The Effects of Nicotine Salts on Arterial Hemodynamics and Stiffness in Young Regular Users of E-cigarettes

Background: E-cigarettes emerged on the market as alternative tobacco products popular among the youngest consumers. These products contain a different form of nicotine, known as nicotine salts, with faster absorption into the body than freebase nicotine presented in combustible tobacco. Freebase nicotine has been associated with detrimental changes in arterial hemodynamics and structure, early markers of cardiovascular disease development. Whether nicotine salts impact cardiovascular health is currently unknown. Thus, the purpose of this study was to investigate the effects of nicotine salts from e-cigarettes on arterial hemodynamics and stiffness in regular users of e-cigarettes. Methods: Fourteen young (age: 23±2 y.) apparently healthy, regular users of e-cigarettes participated in the study consisting of an initial visit and a follow-up visit fourteen days after being randomized to either e-cigarettes with or without nicotine, particularly nicotine salts. Cotinine, a derivate of nicotine with a longer half-life, was evaluated to monitor the use. Arterial hemodynamics and stiffness were assessed via applied tonometry before and after the intervention to evaluate systolic (SBP), diastolic (DBP), and mean arterial (MAP) blood pressures as well as pulse-wave velocity (PWV). Results: Following the intervention, a significant ( p= 0.001) difference in cotinine was identified between those who maintained or increased (+C, n=7; Δ=+30±30 ng/mL) and those who decreased (-C, n=7; Δ=-173±115 ng/mL) use of e-cigarettes with nicotine salts. In addition, a significant decrease in arterial stiffness (ΔPWV=-0.59 m/s, p= 0.045) was observed in those who decreased the use of e-cigarettes with nicotine salts while no changes in blood pressure were observed between the groups. Positive associations between the changes in cotinine and changes in hemodynamics including SBP, DBP, and MAP were observed ( r≥ 0.627; p≤ 0.016). Similarly, positive associations between changes in cotinine and changes in arterial stiffness were also identified ( r= 0.575; p= 0.031). To note, changes in arterial stiffness were associated with a changes in SBP ( r= 0.603; p= 0.022), but not DBP or MAP ( r≤ 0.195; p≥ 0.504). Conclusions: Results of the present study suggest that reductions in nicotine-salt exposure from e-cigarettes were associated with reduced arterial stiffness in regular users, inferring that nicotine salts might contribute to adverse arterial changes. Future studies are warranted to further investigate the long-term effects of nicotine salts from regular e-cigarette use on arterial hemodynamics and stiffness. Supported in part by a Rapid Response Project (NIDA/FDA), AHA Predoctoral Fellowship & DC Women's Board This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.