12-14% of individuals who try e-cigarettes become daily users. (Schoenborn and Gindi., 2015)
More than 20% of 18-24 year olds have tried e-cigs. (Schoenborn and Gindi., 2015).
Carnevale and colleagues discovered electronic cigarette vapor reduced arterial function during reactive hyperemia immediately following e-cigarette exposure. (Carnevale et al., 2016)
A 2016 study by Vlachopoulos et al., found that aortic stiffness and blood pressure both increased after electronic cigarette use in a sample of young smokers.
Tobacco has been linked to increased risk of heart disease and stroke. The inhalation of combusted chemicals leads to damage of the arterial wall which in turn leads to greater deposits of plaque.
At this level you will allow me to compensate 100% of the subjects needed for this study to have adequate statistical power.