Trends in E-cigarette Use in Callers to the Wisconsin Tobacco Quit Line.

E-cigarette use among callers to the Wisconsin Tobacco Quit Line has increased, driven largely by young adults. Most e-cigarette users who call the quit line want to quit. Thus, quit lines can serve an important role in e-cigarette cessation. A better understanding of strategies to help e-cigarette users quit is needed, particularly in young adult callers.