Correlation between White Matter Changes and Clinical Symptoms in Patients with Major Depressive Disorder

To analyse the structural characteristics and fibre integrity of white matter in patients with major depressive disorder (MDD) and its relationship with depressive symptoms. Patients with MDD admitted to Wenzhou Seventh People' Hospital between September 2021 and May 2023 were recruited as participants in the experimental group, and healthy volunteers matching in gender, age and years of education were recruited during the same period as the control group. The two groups were compared in terms of fractional anisotropy (FA), mean diffusivity (MD) and axial diffusivity (AD). The relationship between the white matter volume and the values of FA, MD and AD in different brain regions and the severity of depressive symptoms in the experimental group was analysed. Fifty-eight patients were included in the experimental group, and 60 healthy controls in the control group. In the experimental group, the white matter volume of the right inferior frontal gyrus was negatively correlated with the Hamilton depression rating scale (HAMD-17) score (r = -0.355, P < 0.05), and the left parietal gyrus was negatively correlated with the HAMD-17 score (r = -0.361, P < 0.05). The FA value in the occipital radiations of the corpus callosum of the white matter was negatively correlated with the HAMD-17 score (r = -0.410, P < 0.05). Moreover, the MD value of the left and right anterior thalamic radiation of white matter was negatively correlated with the HAMD-17 score (r = -0.389, P < 0.05; r = -0.489, P < 0.01, respectively), and the AD value showed a negative correlation with the HAMD-17 score (r = -0.446, -0.405, respectively, both P < 0.05). Patients with MDD suffer from decreased white matter volume and impaired fibre integrity of white matter, including in the parietal lobe, corpus callosum, corticospinal tract and inferior longitudinal tract. Abnormalities in white matter structure and fibre integrity have a close bearing on the severity of MDD.