Pathways linking loneliness and depressive symptoms among Chinese adolescents: The mediating role of sleep disturbance.

Background: Despite growing evidence linking loneliness and depressive symptoms, the underlying pathways remain unclear. This study aims to assess the impact of loneliness on depressive symptoms among Chinese adolescents and investigate the potential mediating role of sleep disturbance.

Methods: A cross-sectional study was conducted between November and December 2021. Loneliness, depressive symptoms, and sleep disturbance were assessed using the UCLA Loneliness Scale, the 9-item Patient Health Questionnaire, and the Pittsburgh Sleep Quality Index questionnaire, respectively. Baron and Kenny's causal steps method and the Karlson-Holm-Breen method were applied to explore the mediating role of sleep disturbance. Subgroup analysis by gender was also conducted.

Results: A total of 6838 adolescents were included, with 52.2 % boys and a mean age of 14.5 (SD = 1.6) years. Approximately 15.8 % of the adolescents reported depressive symptoms. Loneliness was positively associated with depressive symptoms after controlling for covariates (OR = 1.34, 95%CI = 1.31-1.36). After incorporating sleep disturbance into the model, the association was still significant (OR = 1.28, 95%CI = 1.25-1.31). Sleep disturbance partially mediated this association, contributing to 18.89 % of the total effects. The associations and mediation effects were consistent across both genders, with no moderating effect of gender observed.

Limitations: The cross-sectional design limits the ability to establish causality.

Conclusion: Loneliness was significantly associated with depressive symptoms in Chinese adolescents and this association was partially mediated by sleep disturbance. Interventions aimed at reducing loneliness and improving sleep quality may help lower the risk of depressive symptoms in Chinese adolescents, regardless of genders. Nevertheless, further randomized controlled trials are needed to confirm these findings.