E-cigarette Product Characteristics and Subsequent Frequency of Cigarette Smoking.

Introduction:
This text presents the results of a study examining the relationship between electronic cigarette (e-cigarette) product characteristics and the number of cigarettes smoked in the past 30 days at follow-up among young adults in the Southern California Children's Health Study. The study aims to inform regulatory strategies by identifying product characteristics that may impact transitions to heavier patterns of combustible cigarette use.

Key Points:

* The study collected data from students participating in the Southern California Children's Health Study from 2015-2016 (baseline) and 2016-2017 (follow-up).
* The study evaluated the association of three non-mutually exclusive characteristics of e-cigarettes (device type, use of nicotine in electronic liquid, and use for dripping) with the number of cigarettes smoked in the past 30 days at follow-up.
* After adjustment for sociodemographic characteristics, baseline frequency of cigarette smoking, and number of days of e-cigarette use, mod users smoked more cigarettes in the past 30 days at follow-up compared to vape pen users.
* Nicotine e-liquid and dripping were not associated with frequency of cigarette smoking after adjustment for device.
* Participants who reported previous or past-30-day e-cigarette use at baseline reported a higher average number of cigarettes smoked in the past 30 days at follow-up.
* Similar patterns were observed for the association of baseline cigarette use with subsequent smoking frequency.
* The study controlled for sex, race and/or ethnicity, parental education, log-transformed number of cigarettes at baseline, e-cigarette use at follow-up, and number of days of e-cigarette use in the past 30 days at baseline.
* A random effect for community was included when statistically significant.

Main Message:
The study suggests that regulation of e-cigarette product characteristics, specifically device type, warrants consideration as a strategy to reduce cigarette smoking among adolescents and young adults who vape. The results indicate that young adults using modifiable (versus penlike) e-cigarette devices at baseline smoked more cigarettes in the past 30 days at follow-up. By identifying and addressing product characteristics that may increase the risk of transitioning to heavier patterns of combustible cigarette use, regulatory authorities can work towards reducing the overall adverse public health burden of e-cigarettes in adolescent and young adult populations.

Barrington-Trimis JL, Yang Z, Schiff S, et al. E-cigarette Product Characteristics and Subsequent Frequency of Cigarette Smoking. Pediatrics. 2020;145(5). doi:10.1542/peds.2019-1652