Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha 410011.
National Clinical Research Center for Mental Disorders, Second Xiangya Hospital, Changsha 410011.
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2022 Mar 28;47(3):289-300. doi: 10.11817/j.issn.1672-7347.2022.210743.
Major depressive disorder (MDD) patients with anhedonia tend to have a poor prognosis. The underlying imaging basis for anhedonia in MDD remains largely unknown. The relationship between nodal properties and anhedonia in MDD patients need to be further investigated. Herein, this study aims to explore differences of cerebral functional node characteristics in MDD patients with severe anhedonia (MDD-SA) and MDD patients with mild anhedonia (MDD-MA) before and after the antidepressant treatment.
Ninety participants with current MDD were recruited in this study. 24-Item Hamilton Depression Scale (HAMD-24) and Snaith-Hamilton Pleasure Scale (SHAPS) were used to assess the severity of depression and anhedonia at baseline and the end of 6-months treatment. The MDD patients who scored above the 25th percentile on the SHAPS were assigned to an MDD-SA group (19), while those who scored below the 25th percentile were assigned to an MDD-MA group (18). All patients in the 2 groups received antidepressant treatment. Functional magnetic resonance imaging (fMRI) images of all the patients were collected at baseline and the end of 6-months treatment. Graph theory was applied to analyze the patients' cerebral functional nodal characteristics, which were measured by efficiency (e) and degree (k).
Repeated measures 2-factor ANCOVA showed significant main effects on group on the e and k values of left superior frontal gyrus (LSFG) (0.003 and 0.008, respectively), and on the e and k values of left medial orbital-frontal gyrus (LMOFG) (=0.004 and 0.008, respectively). Compared with the MDD-MA group, the significantly higher e and k values of the LSFG (0.015 and 0.021, respectively), and the significantly higher e and k values of the LMOFG (=0.015 and 0.037, respectively) were observed in the MDD-SA group at baseline. Meanwhile, higher SHAPS scores could result in higher e and k values of LSFG (=0.019 and 0.026, respectively), and higher e value of LMOFG (0.040) at baseline; higher SHAPS scores could result in higher e values of LSFG (0.049) at the end of 6-months treatment. The multiple linear regression analysis revealed that sex were negatively correlated with the e and k values of LSFG (= -0.014, =0.004; =-1.153, =0.001, respectively). The onset age of MDD was negatively correlated with the k value of LSFG (=-0.420, =0.034) at the end of 6-months treatment. We also found that SHAPS scores at baseline were positively correlated with the HAMD-24 scores (=0.387, =0.022) at the end of 6-months treatment.
There are obvious differences in nodal properties between the MDD-SA and the MDD-MA patients, such as the high e of LSFG in the MDD-SA patients, which may be associated with the severity of anhedonia. These nodal properties could be potential biomarkers for the prognosis of MDD. The increased e and k values in the LSFG of MDD-SA patients may underlie a compensatory mechanism or protective mechanism. The mechanism may be an important component of the pathological mechanism of MDD-SA. The poor prognosis in the MDD-SA patients suggests that anhedonia may predict a worse prognosis in MDD patients. Sex and onset age of MDD may affect the nodal properties of LSFG at baseline and the end of 6-months treatment.
有快感缺失的重性抑郁障碍（MDD）患者往往预后较差。MDD 快感缺失的潜在影像学基础在很大程度上尚不清楚。MDD 患者的节点属性与快感缺失之间的关系需要进一步研究。本研究旨在探讨重度快感缺失（MDD-SA）和轻度快感缺失（MDD-MA）的 MDD 患者在抗抑郁治疗前后大脑功能节点特征的差异。
本研究共纳入 90 名当前患有 MDD 的参与者。使用 24 项汉密尔顿抑郁量表（HAMD-24）和 Snaith-Hamilton 快感量表（SHAPS）在基线和 6 个月治疗结束时评估抑郁和快感缺失的严重程度。SHAPS 评分高于第 25 百分位的 MDD 患者被分配到 MDD-SA 组（19 人），而 SHAPS 评分低于第 25 百分位的患者被分配到 MDD-MA 组（18 人）。所有 2 组患者均接受抗抑郁治疗。在基线和 6 个月治疗结束时收集所有患者的功能磁共振成像（fMRI）图像。应用图论分析患者的大脑功能节点特征，通过效率（e）和度（k）来衡量。
重复测量 2 因素方差分析显示，组间在左侧额上回（LSFG）的 e 和 k 值（分别为 0.003 和 0.008）和左侧眶额内侧回（LMOFG）的 e 和 k 值（分别为 0.004 和 0.008）上有显著的主效应。与 MDD-MA 组相比，MDD-SA 组的 LSFG 的 e 和 k 值（分别为 0.015 和 0.021）和 LMOFG 的 e 和 k 值（分别为 0.015 和 0.037）显著更高。同时，较高的 SHAPS 评分与基线时 LSFG 的 e 和 k 值（分别为 0.019 和 0.026）和 LMOFG 的 e 值（0.040）较高有关；治疗 6 个月结束时，较高的 SHAPS 评分与 LSFG 的 e 值（0.049）较高有关。多元线性回归分析显示，性别与 LSFG 的 e 和 k 值呈负相关（= -0.014，=0.004；= -1.153，=0.001）。MDD 的发病年龄与 LSFG 的 k 值在治疗 6 个月结束时呈负相关（=-0.420，=0.034）。我们还发现，基线时的 SHAPS 评分与治疗 6 个月结束时的 HAMD-24 评分呈正相关（=0.387，=0.022）。
MDD-SA 和 MDD-MA 患者之间存在明显的节点属性差异，例如 MDD-SA 患者 LSFG 的高 e 值，这可能与快感缺失的严重程度有关。这些节点属性可能是 MDD 预后的潜在生物标志物。LSFG 中 MDD-SA 患者的 e 和 k 值增加可能是代偿或保护机制的基础。该机制可能是 MDD-SA 的病理机制的重要组成部分。MDD-SA 患者的预后较差表明，快感缺失可能预示着 MDD 患者的预后较差。性别和 MDD 的发病年龄可能会影响 LSFG 在基线和治疗 6 个月结束时的节点属性。
