Association between perceived relative harm of electronic cigarettes versus cigarettes on nicotine or tobacco use patterns in young adults: findings from the PATH study

INTRODUCTION: As public awareness of potential risks of e-cigarette use grows, young adults may forgo using e-cigarettes in favor of cigarettes or alternative nicotine or tobacco products (NTP). We examined the association between relative harms of e-cigarettes versus cigarettes and NTP use patterns in young adults. METHODS: We conducted a prospective analysis of data from n=2,180 young adults (ages 18-24) who reported past 30-day NTP use in the Population Assessment of Tobacco and Health (PATH) Study. Perceived relative harm of e-cigarettes vs. cigarettes was assessed at Wave 6 (2021). Individuals were classified as having reduced harm perceptions or no reduced harm perceptions. NTP use was assessed at Wave 7 (2022-23). We used adjusted multinomial logistic regression to estimate relative risk ratios (RRRs), with exclusive e-cigarette use as the reference group. RESULTS: At Wave 6, 69.4% of young adults reported no reduced harm perceptions. In adjusted models, young adults with no reduced harm perceptions (vs. those with reduced harm perceptions) had a higher likelihood of reporting past-30-day NTP abstinence (RRR=1.60, 95% CI:1.04-2.40), exclusive cigarette use (RR=3.81, 95% CI:1.73-8.39), or exclusive alternative NTP use (RRR=1.77, 95% CI:1.00-3.13), each compared to exclusive e-cigarette use. CONCLUSION: As perceptions shift toward viewing e-cigarettes as equally harmful as cigarettes, some young adults may abstain from NTP use; however, others may transition toward combustible cigarette use or other NTPs. This pattern suggests that factors which contribute to these types of beliefs may prompt product discontinuation amongst some but also inadvertently encourage shifts toward harmful NTP use patterns.