P3818Association between e-cigarette use and myocardial infarction: analysis of two large population-representative studies in USA
Abstract Background Smoking is a major risk factor for cardiovascular disease. E-cigarettes are an emerging and controversial public health issue. It is unknown how e-cigarette use affects cardiovascular disease. Purpose In this study, we examine the association between e-cigarette use and myocardial infarction (MI) in two large population-representative studies in USA. Methods The study analyzed the 2016 and 2017 (pooled) National Health Interview Survey (NHIS, N=59,770) and the 2017 Behavioral Risk Factor Surveillance System survey (BRFSS, N=450,016). Proportions (95% CI) were calculated and logistic regression analyses were performed to identify the association between e-cigarette use and MI. Independent variables in the models were demographics, e-cigarette use (daily, some days, former, never), smoking status (daily, some days, former, never) and risk factors for MI (hyperlipidemia, hypertension, diabetes, BMI). Exercise was also introduced as an independent variable, where available (BRFSS only). Results In NHIS, 90.9% (88.8–93.0%) of daily e-cigarette users were current or former smokers. The respective proportion in BRFSS was 86.3% (85.3–87.3%). The majority of some days and former e-cigarette users (≥70%) were also current or former smokers in both surveys. MI was reported by 4.2% (2.7–5.7%) of daily vs. 3.2% (3.0–3.4%) of never e-cigarette users in NHIS (P=NS), and 4.2% (3.5–6.1%) vs. 4.4% (4.2–4.5%) in BRFSS (P=NS), respectively. In NHIS, daily e-cigarette use was not associated with MI (OR: 1.59, 95% CI: 0.97–2.61, P=0.067). Some days and former e-cigarette use were also not associated with MI. In the BRFSS, daily e-cigarette use was not associated with MI (OR: 1.40, 95% CI: 0.96–2.04, P=0.077), but some days (OR: 1.51, 95% CI: 1.09–2.11, P=0.014) and former e-cigarette use (OR: 1.14, 95% CI: 1.02–1.28, P=0.021) were associated with MI. In both surveys, all patterns of smoking (daily, some days and former smoking) and established risk factors (hypertension, hyperlipidemia, diabetes) were consistently and strongly associated with MI. ORs for MI Conclusion E-cigarettes are predominantly used by current and former smokers. Daily e-cigarette use was not associated with having had an MI, while inconsistent and seemingly paradoxical associations are observed for some days and former e-cigarette use. Long-term epidemiological studies are needed to examine how e-cigarette use affects the risk of MI, considering the complex interactions between smoking and e-cigarette use. Acknowledgement/Funding None