Abstract

Background/Aims: The increasing use of electronic cigarettes (e-cigs) has resulted in complex tobacco use patterns that may change with time within individuals. We developed a mobile platform to capture use patterns and transitions over time in young adults. Methods: Individuals 18-45 years old in the Cardiovascular Injury Due to Tobacco Use (CITU 2.0) study completed a detailed baseline questionnaire followed by enrollment in a text message-based mobile platform (Agile Health, Inc) that collected self-reported tobacco use patterns and transitions over 24 months. Baseline use patterns (sole e-cig use, sole combustible cigarette use, dual use, and non-use) and transitions (changing from one use group to another) monthly until last follow-up are reported. Models were used to predict likelihood of non-use (no tobacco products) or non-combustible use (sole e-cig or non-use) at follow-up. Results: 264 individuals were enrolled at baseline: 87 sole e-cig users, 46 sole combustible users, 91 dual users, and 40 non-users. On monthly follow-ups, the dual use pattern was associated with the highest rate of cumulative transitions, 3 by 6 months, compared to 1 for sole e-cig use. By last follow-up, 65% of the dual use pattern transitioned compared to relatively stable use in the sole e-cig and combustible cigarette use groups (Figure). Rate of uptake of combustible cigarette use in sole e-cig users was low (6%). In logistic regression models, compared to combustible cigarette users, dual users were more likely to make a transition (OR 5.9, p<0.0001), but not sole e-cig users (OR 1.7, p=0.2). Neither group of e-cig users had a higher rate of transition to non-use than combustible cigarette users (dual use OR 1.2, p=0.7, sole e-cig OR 2.1, p=0.1). However, rates of non-combustible use at follow-up were higher in both sole e-cig (OR 55.5, p<0.0001) and dual users (OR 3.2, p=0.006). Conclusions: Frequent longitudinal assessment of tobacco use patterns revealed important details regarding rates of transitions with highest levels amongst dual users of e-cig and combustible cigarettes. Rates of transition to non-use were low across all tobacco product users, with higher rates of transition to non-combustible use amongst dual users when compared to combustible users. Future studies will be important to understand methods to enhance tobacco product cessation amongst all use groups.