Psychotic symptoms and neurocognition among patients with major depressive disorder: A chained mediation model of depressive symptoms and socio-occupational functioning

Abstract

BackgroundDepressive symptom and psychotic symptom have been identified as risk factors for impaired socio-occupational functioning in patients with major depressive disorder (MDD), while neurocognitive functioning is considered to be a potential protective factor against socio-occupational functioning. Nevertheless, little is known about the complex relationship among these factors in patients with MDD. The purpose of this research was to explore whether the relationship between depressive symptom severity and social-occupational functioning is mediated by neurocognitive functioning and psychotic symptom severity in MDD patients. MethodsA total of 659 eligible MDD patients included male and female, and their depressive symptoms and psychotic symptoms at baseline were assessed by the 17-item Hamilton Depression Scale (HAMD-17) and The Brief Psychiatric Rating Scale (BPRS) respectively. Cognitive domains were assessed by the MATRICS Consensus Cognitive Battery (MCCB), and subjective and objective functioning were measured by the Global Assessment of Functioning (GAF). LimitationThe analysis is cross-sectional, which limits causal inference. Result(1) The correlation between depressive symptoms and thought disturbance was positive (r = 0.125, p = 0.001), whereas the correlations with visual learning and memory (r = −0.146, p < 0.001) and socio-occupational functioning (r = −0.175, p < 0.001) were negative. (2) Depressive symptoms mainly affect the socio-occupational functioning of MDD patients via three indirect effects: the single mediating effect of psychotic symptoms and neurocognitive functioning, and the chain mediating effect of psychotic symptoms and neurocognitive functioning. ConclusionsThe results suggest that the relationship between depressive symptom severity and socio-occupational functioning in MDD patients is partially mediated by psychotic symptom severity and neurocognitive functioning.