Peer Influence and Use of Electronic Cigarettes among Adolescents and Young Adults: A Meta-Analysis of Prospective Studies

Abstract

Objective: To examine the association between peer use and individual use of EC among adolescents and young adults. Methods: We performed the search strategy on PubMed, EMBASE, and Cochrane. We selected prospective studies reporting adjusted odds ratio (aOR)/relative risk (aRR) with a 95% confidence interval (CI) and conducted a random-effects meta-analysis. Result: Eleven prospective studies were included, involving 32,014 participants in the quantitative analysis. Meta-analysis results showed a significant association between EC use by friends and increased odds of individual EC use (aOR = 1.79, 95% CI 1.43 to 2.25; I2 = 88.2% for ever use; aOR = 2.14, 95% CI 1.52 to 3.01; I2 = 88.5% for current use). In the subgroup meta-analysis of outcomes, having friends who used EC significantly increased the odds of ever- and current EC use. Similar findings were found in the subgroup meta-analyses by age group, region, sample size, study methodological quality, and follow-up time. Conclusion: This study revealed a positive association between individual EC use and friends’ use, especially among those under 18 years, suggesting targeting peer networks to curb the EC epidemic.