Mental Health Center, West China Hospital of Sichuan University, Chengdu 610041, China.
Department of Radiology and Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, West China Hospital, Sichuan University, Chengdu 610041, China; West China Medical Publishers, West China Hospital, Sichuan University, Chengdu 610041, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu 610041, China.
Behav Brain Res. 2025 Feb 26;478:115323. doi: 10.1016/j.bbr.2024.115323. Epub 2024 Nov 5.
Diffusion tensor imaging along perivascular spaces (DTI-ALPS) is an index that may provide insights into intracranial waste clearance processes. Glymphatic system dysfunction has been suggested to play a role in the development of major depressive disorder (MDD). Additionally, fatigue-a common precursor of MDD-is also closely connected to the waste clearance function of the central nervous system (CNS), further underscoring the significance of efficient waste removal in MDD. However, evidence linking altered DTI-ALPS index to MDD remains limited. This study aims to investigate the changes in the DTI-ALPS index in patients with MDD and explore the potential interplay between DTI-ALPS index alterations, fatigue, and the presence of MDD.
A total of 46 patients with MDD and 55 healthy controls (HC) were included in the study. All participants underwent diffusion tensor imaging using the same 3-T MRI (3-Tesla Magnetic Resonance Imaging) scanner. The DTI-ALPS index was assessed, and the Chalder Fatigue Scale (CFS) was used to evaluate fatigue levels in both groups, and the 17-item Hamilton Depression Rating Scale (HAMD-17) was used to evaluate the severity of depression in the patients. We compared the DTI-ALPS index and clinical characteristics between the MDD and HC group, and explored the relationship among the DTI-ALPS index, CFS scores, and the presence of MDD through mediation analysis.
The DTI-ALPS index in the right hemisphere (DTI-ALPS-R) is significantly lower in patients with MDD (t = 2.41, P = 0.02). The MDD patients exhibited significantly higher scores on the CFS scales compared with HCs (t = 13.12, P <.001). Mediation analysis showed that the CFS score plays a significant mediating role between DTI-ALPS-R and the presence of MDD, acting as a full mediator (indirect effect β = -0.230, 95 % CI: [-0.388, -0.059]).
Our study found that patients with MDD have a reduced DTI-ALPS index. This reduction appears to contribute to the development of MDD by facilitating the accumulation of fatigue symptoms. These findings may provide a new perspective on the pathogenesis of MDD, suggest a potential new biomarker for MDD, and offer new insights for its treatment.
沿血管周围空间的弥散张量成像（DTI-ALPS）是一个可能提供颅内废物清除过程见解的指标。 已经提出，神经胶细胞系统功能障碍在重度抑郁症（MDD）的发展中起作用。 此外，疲劳 - MDD 的常见前兆 - 也与中枢神经系统（CNS）的废物清除功能密切相关，这进一步强调了在 MDD 中有效清除废物的重要性。 然而，将改变的 DTI-ALPS 指数与 MDD 联系起来的证据仍然有限。 本研究旨在调查 MDD 患者的 DTI-ALPS 指数变化，并探讨 DTI-ALPS 指数改变、疲劳与 MDD 之间存在的潜在相互作用。
共有 46 名 MDD 患者和 55 名健康对照者（HC）纳入本研究。 所有参与者均使用相同的 3T MRI（3 特斯拉磁共振成像）扫描仪进行弥散张量成像。 评估 DTI-ALPS 指数，并使用 Chalder 疲劳量表（CFS）评估两组的疲劳水平，使用 17 项汉密尔顿抑郁评定量表（HAMD-17）评估患者的抑郁严重程度。 我们比较了 MDD 和 HC 组之间的 DTI-ALPS 指数和临床特征，并通过中介分析探讨了 DTI-ALPS 指数、CFS 评分与 MDD 之间的关系。
MDD 患者的右侧半球 DTI-ALPS 指数（DTI-ALPS-R）明显降低（t = 2.41，P = 0.02）。 MDD 患者的 CFS 量表评分明显高于 HC（t = 13.12，P <.001）。 中介分析表明，CFS 评分在 DTI-ALPS-R 与 MDD 之间起着显著的中介作用，是完全中介（间接效应β= -0.230，95%CI：[-0.388，-0.059]）。
我们的研究发现，MDD 患者的 DTI-ALPS 指数降低。 这种减少似乎通过促进疲劳症状的积累来促进 MDD 的发展。 这些发现可能为 MDD 的发病机制提供新的视角，提示 MDD 的潜在新生物标志物，并为其治疗提供新的见解。
