Abstract
BACKGROUND: The psychological structural model of major depressive disorder (MDD) is complex and multifaceted, consisting of the environment factors (EF), cognitive function (CF), and behavioral-emotional manifestations (BEM). Currently, the diagnosis and treatment of MDD is difficult to improve the disease state as a whole through an intervention point. Constructing the psychological structural model of MDD and finding the critical node of the psychological structural model are meaningful for the diagnosis and treatment of MDD. METHODS: 308 MDD patients (MDDs) participated in this research. They completed assessments of 34 psychological factors, including EF, CF, BEM and interoception function (IF). Pearson correlation was used to investigate the relationship between IF and each factor in the depressive multidimensional psychological structural model (EF, CF and BEM) which was constructed by structural equation modeling (SEM). Critical nodes were identified by the goodness of fit of the model. The depressive multidimensional psychological structural model (EF, CF and BEM) was created through SEM. IF was added to the depressive multidimensional psychological structural model to further verify the pathways and effects of interoception in the network. RESULTS: IF was significantly correlated with all psychological factors. In the depressive multidimensional psychological structural model, EF (β(direct) = 0.163, p = 0.033) and BEM (β(direct) = 0.230, p = 0.003) can directly influence MDD. When adding IF to the model, interoception predicted all the factors in the model. The poorer EF led to the lower IF (β(direct) = - 0.346, p < 0.001). Interoception dysfunction increased the risk of the CF (β(direct) = -0.525, p = 0.002) and BEM (β(direct) = - 0.250, p = 0.031) of the patients. EF had the largest total effect on MDD (β(direct) = 0.365, β(indirect) = 0.150, β(total) = 0.515), IF (β(direct) = - 0.309, β(indirect) = - 0.126, β(total) = - 0.434) are second only to EF. CONCLUSIONS: IF is a part of the psychological structural model of MDD that predicts EF, CF, and BEM. It could be a potential intervention point to improve the depressive state as a whole.