Introduction Electronic cigarettes (e-cigarettes) are promoted as a less risky alternative to conventional cigarettes and have grown in popularity. Experimental and clinical evidence suggests that they could increase the risk of myocardial infarction.

Methods The National Health Interview Surveys of 2014 (n=36,697) and 2016 (n=33,028) were used to examine the cross-sectional association between e-cigarette use (never, former, some days, daily) and cigarette smoking (same categories) and myocardial infarction in a single logistic regression model that also included demographics (age, gender, BMI) and health characteristics (hypertension, diabetes, and hypercholesterolemia) using logistic regression. Data were collected in 2014 and 2016 and analyzed in 2017 and 2018.

Results Daily e-cigarette use was independently associated with increased odds of having had a myocardial infarction (OR=1.79, 95% CI=1.20, 2.66, p=0.004) as was daily conventional cigarette smoking (OR=2.72, 95% CI=2.29, 3.24, p<0.001). Former and some day e-cigarette use were not significantly associated with having had a myocardial infarction (p=0.608 and p=0.392) whereas former (OR=1.70, p<0.001) and some day cigarette smoking (OR=2.36, p<0.001) were. Odds of a myocardial infarction were also increased with history of hypertension (OR=2.32, p<0.001); high cholesterol (OR=2.36, p<0.001); and diabetes (OR=1.77, p<0.001); and age (OR=1.65 per 10 years, p<0.001). Women (OR=0.47, p<0.001) had lower odds of myocardial infarction.