The Cardiovascular Effects of Electronic Hookah Vaping
Condition: Endothelial Dysfunction; Inflammation; Oxidative Stress
MeSH terms: Inflammation
Study type: Interventional

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.
    

Detailed description: 
      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.
    

Intervention name(s): Traditional hookah smoking; Electronic hookah vaping
Intervention type(s): Other; Other
Intervention description(s): Charcoal-heated hookah smoking; Electronic hookah bowl inhalation
Other intervention name(s): Combustible hookah smoking
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Charcoal-heated hookah smoking vs. electronic hookah vaping
Masking: None (Open Label)
Primary purpose: Other