Insomnia symptoms as a mediator between school connectedness and suicidal ideation in Chinese adolescents: A three-wave longitudinal model.

Aim: School connectedness is related to suicidal ideation (SI) in adolescents. However, little is known about the mediating role of insomnia symptoms in the school connectedness-SI link. This study aimed to examine the longitudinal mediating effect of insomnia symptoms on the relationship between school connectedness and SI as well as the moderating effect of sex using a three-wave longitudinal design.

Methods: A total of 3110 adolescents completed three online surveys. Data were collected over the course of 1 year, in three waves 6 months apart. Participants completed the School Connectedness Scale, Youth Self-Rating Insomnia Scale, Self-rating Idea of Suicide Scale, Beck Depression Inventory and a self-compiled demographic questionnaire. Linear regressions and mediation analyses were performed to examine the associations between school connectedness, insomnia symptoms and SI.

Results: School connectedness had a significant mediating effect on SI through insomnia symptoms (β _a×b = -.03, 95% confidence interval = -0.04, -0.02) after controlling for demographics and depressive symptoms. Mediation analyses showed that insomnia symptoms accounted for 23.1% of the total effects in the entire sample, with 13.3% in males and 27.3% in females. Sex had no significant moderating effect on the school connectedness-SI link association.

Conclusions: The association between school connectedness and SI appears to be mediated by insomnia symptoms. Assessing and promoting school connectedness, as well as intervening and treating distress associated with insomnia, may have important clinical implications for reducing the risk of SI in adolescents.