0.89, 95% CI 0.54 to 1.44; I2 = 0%; 2 studies, n = 293). We planned subgroup analyses to explore whether smokeless tobacco type affects intervention efficacy, but found insufficient data.

AUTHORS' CONCLUSIONS

Cessation counselling, brief advice, and varenicline each probably help more people to quit smokeless tobacco use than minimal or no support, or placebo. NRT may help more people to quit smokeless tobacco use than placebo or no medication. Low-certainty evidence does not currently support bupropion as a smokeless tobacco cessation intervention. Despite the majority of smokeless tobacco users living in South and Southeast Asia, only a minority of trials are conducted in those regions. Future trials should address this imbalance.

FUNDING

None REGISTRATION: Protocol available via DOI: 10.1002/14651858.CD015314.

Global research trends and emerging hotspots in acute high altitude illness: a bibliometric analysis and review (1937-2024)

INTRODUCTION

Acute High Altitude Illness (AHAI) includes conditions such as Acute Mountain Sickness (AMS), High Altitude Cerebral Edema (HACE), and High Altitude Pulmonary Edema (HAPE), which result from rapid ascent to altitudes exceeding 2,500 m. Although interest in AHAI research has been growing, a systematic and comprehensive analysis of global research trends remains lacking.

CONTENT

A total of 3,214 articles and reviews published from 1937 to 2024 were retrieved from the Web of Science Core Collection. Bibliometric tools, including CiteSpace and VOSviewer, were applied to thoroughly assess publication trends, collaborative networks among authors, institutional contributions, and keyword co-occurrence patterns. The dataset represents the contributions of over 11,758 authors across 86 countries and 3,378 institutions, reflecting the significant growth of this research domain.

SUMMARY AND OUTLOOK

Our findings highlight the increasing scholarly attention to AHAI research, with the United States leading in publication numbers. Emerging research themes include cellular activation, oxidative stress, risk factors, and hypobaric hypoxia. This is the first systematic bibliometric review of AHAI literature, offering a detailed roadmap of research hotspots, potential collaborations, and key future directions. These findings provide a valuable reference for researchers aiming to explore gaps and build on the existing knowledge in high-altitude medicine.

Smoking Cessation Strategies After Acute Coronary Syndrome

Smoking is one of the strongest modifiable risk factors for coronary artery disease. It is the cause of approximately 10-30% of deaths due to cardiovascular disease around the world. There is a 50% reduction in the risk of myocardial infarction by one year for people who successfully quit smoking. Considering the risk associated with smoking and the benefits of smoking cessation, it is important to identify and implement effective smoking cessation strategies. There are pharmacological as well as non-pharmacological interventions to assist in smoking cessation. Pharmacological therapies including nicotine replacement therapy; bupropion and varenicline have generally been studied more in patients with cardiovascular disease than the non-pharmacological interventions. Non-pharmacological strategies for smoking cessation include behavioural interventions such as counselling sessions and cognitive behavioural therapy. Studies and randomised controlled trials have demonstrated the safety of most of the pharmacological interventions. Nonetheless, the success rates are variable for the different pharmacological options. Data suggest that greater success can be achieved in smoking cessation with a combination of pharmacological and non-pharmacological treatment. However, more studies are needed to explore the best therapeutic options to improve the success of smoking cessation.

Electronic cigarettes for smoking cessation

BACKGROUND

Electronic cigarettes (ECs) are handheld electronic vaping devices that produce an aerosol by heating an e-liquid. People who smoke, healthcare providers, and regulators want to know if ECs can help people quit smoking, and if they are safe to use for this purpose. This is a review update conducted as part of a living systematic review.

OBJECTIVES

To examine the safety, tolerability, and effectiveness of using EC to help people who smoke tobacco achieve long-term smoking abstinence, in comparison to non-nicotine EC, other smoking cessation treatments, and no treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 February 2024 and the Cochrane Tobacco Addiction Group's Specialized Register to 1 February 2023, reference-checked, and contacted study authors.

SELECTION CRITERIA

We included trials randomizing people who smoke to an EC or control condition. We included uncontrolled intervention studies in which all participants received an EC intervention. Studies had to report an eligible outcome.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods for screening and data extraction. We used the risk of bias tool (RoB 1) and GRADE to assess the certainty of evidence. Critical outcomes were abstinence from smoking after at least six months, adverse events (AEs), and serious adverse events (SAEs). Important outcomes were biomarkers, toxicants/carcinogens, and longer-term EC use. We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in pairwise and network meta-analyses (NMA).

MAIN RESULTS

We included 90 completed studies (two new to this update), representing 29,044 participants, of which 49 were randomized controlled trials (RCTs). Of the included studies, we rated 10 (all but one contributing to our main comparisons) at low risk of bias overall, 61 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. Nicotine EC results in increased quit rates compared to nicotine replacement therapy (NRT) (high-certainty evidence) (RR 1.59, 95% CI 1.30 to 1.93; I2 = 0%; 7 studies, 2544 participants). In absolute terms, this might translate to an additional four quitters per 100 (95% CI 2 to 6 more). The rate of occurrence of AEs is probably similar between groups (moderate-certainty evidence (limited by imprecision)) (RR 1.03, 95% CI 0.91 to 1.17; I2 = 0%; 5 studies, 2052 participants). SAEs were rare, and there is insufficient evidence to determine whether rates differ between groups due to very serious imprecision (RR 1.20, 95% CI 0.90 to 1.60; I2 = 32%; 6 studies, 2761 participants; low-certainty evidence). Nicotine EC probably results in increased quit rates compared to non-nicotine EC (moderate-certainty evidence, limited by imprecision) (RR 1.46, 95% CI 1.09 to 1.96; I2 = 4%; 6 studies, 1613 participants). In absolute terms, this might lead to an additional three quitters per 100 (95% CI 1 to 7 more). There is probably little to no difference in the rate of AEs between these groups (moderate-certainty evidence) (RR 1.01, 95% CI 0.91 to 1.11; I2 = 0%; 5 studies, 840 participants). There is insufficient evidence to determine whether rates of SAEs differ between groups, due to very serious imprecision (RR 1.00, 95% CI 0.56 to 1.79; I2 = 0%; 9 studies, 1412 participants; low-certainty evidence). Compared to behavioural support only/no support, quit rates may be higher for participants randomized to nicotine EC (low-certainty evidence due to issues with risk of bias) (RR 1.96, 95% CI 1.66 to 2.32; I2 = 0%; 11 studies, 6819 participants). In absolute terms, this represents an additional four quitters per 100 (95% CI 3 to 5 more). There was some evidence that (non-serious) AEs may be more common in people randomized to nicotine EC (RR 1.18, 95% CI 1.10 to 1.27; I2 = 6%; low-certainty evidence; 6 studies, 2351 participants) and, again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 0.93, 95% CI 0.68 to 1.28; I2 = 0%; 12 studies, 4561 participants; very low-certainty evidence). Results from the NMA were consistent with those from pairwise meta-analyses for all critical outcomes. There was inconsistency in the AE network, which was explained by a single outlying study contributing the only direct evidence for one of the nodes. Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued EC use. Very few studies reported data on other outcomes or comparisons; hence, evidence for these is limited, with CIs often encompassing both clinically significant harm and benefit.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that ECs with nicotine increase quit rates compared to NRT and moderate-certainty evidence that they increase quit rates compared to ECs without nicotine. Evidence comparing nicotine EC with usual care or no treatment also suggests benefit, but is less certain due to risk of bias inherent in the study design. Confidence intervals were, for the most part, wide for data on AEs, SAEs, and other safety markers, with no evidence for a difference in AEs between nicotine and non-nicotine ECs nor between nicotine ECs and NRT, but low-certainty evidence for increased AEs compared with behavioural support/no support. Overall incidence of SAEs was low across all study arms. We did not detect evidence of serious harm from nicotine EC, but longer, larger studies are needed to fully evaluate EC safety. Our included studies tested regulated nicotine-containing EC; illicit products and/or products containing other active substances (e.g. tetrahydrocannabinol (THC)) may have different harm profiles. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates. Further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this is a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.

Differences in the effectiveness of individual-level smoking cessation interventions by socioeconomic status

BACKGROUND

People from lower socioeconomic groups are more likely to smoke and less likely to succeed in achieving abstinence, making tobacco smoking a leading driver of health inequalities. Contextual factors affecting subpopulations may moderate the efficacy of individual-level smoking cessation interventions. It is not known whether any intervention performs differently across socioeconomically-diverse populations and contexts.

OBJECTIVES

To assess whether the effects of individual-level smoking cessation interventions on combustible tobacco cigarette use differ by socioeconomic groups, and their potential impact on health equalities.

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews from inception to 1 May 2023 for Cochrane reviews investigating individual-level smoking cessation interventions. We selected studies included in these reviews that met our criteria. We contacted study authors to identify further eligible studies.

SELECTION CRITERIA

We included parallel, cluster or factorial randomised controlled trials (RCTs) investigating any individual-level smoking cessation intervention which encouraged complete cessation of combustible tobacco cigarette use compared to no intervention, placebo, or another intervention in adults. Studies must have assessed or reported smoking quit rates, split by any measure of socioeconomic status (SES) at longest follow-up (≥ six months), and been published in 2000 or later.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods for screening, data extraction, and risk of bias assessment. We assessed the availability of smoking abstinence data by SES in lieu of selective reporting. The primary outcome was smoking cessation quit rates, split by lower and higher SES, at the longest follow-up (≥ six months). Where possible, we calculated ratios of odds ratios (ROR) with 95% confidence intervals (CIs) for each study, comparing lower to higher SES. We pooled RORs by intervention type in random-effects meta-analyses, using the generic inverse-variance method. We subgrouped by type of SES indicator and economic classification of the study country. We summarised all evidence in effect direction plots and categorised the intervention impact on health equality as: positive (evidence that the relative effect of the intervention on quit rates was greater in lower rather than higher SES groups), possibly positive, neutral, possibly neutral, possibly negative, negative, no reported statistically significant difference, or unclear. We evaluated certainty using GRADE.

MAIN RESULTS

We included 77 studies (73 from high-income countries), representing 127,791 participants. We deemed 12 studies at low overall risk of bias, 13 at unclear risk, and the remaining 52 at high risk. Included studies investigated a range of pharmacological interventions, behavioural support, or combinations of these. Pharmacological interventions We found very low-certainty evidence for all the main pharmacological interventions compared to control. Evidence on cytisine (ROR 1.13, 95% CI 0.73 to 1.74; 1 study, 2472 participants) and nicotine electronic cigarettes (ROR 4.57, 95% CI 0.88 to 23.72; 1 study, 989 participants) compared to control indicated a greater relative effect of these interventions on quit rates in lower compared to higher SES groups, suggesting a possibly positive impact on health equality. CIs for both estimates included the possibility of no clinically important difference and of favouring higher SES groups. There was a lower relative effect of bupropion versus placebo on quit rates in lower compared to higher SES groups, indicating a possibly negative impact on health equality (ROR 0.05, 95% CI 0.00 to 1.00; from 1 of 2 studies, 354 participants; 1 study reported no difference); however, the CI included the possibility of no clinically important difference. We could not determine the intervention impact of combination or single-form nicotine replacement therapy on relative quit rates by SES. No studies on varenicline versus control were included. Behavioural interventions We found low-certainty evidence of lower quit rates in lower compared to higher SES groups for print-based self-help (ROR 0.85, 95% CI 0.52 to 1.38; 3 studies, 4440 participants) and text-messaging (ROR 0.76, 95% CI 0.47 to 1.23; from 3 of 4 studies, 5339 participants; 1 study reported no difference) versus control, indicating a possibly negative impact on health equality. CIs for both estimates included the possibility of no clinically important difference and of favouring lower SES groups. There was very low-certainty evidence of quit rates favouring higher SES groups for financial incentives compared to balanced intervention components. However, the CI included the possibility of no clinically important difference and of favouring lower SES groups (ROR 0.91, 95% CI 0.45 to 1.85; from 5 of 6 studies, 3018 participants; 1 study reported no difference). This indicates a possibly negative impact on health equality. There was very low-certainty evidence of no difference in quit rates by SES for face-to-face counselling compared to less intensive counselling, balanced components, or usual care. However, the CI included the possibility of favouring lower and higher SES groups (ROR 1.26, 95% CI 0.18 to 8.93; from 1 of 6 studies, 294 participants; 5 studies reported no difference), indicating a possibly neutral impact. We found very low-certainty evidence of a greater relative effect of telephone counselling (ROR 4.31, 95% CI 1.28 to 14.51; from 1 of 7 studies, 903 participants; 5 studies reported no difference, 1 unclear) and internet interventions (ROR 1.49, 95% CI 0.99 to 2.25; from 1 of 5 studies, 4613 participants; 4 studies reported no difference) versus control on quit rates in lower versus higher SES groups, suggesting a possibly positive impact on health equality. The CI for the internet intervention estimate included the possibility of no difference. Although the CI for the telephone counselling estimate only favoured lower SES groups, most studies narratively reported no clear evidence of interaction effects.

AUTHORS' CONCLUSIONS

Currently, there is no clear evidence to support the use of differential individual-level smoking cessation interventions for people from lower or higher SES groups, or that any one intervention would have an effect on health inequalities. This conclusion may change as further data become available. Many studies did not report sufficient data to be included in a meta-analysis, despite having tested the association of interest. Further RCTs should collect, analyse, and report quit rates by measures of SES, to inform intervention development and ensure recommended interventions do not exacerbate but help reduce health inequalities caused by smoking.

Tobacco cessation: screening and interventions

BACKGROUND

Tobacco use has been the leading cause of disease and death in South Korea. Early detection of tobacco use and evidence-based interventions play pivotal roles in facilitating tobacco cessation.

METHODS

In accordance with the earlier iterations of the Lifetime Health Maintenance Program (2009) and recent recommendations from the United States Preventive Services Task Force (USPSTF; 2021), two themes were chosen for investigation: the identification of and intervention for tobacco use. The USPSTF recommendations were formulated by conducting an overview of reviews. In this study, literature searches and quality assessments of reviews were conducted.

RESULTS

The findings highlighted the efficacy of physician-led identification and advising in promoting tobacco cessation, with robust evidence supporting the implementation of behavioral and pharmacological interventions. These interventions significantly increased the likelihood of successful cessation compared with usual care. Digital interventions, such as internet- or mobile-based interventions, showed additive effects for quitting.

CONCLUSION

Identification and targeted interventions are essential for tobacco cessation. By leveraging evidencebased strategies and enhancing access to resources, healthcare providers can empower individuals to achieve successful tobacco cessation and improve overall health outcomes.

2024 Guideline for the Primary Prevention of Stroke: A Guideline From the American Heart Association/American Stroke Association

AIM

The "2024 Guideline for the Primary Prevention of Stroke" replaces the 2014 "Guidelines for the Primary Prevention of Stroke." This updated guideline is intended to be a resource for clinicians to use to guide various prevention strategies for individuals with no history of stroke.

METHODS

A comprehensive search for literature published since the 2014 guideline; derived from research involving human participants published in English; and indexed in MEDLINE, PubMed, Cochrane Library, and other selected and relevant databases was conducted between May and November 2023. Other documents on related subject matter previously published by the American Heart Association were also reviewed.

STRUCTURE

Ischemic and hemorrhagic strokes lead to significant disability but, most important, are preventable. The 2024 primary prevention of stroke guideline provides recommendations based on current evidence for strategies to prevent stroke throughout the life span. These recommendations align with the American Heart Association's Life's Essential 8 for optimizing cardiovascular and brain health, in addition to preventing incident stroke. We also have added sex-specific recommendations for screening and prevention of stroke, which are new compared with the 2014 guideline. Many recommendations for similar risk factor prevention were updated, new topics were reviewed, and recommendations were created when supported by sufficient-quality published data.

Effects of interventions to combat tobacco addiction: Cochrane update of 2021 to 2023 reviews

AIMS

To summarise systematic reviews on tobacco addiction published by the Cochrane Tobacco Addiction Group (CTAG) from 2021 to 2023.

METHODS

We identified all new and updated Cochrane Reviews published by CTAG between 2021 and 2023. We present key results from these reviews and discuss promising avenues for future research.

RESULTS

CTAG published five new reviews and one overview of reviews, and updated eight reviews. Review evidence showed that all main pharmacotherapies (varenicline, cytisine, bupropion and nicotine replacement therapy [NRT], especially when patches are combined with fast acting forms like gum) are effective for smoking cessation, as are nicotine e-cigarettes. Evidence suggested similar magnitude of effects of varenicline, cytisine, and nicotine e-cigarettes; these emerged as the most effective treatments. Evidence also supported behavioural counselling and financial incentives for smoking cessation. Secondary analyses of the Cochrane review of e-cigarettes for smoking cessation showed over half of participants assigned to e-cigarette conditions were still using them at six months or longer, that biomarkers of potential harm significantly reduced in people switching from smoking to vaping or to dual use, and that there was insufficient evidence to draw associations between e-liquid flavours and smoking cessation. Findings on mindfulness-based interventions, interventions delivered by dental and primary care professionals, interventions to prevent weight gain after smoking cessation, and interventions for waterpipe cessation were less certain. Reviews of observational evidence showed that smoking cessation reduced cardiovascular events and mortality in people living with cardiovascular disease, and improved mental health.

CONCLUSIONS

Nicotine replacement therapy (especially patches combined with fast acting forms), varenicline, cytisine, bupropion, nicotine e-cigarettes, behavioural counselling, and financial incentives are all effective ways to help people quit smoking. Quitting smoking improves mental health and reduces cardiovascular events and mortality in people living with cardiovascular disease.

Interventions for smoking cessation: An overview of Cochrane reviews

INTRODUCTION

Evidence of different smoking cessation interventions varies and has been assessed in many Cochrane reviews. We conducted an overview of these Cochrane reviews to summarize the effects of current interventions for smoking cessation.

METHODS

Nine databases were searched from their inception to October 2024, with no restrictions on language. Two authors independently extracted data from the same studies simultaneously, double checking after extraction. A second round of examination was conducted on all the extracted contents by another author. We employed a measurement tool to assess systematic reviews (AMSTAR-2) to evaluate the methodological rigor of the included systematic reviews (SRs), synthesized the GRADE results as reported, and conducted a narrative synthesis. The research protocol was registered on PROSPERO (CRD42023388884).

RESULTS

Seventy-one Cochrane reviews involving 3022 trials were included in this comprehensive analysis. The two predominant smoking cessation interventions were pharmacotherapy (24 SRs) and non-pharmacological therapy (31SRs). Overall, the methodological quality of all the reviews was good. Compared with placebo, the point effect size for each Cochrane review on relative risk (RR) regarding pharmacotherapies for prolonged abstinence rate ranged from 1.11 to 3.34, demonstrating high- or moderate-certainty evidence; whereas for non-pharmacological therapies, it varied from 0.79 to 25.38, but substantial heterogeneity was observed in most meta-analysis (I2>50%). Four studies investigating pharmacotherapies as interventions, adverse events were reported but no significant differences in outcomes were observed.

CONCLUSIONS

Pharmacotherapy demonstrated some efficacy in promoting prolonged abstinence rate, while the effectiveness of different non-pharmacological interventions for smoking cessation varied widely, highlighting the need for further research on the integration of pharmacotherapy and non-pharmacological therapies.

Interventions for tobacco use cessation in people living with HIV

BACKGROUND

The prevalence of tobacco use among people living with HIV (PLWH) is up to four times higher than in the general population. Unfortunately, tobacco use increases the risk of progression to AIDS and death. Individual- and group-level interventions, and system-change interventions that are effective in helping PLWH stop using tobacco can markedly improve the health and quality of life of this population. However, clear evidence to guide policy and practice is lacking, which hinders the integration of tobacco use cessation interventions into routine HIV care. This is an update of a review that was published in 2016. We include 11 new studies.

OBJECTIVES

To assess the benefits, harms and tolerability of interventions for tobacco use cessation among people living with HIV. To compare the benefits, harms and tolerability of interventions for tobacco use cessation that are tailored to the needs of people living with HIV with that of non-tailored cessation interventions.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group's Specialised Register, CENTRAL, MEDLINE, Embase, and PsycINFO in December 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of individual-/group-level behavioural or pharmacological interventions, or both, for tobacco use cessation, delivered directly to PLWH aged 18 years and over, who use tobacco. We also included RCTs, quasi-RCTs, other non-randomised controlled studies (e.g. controlled before and after studies), and interrupted time series studies of system-change interventions for tobacco use cessation among PLWH. For system-change interventions, participants could be PLWH receiving care, or staff working in healthcare settings and providing care to PLWH; but studies where intervention delivery was by research personnel were excluded. For both individual-/group-level interventions, and system-change interventions, any comparator was eligible.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods, and used GRADE to assess certainty of the evidence. The primary measure of benefit was tobacco use cessation at a minimum of six months. Primary measures for harm were adverse events (AEs) and serious adverse events (SAEs). We also measured quit attempts or quit episodes, the receipt of a tobacco use cessation intervention, quality of life, HIV viral load, CD4 count, and the incidence of opportunistic infections.

MAIN RESULTS

We identified 17 studies (16 RCTs and one non-randomised study) with a total of 9959 participants; 11 studies are new to this update. Nine studies contributed to meta-analyses (2741 participants). Fifteen studies evaluated individual-/group-level interventions, and two evaluated system-change interventions. Twelve studies were from the USA, two from Switzerland, and there were single studies for France, Russia and South Africa. All studies focused on cigarette smoking cessation. All studies received funding from independent national- or institutional-level funding. Three studies received study medication free of charge from a pharmaceutical company. Of the 16 RCTs, three were at low risk of bias overall, five were at high risk, and eight were at unclear risk. Behavioural support or system-change interventions versus no or less intensive behavioural support Low-certainty evidence (7 studies, 2314 participants) did not demonstrate a clear benefit for tobacco use cessation rates in PLWH randomised to receive behavioural support compared with brief advice or no intervention: risk ratio (RR) 1.11, 95% confidence interval (CI) 0.87 to 1.42, with no evidence of heterogeneity. Abstinence at six months or more was 10% (n = 108/1121) in the control group and 11% (n = 127/1193) in the intervention group. There was no evidence of an effect on tobacco use cessation on system-change interventions: calling the quitline and transferring the call to the patient whilst they are still in hospital ('warm handoff') versus fax referral (RR 3.18, 95% CI 0.76 to 13.99; 1 study, 25 participants; very low-certainty evidence). None of the studies in this comparison assessed SAE. Pharmacological interventions versus placebo, no intervention, or another pharmacotherapy Moderate-certainty evidence (2 studies, 427 participants) suggested that varenicline may help more PLWH to quit smoking than placebo (RR 1.95, 95% CI 1.05 to 3.62) with no evidence of heterogeneity. Abstinence at six months or more was 7% (n = 14/215) in the placebo control group and 13% (n = 27/212) in the varenicline group. There was no evidence of intervention effects from individual studies on behavioural support plus nicotine replacement therapy (NRT) versus brief advice (RR 8.00, 95% CI 0.51 to 126.67; 15 participants; very low-certainty evidence), behavioural support plus NRT versus behavioural support alone (RR 1.47, 95% CI 0.92 to 2.36; 560 participants; low-certainty evidence), varenicline versus NRT (RR 0.93, 95% CI 0.48 to 1.83; 200 participants; very low-certainty evidence), and cytisine versus NRT (RR 1.18, 95% CI 0.66 to 2.11; 200 participants; very low-certainty evidence). Low-certainty evidence (2 studies, 427 participants) did not detect a difference between varenicline and placebo in the proportion of participants experiencing SAEs (8% (n = 17/212) versus 7% (n = 15/215), respectively; RR 1.14, 95% CI 0.58 to 2.22) with no evidence of heterogeneity. Low-certainty evidence from one study indicated similar SAE rates between behavioural support plus NRT and behavioural support only (1.8% (n = 5/279) versus 1.4% (n = 4/281), respectively; RR 1.26, 95% CI 0.34 to 4.64). No studies assessed SAEs for the following: behavioural support plus NRT versus brief advice; varenicline versus NRT and cytisine versus NRT.

AUTHORS' CONCLUSIONS

There is no clear evidence to support or refute the use of behavioural support over brief advice, one type of behavioural support over another, behavioural support plus NRT over behavioural support alone or brief advice, varenicline over NRT, or cytisine over NRT for tobacco use cessation for six months or more among PLWH. Nor is there clear evidence to support or refute the use of system-change interventions such as warm handoff over fax referral, to increase tobacco use cessation or receipt of cessation interventions among PLWH who use tobacco. However, the results must be considered in the context of the small number of studies included. Varenicline likely helps PLWH to quit smoking for six months or more compared to control. We did not find evidence of difference in SAE rates between varenicline and placebo, although the certainty of the evidence is low.

The impact of smoking on bronchiectasis and its comorbidities

INTRODUCTION

Bronchiectasis, characterized by irreversible bronchial dilatation, is a growing global health concern with significant morbidity. This review delves into the intricate relationship between smoking and bronchiectasis, examining its epidemiology, pathophysiology, clinical manifestations, and therapeutic approaches. Our comprehensive literature search on PubMed utilized MESH terms including 'smoking,' 'smoking cessation,' 'bronchiectasis,' and 'comorbidities' to gather relevant studies.

AREAS COVERED

This review emphasizes the role of smoking in bronchiectasis development and exacerbation by compromising airways and immune function. Interconnected comorbidities, including chronic obstructive pulmonary disease, asthma, and gastroesophageal reflux disease, create a detrimental cycle affecting patient outcomes. Despite limited studies on smoking cessation in bronchiectasis, the review stresses its importance. Advocating for tailored cessation programs, interventions like drainage, bronchodilators, and targeted antibiotics are crucial to disrupting the inflammatory-infection-widening cycle.

EXPERT OPINION

The importance of smoking cessation in bronchiectasis management is paramount due to its extensive negative impact on related conditions. Proactive cessation programs utilizing technology and targeted education for high-risk groups aim to reduce smoking's impact on disease progression and related comorbidities. In conclusion, a personalized approach centered on smoking cessation is deemed vital for bronchiectasis, aiming to improve outcomes and enhance patients' quality of life in the face of this complex respiratory condition.

[Tobacco cessation: one of the most effective medical measures]

Tobacco smoking is widespread in Germany. An increase in the number of teenagers and young adults that smoke has recently been a cause for concern. The high prevalence in Germany is contrasted by inadequate preventive measures compared to international standards. Smoking behavior should always be inquired about and documented in the same way as vital signs. All smokers, regardless of the reason for contact and motivation, should receive short, low-threshold advice, e.g. using the ABC approach (ask, brief advice, cessation). In addition to repeated advice and referral to further services, the use of nicotine replacement or drug therapy is essential for the success of quitting. The combination of long- and short-acting nicotine replacement products doubles the success rate. Electronic nicotine delivery systems are not recommended for smoking cessation.

Electronic cigarettes for smoking cessation

BACKGROUND

Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol by heating an e-liquid. People who smoke, healthcare providers and regulators want to know if ECs can help people quit smoking, and if they are safe to use for this purpose. This is a review update conducted as part of a living systematic review.

OBJECTIVES

To examine the safety, tolerability and effectiveness of using electronic cigarettes (ECs) to help people who smoke tobacco achieve long-term smoking abstinence, in comparison to non-nicotine EC, other smoking cessation treatments and no treatment.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group's Specialized Register to 1 February 2023, and Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 July 2023, and reference-checked and contacted study authors.

SELECTION CRITERIA

We included trials in which people who smoke were randomized to an EC or control condition. We also included uncontrolled intervention studies in which all participants received an EC intervention as these studies have the potential to provide further information on harms and longer-term use. Studies had to report an eligible outcome.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods for screening and data extraction. Critical outcomes were abstinence from smoking after at least six months, adverse events (AEs), and serious adverse events (SAEs). We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in pairwise and network meta-analyses (NMA).

MAIN RESULTS

We included 88 completed studies (10 new to this update), representing 27,235 participants, of which 47 were randomized controlled trials (RCTs). Of the included studies, we rated ten (all but one contributing to our main comparisons) at low risk of bias overall, 58 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. There is high certainty that nicotine EC increases quit rates compared to nicotine replacement therapy (NRT) (RR 1.59, 95% CI 1.29 to 1.93; I2 = 0%; 7 studies, 2544 participants). In absolute terms, this might translate to an additional four quitters per 100 (95% CI 2 to 6 more). There is moderate-certainty evidence (limited by imprecision) that the rate of occurrence of AEs is similar between groups (RR 1.03, 95% CI 0.91 to 1.17; I2 = 0%; 5 studies, 2052 participants). SAEs were rare, and there is insufficient evidence to determine whether rates differ between groups due to very serious imprecision (RR 1.20, 95% CI 0.90 to 1.60; I2 = 32%; 6 studies, 2761 participants; low-certainty evidence). There is moderate-certainty evidence, limited by imprecision, that nicotine EC increases quit rates compared to non-nicotine EC (RR 1.46, 95% CI 1.09 to 1.96; I2 = 4%; 6 studies, 1613 participants). In absolute terms, this might lead to an additional three quitters per 100 (95% CI 1 to 7 more). There is moderate-certainty evidence of no difference in the rate of AEs between these groups (RR 1.01, 95% CI 0.91 to 1.11; I2 = 0%; 5 studies, 1840 participants). There is insufficient evidence to determine whether rates of SAEs differ between groups, due to very serious imprecision (RR 1.00, 95% CI 0.56 to 1.79; I2 = 0%; 9 studies, 1412 participants; low-certainty evidence). Due to issues with risk of bias, there is low-certainty evidence that, compared to behavioural support only/no support, quit rates may be higher for participants randomized to nicotine EC (RR 1.88, 95% CI 1.56 to 2.25; I2 = 0%; 9 studies, 5024 participants). In absolute terms, this represents an additional four quitters per 100 (95% CI 2 to 5 more). There was some evidence that (non-serious) AEs may be more common in people randomized to nicotine EC (RR 1.22, 95% CI 1.12 to 1.32; I2 = 41%, low-certainty evidence; 4 studies, 765 participants) and, again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 0.89, 95% CI 0.59 to 1.34; I2 = 23%; 10 studies, 3263 participants; very low-certainty evidence). Results from the NMA were consistent with those from pairwise meta-analyses for all critical outcomes, and there was no indication of inconsistency within the networks. Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued EC use. Very few studies reported data on other outcomes or comparisons, hence, evidence for these is limited, with CIs often encompassing both clinically significant harm and benefit.

AUTHORS' CONCLUSIONS

There is high-certainty evidence that ECs with nicotine increase quit rates compared to NRT and moderate-certainty evidence that they increase quit rates compared to ECs without nicotine. Evidence comparing nicotine EC with usual care/no treatment also suggests benefit, but is less certain due to risk of bias inherent in the study design. Confidence intervals were for the most part wide for data on AEs, SAEs and other safety markers, with no difference in AEs between nicotine and non-nicotine ECs nor between nicotine ECs and NRT. Overall incidence of SAEs was low across all study arms. We did not detect evidence of serious harm from nicotine EC, but the longest follow-up was two years and the number of studies was small. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates. Further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this review is a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.

Pharmacological and electronic cigarette interventions for smoking cessation in adults: component network meta-analyses

BACKGROUND

Tobacco smoking is the leading preventable cause of death and disease worldwide. Stopping smoking can reduce this harm and many people would like to stop. There are a number of medicines licenced to help people quit globally, and e-cigarettes are used for this purpose in many countries. Typically treatments work by reducing cravings to smoke, thus aiding initial abstinence and preventing relapse. More information on comparative effects of these treatments is needed to inform treatment decisions and policies.

OBJECTIVES

To investigate the comparative benefits, harms and tolerability of different smoking cessation pharmacotherapies and e-cigarettes, when used to help people stop smoking tobacco.

SEARCH METHODS

We identified studies from recent updates of Cochrane Reviews investigating our interventions of interest. We updated the searches for each review using the Cochrane Tobacco Addiction Group (TAG) specialised register to 29 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), cluster-RCTs and factorial RCTs, which measured smoking cessation at six months or longer, recruited adults who smoked combustible cigarettes at enrolment (excluding pregnant people) and randomised them to approved pharmacotherapies and technologies used for smoking cessation worldwide (varenicline, cytisine, nortriptyline, bupropion, nicotine replacement therapy (NRT) and e-cigarettes) versus no pharmacological intervention, placebo (control) or another approved pharmacotherapy. Studies providing co-interventions (e.g. behavioural support) were eligible if the co-intervention was provided equally to study arms.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods for screening, data extraction and risk of bias (RoB) assessment (using the RoB 1 tool). Primary outcome measures were smoking cessation at six months or longer, and the number of people reporting serious adverse events (SAEs). We also measured withdrawals due to treatment. We used Bayesian component network meta-analyses (cNMA) to examine intervention type, delivery mode, dose, duration, timing in relation to quit day and tapering of nicotine dose, using odds ratios (OR) and 95% credibility intervals (CrIs). We calculated an effect estimate for combination NRT using an additive model. We evaluated the influence of population and study characteristics, provision of behavioural support and control arm rates using meta-regression. We evaluated certainty using GRADE.

MAIN RESULTS

Of our 332 eligible RCTs, 319 (835 study arms, 157,179 participants) provided sufficient data to be included in our cNMA. Of these, we judged 51 to be at low risk of bias overall, 104 at high risk and 164 at unclear risk, and 118 reported pharmaceutical or e-cigarette/tobacco industry funding. Removing studies at high risk of bias did not change our interpretation of the results. Benefits We found high-certainty evidence that nicotine e-cigarettes (OR 2.37, 95% CrI 1.73 to 3.24; 16 RCTs, 3828 participants), varenicline (OR 2.33, 95% CrI 2.02 to 2.68; 67 RCTs, 16,430 participants) and cytisine (OR 2.21, 95% CrI 1.66 to 2.97; 7 RCTs, 3848 participants) were associated with higher quit rates than control. In absolute terms, this might lead to an additional eight (95% CrI 4 to 13), eight (95% CrI 6 to 10) and seven additional quitters per 100 (95% CrI 4 to 12), respectively. These interventions appeared to be more effective than the other interventions apart from combination NRT (patch and a fast-acting form of NRT), which had a lower point estimate (calculated additive effect) but overlapping 95% CrIs (OR 1.93, 95% CrI 1.61 to 2.34). There was also high-certainty evidence that nicotine patch alone (OR 1.37, 95% CrI 1.20 to 1.56; 105 RCTs, 37,319 participants), fast-acting NRT alone (OR 1.41, 95% CrI 1.29 to 1.55; 120 RCTs, 31,756 participants) and bupropion (OR 1.43, 95% CrI 1.26 to 1.62; 71 RCTs, 14,759 participants) were more effective than control, resulting in two (95% CrI 1 to 3), three (95% CrI 2 to 3) and three (95% CrI 2 to 4) additional quitters per 100 respectively. Nortriptyline is probably associated with higher quit rates than control (OR 1.35, 95% CrI 1.02 to 1.81; 10 RCTs, 1290 participants; moderate-certainty evidence), resulting in two (CrI 0 to 5) additional quitters per 100. Non-nicotine/placebo e-cigarettes (OR 1.16, 95% CrI 0.74 to 1.80; 8 RCTs, 1094 participants; low-certainty evidence), equating to one additional quitter (95% CrI -2 to 5), had point estimates favouring the intervention over control, but CrIs encompassed the potential for no difference and harm. There was low-certainty evidence that tapering the dose of NRT prior to stopping treatment may improve effectiveness; however, 95% CrIs also incorporated the null (OR 1.14, 95% CrI 1.00 to 1.29; 111 RCTs, 33,156 participants). This might lead to an additional one quitter per 100 (95% CrI 0 to 2). Harms There were insufficient data to include nortriptyline and non-nicotine EC in the final SAE model. Overall rates of SAEs for the remaining treatments were low (average 3%). Low-certainty evidence did not show a clear difference in the number of people reporting SAEs for nicotine e-cigarettes, varenicline, cytisine or NRT when compared to no pharmacotherapy/e-cigarettes or placebo. Bupropion may slightly increase rates of SAEs, although the CrI also incorporated no difference (moderate certainty). In absolute terms bupropion may cause one more person in 100 to experience an SAE (95% CrI 0 to 2).

AUTHORS' CONCLUSIONS

The most effective interventions were nicotine e-cigarettes, varenicline and cytisine (all high certainty), as well as combination NRT (additive effect, certainty not rated). There was also high-certainty evidence for the effectiveness of nicotine patch, fast-acting NRT and bupropion. Less certain evidence of benefit was present for nortriptyline (moderate certainty), non-nicotine e-cigarettes and tapering of nicotine dose (both low certainty). There was moderate-certainty evidence that bupropion may slightly increase the frequency of SAEs, although there was also the possibility of no increased risk. There was no clear evidence that any other tested interventions increased SAEs. Overall, SAE data were sparse with very low numbers of SAEs, and so further evidence may change our interpretation and certainty. Future studies should report SAEs to strengthen certainty in this outcome. More head-to-head comparisons of the most effective interventions are needed, as are tests of combinations of these. Future work should unify data from behavioural and pharmacological interventions to inform approaches to combined support for smoking cessation.