Emotion and Development Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland.
The Catholic University of America, Washington, DC.
J Am Acad Child Adolesc Psychiatry. 2020 Oct;59(10):1135-1145. doi: 10.1016/j.jaac.2019.05.035. Epub 2019 Jul 19.
Disruptive mood dysregulation disorder (DMDD) codifies severe, chronic irritability. Youths with bipolar disorder (BD) also present with irritability, but with an episodic course. To date, it is not clear whether aberrant white matter microstructure-a well-replicated finding in BD-can be observed in DMDD and relates to symptoms of irritability.
We acquired diffusion tensor imaging data from 118 participants (BD = 36, DMDD = 44, healthy volunteers (HV = 38). Images of fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) were processed with tract-based spatial statistics controlling for age and sex. The data were also used to train Gaussian process classifiers to predict diagnostic group.
In BD vs DMDD, FA in the corticospinal tract was reduced. In DMDD vs HV, reductions in FA and AD were confined to the anterior corpus callosum. In BD vs HV, widespread reductions in FA and increased RD were observed. FA in the anterior corpus callosum and corticospinal tract was negatively associated with irritability. The Gaussian process classifier could not discriminate between BD and DMDD, but achieved 68% accuracy in predicting DMDD vs HV and 75% accuracy in predicting BD vs HV.
Aberrant white matter microstructure was associated with both categorical diagnosis and the dimension of irritability. Alterations in DMDD were regionally discrete and related to reduced AD. In BD, we observed widespread increases in RD, supporting the hypothesis of altered myelination in BD. These findings will contribute to the pathophysiological understanding of DMDD and its differentiation from BD.
Studies of Brain Function and Course of Illness in Pediatric Bipolar Disorder; https://clinicaltrials.gov/; NCT00025935; Child & Adolescent Bipolar Disorder Brain Imaging and Treatment Study; https://clinicaltrials.gov/; NCT00006177.
破坏性心境失调障碍 (DMDD) 编码严重、慢性易怒。双相情感障碍 (BD) 患者也表现出易怒，但具有发作性病程。迄今为止，尚不清楚异常的脑白质微观结构——BD 中得到充分复制的发现——是否可以在 DMDD 中观察到，并与易怒症状相关。
我们从 118 名参与者（BD=36，DMDD=44，健康志愿者（HV=38）中获得了弥散张量成像数据。使用基于束的空间统计学，控制年龄和性别，对分数各向异性（FA）、轴向弥散度（AD）和径向弥散度（RD）图像进行处理。还使用数据来训练高斯过程分类器以预测诊断组。
在 BD 与 DMDD 中，皮质脊髓束的 FA 降低。在 DMDD 与 HV 中，FA 和 AD 的降低仅限于前胼胝体。在 BD 与 HV 中，观察到广泛的 FA 降低和 RD 增加。前胼胝体和皮质脊髓束的 FA 与易怒呈负相关。高斯过程分类器无法区分 BD 和 DMDD，但在预测 DMDD 与 HV 之间的准确率为 68%，在预测 BD 与 HV 之间的准确率为 75%。
异常的脑白质微观结构与分类诊断和易怒维度有关。DMDD 的改变是局部离散的，与 AD 降低有关。在 BD 中，我们观察到 RD 广泛增加，支持 BD 中髓鞘改变的假说。这些发现将有助于 DMDD 的病理生理学理解及其与 BD 的区分。
儿科双相情感障碍的大脑功能和疾病进程研究；https://clinicaltrials.gov/；NCT00025935；儿童和青少年双相情感障碍脑成像和治疗研究；https://clinicaltrials.gov/；NCT00006177。
