Exposure to Heated Tobacco Products and Adverse Health Effects, a Systematic Review

Abstract

Heated tobacco products (HTP) are a form of nicotine delivery intended to be an alternative to traditional cigarettes. HTP tobacco products are sold to consumers as a less harmful alternative to traditional cigarettes, both for users and bystanders. The actual impact of HTP on the health of users and its overall impact on public health is still not fully known. A systematic search of the literature was carried out to identify relevant studies published in English from 2015 to February 2021. The following databases were used: PubMed, Scopus, Elsevier and ClinicalKey. 25 studies (independent and sponsored by the tobacco industry) were considered. The analysis of exposure biomarkers and cardiovascular and respiratory biomarkers showed differences between smokers and people using heated tobacco products. Improvements in clinically relevant risk markers, especially cholesterol, sICAM-1, 8-epi-PGF2α, 11-DTX-B2, HDL and FEV1, were observed compared to persistent cigarette smokers. On the other hand, exposure to IQOS has been reported to alter mitochondrial function, which may further exaggerate airway inflammation, airway remodeling and lung cancer. These products have the potential to increase oxidative stress and increase respiratory tract infections by increasing microbial adherence to the respiratory tract. Our review suggests that HTP products may be products with a reduced risk of chronic diseases, including respiratory and cardiovascular diseases and cancer compared to traditional smoking, although in the case of non-smokers so far, they may pose a risk of their occurrence. Research seems to be necessary to assess the frequency of HTP use and its potential negative health effects.

Plasma Cotinine Is Positively Associated with Homocysteine in Smokers but Not in Users of Smokeless Tobacco

“…Heated tobacco products, other than e-cigarettes, have also been introduced into the market. Differences in the clinical risk markers for cardiovascular and respiratory diseases have been noted in a recent review, where users of heated tobacco products had a better biomarker profile compared to persistent smokers [28]. One study reported no short-term changes in tHcy in smokers using conventional cigarettes, randomized to smoking abstinence, menthol cigarettes, or menthol tobacco heating systems (n = 40, 42, and 78, respectively) [29].…”

Use of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes to Predict the Cardiotoxicity Potential of Next Generation Nicotine Products

“…Importantly, long term in vivo and clinical studies with adult smokers that have compared commercialised HTPs with combustible cigarette smoke exposure, have shown significant improvements in cardiovascular endpoints and related biomarkers upon switching from combustible cigarettes to HTPs ( Sakaguchi et al, 2014 ; Ogden et al, 2015 ; Smith et al, 2016 ; Schaller et al, 2016b ; Schaller et al, 2016a ; Pratte et al, 2017 ; Gale et al, 2019 ; Phillips et al, 2019 ; Shein and Jeschke, 2019 ; Tran et al, 2020 ; Wong et al, 2020 ). A recent systematic review of the health effects of HTP by Zynk et al (2021) reported favourable improvements in biomarkers related to cardiovascular and respiratory endpoints when comparing continued combustible cigarette smoking adult smokers who switched to using HTPs ( Znyk et al, 2021 ). Improvements in clinically relevant risk markers, especially cholesterol, sICAM-1, 8-epi-PGF2α, 11-DTX-B2, HDL and FEV1 have been observed when adult smokers switched away from combustible cigarettes to HTPs ( Zynk et al, 2021 ).…”

“…Buchanan et al (2020) undertook a review of the clinical and pre-clinical studies conducted on e-cigarettes and concluded that the studies presented in their review "have shown that e-cigarettes can induce negative cardiovascular effects through various mechanisms such as oxidative stress, inflammation, DNA damage, arterial stiffness, and altered haemodynamics, and platelet activation." Furthermore, recent research suggests that HTP and EVP aerosols can affect the cardiovascular system, albeit it at exposures many magnitudes higher than combustible cigarette cardiotoxic exposures (Abouassali et al, 2021;Qasim et al, 2017;Znyk et al, 2021). The role of NGPs in relation to cardiovascular diseases is however, still a source of debate and controversy (NASEM 2018;Fried and Gardner, 2020;Tsai et al, 2020).…”

“…NASEM (2018) , in their review of e-cigarettes concluded that “There is substantial evidence that components of e-cigarette aerosols can promote formation of reactive oxygen species/oxidative stress. Although this supports the biological plausibility of tissue injury and disease from long-term exposure to e-cigarette aerosols, generation of reactive oxygen species and oxidative stress induction is generally lower from e-cigarettes than from combustible tobacco cigarette smoke.” Buchanan et al (2020) undertook a review of the clinical and pre-clinical studies conducted on e-cigarettes and concluded that the studies presented in their review “have shown that e-cigarettes can induce negative cardiovascular effects through various mechanisms such as oxidative stress, inflammation, DNA damage, arterial stiffness, and altered haemodynamics, and platelet activation.” Furthermore, recent research suggests that HTP and EVP aerosols can affect the cardiovascular system, albeit it at exposures many magnitudes higher than combustible cigarette cardiotoxic exposures ( Abouassali et al, 2021 ; Qasim et al, 2017 ; Znyk et al, 2021 ). The role of NGPs in relation to cardiovascular diseases is however, still a source of debate and controversy ( NASEM 2018 ; Fried and Gardner, 2020 ; Tsai et al, 2020 ).…”

Review of the Existing Evidence for Sex-Specific Relationships between Prenatal Phthalate Exposure and Children’s Neurodevelopment

“…The PRISMA (preferred reporting items for systematic reviews and meta-analyses) was employed to guide this review [ 35 ].…”