Differences in biomarkers of potential harm after 2+ years of tobacco heating system use compared to cigarette smoking: a cross-sectional study.

Abstract

Background: Growing evidence indicates that noncombustible products could be a tobacco harm reduction tool for smokers who do not quit. The Tobacco Heating System (THS) emits substantially lower levels of harmful cigarette smoke constituents, and previous randomized clinical studies showed improved levels of biomarkers of potential harm (BoPH) linked to smoking-related disease.

Methods: In this cross-sectional study of healthy participants (n = 982) who (i) smoked cigarettes, (ii) had voluntarily switched from smoking to THS use, or (iii) formerly smoked, blood and urine samples were assayed for nine BoPH. The co-primary endpoints were carboxyhemoglobin, total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, white blood cells, and 8-epi-prostaglandin-F_2α. The key secondary endpoints were high-density lipoprotein cholesterol, soluble intercellular adhesion molecule-1, 11-dehydrothromboxane B₂, central vascular augmentation index, and forced expiratory volume in 1 s (%predicted post-bronchodilator).

Results: THS users showed significant favorable differences in all nine BoPH compared to current smokers. Results in THS users were similar to those in former smokers.

Conclusion: Compared to current smokers, healthy participants who voluntarily switched from smoking to THS use for ≥2 years in the real world had favorable differences in BoPH related to oxygen delivery, genotoxicity, inflammation, oxidative stress, lipid metabolism, endothelial function, platelet activation, and cardiovascular and respiratory function. Clinicaltrials.gov Identifier: NCT05385055.