Heated tobacco products (HTPs), such as IQOS, glo, and Ploom TECH, with a variety of flavored tobacco-containing inserts, have reportedly achieved a significant market share in Japan. We analyzed data from Wave 1 of the ITC Japan Survey, a nationally representative web survey conducted in February to March 2018 among 4684 adult participants to estimate the prevalence of HTP use, describe characteristics of HTP users, and explore user preferences for HTP device and flavor. The overall prevalence of monthly HTP use was 2.7% (1.7% daily use). Virtually all HTP users were current cigarette smokers (67.8%) or former smokers (25.0%); only 1.0% of HTP users were never smokers. Among HTP users, IQOS was the most frequently reported brand used (64.5%), and menthol was the most common flavor reported (41.5%). IQOS was used more by younger respondents and those who reported daily use, while Ploom TECH was more popular among older respondents and non-daily HTP users. This is one of the first non-industry funded studies to explore the use of HTPs in Japan.

Background: Electronic cigarettes (e-cigarettes) are widely promoted as harm-reduction products for smokers, and smokers commonly perceive them as less harmful than combustible cigarettes. One of the key questions regarding public health consequences of e-cigarettes is the magnitude of harm reduction achievable by smokers who switch from combustible cigarettes to e-cigarettes. We conducted a systematic literature review of epidemiological studies that estimated odds of respiratory and cardiovascular outcomes among former smokers who use e-cigarettes compared to current smokers. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. We searched the PubMed and Embase databases in September 2020 to identify epidemiological studies that compared odds of cardiovascular and respiratory outcomes among former smokers who transitioned to e-cigarettes relative to odds among current smokers not using e-cigarettes (current exclusive smokers). We included studies that provided direct estimates of relevant odds ratios (ORs). We also included studies where indirect estimates of relevant ORs could be calculated based on published results. Two reviewers independently extracted data and conducted quality appraisals. Results: Six population-based studies with sample sizes ranging from 19,475 to 161,529 respondents met review inclusion criteria, five of which were cross-sectional and one longitudinal. Three studies reported respiratory outcomes and three reported cardiovascular outcomes. ORs of respiratory outcomes (including chronic obstructive pulmonary disease, chronic bronchitis, emphysema, asthma, and wheezing) in former smokers who transitioned to e-cigarettes versus current exclusive smokers were below 1.0, ranging from 0.58 (95%CI 0.36–0.94) to 0.66 (95%CI 0.50–0.87; all p < 0.05). All ORs for cardiovascular outcomes (including stroke, myocardial infarction, and coronary heart disease) did not differ significantly from 1.0. Conclusion: Though our review included a small number of studies, it provided consistent results. Former smokers who transitioned to e-cigarettes showed ~ 40% lower odds of respiratory outcomes compared to current exclusive smokers. Switching from smoking to e-cigarette does not appear to significantly lower odds of cardiovascular outcomes. Since the utility of cross-sectional studies for causal inference remains limited, both randomized controlled trials and prospective cohort studies are needed to better evaluate contributions of e-cigarettes as harm reduction tools for smokers.

Use of heated tobacco products (HTPs) among current smokers is becoming increasingly popular in Japan. This study aims to compare characteristics and tobacco-related behaviors among concurrent users of HTPs and combustible cigarettes (n = 644) with exclusive smokers (n = 3194) or exclusive HTP users (n = 164). The secondary aim was to explore heterogeneity within concurrent use subgroups. Data were from Wave 1 of the ITC Japan Survey, a nationally representative web survey conducted from February to March 2018. Concurrent cigarette-HTP users were younger and wealthier than exclusive smokers. However, there were no difference in the frequency of smoking, number of cigarettes per day, and smoking cessation behaviors between the two groups, suggesting that HTPs reinforce nicotine dependence. Compared to exclusive HTP users, concurrent cigarette-HTP users reported higher frequency of non-daily HTP use, and lower number of tobacco-containing inserts per day. Almost all concurrent cigarette-HTP users smoked every day (93.9%); 48.4% both smoked and used HTPs daily (dual daily users, n = 396), while 45.5% were daily smokers and non-daily HTP users (predominant smokers, n = 213). Concurrent user subgroups differed from each other on age, tobacco use behaviors, and quit intention. Alongside heterogeneity between concurrent and exclusive product users, differences across concurrent use subgroups highlight the importance of considering frequency of use in characterizing poly-tobacco users.

Following their introduction a decade ago, electronic cigarettes (e-cigarettes) have grown in popularity. Given their novelty, knowledge of the health consequences of e-cigarette use remains limited. Epidemiologic studies have not comprehensively explored associations between e-cigarette use and hypertension, a highly prevalent health condition and major contributor to cardiovascular disease burden. In this study, cross-sectional associations of cigarette smoking and e-cigarette use (vaping) with self-reported diagnosed hypertension were evaluated among 19,147 18–55 year old respondents in Wave 3 (2015–2016) of the Population Assessment of Tobacco and Health Study. Multivariable analyses first modeled smoking and vaping as separate 2-category variables, then as a 6-category composite variable accounting for former smoking. After adjusting for potential confounders, current vaping (aOR = 1.31; 95%CI: 1.05–1.63) and current smoking (aOR = 1.27; 95%CI: 1.10–1.47) were both associated with higher odds of hypertension. In analyses modeling smoking and vaping compositely, respondents who were concurrently smoking and vaping had the highest odds of hypertension (aOR = 1.77; 95%CI: 1.32–2.39 [referent: never smokers]). These results differ somewhat from prior epidemiologic studies of vaping and respiratory outcomes, which consistently report smaller point estimates for current vaping than for current smoking. Our findings reinforce the uncertainty surrounding long-term health consequences of vaping, as well as highlight important distinctions between respiratory and cardiovascular outcomes when considering the harm reduction potential of e-cigarettes.

Background: Dual use of tobacco cigarettes and e-cigarettes (“dual use”) is the most common poly-tobacco use pattern among U.S. adults. Whether dual use facilitates or inhibits smoking cessation is of concern, yet limited information exists regarding continuation of dual use over time. Purpose: This study examined variation in nicotine product use over a one-year period, and evaluated predictors of smoking abstinence among dual users. Methods: Data from 1,082 dual users of tobacco cigarettes and e-cigarettes were analyzed using Wave 1 (2013–2014) and Wave 2 (2014–2015) of the Population Assessment of Tobacco and Health Study. Descriptive analyses assessed variation in nicotine product use at Wave 2. Weighted logistic regression was used to identify correlates of smoking abstinence. Results: The majority of Wave 1 dual users (88.5%) continued using combustible tobacco at Wave 2: 59.2% were exclusive cigarette smokers, 25.5% remained dual users, and 3.8% reported some other combustible tobacco use pattern. The odds of being smoke-free at Wave 2 were higher among dual users who reported everyday (versus someday) e-cigarette use (aOR: 1.85; 95% CI: 1.18–2.89). Everyday use of tobacco cigarettes was inversely associated with smoking abstinence (aOR 0.33; 95% CI: 0.21–0.51). Conclusions: Over a one year period, most dual users still smoked tobacco cigarettes. Frequency of cigarette and e-cigarette use at Wave 1 were each associated with odds of smoking abstinence. Findings suggest that daily e-cigarette use may increase dual users’ chances of becoming smoke free.

Heated tobacco products (HTP) have diversified global tobacco markets, and user characteristics remain understudied. This study evaluated sociodemographic characteristics, nicotine-related perceptions, and behaviors of current HTP users within a sample of adult (18+ years) nicotine users across four countries. Data were from current smokers or nicotine vaping product (NVP; known as “e-cigarettes”) users from Canada, England, the United States, and Australia (n = 11 421) who participated in the 2018 ITC Four Country Smoking and Vaping Survey. Current (at-least-monthly) HTP users were characterized (n = 441), and weighted multivariable logistic regressions examined correlates of HTP use. Compared to nonusers, current HTP users were younger (mean age: 44.4 vs 31.0 years; p < .001) and had higher socioeconomic status (p < .001). A majority of current HTP users used HTPs nondaily (daily: 40.3% vs nondaily: 59.7%). Most HTP users concurrently used both cigarettes and NVPs (90.5%). Among concurrent cigarette-HTP-NVP users, 36.2% used all three products daily. Use of other combusted tobacco products (cigars, cigarillos, pipe, waterpipe/hookah), cannabis, and binge drinking were each associated with current HTP use. HTP use was more common among smokers intending to quit within 6 months or reporting a quit attempt in the past 18 months, and vapers who had experienced negative side effects. HTP users in this sample tended to be younger and more affluent. Most reported concurrent use of multiple nicotine products and other substances. Those cigarette smokers who used HTPs appeared more interested in smoking cessation, while some characteristics of concurrent HTP-NVP users were suggestive of dissatisfaction with NVPs. Few studies have scrutinized characteristics of HTP early adopters in emerging markets. Our results indicate that in 2018, characteristics of established nicotine users who adopted HTP use in four high-income Western countries mirror those of HTP users in East Asian markets (South Korea and Japan) where HTPs are popular. HTP users reported high levels of concurrent use of noncigarette-combusted tobacco products (e.g., cigars, pipe tobacco). These findings point to the need for future longitudinal studies of HTP use given the implications of those use patterns on the harm reduction potential of HTPs. HTP user characteristics may yield important information to consider in regulation of these products.