The acute and chronic impact of pod-based e-cigarettes on vascular health

By Pooja Toshniwal PahariaReviewed by Danielle Ellis, B.Sc.Nov 2 2022

In a recent study soon to be presented at the American Heart Association (AHA) Scientific Sessions 2022*, researchers evaluated the impact of PEC [pod-based electronic (e)-cigarette] usage on cardiovascular (CVS) health under the agenesis of the AHA’s TCORS (tobacco center for regulatory science) group.

*Important notice: Statements and conclusions of studies that are presented at the American Heart Association’s scientific meetings are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. Abstracts presented at the Association’s scientific meetings are not peer-reviewed, rather, they are curated by independent review panels and are considered based on the potential to add to the diversity of scientific issues and views discussed at the meeting. The findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.

The study findings were presented in a meeting held in Chicago from November 5 to November 7, 2022, as part of a premier international discussion of the most recent advancements in scientific research and updates on evidence-based practices in clinical settings pertaining to CVS health.

Background

In recent times, PEC use has increased among young adults and individuals attempting to reduce or quit smoking conventional combustible cigarettes. Cigarettes contain volatile organic compounds (VOCs), a broad category of gases in several commonly used things, such as paints, cleaning products, pesticides, and vehicular exhaust.

The US EPA (United States environmental protection agency) has stated that VOC exposure can cause negative effects on health with varying magnitudes. The long-lasting impacts of using new tobacco-based products have not been well-characterized and warrant further investigation.

About the study

In the present observational and multi-center study, researchers compared the negative effects of VOC exposure on blood vasculature among individuals who used PECs, conventional combustible cigarettes, and no nicotine or tobacco products.

The study comprised 106 young adults (local residents, faculty members, and students) aged between 18 and 45 years, with no CVS illness or associated risk factors (for hypertension, dyslipidemia, or diabetes mellitus type 2. The individuals were enrolled in the study from 2019 to 2021 conducted at the University of Louisville and the University School of Medicine in Kentucky and Boston, respectively. For all participants, HR (heart rate) and BP (blood pressure) were measured before and post-10-minute use of their self-chosen tobacco-based products.

For the study participants, measurements were recorded on a single day during a single clinical visit. Blood vasculature (veins and arteries circulating blood to every part of the body) functioning was assessed by observing flow-mediated brachial artery dilation/widening as a response to an elevation in the flow of blood at two time points, i.e., prior to and 0.5-hour post-tobacco use. VOC levels in urine were recorded prior to and 60 minutes post-usage of either PECs or conventional cigarettes. Nitric oxide (NO) production was measured using a DAF-2 indicator among VOC-exposed HAECs (human aortic endothelial cells).

Results

Among the participants, 51% and 49% were female and male, respectively, and 35%, 33%, and 81% of individuals who smoked PECs, conventional cigarettes, and no tobacco products were females, respectively. Forty-eight (45%), 21 (20%), and 37 (35%) of the study participants used PECs, conventional cigarettes, and no tobacco products, respectively. Among the participants, 37%, 64%, and 36% of PEC users reported non-conventional cigarette use, used electronic cigarettes exclusively, and used both conventional cigarettes and PECs, respectively.

Multiple VOCs released by PECs were found to be linked to blood vasculature health changes, including elevations in BP and HR values and reduced blood vascular dilation. PEC users and conventional cigarette users showed eight percent greater systolic BP and elevated HR values in comparison to non-tobacco users. However, vascular function alterations associated with PEC use and conventional cigarette use were comparable. Amounts of VOCs such as acrylamide, acrolein, crotonaldehyde, and acrylonitrile were linked to vascular alterations. HAEC exposure to acrylamide and acrolein lowered NO production stimulated by acetylcholine.

Conclusions

Overall, the study findings showed that PEC use had comparable short-term and long-lasting impacts on vascular function, BP, and HR as conventional cigarette use among young and healthy adults, including individuals who never smoked conventional cigarettes. The findings indicate that PECs release VOC chemicals that have toxic effects on the blood vasculature, such as altered NO production, which can be detrimental to CVS health.

Setting stringent health regulations that increase PEC procurement and accessibility difficulties for youth is critical to attaining an environment free of tobacco. In addition, improved strategies and approaches are required to aid individuals in quitting tobacco and expanding access and support to tobacco cessation medications and programs.

Study limitations

The limitations of the present study include permitting participants to use their preferred tobacco-based products, thereby increasing the difficulty of characterizing the impact of individual product constituents like nicotine and flavors. In addition, the preferred use of tobacco products would make the ascertainment of inter-individual vascular function differences associated with the use of specific brands or types of tobacco-based products more challenging. Moreover, most of the participants used PECs with a mint flavor. Further research could be conducted with larger sample sizes to evaluate the differences linked to using different PEC flavors.

*Important notice: Statements and conclusions of studies that are presented at the American Heart Association’s scientific meetings are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. Abstracts presented at the Association’s scientific meetings are not peer-reviewed, rather, they are curated by independent review panels and are considered based on the potential to add to the diversity of scientific issues and views discussed at the meeting. The findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.