Association between age at first reported e‐cigarette use and subsequent regular e‐cigarette, ever cigarette and regular cigarette use

Abstract Background and aims Association of electronic cigarette use subsequent smoking has received considerable attention, although age first not. This study tested differences in regular (e‐cigarettes, cigarettes) ever (cigarettes) between e‐cigarette user groups: early versus never users, late users effects controlling for covariates. Design Prospective with 12‐ 24‐month follow‐up e‐cigarette/cigarette ever/regular data from an intervention. Setting Forty‐five schools England (Staffordshire Yorkshire). Participants Never smokers (3289 13–14‐year‐olds) who were part a cluster randomized controlled trial. Measurements The sample was divided into groups users: (at 13–14 years), 14–15 years) years). Dependent variables self‐reported at 15–16 years. Covariates assessed. Findings Early compared significantly more likely to be [early: odds ratio (OR) = 9.42, 95% confidence interval (CI) 5.38, 16.49, P < 0.001; late: OR 6.89, CI 4.11, 11.54, 0.001], (early: 7.96, 6.02, 10.53, 5.13, 3.85, 6.84, 0.001) 7.80, 3.99, 15.27, 4.34, 1.93, 9.77, Late had lower rates cigarettes years (OR 0.48, 0.35, 0.66, 0.001), this difference non‐significant 12 months after e‐cigarettes 0.89, 0.64, 1.25, 0.498). Controlling covariates did not change the findings. Conclusions Adolescents report using have higher subsequently initiating than adolescents years, that may attributable longer period time initiate former group.