Zhang Tianhao, Zhao Bingcong, Shi Chuan, Nie Binbin, Liu Hua, Yang Xinjing, Sun Yang, Li Panlong, Lin Lei, Yang Xiuyan, Li Jing, Gao Xingzhou, Feng Shixing, Li Xiang, Sun Xi, Pan Tingting, Feng Ting, Bao Tuya, Shan Baoci
Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China; School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing, China.
School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China; Acupuncture and Moxibustion Department, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China.
J Affect Disord. 2020 Apr 1;266:243-251. doi: 10.1016/j.jad.2020.01.135. Epub 2020 Jan 27.
Subthreshold depression (StD) is a prevalent condition that may increase the risk of incident major depressive disorder (MDD). However, the relationship between StD and MDD remains unclear.
A total of 153 adult subjects, including 53 drug-naive MDD, 50 StD and 50 healthy control (HC) subjects, underwent a T1-weighted magnetic resonance imaging scan, and the gray matter volume (GMV) alterations among the three groups were quantitatively analyzed using voxel-based morphometry (VBM). Then, to capture the whole-brain connectivity characteristics, we constructed morphological brain networks (MBN) based on the similarity among brain regions of individual VBM images and compared the network connection strengths among the three groups.
The StD and MDD subjects had similar patterns of GMV reductions in the orbitofrontal cortex and left temporal gyrus, although the magnitude of the reductions was smaller in StD subjects. Moreover, a total of 21 morphological connections were significantly different among the three groups. For the majority of the different connections (15/21), the connection strength of the StD group took an intermediate position between that of the MDD and HC groups.
There is still a lack of a consistent definition of StD, and the age range of the subjects in this study was wide. Meanwhile the mechanisms and biological significance of the MBN remains to be clarified.
These results may support the hypothesis that depression is better expressed as a spectrum and that StD exists on a spectrum with MDD.
阈下抑郁（StD）是一种常见病症，可能会增加发生重度抑郁症（MDD）的风险。然而，StD与MDD之间的关系仍不明确。
共有153名成年受试者，包括53名未服用过药物的MDD患者、50名StD患者和50名健康对照（HC）受试者，接受了T1加权磁共振成像扫描，并使用基于体素的形态学测量（VBM）对三组之间的灰质体积（GMV）变化进行了定量分析。然后，为了捕捉全脑连接特征，我们基于个体VBM图像脑区之间的相似性构建了形态学脑网络（MBN），并比较了三组之间的网络连接强度。
StD和MDD受试者在眶额皮质和左侧颞回有相似的GMV减少模式，尽管StD受试者的减少幅度较小。此外，三组之间共有21个形态学连接存在显著差异。对于大多数不同的连接（15/21），StD组的连接强度处于MDD组和HC组之间的中间位置。
目前仍缺乏对StD的一致定义，且本研究中受试者的年龄范围较广。同时，MBN的机制和生物学意义仍有待阐明。
这些结果可能支持以下假设，即抑郁症更好地表现为一种谱系，且StD与MDD存在于同一谱系中。
