The association between e-cigarette use and dyslipidemia: A systematic review and meta-analysis of observational studies

E-cigarette use, also known as vaping, has rapidly increased in recent years, often marketed as a safer alternative to traditional smoking. While the cardiovascular risks of vaping are increasingly being recognized, its relationship with dyslipidemia remains unclear. This systematic review and meta-analysis evaluated the association between e-cigarette use and serum lipid levels, specifically total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), and triglycerides (TG).

A search of PubMed, Scopus, EMBASE, CENTRAL, CINAHL, medRxiv, and Google Scholar was conducted up to May 31,2025. Eligible studies included adult populations and assessed the association between exclusive e-cigarette use and lipids. Study quality was assessed using the Methodological Standards for Epidemiological Research (MASTER) scale. Meta-analysis of adjusted odds ratios (aOR) for dyslipidemia and unadjusted weighted mean differences (uWMD) for each lipid was conducted using a bias-adjusted inverse-variance heterogeneity method. Heterogeneity was assessed using the I2 statistic, and publication bias using Doi plots and the LFK index, with the LFK index used as the primary quantitative criterion. Planned subgroup analyses by age group and sex could not be performed due to insufficient stratified reporting in included studies. The overall quality of evidence for each lipid outcome was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework.