Abstract 16035: Impairment of Endothelial Function by Inhalation of Heat-Not-Burn Tobacco Aerosol
Introduction: “Heat-not-burn” (HNB) tobacco devices heat tobacco at temperatures that avoid combustion but cause the nicotine to aerosolize, leaving the leaf material intact but depleted of volatile substances. A new HNB product, iQOS, from Philip Morris, has been test marketed in several non-US countries and has been considerably more successful than previously introduced HNB products. Despite harm reduction claims by the tobacco industry, the health effects of HNB products are still poorly understood. We have previously shown that exposure to secondhand smoke of cigarettes, little cigars, and marijuana impairs arterial flow-mediated dilation (FMD) in rats. Here, we studied the effect of iQOS mainstream aerosol on endothelial function using our previously established rat model for FMD.
Hypothesis: Exposure to iQOS aerosol impairs endothelial function.
Methods: We exposed rats (n=8/group) via nose cone to 15 seconds of iQOS aerosol, Marlboro cigarette mainstream smoke, or air 10 times over 5 min using a syringe pump to generate and deliver aerosol. FMD was quantitated pre- and post-exposure by measuring femoral artery diameter with micro-ultrasound before and after 5 min of transient surgically induced ischemia, and expressed as the percent vasodilation. Pre- vs. post-exposure FMD differences were evaluated by 2-tailed paired t tests.
Results: FMD was impaired by exposure to iQOS aerosol (10.6±2.9(SD)% vs. 4.5±1.9%, p=.0008) and cigarette smoke (10.6±2.0% vs. 4.6±1.3%, p=.0004) (see figure; each colored line denotes an individual rat pre- and post-exposure; horizontal bars show mean values). FMD was not affected in the clean air controls (8.3±1.9% vs. 8.8±4.5%, p= .82).
Conclusion: Acute exposure to iQOS aerosol can substantially impair endothelial function in rats comparably to cigarette smoke despite the absence of combustion. Use of HNB tobacco products does not necessarily avoid the adverse cardiovascular effects of smoking cigarettes.
Author Disclosures: P. Nabavizadeh: None. J. Liu: None. S. Ibrahim: None. M.L. Springer: None.
- © 2017 by American Heart Association, Inc.