Chronotype and depressive symptoms in healthy subjects: the mediating role of hopelessness and subjective sleep quality.

Chronotype preference and lower sleep quality in university students can influence mental health. Individuals with evening chronotypes have a high risk of mental health problems, including depressive symptoms. However, the underlying mechanisms are still under investigation. Hopelessness is composed of negative feelings and thoughts about the future and is closely related to depressive symptomatology. The aim of the study was to determine whether reduced sleep quality and hopelessness mediate the association between chronotype and depressive symptoms in a student sample, which was evaluated cross-sectionally. A total of 339 Turkish students (53.7% female, mean age 22.18 ± 1.79 y) completed the Morningness-Eveningness Questionnaire, the Pittsburgh Sleep Quality Index, the Beck Hopelessness Scale, and the Beck Depression Inventory. Mediation analysis showed no significant direct relationship between eveningness and depressive symptoms. The relationship between eveningness and depressive symptoms was mediated by hopelessness, but not by subjective sleep quality (effect = - 0.03, SE: 0.01, CI: -0.04, -0.02). Better knowledge of the relationship between hopelessness and eveningness might form the basis of a more specific approach to the prevention of depression in evening types.