Wenqiong Zhang,1,* Nan Zhou,1,* Jie Li2 

1Department of Mood Disorders, Tianjin Anding Hospital, Tianjin City, 300222, People’s Republic of China; 2The Dean’s Office, Tianjin Anding Hospital, Tianjin City, 300222, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Jie Li, The Dean’s Office, Tianjin Anding Hospital, No. 13, Liulin Road, Hexi District, Tianjin City, 300222, People’s Republic of China, Tel +86-022-88188326, Email jielimd859@163.com

Background: Sleep disorder is closely related to depressive and anxious status as well as cognitive symptoms.
Materials and Methods: A total of 173 cases with the first-episode major depressive disorder (MDD) were involved in this study. The Hamilton Depression Scale (HAMD-17), Hamilton Anxiety Scale (HAMA), Pittsburgh Sleep Quality Index (PSQI), and Repeatable battery for the Assessment of Neuropsychological Status (RBANS) were used to assess the patients. Three visits were set at baseline at the 4th and the 8th weeks. Latent Growth Curve Models (LGCM) were used to analyze the changing tendency and correlation between sleep disorder, depression, anxiety status, and cognitive function in patients with MDD.
Results: Baseline sleep status in patients with MDD could predict cognitive function (p=0.043) and changes in cognitive function (p=0.016), and changes in depressive symptoms could negatively predict cognitive function (p=0.021). Changes in depressive status negatively predictability of its cognitive function (p=0.005). Changes in sleep status negatively predict cognitive function (p=0.099). Sex, age, educational duration, and nature of work were included in the LGCM. The comparison among the subgroups in the LGCM indicated that these four dimensions showed consistency in dynamic tendency, demonstrating that cognitive function changes with sleep status.
Conclusion: The more severe the sleep disorder in patients with first-episode MDD, the more obvious was the damage to cognition. The dynamic impact of sleep quality on cognitive function is positively correlated, and over time, there is an association between the remission speed of depressive or anxiety symptoms and improving the speed of cognitive function in patients with MDD.

Keywords: major depressive disorder, sleep disorder, cognitive function, dynamic tracking, correlation, Latent Growth Curve Model