Negative life events and suicidality among adolescents in Western China: the mediating effect of depressive symptoms and the moderating effect of self-esteem.

Objective: To investigate the mediating role of depressive symptoms in the relationship between negative life events (NLEs) and suicidality, as well as to test the moderating effect of self-esteem in the mediation model.

Methods: A total of 3,003 adolescents from Han, Tibetan, and Yi ethnic groups living in Western China were included in this study. Utilizing the structural equation model, a mediation model and a moderated mediation model were constructed.

Results: The presence of NLEs was positively associated with suicidality (β = 0.17, p < 0.001). Depressive symptoms partially mediated the relationship between NLEs and suicidality (indirect effect β = 0.19, p < 0.001). Self-esteem moderated both the antecedent and subsequent segments of the mediating paths of "NLEs → depressive symptoms → suicidality" and the direct relationship between NLEs and suicidality. Among adolescents with a low level of self-esteem, the mediating effect coefficient of depressive symptoms was higher at 0.18 (95% confidence interval (CI): 0.14-0.23), in contrast to adolescents with a high level of self-esteem, where the mediating effect coefficient of depressive symptoms was 0.04 (95% CI: 0.02-0.07).

Conclusion: NLEs are directly associated with an increased risk of suicidality and indirectly related to suicidality by increasing the risk of depressive symptoms among adolescents. Self-esteem can moderate the mediating effect of depressive symptoms and the relationship between NLEs and suicidality. The intervention strategy for preventing suicidality among adolescents who have experienced NLEs should focus on reducing depressive symptoms and improving self-esteem.