Mobile Phone Addiction and Suicidal Behaviors in Adolescents: School-Based Cross-Sectional Study in Zhejiang Province, China

Background: Suicide is a critical public health issue in adolescents. Mobile phone addiction (MPA) is characterized by an impaired ability to use mobile phones appropriately, which may further induce addictive symptoms analogous to those of substance abuse disorders and exhibit a significant association with suicidal behaviors. However, the associations between MPA and suicidal behaviors have been inconsistent across previous studies in adolescents. Objective: This study aimed to investigate the association between MPA and suicidal behaviors and to explore the potential mediating roles of sleep quality, depression, and anxiety. Methods: A total of 27,070 adolescents aged 10-19 years were enrolled from a cross-sectional survey with a multistage cluster sampling method across 376 schools in Zhejiang Province, China. A total of 26,394 adolescents with complete data were included in the final analysis. MPA assessed by the Mobile Phone Addiction Index, mobile phone ownership, suicidal behaviors (including suicide ideation, plans, and attempts), sleep duration, depression assessed by Patient Health Questionnaire 9-Item Scale, and anxiety assessed by Generalized Anxiety Disorder 7-Item Scale were obtained from a self-administered questionnaire. Multinomial logistic regression was used to examine the associations of mobile phone ownership and MPA with suicide behaviors. Multivariate linear regression was used to assess the potential mediating effect of sleep duration, depression, and anxiety on these associations. Results: MPA was identified in 4350 (16.5%) adolescents, and 22,299 (84.5%) reported mobile phone ownership. A history of suicidal ideation was reported by 3187 (12.1%) adolescents, suicide plans by 1378 (5.2%), and suicide attempts by 538 (2%). After adjusting for potential confounders, MPA was significantly associated with increased odds of suicide ideation (odds ratio [OR] 2.449, 95% CI 2.236-2.683) and suicide attempts (OR 3.934, 95% CI 3.263-4.743) compared to the normal. Compared to the suicide ideations, MPA had a 1.45 times higher odds of having suicide plans (OR 1.453, 95% CI 1.265-1.669). Compared to adolescents who had neither mobile phone ownership nor MPA, MPA without mobile phone ownership had significantly higher suicidal scores (β coefficient=0.498, 95% CI 0.407-0.588). Mediation analysis indicated that sleep duration (β coefficient=–0.055, 95% CI –0.060 to –0.050), depression (β coefficient=0.952, 95% CI 0.927-0.977), and anxiety (β coefficient=1.141, 95% CI 1.130-1.152) partially mediated the association between MPA and suicidality. Conclusions: MPA was dependently associated with suicidal behaviors in adolescents, with sleep duration, depression, and anxiety partially mediating this association. MPA without mobile phone ownership was related to a higher suicidal score. These findings highlight the importance of addressing the issues of mobile phone use for suicide prevention among Chinese adolescents.