Insomnia symptoms, depressive symptoms, and suicide ideation in Japanese white-collar employees

Although poor sleep quality is the most common subjective complaint of workers and is a risk factor for depressive symptoms and suicide, researchers have not yet provided definitive links between insomnia symptoms, depressive symptoms, and suicide.

In our mediation model, we hypothesized relationships among insomnia symptoms, depressive symptoms, and suicide ideation. The purpose here was to use structural equation modeling (SEM) to test our mediation model.

Three hundred forty-three Japanese full-time white-collar workers completed the measures to assess insomnia symptoms, depressive symptoms, and suicide ideation over an approximately 3-month period.

A SEM analysis revealed that insomnia symptoms were positively and significantly associated with depressive symptoms, and depressive symptoms were positively and significantly associated with suicide ideation. Two tests showed a significant indirect effect of insomnia symptoms on suicide ideation through depressive symptoms. Thus, these results supported our mediation model.

We conclude that insomnia symptoms were positively associated with suicidal ideation, though this relation was accounted for by depressive symptoms in Japanese white-collar workers.