Critical appraisal of interventional clinical trials assessing heated tobacco products: a systematic review

Seeking to be seen as legitimate members of the scientific community? An analysis of British American Tobacco and Philip Morris International's involvement in scientific events

INTRODUCTION

For decades, tobacco companies manipulated and misused science. They funded and disseminated favourable research and suppressed research that showed the harms of their products, deliberately generating misinformation. While previous work has examined many of the practices involved, their engagement in scientific events has so far not been systematically studied. Here, we examine the involvement of British American Tobacco (BAT) and Philip Morris International (PMI) in scientific events, including conferences, symposia and workshops.

METHODS

Our analysis involved two steps. First, we collected all available data PMI and BAT provided on their websites to identify events. Second, we extracted information about the nature of tobacco industry involvement from event websites and materials.

RESULTS

We identified 213 scientific events that BAT and/or PMI representatives attended between April 2012 and September 2021. Most events took place in high-income countries in Europe and North America. They covered a diverse range of fields, including toxicology (n=60, 28.1%), medicine (n=25, 11.7%), biology (n=24, 11.3%), chemistry (n=23, 10.8%) and aerosol science (n=18, 8.5%), as well as dentistry (n=9, 4.2%), pharmaceutical science (n=8, 3.8%) and computing (n=8, 3.8%). We identified 356 posters provided by BAT and PMI that linked to 118 events (55.4%) as well as 77 presentations from 65 events (30.5%). Industry involvement through sponsorship (nine events), exhibition (three events) or organising committee (one event) was rare.

CONCLUSION

BAT and PMI representatives attended a large number and wide range of scientific events. Given that scientific events could be a crucial platform for building connections in the scientific sphere and disseminating industry's messages, this work highlights the importance of denormalising the tobacco industry's involvement in scientific events.

Intermittent nicotine access is as effective as continuous access in promoting nicotine seeking and taking in rats

RATIONALE

Nicotine is a principal psychoactive agent in tobacco, contributing to tobacco's addictive potential. Preclinical studies on the effects of voluntary nicotine intake typically use self-administration procedures that provide continuous nicotine access during each self-administration session. However, many smokers consume cigarettes intermittently rather than continuously throughout each day. For drugs including cocaine and opioids, research in laboratory rats shows that intermittent intake can be more effective than continuous intake in producing patterns of drug use relevant to addiction.

OBJECTIVE

We determined how intermittent versus continuous nicotine self-administration influences nicotine seeking and taking behaviours.

METHODS

Female and male rats had continuous (i.e., Long Access; LgA, 6 h/day) or intermittent (IntA; 12 min ON, 60 min OFF, for 6 h/day) access to intravenous nicotine (15 µg/kg/infusion), for 12 daily sessions. We then assessed intake, responding for nicotine under a progressive ratio schedule of drug reinforcement and cue- and nicotine-induced reinstatement of drug seeking. We also estimated nicotine pharmacokinetic parameters during LgA and IntA self-administration.

RESULTS

Overall, LgA rats took twice more nicotine than did IntA rats, yielding more sustained increases in estimated brain concentrations of the drug. However, the two groups showed similar motivation to seek and take nicotine, as measured using reinstatement and progressive ratio procedures, respectively.

CONCLUSIONS

Intermittent nicotine use is just as effective as continuous use in producing addiction-relevant behaviours, despite significantly less nicotine exposure. This has implications for modeling nicotine self-administration patterns in human smokers and resulting effects on brain and behaviour.

Impact of exposures to Heated Tobacco Products in the media and through social connections on product perceptions and use

INTRODUCTION

Little is known about media exposures to heated tobacco products (HTPs). In this study, we examined sources of HTP exposure, including from paid and unpaid media and social connections, in relation to HTP use and use intentions.

METHODS

In the fall of 2021, we conducted a cross-sectional survey among adult online panelists (aged 18-45 years) in the US and Israel, oversampling tobacco users. The current study analyzed data from participants who responded to the question about HTP awareness or use (n=2061). Multivariable linear and logistic regression analyses examined the relationship between sources of HTP exposure, HTP use, and use intentions.

RESULTS

Among those aware of HTPs, both Israelis and Americans reported past-month HTP media exposure via advertisements (58.2% vs 48.0%), non-advertisement sources (49.7% vs 30.7%), and social connections (51.5% vs 33.6%), respectively. Factors associated with HTP awareness (n=677/2061; 32.9%) included media use frequency (AOR=1.13; 95% CI: 1.01-1.28) and social connections using HTPs (AOR=2.45; 95% CI: 1.92-3.15). Among those aware of HTPs, past-month HTP exposure via digital media advertisements (AOR=2.06; 95% CI: 1.09-3.91) and non-advertising promotion via radio, podcast, movie, television or theatre (AOR=2.30; 95% CI: 1.19-4.44) and websites (AOR=2.36; 95% CI: 1.32-4.21) were associated with current HTP use. Exposure to digital media advertisements (β=0.35; 95% CI: 0.07-0.62) and non-advertising promotion via social media (β=0.62; 95% CI: 0.34-0.91) were correlated with higher use intentions. Having social connections using HTPs was correlated with higher use (AOR=2.21; 95% CI: 1.19-4.11) and intentions (β=0.66; 95% CI: 0.42-0.91). No significant differences were found across countries.

CONCLUSIONS

Digital media (e.g. online, social media) were particularly salient correlates of HTP intentions and use. Future studies are needed that further examine media exposures to these products, as well as that examine possible regulations to limit HTP promotion via these channels.

Particle emissions from heated tobacco products

INTRODUCTION

This study determines the particle emissions from five heated tobacco products (HTPs).

METHODS

An aethalometer is used for the determination of black carbon (BC) and an aerosol monitor for total particulate matter (PM) concentration and also PM fractions (1, 2.5, 4, and 10 μm) in the mainstream emissions of 5 HTPs: IQOS, LIL, PULZE, ILUMA, and GLO. Fifteen different flavors were used, five sticks per flavor, which were smoked using a peristaltic pump under both ISO and Canadian smoking regimes. The method repeatability was determined using 15 sticks of one flavor for each brand for each smoking regime.

RESULTS

All HTPs emit particles, and more than 99.7% of the particles emitted are smaller than 1 μm. Both BC and PM emissions show quite low repeatability. Particle emissions increase in relation to the heating temperature and the intensity smoking regime, and are depending on the flavor used. BC corresponds to a small percentage of total PM.

CONCLUSIONS

Although HTPs are promoted as products of reduced risk compared to conventional cigarettes, high particle concentrations are detected in their emissions, depending on the smoking regime, the flavor used, and the operation parameters. PM emissions vary significantly between different brands under the ISO smoking regime, probably due to the heating temperature. In contrast, PM emissions under the Canadian smoking regime do not vary significantly between different brands. This could probably be attributed to the fact that increased puff frequency does not allow the device to cool down between puffs, resulting in an increase in PM emissions for all the brands, but not dependent on the maximum heating temperature of the device. BC emissions only consist of a very small fraction of PM and do not vary significantly between different brands under both smoking regimes.

What Can Current Biomarker Data Tell Us About the Risks of Lung Cancer Posed by Heated Tobacco Products?

INTRODUCTION

Heated tobacco products (HTPs) are marketed as less harmful alternatives to cigarettes, but the lung cancer risk of HTPs is unknown. In the absence of epidemiological data, assessing the risks of HTPs relies on biomarker data from clinical trials. This study examined existing biomarker data to determine what it tells us about the lung cancer risk posed by HTPs.

AIMS AND METHODS

We identified all biomarkers of exposure and potential harm measured in HTP trials and evaluated their appropriateness based on ideal characteristics for measuring lung cancer risk and tobacco use. The effects of HTPs on the most appropriate biomarkers within cigarette smokers switched to HTPs and compared to continued cigarette smoking or cessation were synthesized.

RESULTS

Sixteen out of eighty-two biomarkers (7 exposure and 9 potential harm) measured in HTP trials have been associated with tobacco use and lung cancer, dose-dependently correlated with smoking, modifiable upon cessation, measured within an appropriate timeframe, and had results published. Three of the exposure biomarkers significantly improved in smokers who switched to HTPs and were not significantly different from cessation. The remaining 13 biomarkers did not improve-in some instances worsening upon switching to HTPs-or were inconsistently affected across studies. There were no appropriate data to estimate the lung cancer risk of HTPs in non-smokers.

CONCLUSIONS

The appropriateness of existing biomarker data in assessing lung cancer risk of HTPs, both relative to cigarettes and their absolute risk, is limited. Furthermore, findings on the most appropriate biomarkers were conflicting across studies and largely showed no improvement following a switch to HTPs.

IMPLICATIONS

Biomarker data are fundamental to assessing the reduced risk potential of HTPs. Our evaluation suggests much of the existing biomarker data on HTPs is inappropriate for determining the risk of lung cancer posed by HTPs. In particular, there is a paucity of data on the absolute lung cancer risk of HTPs, which could be obtained from comparisons to smokers who quit and never smokers exposed to or using HTPs. There is an urgent need for further exploration of the lung cancer risks posed by HTPs, via clinical trials and, in the long-term, confirmation of these risks via epidemiological studies. However, careful consideration should be given to biomarker selection and study design to ensure both are appropriate and will provide valuable data.

Immunology in COPD and the use of combustible cigarettes and heated tobacco products

Chronic obstructive pulmonary disease (COPD) is one of the most common chronic respiratory diseases, characterised by high morbidity and mortality. COPD is characterised by a progressive decline of lung function caused by chronic inflammatory reactions in the lung tissue due to continual exposure to harmful molecules by inhalation. As prevention plays a very important role in COPD, quitting smoking is the most important factor in reducing the decline in lung function. Unfortunately, many people are unable to break their nicotine addiction. This paper summarises current knowledge about combustible cigarettes (CSs) and alternative tobacco products such as heated tobacco products (HTPs) in COPD. The paper focuses on the immunological aspects of COPD and the influence of tobacco products on lung tissue immunology. There are differences in research results between HTPs and CSs in favour of HTPs. More long-term studies are needed to look at the effects of HTPs, especially in COPD. However, there is no doubt that it would be best for patients to give up their nicotine addiction completely.

Assessing and minimizing risk of bias in randomized controlled trials of tobacco cessation interventions: Guidance from the Cochrane Tobacco Addiction Group

The Cochrane Tobacco Addiction Group has created risk of bias tools, which are topic-agnostic. In 2012 the Cochrane Tobacco Addiction Group created guidance specific to considerations for reviews of randomized controlled trials of tobacco cessation interventions, building on existing Cochrane tools. The guidance covers issues relating to selection bias, performance bias, detection bias, attrition bias and selective reporting. In this paper, we set out to make this guidance publicly available, so that others can use and cite it. We provide advice for using this tool to appraise trials critically as a systematic reviewer. We also provide guidance for triallists on ways to use this tool to improve trial design and reporting.

Le tabac chauffé est-il un outil de réduction des risques ?

Heated tobacco (HT), a new tobacco product, is presented by the tobacco industry as an effective and safe alternative to cigarettes. Even if the quantities of harmful compounds emitted by HT are lower than those found in cigarette smoke, this reduction in exposure cannot be equated with a reduction in risk. No study has provided evidence that switching from cigarettes to HT reduces the risk of tobacco-related diseases. HT cannot be considered as a cigarette cessation product and was even designed as a product to initiate or return to tobacco consumption. To promote this product, the tobacco industry essentially exploits the concept of harm reduction and, as such, tries in its commercial communication to create confusion between HT and electronic cigarettes, despite these two products having nothing in common. This promotion is based, on the one hand, on the data of internal studies in contradiction with those of independent studies, and, on the other, illegally, on social networks and communication in contradiction with the statements of regulation authorities. HT is a new lure offered by the tobacco industry, intended to maintain its profits in a world that is moving away from "traditional" cigarettes. It should be strictly advised against for both non-smokers and smokers.