Heat-not-burn Tobacco Products and the Increased Risk for Poly-tobacco Use.

In this study, we tested the use of ecigarette, cigarette, and dual use of both as predictors of heat-not-burn (HNB) tobacco product use onset among young adults, and examined common predictors of smoking cessation as predictors of HNB product use. We collected data from 2229 young adults [mean age = 21.1 (SD = 2.1); 55% women] in Hawaii, at 2 time-points 6 months apart. Current cigarette-only use was the strongest concurrent predictor of HNB product use, followed by dual use, and ecigarette-only use. Among HNB product never users at Wave 1, dual and ecigarette-only use at Wave 1 significantly predicted HNB product use onset at Wave 2. Among cigarette smokers who had never used an HNB product at Wave 1, current use of ecigarette for help with smoking cessation predicted increased odds of HNB product use at 6-month follow-up. Although promoted as a safer alternative for exclusive cigarette smokers, HNB products may increase the risk of dual or poly-tobacco product use among young adults, including current exclusive e-cigarette users. Surveillance of HNB product use as a modified risk tobacco product may need to consider the effects of HNB products on poly-tobacco use among young people.