Department of Psychiatry, University of Münster, Münster, Germany.
Neuropsychopharmacology. 2019 Apr;44(5):883-889. doi: 10.1038/s41386-018-0283-6. Epub 2018 Nov 27.
While research concerning brain structural biomarkers of major depressive disorder (MDD) is continuously progressing, our state of knowledge regarding biomarkers of specific clinical profiles of MDD is still limited. The aim of the present study was to investigate brain structural correlates of social anhedonia as a cardinal symptom of MDD. In a cross-sectional study, we investigated n = 166 patients with MDD and n = 166 matched healthy controls (HC) using structural magnetic resonance imaging (MRI). Social anhedonia was assessed using the Chapman Scales for Social Anhedonia (SAS). An anhedonia x group ANCOVA was performed in a region of interest approach of the dorsal and ventral striatum (bilateral caudate nucleus, putamen, nucleus accumbens respectively) as well as on whole-brain level. The analyses revealed a significant main effect for social anhedonia: higher SAS-scores were associated with reduced gray matter volume in the bilateral caudate nucleus in both the MDD-group (p = 0.002) and the HC-group (p = 0.032). The whole-brain analysis confirmed this association (left: p = 0.036, right: p = 0.047). There was no significant main effect of group and no significant anhedonia x group interaction effect. This is the first study providing evidence for volumetric aberrations in the reward system related to social anhedonia independently of diagnosis, depression severity, medication status, and former course of disease. These results support the hypothesis that social anhedonia has a brain biomarker serving as a possible endophenotype of depression and possibly providing an alternative approach for a more precise and effective treatment.
尽管有关重度抑郁症（MDD）的脑结构生物标志物的研究不断取得进展，但我们对 MDD 特定临床特征的生物标志物的了解仍然有限。本研究旨在探讨社会快感缺失作为 MDD 的主要症状的脑结构相关性。在一项横断面研究中，我们使用结构磁共振成像（MRI）对 n=166 例 MDD 患者和 n=166 例匹配的健康对照者（HC）进行了研究。使用 Chapman 社会快感缺失量表（SAS）评估社会快感缺失。在感兴趣的区域方法中对背侧和腹侧纹状体（双侧尾状核、壳核、伏隔核）以及全脑水平进行了快感缺失 x 组 ANOVA。分析显示，快感缺失存在显著的主效应：SAS 评分越高，双侧尾状核的灰质体积越小，在 MDD 组（p=0.002）和 HC 组（p=0.032）中均如此。全脑分析证实了这一关联（左：p=0.036，右：p=0.047）。组间没有显著的主效应，也没有快感缺失 x 组的交互效应。这是第一项提供证据表明，与社会快感缺失相关的奖励系统存在体积异常，而与诊断、抑郁严重程度、用药情况和既往病程无关。这些结果支持了这样一种假说，即社会快感缺失有一个脑生物标志物，可作为抑郁的一个可能的内表型，并可能为更精确和有效的治疗提供一种替代方法。
