Department of Psychiatry, Washington University, St. Louis, MO, USA.
J Affect Disord. 2012 Aug;139(3):283-90. doi: 10.1016/j.jad.2012.02.007. Epub 2012 Mar 5.
Pretreatment brain activity in major depressive disorder correlates with response to antidepressant therapies, including pharmacotherapies and transcranial magnetic stimulation. The purpose of this trial was to examine whether pretreatment regional metabolic activity in selected regions of interest (ROIs) predicts antidepressant response following 12 months of vagus nerve stimulation (VNS) in 15 patients with treatment-resistant major depression (TRMD).
Fluorodeoxyglucose positron emission tomography (FDG PET) was used to assess regional mean relative cerebral metabolic rate for glucose (CMRGlu) in four ROIs (anterior insular, orbitofrontal, anterior cingulate, and dorsolateral prefrontal cortices) at baseline (prior to VNS activation). Depression severity was assessed at baseline and after 12 months of VNS using the Hamilton Depression Rating Scale (HDRS), with response defined as ≥ 50% reduction in HDRS from baseline.
Baseline CMRGlu in the anterior insular cortex differentiated VNS responders (n=11) from nonresponders (n=4) and correlated with HDRS change (r=.64, p=.01). In a regression analysis, lower anterior insular cortex CMRGlu (p=.004) and higher orbitofrontal cortex CMRGlu (p=.047) together predicted HDRS change (R(2)=.58, p=.005). In a whole brain, voxel-wise analysis, baseline CMRGlu in the right anterior insular cortex correlated with HDRS change (r=.78, p=.001).
Sample size was small, limiting statistical power; patients remained on their psychiatric medications; study was open-label and uncontrolled.
This preliminary study suggests that pretreatment regional CMRGlu may be useful in predicting response to VNS in TRMD patients.
在重度抑郁症中，预处理大脑活动与抗抑郁治疗的反应相关，包括药物治疗和经颅磁刺激。本试验的目的是研究在 15 名治疗抵抗性重度抑郁症（TRMD）患者中，经过 12 个月迷走神经刺激（VNS）后，选择的感兴趣区域（ROI）的预处理区域代谢活性是否可以预测抗抑郁反应。
氟代脱氧葡萄糖正电子发射断层扫描（FDG PET）用于评估四个 ROI（前岛叶、眶额皮质、前扣带回和背外侧前额皮质）的区域平均相对脑葡萄糖代谢率（CMRGlu）在基线（VNS 激活之前）。使用汉密尔顿抑郁评定量表（HDRS）在基线和 VNS 治疗 12 个月后评估抑郁严重程度，将 HDRS 较基线降低≥50%定义为应答。
基线时前岛叶皮层的 CMRGlu 区分了 VNS 应答者（n=11）和无应答者（n=4），并与 HDRS 变化相关（r=.64，p=.01）。在回归分析中，较低的前岛叶皮层 CMRGlu（p=.004）和较高的眶额皮层 CMRGlu（p=.047）共同预测了 HDRS 变化（R²=0.58，p=.005）。在全脑体素水平分析中，右侧前岛叶皮层的基线 CMRGlu 与 HDRS 变化相关（r=.78，p=.001）。
样本量较小，限制了统计效力；患者仍在服用精神药物；研究为开放标签和非对照。
这项初步研究表明，预处理的区域 CMRGlu 可能有助于预测 TRMD 患者对 VNS 的反应。
