Early onset of e-cigarette use and subsequent use frequency among US high school students.

OBJECTIVE

The aim of this study was to examine whether the age of e-cigarette use onset predicts subsequent use of e-cigarettes.

METHODS

We used the National Youth Tobacco Survey (NYTS) from 2022. Our sample consisted of 4537 US high school students who had ever used e-cigarettes. Age of first e-cigarette use was assessed by a categorical variable ( 12 years, 13 years, 14 years, 15 years, 16 years, and 17 years). We also constructed a binary variable of early onset use ( 14 years vs 14 years). -cigarette use outcomes in the past 30 days included any use and frequent use (used on 20 days). Weighted multivariable logistic regressions were conducted for each outcome to assess the associations between early onset of e-cigarette use and subsequent use frequency, adjusting for a list of covariates.

RESULTS

Among 4537 high school students who had ever used e-cigarettes, 49.5 % (95 % CI, 46.1 %-52.9 %) reported any use in the past 30 days and 22.8 % (95 % CI, 20.0 %-25.7 %) reported frequent e-cigarette use. Early-onset users, compared with those who tried e-cigarettes at age 14 or older, showed significantly higher risks of any use (aRR = 1.21, 95 % CI, 1.11-1.33) and frequent use (aRR = 1.88, 95 % CI, 1.60-2.20) in the past 30 days. We found younger age at first use to be associated with higher risk of current and frequent use.

CONCLUSIONS

Our findings highlight the importance for age-sensitive efforts, prioritizing younger adolescents, to prevent and delay e-cigarette use initiation.