Objective To review and synthesise the global evidence regarding the health effects of electronic cigarettes (e‐cigarettes, vapes). Study design Umbrella review (based on major independent reviews, including the 2018 United States National Academies of Sciences, Engineering, and Medicine [NASEM] report) and top‐up systematic review of published, peer‐reviewed studies in humans examining the relationship of e‐cigarette use to health outcomes published since the NASEM report. Data sources Umbrella review: eight major independent reviews published 2017–2021. Systematic review: PubMed, MEDLINE, Scopus, Web of Science, the Cochrane Library, and PsycINFO (articles published July 2017 – July 2020 and not included in NASEM review). Data synthesis Four hundred eligible publications were included in our synthesis: 112 from the NASEM review, 189 from our top‐up review search, and 99 further publications cited by other reviews. There is conclusive evidence linking e‐cigarette use with poisoning, immediate inhalation toxicity (including seizures), and e‐cigarette or vaping product use‐associated lung injury (EVALI; largely but not exclusively for e‐liquids containing tetrahydrocannabinol and vitamin E acetate), as well as for malfunctioning devices causing injuries and burns. Environmental effects include waste, fires, and generation of indoor airborne particulate matter (substantial to conclusive evidence). There is substantial evidence that nicotine e‐cigarettes can cause dependence or addiction in non‐smokers, and strong evidence that young non‐smokers who use e‐cigarettes are more likely than non‐users to initiate smoking and to become regular smokers. There is limited evidence that freebase nicotine e‐cigarettes used with clinical support are efficacious aids for smoking cessation. Evidence regarding effects on other clinical outcomes, including cardiovascular disease, cancer, development, and mental and reproductive health, is insufficient or unavailable. Conclusion E‐cigarettes can be harmful to health, particularly for non‐smokers and children, adolescents, and young adults. Their effects on many important health outcomes are uncertain. E‐cigarettes may be beneficial for smokers who use them to completely and promptly quit smoking, but they are not currently approved smoking cessation aids. Better quality evidence is needed regarding the health impact of e‐cigarette use, their safety and efficacy for smoking cessation, and effective regulation. Registration Systematic review: PROSPERO, CRD42020200673 (prospective).

ObjectivesCardiovascular disease (CVD) is highly preventable and optimal treatments based on absolute risk can halve risk of future events. Compared with women, men have higher risks of developing CVD. However, women can experience suboptimal treatment. We aimed to quantify sex differences in CVD risk, assessment and treatment in Australian adults.Design, participants, settingCross-sectional analysis of nationally representative data from interview, physical measures, medication review and blood and urine samples, from 2011 to 2012 Australian Health Survey participants aged 45–74 (n=11 518).Outcome measuresCVD risk factors, absolute 5-year risk of a primary CVD event, blood pressure and cholesterol assessment in the previous 2 and 5 years and use of recommended CVD preventive medications were compared using Poisson regression to estimate age-adjusted male versus female prevalence ratios (PRs).ResultsWomen had a generally more favourable CVD risk factor profile than men, including lower: current smoking prevalence (women=14.5%; men=18.4%, PR=0.78, 95% CI=0.70 to 0.88); body mass index (women (mean)=28.3 kg/m2; men (mean)=28.8 kg/m2, p<0.01); systolic and diastolic blood pressure (systolic: women (mean)=127.1 mm Hg; men (mean)=130.5 mm Hg, p<0.001); blood glucose (women (mean)=5.2 mmol/L; men (mean)=5.5 mmol/L); diabetes prevalence (women=6.8%; men=12.5%, PR=0.55, 95% CI=0.44 to 0.67); prior CVD (women=7.9%; men=11.3%) and absolute primary CVD risk (absolute 5-year CVD risk >15%: women=6.6%, 95% CI=5.4 to 7.8; men=15.4%, 95% CI=13.9% to 16.9%). Compared with men, women had higher low-density lipoprotein, high-density lipoprotein and total cholesterol and sedentary behaviour and lower physical activity. Blood pressure and cholesterol assessment were common in both sexes. Among those at high absolute risk, age-adjusted proportions receiving recommended CVD medications were low, without sex differences (women=21.3%; men=23.8%, PR=0.93, 95% CI=0.49 to 1.78). Fewer women than men with prior atherosclerotic CVD were receiving recommended treatment (women=21.8%, men=41.4%, PR=0.55, 95% CI=0.31 to 0.96).ConclusionWomen have a more favourable CVD risk factor profile than men. Preventive treatment is uncommon and women with prior atherosclerotic CVD are around half as likely as men to be receiving recommended treatment.

Introduction The “hardening hypothesis” proposes that as the prevalence of smoking in a population declines, there will be a “hardening” of the remaining smoker population. This review examines the evidence regarding smokers’ motivation, dependence and quitting behaviour as smoking prevalence declines, to assess whether population “hardening” (decreasing propensity to quit) or “softening” (the converse) is occurring. Methods MEDLINE, PsychINFO, Scopus, Web of Science and Cochrane Library were searched to July 2019, using terms related to smoking and hardening, for reviews and large, population-based repeat cross-sectional studies. There were additional searches of reference lists and citations of key research articles. Two reviewers screened half the titles and abstracts each, and two reviewers screened full texts independently using tested criteria. Four reviewers independently and systematically extracted data from eligible publications, with one reviewer per study, checked by another reviewer. Results Of 265 titles identified, three reviews and ten repeat cross-sectional studies were included. Reviews concluded that hardening has not occurred among the general smoking population over time. Among repeated cross-sectional studies, five examined motivation, nine examined dependence, five examined hardcore smoking, and two examined quit outcomes. All but one study found a lack of hardening. Most found softening within the smoking population, consistent across hardening indicators, definitions, countries (and tobacco control environments) and time periods examined. Conclusions Tobacco control reduces smoking prevalence and fosters a smoking population more amenable to evidence-based interventions. Based on the weight of the available evidence, the “hardening hypothesis” should be rejected and the reality of softening accepted. Implications This umbrella review and systematic review provides a critical consideration of evidence from psychology and other fields regarding the “hardening hypothesis” – a persistent myth undermining tobacco control. It reaches the conclusion that the sum-total of the world-wide evidence indicates either “softening” of the smoking population, or a lack of hardening. Hence, tobacco control reduces smoking prevalence and fosters a smoking population more amenable to evidence-based interventions. The review indicates that the time has come to take active steps to combat the myth of hardening and to replace it with the reality of “softening”.

Highlights Use of preventive medications following a major CVD event was sub-optimal. Use of preventive medications was lower in women vs men at 3 months after CVD event. Relationship persisted over time with similar findings at 12 months after CVD event.

BackgroundElectronic cigarettes (e-cigarettes) are relatively new products with substantial public health impacts. Evidence on their effects is diverse and emerging rapidly, presenting challenges to high-quality policymaking and decision-making. This paper addresses these challenges by developing and presenting a framework for the public health assessment of e-cigarettes, using the Australian context as an example.MethodsFramework development involved stakeholder engagement, development of guiding principles, and consideration of existing relevant frameworks and the evidence requirements of current policy options, identified in published and grey literature.ResultsGuiding principles include the need for the framework to: be evidence based; include consideration of the likely balance of benefits and risks of e-cigarettes, uncertainty and safety; support equity; support the ongoing application of evidence to high-quality policy and practice; and consider potential competing interests. The framework draws upon: health technology assessment; health impact assessment; environmental health risk assessment; healthcare recommendations evidence evaluation; consumer goods regulation; medicine and chemical scheduling; tobacco product evaluation; previous reviews and the precautionary principle. Final framework components are: (1) characterisation of products under consideration; (2) definition of populations of interest; (3) characterisation of tobacco smoking, control and impacts on health and well-being; (4) review of evidence on patterns of e-cigarette use; (5) review of evidence on e-cigarette use and health outcomes; (6) assessment of likely risks, benefits and safety; (7) identification and assessment of policy options to optimise health outcomes.ConclusionsStructured and ongoing public health assessment of e-cigarette use is likely to support health through enhancing evidence-based decision-making.