Sex-specific networks of depressive symptoms and cognitive deficits in major depressive disorder: A network analysis approach

Background

Major depressive disorder (MDD) represents a prevalent mental health condition characterized by profound cognitive and emotional disturbances. Emerging evidence suggests sex differences in how these symptoms interact with cognitive deficits, yet the mechanisms remain unclear. Traditional methods have limitations in capturing these complex interactions. This research employs network analysis to investigate and contrast the interrelationships between depressive symptoms and cognitive functions in male and female individuals diagnosed with MDD, offering new insights into sex-specific patterns within the disorder.

Methods

A cohort of 375 inpatients diagnosed with MDD, comprising 148 males and 227 females, was recruited for the study. Clinical evaluations encompassed the 24-item Hamilton Depression Rating Scale (HDRS-24) and an extensive array of neurocognitive assessments targeting domains such as attention, memory, processing speed, and executive function. Gaussian graphical models (GGMs) were employed to construct networks of depressive symptoms and cognitive functions, focusing on identifying central and bridge symptoms within these networks.

Results

The network analysis revealed distinct patterns in the interaction of depressive symptoms and cognitive functions between males and females. In males, sleep disturbance and processing speed emerged as central features, while in females, psychomotor retardation, working memory, and processing speed were more prominent. Sleep disturbance was identified as the key bridge symptom in males, whereas psychomotor retardation and working memory served as bridge symptoms in females. Despite these differences, no significant sex differences were found in global network strength or structure.

Conclusion

This study elucidated distinct patterns in the network relationships between depressive symptoms and cognitive functions among male and female patients diagnosed with MDD. These findings suggest that although the overall impact of MDD on cognitive function is consistent across sexes, the pathways through which these effects manifest differ. This underscores the need for tailored therapeutic strategies that target these sex-specific network features to optimize treatment outcomes in MDD patients.