ObjectiveTo explore the relationship between negative life events and depression severity in adolescent patients with depressive disorder， as well as the chain mediating role of insomnia symptoms and quality of life. Methods374 outpatient patients and hospitalized patients with adolescent depressive disorders were enrolled. The Adolescent Life Event Scale （ASLEC）， the Insomnia Severity Index （ISI）， the World Health Organization Quality of Life Questionnaire Short Form （WHOQOL-BREF）， and the Center for Epidemiology Depression Scale （CES-D） were used to evaluate the negative life event situation， insomnia symptoms， quality of life level and depression severity of the subjects， respectively. In addition， the PROCESS 4.0 macroprogram was used to analyze the chain mediating effect of insomnia symptoms and quality of life between negative life events and depression severity in patients with adolescent depressive disorder. ResultsThe results of correlation analysis showed that there was a significant correlation between negative life events and insomnia symptoms， quality of life， and depression severity （all P<0.05）. In addition， the results of chain mediation showed that negative life events had a significant direct effect on depression severity， with an effect size of 0.12 （P<0.001）. Insomnia symptoms and quality of life played a mediating role in the relationship between negative life events and depression severity in patients with adolescent depressive disorders， with indirect effect sizes of 0.062 （95%CI： 0.040-0.087） and 0.091 （95%CI： 0.059-0.123）， respectively. It could also play a chain mediation role， and the effect size was 0.039 （95%CI： 0.024-0.057）. ConclusionNegative life events experienced by patients with adolescent depressive disorder not only directly affect the severity of depressive symptoms， but may also indirectly exacerbate depression through insomnia symptoms and quality of life.

Objective: Excessive daytime sleepiness (EDS) and insomnia symptoms are common in patients with major depressive disorder (MDD), which might lead to a poor prognosis and an increased risk of depression relapse. The current study aimed to investigate the prevalence, and sociodemographic and clinical correlates of EDS and insomnia symptoms among adolescents with MDD. Methods: The sample of this cross-sectional study included 297 adolescents (mean age=15.26 years; range=12–18 years; 218 females) with MDD recruited from three general and four psychiatric hospitals in five cities (Hefei, Bengbu, Fuyang, Suzhou, and Ma’anshan) in Anhui Province, China between January and August, 2021. EDS and insomnia symptoms, and clinical severity of depressive symptoms were assessed using Epworth sleepiness scale, Insomnia Severity Index, and Clinical Global Impression-Severity. Results: The prevalence of EDS and insomnia symptoms in adolescents with MDD was 39.7% and 38.0%, respectively. Binary logistic regression analyses showed that EDS symptoms were significantly associated with higher body mass index (odds ratio [OR]=1.097, 95% confidence interval [CI]=1.027–1.172), more severe depressive symptoms (OR=1.313, 95% CI=1.028–1.679), and selective serotonin reuptake inhibitors use (OR=2.078, 95% CI=1.199–3.601). And insomnia symptoms were positively associated with female sex (OR=1.955, 95% CI=1.052–3.633), suicide attempts (OR=1.765, 95% CI=1.037–3.005), more severe depressive symptoms (OR=2.031, 95% CI=1.523–2.709), and negatively associated with antipsychotics use (OR=0.433, 95% CI=0.196–0.952). Conclusion EDS and insomnia symptoms are common among adolescents with MDD. Considering their negative effects on the clinical prognosis, regular screening and clinical managements should be developed for this patient population.