Injury Risk and Influencing Factors of Substance Use and Problematic Internet Use Among Emerging Adults in Beijing, China.

Background This study aimed to explore the impact of substance use (SU), problematic internet use (PIU), and their comorbidity on unintentional and intentional injuries among emerging adults in Beijing. Methods This cross-sectional study targeted emerging adults from two universities (undergraduates and postgraduates) in Beijing to ensure comprehension ability and voluntary participation. Commencing in July 2023, an on-site survey employed an anonymous electronic questionnaire accessible through a QR code. Descriptive measures, analysis of variance (ANOVA), chi-square tests, and logistic regression were used for statistical analysis. Logistic regression analyses were used to explore the risk of injury in different populations and to further analyze the factors influencing injury in different populations. Results Among the 1629 participants, substance use was categorized into 1045 low-risk (64.15%), 525 medium-risk (32.22%), and 59 (3.62%) high-risk users. For problematic internet use, participants were divided into non-PIU (n = 777, 47.70%), mild-moderate PIU (n = 819, 50.28%), and severe PIU (n = 33, 2.02%) groups. The comorbid group had a significantly greater risk of intentional injuries, with an adjusted odds ratio (aOR) of 2.08 (95% CI: 1.44–3.01). Patients in the comorbid group demonstrated increased risks of non-suicidal self-injury (NSSI) and suicidal ideation. The comorbid group had the highest risk for NSSI (aOR = 6.75, 95% CI = 3.15–14.48) and suicidal ideation (aOR = 3.49, 95% CI = 2.54–4.81). The demographic, psychological and social factors associated with injury risk varied among substance use, problematic internet use, and comorbid groups. Conclusion This study unveiled the prevalence of substance use and problematic internet use, each manifesting distinct risk profiles, among individuals in the emerging adulthood stage. Both substance use and problematic internet use independently contributed to increased risks of non-suicidal self-injury and suicidal ideation. Notably, the comorbid group faced the highest vulnerability, emphasizing the compounding effect of these behaviors. Improving the mental health of young people, the quality of their sleep, appropriate stress release and the control of bullying in schools may play a significant role in the occurrence of intentional injuries. Furthermore, it is even more important to intervene with emerging adulthood who are younger, live in urban areas, have neurotic personalities and female groups.