Heated Tobacco Products Research Articles

Mechanism of cytotoxicity induced by the cigarette smoke extract (CSE) of heated tobacco products in vascular smooth muscle cells: A comparative study of the cytotoxic effects of CSE and the ferroptosis inducer, erastin

Heated tobacco products (HTPs) are marketed worldwide as less harmful alternatives to combustible cigarettes; however, their cytotoxic mechanisms in vascular smooth muscle cells are poorly understood. Ferroptosis is defined as iron-dependent cell death caused by the accumulation of lipid peroxidation products. In this study, the cytotoxic effects of nicotine- and tar-free cigarette smoke extracts (CSE) derived from three types of HTPs and the ferroptosis inducer, erastin, on vascular smooth muscle A7r5 cells were compared. Cigarette smoke from all HTPs was generated according to the following puffing regime: 55 mL, puff volume; 30 s, puff interval; 2 s, puff duration; bell-shaped, puff profile; and no blocking of the ventilation holes. Erastin and CSE decreased mitochondrial metabolic activity and increased lactate dehydrogenase leakage. The cytotoxic effects of erastin were almost completely inhibited by the radical-trapping antioxidant, UAMC-3203; iron chelator, deferoxamine mesylate (DFO); 12/15-lipoxygenase (12/15-LOX) inhibitor, baicalein; and selective 15-LOX inhibitor, ML351. In contrast, CSE-induced cell damage was partially attenuated by UAMC-3203, baicalein, and ML351 but not by DFO. These results suggest that erastin induces ferroptosis via 15-LOX-mediated iron-dependent lipid peroxidation, whereas CSE causes iron-independent cell damage via 15-LOX-mediated lipid peroxidation-dependent and -independent mechanisms.

USERS OF TOBACCO AND NICOTINE PRODUCTS: KEY BEHAVIORAL TYPES

Aim. Establishing the type of tobacco behavior and the main motives and reasons for smoking among consumers of tobacco products.
 Material and Methods. A survey involved 817 individuals aged 18-44 in the Lviv region. Various types of tobacco products were identified among the interviewees: 96 respondents were smokers of electronic nicotine delivery systems (ENDS), 93 respondents were smokers of heated tobacco products (HTPs), and 228 respondents were smokers of classic cigarettes. A sociological survey using Horn's questionnaire was conducted to determine the types of behavior of smokers.
 Results and Discussion. The dominant type of smoking behavior, both among smokers of classic cigarettes or tobacco products for heating (HTP), and among users of nicotine through electronic cigarettes (ENDS) was the "Support" type, the second-ranked - "Playing with a cigarette", the third-ranked - "Thirst". The largest number of smokers by the behavioral type "Playing with a cigarette" was found among HTP smokers - 55.91±5.15 cases per 100 respondents. The "Thirst" type is most typical in smokers of classic cigarettes - 39.91±3.24 cases per 100 respondents. The "Support" type was the leading one for male smokers in the groups of classic cigarette smokers (47.09±3.81 cases per 100 men) and ENDS smokers (47.62±7.71 cases per 100 men), while for HTP smokers - "Playing with a cigarette" (54.55±7.51 cases per 100 men). In the group of female smokers in all studied groups, the "Support" type was the dominant type of behavior. At the same time, among female ENDS smokers, two types of behavior were dominant, namely - "Support" and "Playing with a cigarette" with an identical rate of 44.44±6.76 cases per 100 women.
 Conclusions. Determining the types of behavior of a smoker and the main reasons and motives for smoking will allow choosing a method of smoking cessation and increasing the effectiveness of quitting tobacco and nicotine use.

Why Do Physicians in Japan Use e-Cigarettes and/or Heated Tobacco Products? A Cross-Sectional Survey

Background: The tobacco industry has actively advocated for electronic cigarettes (e-cigarettes) and heated tobacco products (HTPs) as harm-reduction alternatives to traditional cigarettes. Around 40% of smoking physicians have adopted HTPs. This study aimed to uncover the motivations behind Japanese physicians’ e-cigarette and HTP use while analyzing the associations between product use, physician demographics, lifestyles, and smoking preferences. Methods: A mail-based survey was conducted in 2020, targeting 6000 male and 1500 female physicians. From the 5492 survey participants, 346 physicians aged 28 to 98 who were current smokers were selected. The survey assessed their usage of e-cigarettes and HTPs and explored the reasons for initial adoption. A multivariate logistic regression analysis examined the relationships between product use, physician characteristics, and behaviors. Results: Approximately 33.8% of smoking physicians had experimented with e-cigarettes and HTPs. E-cigarette and HTP use correlated with youthfulness, nicotine addiction, and a history of medical treatment. The primary drivers for adopting e-cigarettes and HTPs were reduced odor (74.4%), perceived harm reduction (48.7%), and decreased exposure to secondhand smoke (29.1%). Conclusions: Physicians, when transitioning from conventional cigarettes to HTPs or e-cigarettes, are primarily motivated by a desire to reduce the odor of conventional cigarettes rather than health-related concerns.

Heated tobacco smoke components delay tooth movement in a rat model

ABSTRACT Purpose This study aimed to evaluate the effect of the components of tobacco smoke from heated tobacco products (HTPs), referred to as Tobacco Smoke Components (TSCs), on tooth movement and the number of osteoclasts in rat models. Materials and Methods Wistar rats were divided into the following groups: control, distilled water-administered, cigarette TSCs-administered, and HTP TSCs-administered. Tooth movement was experimentally induced within each group using the Waldo method. Measurements were performed for tooth movement and the number of osteoclasts. Results Both cigarette and HTP TSCs decreased the number of osteoclasts and delayed the rate of tooth movement. The TSCs of cigarettes were particularly shown to have a stronger effect than the HTPs. Conclusion HTP TSCs significantly affected the rate of tooth movement; thus, orthodontists should be aware of the patient’s smoking status, as well as smoking method (paper or heated), and encourage smoking cessation during treatment.

Effect of Electronic Cigarette and Heated Tobacco Product Use on Smoking Cessation Plans among Korean Adults: The 8th Korea National Health and Nutrition Examination Survey (2019–2020)

Effect of Electronic Cigarette and Heated Tobacco Product Use on Smoking Cessation Plans among Korean Adults: The 8th Korea National Health and Nutrition Examination Survey (2019–2020)

Examining acute psychopharmacological effects of nicotine vaping versus heated tobacco products in a randomised crossover study of product naïve adult smokers

Nicotine vaping products (NVPs) and heated tobacco products (HTPs) are designed to replicate the sensory and behavioural aspects of smoking cigarettes while avoiding combustion. The success of these products as harm reduction tools will partially depend on their ability to satisfy smokers and alleviate nicotine-related withdrawal symptoms. This study aims to compare short-term effects of NVPs (Juul and Aspire PockeX) versus HTPs (IQOS) on smoking-related withdrawal relief, product satisfaction, intention to switch to NVP/HTP, perceptions and attitudes in UK adult cigarette smokers naïve to these products. In a randomized cross-over study, 45 participants visited the lab twice, at each visit trying one of the two products (NVP/HTP) and completing a questionnaire. Responses were normalized on a 0–100% scale and mean differences (MD) between NVP and HTP scores computed, with positive and negative MD values indicating greater endorsement for NVP and HTP, respectively. Cigarette cravings were reduced similarly (~ 20.0%) by both products (MD = 4.5%, 95%Confidence Interval (CI) − 4.8, 13.8). Direct positive effects (MD = − 3.5%, 95%CI − 7.2, 0.2) and adverse side effects (MD = 1.8%, 95%CI − 0.3, 3.8) were comparable after each product use, though marginally favouring HTPs. HTPs were perceived as more satisfying overall (MD = − 13.2%, 95%CI − 20.3 − 6.1) than NVPs but both were perceived as similarly addictive (MD = 3.6%, 95%CI − 4.6, 11.8), relative to cigarettes. Intention to switch to either product was comparable (MD = 4.0%, 95%CI − 5.7, 13.8). Comparison of acute use of NVP versus HTP in a sample of UK smokers naïve to these products suggests that HTPs are perceived as more satisfying than NVPs, though still less satisfying than cigarettes.Registration: The analysis plan was pre-registered, and it is available at https://osf.io/6ymdu

Effect of oxygen on the temperatures and conversion of tobacco in an electrically heated system

The goal of Heated Tobacco products (HTPs) is to devolatilize nicotine from the tobacco by a controlled electrical heating without inducing combustion and to thereby reduce the formation of harmful and potentially harmful compounds typically related to self-sustained combustion of tobacco as in conventional cigarettes. Here, we have instrumented a commercial puffing machine and an HTP with a micro-positioning system of a thin thermocouple (0.25 mm). The puffing was conducted under N2 or air. We provide the evolution of temperature as a function of time during standard puffing cycles and along the radial position within the tobacco plugs of tobacco sticks used as part of an electrically heated tobacco system (EHTS) during operation. The temperature profiles are nearly the same for the two atmospheres showing only minor influences of oxygen (maximum temperatures: 318 °C in air, 308 °C in N2, at the end of the puffing cycle). The thermal degradation of the tobacco remains always globally endothermic due to the high flow rate of the cold air flowing the tobacco during the puffing. To better understand the differences between air or N2 puffing, we have imaged the solid residues collected in the tobacco plugs by FTIR spectroscopy. The residues are clearly differentiated whatever their radial positions between air or N2 by principal component analysis of the FTIR spectra. This result highlights similar surface oxidation phenomena of the solid residue independent of the positions. Moreover, analysis of the FTIR spectra indicates that the heating of the tobacco in the EHTS is relatively uniform along the electrically-controlled heater without signs of local hot spots. These experiments were also completed by calorimetry of tobacco upon pyrolysis or oxidation, in a 3D sensor and under a fixed bed configuration (not in the EHTS). We evidence significant exothermic phenomena from about 230 °C mainly due to gas-phase oxidation of primary volatiles in the hot gas stream. During the operation of the EHTS, such potential exothermicity is counter-balanced by strong heat losses and the high flow rate of cold air flowing through the tobacco bed during the puffing. This leads to the observed net endothermic degradation of tobacco during EHTS operation.

Heated tobacco product IQOS induces unique metabolic signatures in human bronchial epithelial cells.

Metabolic signatures are lacking for heated tobacco products, making it crucial to identify new biosignatures of lung damage. This will enable the establishment of product-specific guidelines and an understanding of associated toxicity. https://bit.ly/3TkhBox.

Comparing identity, attitudes, and indicators of effectiveness in people who smoke, vape or use heated tobacco products: A cross-sectional study

BackgroundThere is limited long-term and independent research on heated tobacco products (HTPs). We compared people who used HTPs with those who used nicotine vaping products (NVP) or cigarettes on smoker identity, indicators of effectiveness and, among NVP/HTP users, perceptions of these products. MethodsAdults exclusive cigarette smokers (N = 45) and ex-smokers with medium/long-term (>3months) NVP (N = 46) or HTP use (N = 45) were recruited in London, UK. Participants completed a questionnaire assessing socio-demographics, smoking characteristics, smoker identity, dependence, intention to stop and attitudes towards HTP/NVP. ResultsIn adjusted analysis, people who used cigarettes (Mean Difference (MD) = 1.4, 95%Confidence Intervals (CI) 0.7,2.0) and HTPs (MD = 0.8, 95%CI 0.1, 1.5) reported stronger smoker identities than those who used NVPs. Compared with smokers, HTP/NVP users had lower cravings for cigarettes (MD = 3.0, 95%CI 1.6, 4.3; MD = 3.1, 95%CI 1.9, 4.3, respectively), and higher intention to stop product use (MD = −0.8, 95%CI −1.7,-0.01; MD = −1.2, 95%CI −2.0, -0.3, respectively). People using HTPs or NVPs reported similar perceived product satisfaction (HTP:M = 3.4, 95%CI 2.8, 3.9; NVP:M = 3.0, 95%CI 2.5, 3.5), efficacy for smoking cessation (HTP:M = 4.5, 95%CI 4.2, 4.9; NVP:M = 4.6, 95%CI 4.3, 4.9) and safety (HTP:M = 2.1, 95%CI 2.0, 2.2; NVP:M = 2.0, 95%CI 1.8, 2.1). HTP users reported greater perceived addictiveness than NVPs (MD = 0.3, 95%CI 0.2, 0.6). ConclusionsHTP and NVP users perceived products to be similarly acceptable and effective suggesting that HTPs, like NVPs, may support smoking cessation. However, since HTP use appears to maintain a stronger smoker identity and perceived addiction, this may suggest a more limited role of HTP for a permanent transition away from cigarettes.

Nicotine Delivery and Changes in Withdrawal and Craving During Acute Electronic Cigarette, Heated Tobacco Product, and Cigarette Use Among a Sample of Black and White People Who Smoke.

E-cigarettes and heated tobacco products (HTPs) may serve as potential options for harm reduction for smokers if they possess reward profiles similar to cigarettes. Little is known about the abuse liability of HTPs and e-cigarettes versus cigarettes in racial/ethnic minority smokers. Twenty-two nicotine-deprived people who smoke (black [n = 12] and white [n = 10]) completed three visits that included a standardized 10-puff bout followed by a 50-minute ad libitum use assessment with their usual brand cigarette (UBC), an e-cigarette, and HTP. Visits were completed in a randomized crossover design and were separated by a minimum 48-hour washout period. Assessments included plasma nicotine, Cmax, and reductions in craving and withdrawal. UBC delivered significantly greater levels of nicotine compared to the e-cigarette (p < .001) and HTP (p < .01) during both the standardized and ad libitum sessions. HTP delivered more nicotine than the e-cigarette during the standardized puffing session (p = .047) but not the ad libitum session. Only craving during the standardized puffing session and not the ad libitum session showed significant differences across products (p < .001) such that UBC resulted in the greatest reduction followed by HTP and e-cigarette. Despite greater nicotine delivery from the UBC compared to e-cigarette and HTP, participants reported reductions in craving and withdrawal across products, particularly following ad libitum use. Use of participant's UBCs (UBC) resulted in greater nicotine delivery compared to both the e-cigarette and HTP. Despite this relative difference in nicotine delivery, participants reported reductions in craving and withdrawal across products, particularly following ad libitum use. These findings suggest that in this sample of black and white people who smoke, HTPs and e-cigarettes provided significant relief from negative symptoms that maintain smoking.

Study on tobacco quality improvement and bacterial community succession during microbial co-fermentation

The high levels of starch, cellulose and protein in tobacco can produce a strong irritating smoke and diminish its flavor and overall quality, but the tobacco quality can be improved by microorganisms abundant in tobacco during fermentation. In this study, we screened and identified three strains from tobacco with high amylase, cellulase, and protease activities. The co-fermentation of Bacillus velezensis A2 and Bacillus endophyticus A4 could effectively reduce the content of starch, cellulose and protein in tobacco, leading to an increase in the content of reducing sugar and alterations in the surface of fermented tobacco, making it looser, more wrinkled, and porous, coupled with the potential to mitigate the presence of the harmful substance nicotine. Additionally, compared with the control, A2 +A4 co-fermentation increased the content of aroma components by 108.33%, and remarkably improved the sensory quality of Heat-not-Burn (HnB) cigarettes. Moreover, Bacillus, Pseudomonas and Klebsiella were genera with high abundance before and after A2 +A4 co-fermentation, but Bacillus gradually became the dominant genus, with its relative abundance increased from 0.49% to 32.65%. LEfSe analysis identified Bacillus as a crucial biomarker in tobacco after microbial co-fermentation. PICRUSt analysis showed that microbial co-fermentation could promote the metabolic pathways associated with substrate utilization. This study provided new strains and a theoretical basis for optimizing the fermentation process to improve the quality of tobacco for HnB cigarettes.

Key Challenges for In Vitro Testing of Tobacco Products for Regulatory Applications: Recommendations for the In Vitro Mouse Lymphoma Assay.

The Institute for In Vitro Sciences (IIVS) is sponsoring a series of workshops to develop recommendations for optimal scientific and technical approaches for conducting in vitro assays to assess potential toxicity within and across traditional tobacco and various tobacco and nicotine next-generation products (NGPs), including Heated Tobacco Products (HTPs) and Electronic Nicotine Delivery Systems (ENDS). This report was developed by a working group composed of attendees of the seventh IIVS workshop, 'Approaches and recommendations for conducting the mouse lymphoma gene mutation assay (MLA) and introduction to in vitro disease models', which was held virtually on 21-23 June 2022. This publication provides a background overview of the MLA, and includes the description of assay conduct and data interpretation, key challenges and recommended best practices for evaluating tobacco and nicotine products, with a focus on the evaluation of NGPs, and a summary of how the assay has been used to evaluate and compare tobacco and nicotine products.

A Pumping Method for Assessing Airtightness of Packs - Application to Heated Tobacco Products *

SUMMARY The airtightness of heated tobacco product (HTP) packs is a very important indicator for the product quality and is also of great importance during the conditioning process. A method for evaluation of the airtightness was developed based on the air pressure difference in a constant pumping configuration. The essential feature of this method is that the pressure difference between the inside and the outside of the HTP packs during the deflation process is used to characterize the sealing quality of HTP packs. The detailed setup, the principle as well as the determination procedure are described. The accuracy and the repeatability of the method were assessed, and the effect of airtightness on the conditioning process was also investigated. The developed method is proven to be reliable with a standard deviation less than 0.09 kPa and repeatability less than 0.30 kPa. In addition, it was found that, although the transmission of moisture between HTPs and atmosphere could not be entirely prevented by the packs, airtightness still plays a significant role during the conditioning process, especially if the airtightness was at a relatively low level (e.g., lower than 1.5 kPa under a pumping flow rate of 200 mL/min). The method provides a promising way to assess and monitor the sealing quality of HTP packs, and it is suggested that the airtightness of the pack should not be lower than 2 kPa under a pumping flow rate of 200 mL/min. [Contrib. Tob. Nicotine Res. 32 (2023) 140–145]

Impact of More Intense Smoking Parameters and Flavor Variety on Toxicant Levels in Emissions of a Heated Tobacco Product.

IQOS HEETS are promoted as reduced-risk alternatives to cigarettes. Although some studies have investigated the chemical composition of HEETS emissions, little is known on whether toxicant levels in such emissions are affected by different puffing parameters and flavor varieties. This has important implications when assessing actual human exposure, since IQOS users develop a specific and personalized puffing behavior and may use different HEETS variants. This study measured the levels of nicotine, total particulate matter, carbonyl compounds, and tobacco-specific nitrosamines (TSNAs) in the emissions of nine differently flavored HEETS and two cigarettes (1R6F and Marlboro Red, MR). Emissions from Yellow HEETS, 1R6F, and MR were collected using the World Health Organization Intense smoking regime and four more intense smoking regimes. Yellow HEETS aerosol contained lower levels of toxicants compared to 1R6F and MR smoke. More intense smoking regimes increased carbonyl release in cigarette smoke, whereas only higher puff frequency led to lower levels of toxicants in Yellow HEETS aerosol. Some HEETS varieties exhibited higher levels of formaldehyde and TSNAs in their aerosols compared to Yellow HEETS. Puff frequency was identified as the only smoking parameter that significantly lowered the release of almost all toxicants in Yellow HEETS, whereas a combination of higher puff volume and puff duration led to increased levels of some carbonyls. Differences in toxicant levels between various commercially available HEETS have important implications when assessing their health impact, as their consumption might induce different toxicant exposure and health effects. HEETS release about half as much nicotine and substantially lower levels of toxicants compared to cigarettes. Literature data showed that puffing intensity is increased in cigarette smokers switching to HEETS, maybe in reaction to these lower nicotine levels. Our results show a differential impact of increased puff frequency, puff duration, and puff volume in the release of toxicants from HEETS. Thus, industry-independent studies on puff topography are critical to make choices for the most relevant puffing regime for heated tobacco product regulation. Regulators should consider evaluating the health impact of multiple HEETS varieties, as the tobacco filler composition significantly affects the release of certain toxicants.

Impairment of Endothelial Function by Aerosol From Marijuana Leaf Vaporizers.

Marijuana leaf vaporizers, which heat plant material and sublimate Δ-9-tetrahydrocannabinol without combustion, are popular alternatives to smoking cannabis that are generally perceived to be less harmful. We have shown that smoke from tobacco and marijuana, as well as aerosol from e-cigarettes and heated tobacco products, impair vascular endothelial function in rats measured as arterial flow-mediated dilation (FMD). We exposed 8 rats per group to aerosol generated by 2 vaporizer systems (Volcano and handheld Yocan) using marijuana with varying Δ-9-tetrahydrocannabinol levels, in a single pulsatile exposure session of 2 s/min over 5 minutes, and measured changes in FMD. To model secondhand exposure, we exposed rats for 1 minute to diluted aerosol approximating release of uninhaled Volcano aerosol into typical residential rooms. Exposure to aerosol from marijuana with and without cannabinoids impaired FMD by ≈50%. FMD was similarly impaired by aerosols from Yocan (237 °C), and from Volcano at both its standard temperature (185 °C) and the minimum sublimation temperature of Δ-9-tetrahydrocannabinol (157 °C), although the low-temperature aerosol condition did not effectively deliver Δ-9-tetrahydrocannabinol to the circulation. Modeled secondhand exposure based on diluted Volcano aerosol also impaired FMD. FMD was not affected in rats exposed to clean air or water vapor passed through the Volcano system. Acute direct exposure and modeled secondhand exposure to marijuana leaf vaporizer aerosol, regardless of cannabinoid concentration or aerosol generation temperature, impair endothelial function in rats comparably to marijuana smoke. Our findings indicate that use of leaf vaporizers is unlikely to reduce the vascular risk burden of smoking marijuana.

A multicenter prospective randomized controlled trial investigating the effects of combustion-free nicotine alternatives on cardiovascular risk factors and metabolic parameters in individuals with type 2 diabetes who smoke: the DiaSmokeFree study protocol

Stopping smoking is crucial for public health and especially for individuals with diabetes. Combustion-free nicotine alternatives like e-cigarettes and heated tobacco products are increasingly being used as substitutes for conventional cigarettes, contributing to the decline in smoking prevalence. However, there is limited information about the long-term health impact of those products in patients with diabetes. This randomized controlled trial aims to investigate whether switching from conventional cigarettes to combustion-free nicotine alternatives will lead to a measurable improvement in cardiovascular risk factors and metabolic parameters over a period of 2 years in smokers with type 2 diabetes. The multicenter study will be conducted in seven sites across four countries. A total of 576 smokers with type 2 diabetes will be randomly assigned (1:2 ratio) to either standard of care with brief cessation advice (Control Arm) or combustion-free nicotine alternatives use (Intervention Arm). The primary end point is the change in the proportion of patients with metabolic syndrome between baseline and the 2-year follow-up. Additionally, the study will analyze the absolute change in the sum of the individual factors of metabolic syndrome at each study time point. Patient recruitment has started in September 2021 and enrollment is expected to be completed by December 2023. Results will be reported in 2026. This study may provide valuable insights into cardiovascular and metabolic health benefits or risks associated with using combustion-free nicotine alternatives for individuals with type 2 diabetes who are seeking alternatives to tobacco cigarette smoking. The study protocol, informed consent forms, and relevant documents were approved by seven ethical review boards. Study results will be disseminated through articles published in high-quality, peer-reviewed journals and presentations at conferences.

Aerosol Emissions from Heated Tobacco Products: A Review Focusing on Carbonyls, Analytical Methods, and Experimental Quality.

We provide an extensive review of 17 independent and industry-funded studies targeting carbonyls in aerosol emissions of Heated Tobacco Products (HTPs), focusing on quality criteria based on the reproducibility of experiments, appropriate analytic methods, and puffing regimes. Most revised studies complied with these requirements, but some were unreproducible, while others failed to consider analytical variables that may have affected the results and/or produced unrealistic comparisons. We also provide a review of the literature on the physicochemical properties of heated tobacco and HTP aerosols, as well as the evaluation of HTPs by regulatory agencies, addressing various critiques of their relative safety profile. The outcomes from the revised studies and regulatory evaluations tend to agree with and converge to a general consensus that HTP aerosols expose users to significantly lower levels of toxicity than tobacco smoke.

Health warning labels on heated tobacco products and their impact on use intentions and risk perceptions: a cross-sectional study of adult tobacco users in the US and Israel.

Health warning labels (HWLs) represent an evidence-based tobacco control strategy; however, their application to heated tobacco products (HTPs) and related impacts are understudied. This study examined the impact of HTP HWLs on HTP use intentions and risk perceptions among current tobacco users. We analyzed cross-sectional survey data from adults in the US and Israel reporting past-month tobacco use and awareness of HTPs (N = 424). Multivariate analyses examined: (1) sociodemographics in relation to self-reported impact of HTP HWLs (i.e., more concerned about HTP use, reassured, no effect [referent]) among those who noticed HTP HWLs (multinomial regressions); and (2) HWL impacts in relation to HTP use intentions and perceived addictiveness and harm (linear regressions). Among participants who noticed HTP HWLs (n = 372, 87.7%), 27.7% reported HWLs increased their concerns about HTP use, 22.6% were reassured about use, and 49.7% reported no effect. Factors associated with increased concern (vs. no effect) included other tobacco product use (aOR = 2.10, 95% CI 1.21-3.64) and being female (aOR = 1.77, 95% CI 1.03-3.05). Factors associated with being reassured about HTPs use (vs. no effect) included current HTP use (aOR = 2.11, 95% CI 1.11-4.00) and being from Israel (vs. US: aOR = 3.85, 95% CI 1.85-7.69), female (aOR = 1.91, 95% CI 1.07-3.42), and less educated (< college education: aOR = 2.57, 95% CI 1.42-4.63). Reporting that HWLs on HTPs increased concern (β = 0.46, 95% CI 0.03-0.89) and reassured of use (β = 0.94, 95% CI 0.47-1.41) were positively associated with HTP use intentions; no associations with risk perceptions were found. Findings indicate that most tobacco users noticed HWLs on HTPs, but the majority reported no effect or being reassured of using HTPs, effects that were magnified for specific subgroups. Both increased concern and reassurance correlated with greater use intentions. Additional research should evaluate HTP HWL impacts and ensure effectiveness in communicating risks and discouraging use.

Comparison of Publications on Heated Tobacco Products With Conventional Cigarettes and Implied Desirability of the Products According to Tobacco Industry Affiliation: A Systematic Review.

Heated tobacco products (HTPs) have been advertised as "reduced-harm" tobacco products compared to conventional cigarettes (CC); however, no direct evidence supporting HTPs being desirable for human health exists. A previous systematic review reported that evidence on HTPs published in 2017 or earlier was primarily drawn from industry-related papers. We aimed to investigate whether tobacco industry-affiliated studies are more likely to conclude that HTPs are more desirable than CC. PubMed and Ichushi-Web were searched up to March 15, 2022, for studies on HTPs published in 2017 or after. We selected studies that assessed any measures of HTPs and CC, including secondary analyses using gray literature in English or Japanese. We excluded review articles except for a meta-analysis that met the aforementioned criteria. Data on the authors' affiliations, grant, conflict of interest, category of research subjects, and interpretation were extracted. Research members in two groups independently assessed the papers; discrepancies were solved by discussion between the groups. Overall, 134 studies met the criteria. Eighty-seven (64.9%) of them were affiliated with the tobacco industry. Of the 134 studies, 56.3% (49/87) of the industry-affiliated studies versus 19.1% (9/47) of nonindustry-affiliated studies concluded that HTPs were more desirable than CC (p < .01). No study investigated clinically relevant outcomes, such as disease occurrence. Publications on HTPs in the biomedical literature from January 2017 to March 2022 were dominated by tobacco industry-affiliated studies. More than half of them concluded that HTPs were more desirable than CC compared to independent studies. Tobacco industry advertises HTPs as "reduced-harm" tobacco products compared to CC. HTP users tend to consider HTPs as alternative tobacco products less harmful than CC (ie, products for "harm reduction"). Our results demonstrated that papers written by tobacco industry-affiliated authors concluded that HTPs were more desirable than CC compared to papers by independent authors. However, all their judgments were based on surrogate outcomes. Surrogate outcomes are not necessarily linked to clinically relevant outcomes such as disease occurrence. Further studies on HTPs using clinically relevant outcomes are warranted by independent authors from tobacco industry.

Relationship between heated tobacco product use and allergic rhinitis in Korean adults.

Combustible cigarette (CC) smoking is a risk factor for chronic obstructive pulmonary disease (COPD) and asthma, and some studies reported that tobacco smoking might affect the development or symptom control of allergic rhinitis, sinusitis, and atopic dermatitis. However, evidence on the health risks of heated tobacco products (HTPs) is lacking. We investigated the prevalence of respiratory and allergic diseases according to tobacco use types in Korean adults. We used data from 18230 adults in the Korea National Health and Nutrition Examination Survey. Multiple logistic regression analyses were performed to assess the prevalence of respiratory and allergic diseases according to tobacco use types (current exclusive CC use, current exclusive HTPs use, and dual use of CC and HTPs). The prevalence of exclusive CC users, exclusive HTPs users, dual users of CC and HTPs was 15% (n=2740), 1% (n=182), and 2.4% (n=435), respectively. The prevalence of COPD was higher among past tobacco users (AOR=2.37; 95% CI: 1.02-5.51) versus no tobacco use group. The prevalence of asthma was higher among past tobacco users or exclusive CC users (AOR=1.73; 95% CI: 1.26-2.38, and AOR=1.57; 95% CI: 1.08-2.26) versus non-users of tobacco. The prevalence of allergic rhinitis was higher among past tobacco users versus non-users of tobacco (AOR=1.33; 95% CI: 1.13-1.57), and the prevalence of allergic rhinitis was higher among exclusive HTPs users versus non-users of tobacco or exclusive CC users (AOR=1.60; 95% CI: 1.06-2.42, and AOR=1.74; 95% CI: 1.14-2.66). The adjusted odds of sinusitis and atopic dermatitis were not significantly different between tobacco use types. Exclusive use of HTPs was associated with allergic rhinitis in Korean adults. Further longitudinal studies are needed to clarify the health risk of HTPs.