Nicotine Dependence from Different E-Cigarette Devices and Combustible Cigarettes among US Adolescent and Young Adult Users.

E-cigarettes, the most popular tobacco product among adolescents, vary widely in design and nicotine composition; thus, different devices may have different addictive potential. However, few studies examine levels of nicotine dependence across devices among adolescent and young adult (AYA) e-cigarette users. To assess the extent of nicotine dependence among US AYA (ages 13-24) by e-cigarette device type, we conducted a large, national, cross-sectional survey (n = 4351) and used the Hooked on Nicotine Checklist (HONC) to assess levels of nicotine dependence among those who had used disposable, pod-based, and/or mods/other e-cigarette devices in the past 30 days. We also examined HONC scores among those who had used combustible cigarettes in the past 30 days, whether with or without using e-cigarettes. Patterns of nicotine dependence were comparable across those who had used a combustible cigarette and/or e-cigarette in the past 30 days, with 91.4% of combustible cigarette users, 80.7% of disposable e-cigarette users, 83.1% of pod-based e-cigarette users, and 82.5% of mods/other e-cigarette users showing signs of nicotine dependence, as measured by endorsing at least one HONC symptom. This pattern persisted when analyses were restricted to e-cigarette only users, with more than 70% of all e-cigarette only past-30-day users endorsing at least one HONC symptom, across all types of devices. A thorough understanding of the extent and presentation of nicotine dependence among AYA will help researchers, public health officials, and clinicians recognize and manage AYA nicotine dependence.