http://jamanetwork.com/journals/jama/article-abstract/2579858
E-cigarette vaping is reported by 37% of US 10th-grade adolescents1 and is associated with subsequent initiation of combustible cigarette smoking.2 Whether individuals who vape and transition to combustible cigarettes are experimenting or progress to more frequent and heavy smoking is unknown. In addition, because some adolescents use e-cigarettes as a smoking cessation aid,3 adolescent smokers who vape could be more likely to reduce their smoking levels over time. Therefore, associations of vaping with subsequent smoking frequency and heaviness pattern among adolescents were examined.