Abstract
OBJECTIVE: Non-suicidal self-injury (NSSI) constitutes an important public health concern. Here, we systematically reviewed and synthesized existing literature to provide an up-to-date overview of associations between NSSI, problem gambling, problem gaming, and problematic internet use (PIU). METHODS: We searched four databases through April 2025: Web of Science, Scopus, PubMed, and PsycINFO. The Joanna Briggs Institute's tool was used to assess the quality of studies. Empirical studies utilizing quantitative or qualitative methods or case studies that presented evidence on the relationships between NSSI and frequent or problematic gambling, internet use, and gaming were included. RESULTS: Forty studies published between 2009 and 2025 were reviewed. Four investigated the relationship between NSSI and problem gambling, seven focused on problem gaming, and twenty-nine examined PIU. Cross-sectional designs and surveys were common. Findings suggest that at-risk or problem gambling was associated with NSSI in adolescents, college students, and adults. An association between PIU and NSSI appeared moderated by social support, with impulsivity representing a shared factor. Similarly, internet gaming disorder and its severity were linked to NSSI, with anxiety acting both as a mediator and moderator. Limitations entailed self-reported measures, limited generalizability, poor ability to establish causal relationships due to cross-sectional designs, and frequent use of single unvalidated questions to assess NSSI. CONCLUSION: The review provides a comprehensive overview and suggests complex relationships between NSSI and problem gambling, problem gaming, and PIU. Clinicians and future studies should focus on co-occurring disorders and identify risk factors, predictors, and moderators that influence these relationships.