The Effects of Habitual Non-Tobacco Nicotine Consumption on Resting Autonomic Cardiovascular Control in Young Adults: A Pilot Study

Introduction: E-cigarettes and oral nicotine pouches (ONPs) have gained popularity among non-smoking young adults. While the health and cardiovascular consequences of long-term tobacco smoking are well-established, the potential shorter-term effects of non-tobacco nicotine remain unknown. Objectives: To investigate whether non-tobacco nicotine products (e-cigarettes, ONPs) impact cardiovascular markers of autonomic nervous system (ANS) regulation in young adults, and whether a 24-hour nicotine abstinence period could restore physiological responses comparable to controls. Methods: To date, twenty control (CTRL: 10m:10f, 20.8+0.9 years old) and 3 nicotine-using (NIC: 2m:1f, 21.7+1.5 years old; 1-8 years) participants have completed two in-lab visits separated by a one-week monitoring period, with NIC completing an additional third visit following 24-hours of nicotine abstinence (ABS). In-lab visits comprised normal and paced-breathing measurements of heart rate (HR), HR variability (HRV), and blood pressure (BP). Nicotine consumption history and recent exposure were quantified through self-report and urinalysis of nicotine and cotinine by liquid chromatography-mass spectrometry, respectively. Results: At this time of interim analysis, HR was elevated in NIC (n=3) (81.2±18.3 bpm) vs CTRL (n=19) (70.5±10.7 bpm). HRV, e.g. through standard deviation of normal inter-beat intervals (SDNN), was lower in NIC (n=3) (46.9±11.9 ms) vs CTRL (n=18) (63.0±25.1 ms). BP was elevated in NIC (n=3) (125.9+17.0 mmHg) vs CTRL (n=19) (114.3+4.9 mmHg). Cardiovascular indices partially normalized towards control values post-24h nicotine abstinence in NIC. NIC (n=3) had higher nicotine (360+375 ng/mL) and cotinine (844+424 ng/mL) concentrations vs CTRL (n=5) (<13.8 ng/mL for both), with marked reductions following ABS. Conclusion: Preliminary findings suggest non-tobacco nicotine use is associated with altered cardiovascular function in young adults, underscoring the need for further research into non-tobacco nicotine product health effects. Participant recruitment and testing are ongoing to reach an n=20 per group.