Vascular Stress Markers Following Inhalation of Heated Tobacco Products: A Study on Extracellular Vesicles.

The advent of heated tobacco products (HTPs) has introduced new variables in the study of nicotine delivery systems and their health implications. Amidst concerns over cardiovascular effects, this study aims to elucidate the acute impact of HTP inhalation on extracellular vesicles (EV) levels in young, healthy individuals. In this controlled, acute exposure study, 23 young, healthy volunteers were subjected to HTP inhalation. EV levels of endothelial and platelet origin were quantified through flow cytometry before and after exposure. Data analysis was performed using multiple measures ANOVA to assess changes in EV concentrations. Our findings reveal a significant increase in EVs of endothelial and platelet origin following short-term HTP inhalation with nicotine. Notably, no significant change was observed in leukocyte- and neutrophil-derived EVs. This increase in EVs suggests acute vascular stress, with peak levels observed 4 h post-exposure. The rise in endothelial and platelet-derived EVs aligns with documented responses to acute vascular injury, paralleling the effects seen with traditional cigarette and e-cigarette use. Despite HTPs being marketed as safer alternatives, our results indicate that nicotine-containing HTPs may still pose significant vascular risks. These findings contribute to the growing body of evidence cautioning against the perceived safety of HTPs and reinforce the importance of regulatory oversight and public health initiatives targeting nicotine delivery technologies. Trial Registrations: ClinicalTrials.gov ID: NCT04824495, registered 2021-01-07.

Use of heated tobacco products (IQOS) causes an acute increase in arterial stiffness and platelet thrombus formation.

BACKGROUND AND AIMS: Heated tobacco products (HTPs) are novel alternative tobacco products being promoted as an alternative to cigarettes. To evaluate the impact of HTP use on vascular function, we investigated the effects of a brief HTP usage on arterial stiffness and platelet thrombus formation in healthy volunteers. METHODS: In a randomised crossover study, twenty-four healthy young adults with occasional tobacco use smoked the HTP IQOS 3 Multi (Phillip Morris Int.) and "no-exposure" was used as a control, with a wash-out period of at least one week in-between. Arterial stiffness was assessed through pulse wave velocity and pulse wave analysis. Blood samples, collected at baseline and 5 min following exposure, were analysed with the Total-Thrombus-formation analysis system evaluating platelet and fibrin-rich thrombus formation tendency. RESULTS: HTP exposure caused immediate heightened pulse wave velocity (+0.365 m/s, 95% CI: +0.188 to 0.543; p = 0.004) and enhanced augmentation index corrected to heart rate (+6.22%, 95% CI: +2.33 to 10.11; p = 0.003) compared to the no-exposure occasion. Similarly, blood pressure and heart rate transiently increased immediately following HTP inhalation. Platelet thrombus formation significantly increased following HTP exposure (area under the curve +59.5, 95% CI: +25.6 to 93.4; p < 0.001) compared to no-exposure. No effect was seen on fibrin-rich thrombus formation following HTP-exposure. CONCLUSIONS: Brief HTP use in healthy young adults had immediate adverse effects on vascular function resulting in increased arterial stiffness and platelet thrombus formation, known risk factors for the development of atherosclerosis. Further research is needed to address long term health impacts.

Electronic cigarette use in relation to changes in smoking status and respiratory symptoms.

INTRODUCTION: How e-cigarette use relates to changes in smoking status and respiratory symptoms in the population remains controversial. The aim was to study the association between e-cigarette use and, changes in smoking status and changes in respiratory symptoms. METHODS: A prospective, population-based study of random samples of the population (age 16-69 years) was performed within The Obstructive Lung Disease in Northern Sweden (OLIN) study and West Sweden Asthma Study (WSAS). A validated postal questionnaire containing identical questions was used in OLIN and WSAS at baseline in 2006-2008 and at follow-up in 2016. In total, 17325 participated on both occasions. Questions about respiratory symptoms and tobacco smoking were included in both surveys, while e-cigarette use was added in 2016. RESULTS: In 2016, 1.6% used e-cigarettes, and it was significantly more common in persistent tobacco smokers (10.6%), than in those who quit smoking (2.1%), started smoking (7.8%), or had relapsed into tobacco smoking at follow-up (6.4%) (p<0.001). Among current smokers at baseline, tobacco smoking cessation was less common in e-cigarette users than e-cigarette non-users (14.2% vs 47.6%, p<0.001) and there was no association with a reduction in the number of tobacco cigarettes smoked per day. Those who were persistent smokers reported increasing respiratory symptoms. In contrast, the symptoms decreased among those who quit tobacco smoking, but there was no significant difference in respiratory symptoms between quitters with and without e-cigarette use. CONCLUSIONS: E-cigarette use was associated with persistent tobacco smoking and reporting respiratory symptoms. We found no association between e-cigarette use and tobacco smoking cessation, reduction of number of tobacco cigarettes smoked per day or reduction of respiratory symptoms.

Electronic Cigarette Vaping with Nicotine Causes Increased Thrombogenicity and Impaired Microvascular Function in Healthy Volunteers: A Randomised Clinical Trial.

Electronic cigarette (EC) vaping is increasingly popular, despite growing evidence of adverse health effects. To further evaluate the impact of EC use on vascular health, we investigated the effects of brief EC inhalation on flow-dependent thrombus formation and microcirculation in healthy volunteers. The study was performed with a randomised double-blind crossover design. Twenty-two healthy subjects aged between 18 and 45 years with occasional tobacco use were recruited. Subjects inhaled 30 puffs of EC aerosol with and without nicotine on two occasions separated by a wash-out period of at least 1 week. Blood samples were collected at baseline and at 15 and 60 min following exposure and analysed with the Total-Thrombus-formation analysis system evaluating fibrin-rich thrombus formation and platelet thrombus formation in whole blood under flow. Microvascular function was assessed at baseline and 30 min after exposure by laser speckle contrast imaging and iontophoresis of acetylcholine and sodium nitroprusside (SNP) to evaluate the endothelium-dependent and independent pathways of vasodilation. Compared with nicotine free EC aerosol, exposure to EC aerosol with nicotine significantly increased platelet thrombus formation and fibrin-rich thrombus formation at 15 min (p = 0.017 and p = 0.037, respectively) with normalisation after 60 min. Peak SNP-mediated microvascular perfusion, i.e. endothelium-independent vasodilation, was reduced following EC vaping with nicotine compared with baseline (p = 0.006). Thirty puffs of EC aerosol with nicotine increased platelet and fibrin-dependent thrombus formation and reduced microvascular dilatation capacity. No compelling effects of EC vaping without nicotine were observed, indicating nicotine as the main effector. Trial registration: ClinicalTrials.gov Identifier: NCT04175457 URL: https://clinicaltrials.gov/ct2/show/NCT04175457.