Childhood Adversity and Adolescent Smartphone Use Across Sexual Orientation and Gender Expression.

Importance: Nonheterosexual and gender-nonconforming (GNC) individuals tend to report adverse childhood experiences (ACEs) more frequently compared with heterosexual and gender-conforming individuals, and individuals who have experienced ACEs, identify as nonheterosexual, or exhibit moderate to high levels of GNC are more prone to engaging in problematic smartphone use (PSU). However, there is limited school-based data among adolescents regarding this matter. Objectives: To explore the associations between ACEs and PSU among adolescents across different sexual orientation and gender expression groups. Design, setting, and participants: Using data from the 2021 School-Based Chinese Adolescents Health Survey, this cross-sectional study includes participants from 288 public high schools across 8 provinces in China. Statistical analysis was performed from October 2023 to February 2024. Exposures: Data on ACEs, sexual orientations, and gender expressions (high, moderate, and low GNC) were collected. Main outcomes and measures: PSU was assessed using the 10-item Smartphone Addiction Scale-Short Version (SAS-SV). Weighted linear, logistic, or Poisson regression models were used. Results: Among the 85 064 adolescents included (mean [SD] age, 14.92 [1.77] years), 42 632 (50.1%) were female, 70 157 (83.2%) identified as Han Chinese, and 14 208 (16.8) identified as other ethnicities (Miao, Hui, Yi, Dai, and other ethnic groups). The prevalence of PSU among participants was 35.4%. Weighted Poisson regression models indicated that the interaction between GNC and ACE was significant (adjusted prevalence ratio [APR], 0.98; 95% CI, 0.97-0.99). Further stratified analysis demonstrated homosexual adolescents who experienced 4 or more ACEs showed a significantly increased prevalence of PSU (APR, 1.79; 95% CI, 1.64-1.96). Similarly, a markedly higher prevalence of PSU was observed among bisexual individuals with 4 or more ACEs (APR, 1.60; 95% CI, 1.41-1.80). Regarding gender expression categories, a significantly higher prevalence of PSU was noted among high GNC adolescents with 4 or more ACEs (APR, 1.78; 95% CI, 1.60-1.98) compared with low GNC adolescents without ACEs. Furthermore, experiencing any 3 ACE categories (abuse, neglect, and household dysfunction) was associated with an increased prevalence of PSU across different sexual orientation and gender expression subgroups. Conclusions and relevance: In this cross-sectional study, the amalgamation of elevated ACE scores with nonheterosexual orientations or GNC identities was significantly associated with increased PSU prevalence. These findings underscore that preventing ACEs may be beneficial in mitigating PSU among adolescents, particularly for nonheterosexual adolescents and those with high levels of GNC.