Abstract 11398: Association of Electronic Nicotine Delivery Systems Use with Circulating Angiogenic Cell Levels

Abstract

Background: Circulating Angiogenic Cells (CAC) are known to aid in endothelial repair and are a promising marker of vascular function. Electronic Nicotine Delivery Systems (ENDS) have been hypothesized to impact vascular health, however the association between ENDS and CACs is unknown. Hypothesis: We hypothesize that ENDS use, sole or dual, will be significantly associated with CAC levels. Methods: We analyzed CAC levels of 314 human participants enrolled in the Cardiovascular Injury due to Tobacco Use study, which is a multi-center cross-sectional study of healthy participants 21-45 years age, without known cardiovascular disease or cardiovascular disease risk factors. Four study groups were determined a priori - non-smokers (n=62), sole cigarette users (n=207), sole ENDS users (n=17), and dual users (cigarette and ENDS) (n=28). A total of 15 CACs were measured via a standardized flowcytometry protocol using four cell surface markers - CD146 (endothelial), CD34 (stem cell), CD45 (leukocyte), and ACC133 (early progenitor/stem cell). Regression analysis was conducted using a General Linear Model with gamma distribution and log-link. Model was adjusted for age, sex, race, ethnicity, and enrollment site. Results: Among sole ENDS users, two CACs were significantly higher and four CACs were significantly lower, as compared to referent non-smokers (all P<0.05) (Figure 1-A). Similarly, among dual users, seven CACs were significantly higher and one CAC was significantly lower, as compared to non-smokers (all P<0.05) (Figure 1-B). Conclusion: CACs are sensitive to ENDS use, including dual use. Although CACs with endothelial surface markers were most commonly associated with ENDS/dual use, CACs with stem and early progenitor surface markers were also associated with ENDS/dual use. CACs are promising biomarkers of vascular function and further research is needed to quantify the effect of individual CAC on vascular function.