Objectives: Prior evidence reported inconsistently that there is an association between e-cigarette use and suicidal behaviours. The aim of this study was to systematically review the recent literature that explored the association between e-cigarette use and suicidal behaviour such as ideation, planning and attempts. Methods: PubMed and Web of Science databases were searched to include studies between 2017 to 2021. Two reviewers screened all studies and narrative data synthesis was conducted. Results: This review analysed eight cross-sectional studies, which involved a total of 6,84,478 participants where only 4.9% were e-cigarette users (33,714 of 6,84,478). The suicidal ideation/thoughts, planning and attempts were measured among e-cigarette users based on diverse variables such as smoking status, gender, asthmatic, and depressive conditions. Suicidal ideation/thoughts, planning and attempts were higher among male, smoker, asthmatic, and depressive e-cigarette users than lifetime and never e-cigarette users. Conclusions: Public health researchers and policymaker should consider these variables as crucial factors to design any intervention or helpline services to prevent suicidal behaviour among e-cigarette users.
