the cardiovascular effects of electronic hookah vaping

Conditions: Endothelial Dysfunction; Inflammation; Oxidative Stress

Summary: hookah (water-pipe) tobacco smoking has quickly grown to become a major global tobacco epidemic among youth; with electronic (e-) hookahs more recently increasing in popularity especially among young female adults, who endorse marketing claims that these products are a safer alternative to traditional hookah, but scientific evidence is lacking. the study aims to elucidate the comparative effects of traditional hookah smoking vs. e-hookah vaping on human vascular and endothelial function; and examine the role of inflammation and oxidative stress, as likely mechanisms in hookah-related cardiovascular disease pathogenesis.

hookah (water-pipe) tobacco smoking is rapidly increasing in popularity worldwide. contributing to this popularity is the unsubstantiated belief that traditional charcoal-heated hookah smoke is detoxified as it passes through the water-filled basin. more recently, electronic (e-) hookahs-containing flavored e-liquid that is heated electrically but inhaled through traditional water-pipes-are increasing in popularity in the united states among young female adults, who endorse marketing claims that these products are even safer than traditional charcoal-heated hookah products. the objective of this project is to investigate the comparative effects of traditional charcoal-heated hookah smoking versus e-hookah vaping on endothelial and vascular function and their mechanistic role in the development of cardiovascular disease. the investigators will test the hypothesis that: 1) in the absence of burning charcoal briquettes and virtually any carbon monoxide (co) exposure, e-hookah vaping acutely impairs endothelial function and evokes acute central arterial stiffness, opposite from the endothelial function augmentation observed after traditional charcoal-heated hookah smoking, which is likely mediated by the large co boost emitted from burning charcoal briquettes used to heat the flavored hookah tobacco; and 2) the processes of oxidative stress and inflammation play a pivotal mechanistic role underlying these vascular changes. accordingly, in a cross-over study comparing traditional hookah smoking to e-hookah vaping, the investigators will assess endothelial function measured by brachial artery flow-mediated dilation and aortic stiffness by pulse wave velocity and augmentation index in 18 young healthy hookah smokers 21-39 years old, before and after ad lib 30-minute smoking/ vaping exposure sessions. to test for oxidative stress mediation, the investigators will determine if any acute impairment in endothelial function after e-hookah can be prevented by intravenous vitamin c infusion, a potent anti-oxidant. inflammatory and oxidant biomarkers, as well as smoking exposure biomarkers will be collected before and after the exposure sessions. the results of this proposal: (a) stand to fill in gaps in our mechanistic understanding of the comparative effect of traditional vs. e-hookah bowl on vascular and endothelial function; and (b) help inform policy decisions by the fda about regulation of hookah products.

Eligibility criteria:
inclusion criteria: * 21-39 years old hookah smokers: smoked hookah \>12x in last 12 months * no history of illicit drugs or marijuana * no evidence of cardiopulmonary disease by history/ physical * no diabetes: fasting blood glucose \<100 mg/dl * bp\<140/90mmhg * resting hr\<100 bpm * bmi\<30kg•m2 * no prescription medication exclusion criteria: * exhaled co\>10 ppm (smoking non-abstinence) * positive pregnancy test * psychiatric illness