The relationship between sleep quality and suicidal ideation in college students: the longitudinal mediating role of negative affect and the neural basis of this relationship

Studies have shown that sleep quality is a critical predictor of suicidal ideation. However, the mechanisms by which sleep quality affects suicidal ideation remain largely unknown. We aimed to examine the longitudinal relationship between sleep quality and suicidal ideation among Chinese college students and the mediating role of negative affect (Study 1). We also aimed to identify the neural basis of the association between sleep quality and suicidal ideation (Study 2).

In Study 1, a total of 324 college students (19% males; M_age = 18.50 years, SD = 0.81) completed questionnaires at two time points, separated by 1 month. In Study 2, the amplitude of low-frequency fluctuations (ALFF) was used to examine the neural basis of the relationship between sleep quality and suicidal ideation among 70 college students.

Poor sleep quality predicted increases in suicidal ideation (whether it’s total, active, or passive suicidal ideation) 1 month later in college students and exacerbated suicidal ideation by increasing negative affect. Furthermore, according to the results of resting-state fMRI, college students’ total suicidal ideation was positively associated with the ALFF in the triangular part of the left inferior frontal gyrus and negatively associated with the ALFF in the left paracentral lobule. Passive suicidal ideation was positively associated with the ALFF in the left medial orbital superior frontal gyrus, left middle cingulum gyrus, and left middle frontal gyrus. More importantly, the ALFF of the triangular part of the left inferior frontal gyrus mediated the association between sleep quality and total suicidal ideation, while the ALFF in the left middle frontal gyrus mediated the association between sleep quality and passive suicidal ideation.

These results suggest that poor sleep quality is a short-term risk factor for suicidal ideation in college students. Sleep quality may influence suicidal ideation through psychological and neurobiological pathways.