A systematic review on risk factors and reasons for e-cigarette use in adolescents.

introductionThe aim was to establish EC use risk and protective factors, the reasons for use, associations with tobacco and other substance use, and use for smoking cessation.

methodsA systematic review following PRISMA guidelines was registered in PROSPERO (CRD42024532771). Searches in Web of Science and PubMed/MEDLINE (March-April 2024) used terms like 'electronic cigarette' and 'adolescents' with a PICO framework. Inclusion criteria covered studies on adolescents aged 10-19 years, published in English or Spanish (2018-2024). Three reviewers independently screened studies, achieving 96% inter-rater reliability. Data extraction followed standardized tables, and methodological quality was assessed using MMAT and GRADE tools, ensuring a robust evaluation of evidence on adolescent electronic cigarette use.

resultsFrom 895 studies, 50 met the inclusion criteria. The strongest risk factors for adolescent EC use include social acceptance and use within peer or family circles (13 studies), male gender (10 studies), low risk perception (6 studies), younger age (3 studies), and greater financial resources (3 studies). Motives for use include low perceived risk and appealing flavors, supported by both longitudinal and cross-sectional studies. EC use is significantly associated with smoking initiation (7 studies), cannabis consumption (8 studies), and alcohol use (4 studies). Evidence on the effectiveness of ECs as harm reduction or smoking cessation tools in adolescents remains inconclusive, with some cross-sectional studies supporting their utility and others finding contrary evidence. High-quality research indicates ECs are predominantly used alongside traditional cigarettes, with dual nicotine consumption patterns commonly observed.

conclusionsEvidence on adolescent EC use identifies risk factors, motives, and links to substance use. However, its role in harm reduction and smoking cessation remains insufficient and controversial. High-quality research is needed, as most studies are low quality. Targeted prevention strategies addressing social influences, perceptions, and accessibility are crucial to reduce adolescent EC use.