Electronic cigarette use is negatively associated with body mass index: An observational study of electronic medical records

OBJECTIVE: Vaping is advertised as a method to mitigate weight gain after smoking cessation; however, while there is an established inverse association between conventional tobacco use and body mass index (BMI), there is little research on the relationship between e‐cigarettes and BMI. This research tested whether e‐cigarette use was associated with BMI. METHODS: A secondary data analysis of 207,117 electronic medical records from the UAB was conducted. Patient data from 1 September 2017 through 1 June 2018 were extracted. To be included in the analysis, a patient's record had to include measures of e‐cigarette use and key sociodemographic information. Ordinary least squares regression was used to test the association between e‐cigarette use and BMI, controlling for covariates; unconditional quantile regression was used to determine whether the association varied by BMI quantile. For comparison with tobacco smoking, the association between current tobacco smoking and BMI was estimated in a sample from the same population. RESULTS: Respondents in the sample had an average BMI of 30.8 and average age of 50.0 years when BMI was measured. The sample was 51% female, 49.7% white, 46.7% black, and 1.0% Hispanic; 16.4% of the sample had less than a college education and approximately 5% reported currently using e‐cigarettes. Individuals who reported using e‐cigarettes had, on average, a lower BMI compared to those who did not report currently using e‐cigarettes; results indicated that this association did not significantly vary by BMI quantile. Individuals who reported being current smokers had a lower BMI, on average. CONCLUSION: These findings suggest that using e‐cigarettes is associated with a lower BMI in a population of individuals seeking health care, consistent with the association between conventional tobacco use and BMI. This study is a springboard for future research investigating the associations between e‐cigarette use, BMI, and risk of obesity in the general population.