The relationship between sleep quality and depression: Critical roles of reflective and brooding rumination and sleep-related cognition.

There is a complex interplay between sleep problems and depression. This study explored the possible effects of rumination and dysfunctional beliefs about sleep on the relationship between sleep quality and depression. A cross-sectional survey of 1240 Chinese adults was conducted to assess the possible relationships. The results showed a chain mediating effect of reflection rumination and brooding rumination on the relationship between sleep quality and depression, accounting for 38.91% of the total variance. A moderating role of unreasonable attitudes about sleep was also discovered among the study participants, which enhanced the relationship between reflection and brooding, leading to a further increase in this relationship. Individually-tailored approaches targeting rumination and cognition may more effectively alleviate depression or co-morbid sleep problems and depression than the current standards of care.