Research Center of Brain and Cognitive Neuroscience, Liaoning Normal University, Dalian, China; Key Laboratory of Brain and Cognitive Neuroscience, Liaoning Province, Dalian, China.
Department of Physiology, Jiamusi University, Jiamusi, China.
Sleep Med. 2022 Jul;95:84-90. doi: 10.1016/j.sleep.2022.04.022. Epub 2022 Apr 30.
Depressive symptoms typically exhibit sex differences among medical students and are associated with bedtime procrastination (BP) and self-control. However, it remains unclear whether sex differences exist in the relationship between these variables.
A cross-sectional observational study was conducted among 402 medical students from a public university in China. Students' depressive symptoms, BP, and trait self-control were assessed using the Chinese version of the Beck Depression Inventory (BDI)-II, the Bedtime Procrastination Scale, and the Self-control Scale, respectively. Applying a BDI cutoff value of 14, 364 valid participants were divided into non-depressed (<14) and depressed (≥14) groups.
Binary logistic regression revealed that BP was an independent predictor of the prevalence of depressive symptoms in women only. Hierarchical regression showed that high BP levels were independently positively correlated to more depressive symptoms only in non-depressed women. In contrast, low self-control levels were independently negatively correlated to more depressive symptoms in non-depressed and depressed female students. Furthermore, structural equation modeling reflected the mediating role of BP between self-control and depressive symptoms in the non-depressed female group only.
Sex differences exist in the effect of BP on depressive symptoms as well as the relationship between self-control and depressive symptoms among Chinese medical students. As a moderator, sex regulates the mediating effect of BP on the relationship between self-control and depressive symptoms in the non-depressed group. These findings provide a sex-specific perspective for targeted prevention and intervention of depressive symptoms among high-risk medical students, especially during the non-depressed period.
抑郁症状在医学生中通常表现出性别差异,与就寝时间拖延(BP)和自我控制有关。然而,这些变量之间的关系是否存在性别差异尚不清楚。
对中国一所公立大学的 402 名医学生进行了横断面观察性研究。使用贝克抑郁量表第二版(BDI-II)、就寝时间拖延量表和自我控制量表分别评估学生的抑郁症状、BP 和特质自我控制。应用 BDI 截断值为 14,364 名有效参与者被分为非抑郁(<14)和抑郁(≥14)组。
二元逻辑回归显示,BP 是女性抑郁症状发生率的独立预测因子。分层回归显示,仅在非抑郁女性中,高 BP 水平与更多的抑郁症状呈独立正相关。相比之下,在非抑郁和抑郁的女性学生中,低自我控制水平与更多的抑郁症状呈独立负相关。此外,结构方程模型反映了 BP 在非抑郁女性组中自我控制与抑郁症状之间的中介作用。
BP 对抑郁症状的影响以及自我控制与抑郁症状之间的关系在医学生中存在性别差异。作为一个调节变量,性别调节了 BP 在非抑郁组中自我控制与抑郁症状之间关系的中介作用。这些发现为有针对性地预防和干预高危医学生的抑郁症状提供了一个性别特异性的视角,特别是在非抑郁期间。