Age-Stratified Analysis of the Temporal Association Between the Number of E-cigarettes and/or Cartridges Used at Wave 1 and Marijuana Use at Wave 2 Among Baseline Marijuana Never Users, PATH Study, 2013–2015

Marijuana Never Users at Wave 1Marijuana P12M Use at Wave 2Marijuana Heavy Use at Wave 2
No. E-cigarettes and/or Cartridges Used at Wave 1anaORbnaORb
All adolescents, n = 10 3648971.3 (1.1–1.5)***2861.2 (1.0–1.5)
Aged 12–14 y (n = 5901)3731.7 (1.3–2.0)***1281.6 (1.2–2.2)**
Aged 15–17 y (n = 4463)5241.2 (1.0–1.4)1580.9 (0.7–1.3)
Interaction between e-cigarette use and age groupc1.5 (1.2–1.9)**1.8 (1.2–2.6)**
  • —, not applicable.

  • a A dose-response analysis was conducted by treating the number of e-cigarette cartridges used as an ordinal variable, and aOR corresponds to 1 U increase in the scale.

  • b For all models, aOR was adjusted by sensation seeking, ever use of cigarettes, drinking, nonmedical use of prescription drugs and other illicit drugs, and demographics (sex, race and/or ethnicity, grade performance, parental education, and region) at wave 1.

  • c Significant interaction indicates that that number of e-cigarettes used at baseline was associated with higher risks of marijuana use at wave 2 among younger adolescents than among older adolescents.

  • ** P < .01;

  • *** P < .001.