People with Multiple Sclerosis (PwMS) have an over five-fold increased risk of experiencing and being treated for neuropathic pain. Interestingly, pain has been described as a potentially moderating factor of fatigue and depression [1]. Up to 92% of PwMS are affected by fatigue [2] and 24% suffer from depression [3]. Depressed PwMS aremore likely to have pain and there is a positive association between the interference of painful symptoms, and pain severity, with depression severity [4]. Pain, fatigue, and depression are interdependently associated and potentially modifiable [5]. Thus, improving pain symptoms may improve fatigue and depression, which would contribute to an improved quality of life. Conceptually, the study of this MS symptom cluster (pain, fatigue, depression) recognizes that symptoms occur concurrently and that co-occurring symptoms may provide an efficient target for assessment and management. The question at hand is what is the best treatment for this MS symptom cluster? One possible modality is transcranial direct current stimulation (tDCS). To date, no study has investigated the effects of tDCS to improve this MS symptom cluster. We conducted a double blind, sham-controlled, and randomized crossover pilot study. Six moderately disabled PwMS (relapsingremitting MS; 3 female; age 1⁄4 46.7 ± 14.1 yrs.) completed two randomly ordered blocks of stimulation (tDCS or sham). Each block involved five daily sessions. At the first visit, participants completed the, Fatigue Severity Scale (FSS), visual analog scale for pain (VAS), and Beck Depression Inventory (BDI) questionnaires. Isokinetic leg strength and fatigue testing were also performed. Leg strength was determined via five sets of one isokinetic maximal flexion and extension (60 /s) and objectively defined the more-affected leg. A tDCS device (Soterix Medical Inc., New York, NY) delivered a small direct current through two surface sponge electrodes (5 cm 7 cm, soaked with 15 mM NaCL). The anode was placed over the M1 representation of the more-affected leg and the cathode was placed over the contralateral supraorbit. The isokinetic fatigue test (FT) involved 40 continuous maximal contractions (concentric/concentric, 120 /s) of the knee extensors and flexors. The FT was performed using the weaker (more-affected) leg. The peak work of each repetitionwas used to calculate the fatigue index (FI-W) as follows: (total work performed in the last half/total work performed in the first half) * 100. The stimulation blocks (tDCS or sham) were performed in a randomized order. For tDCS, the participants received 2 mA of stimulation for 20 min while seated comfortably and quietly. The intensity started at 0 mA and incrementally increased to 2mA. At minute 20, the current was gradually reduced

中文翻译：

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经颅直流电刺激 (tDCS) 用于治疗多发性硬化症症状群

患有多发性硬化症 (PwMS) 的人经历和接受神经性疼痛治疗的风险增加了五倍以上。有趣的是，疼痛被描述为疲劳和抑郁的潜在调节因素 [1]。高达 92% 的 PwMS 受疲劳影响 [2]，24% 患有抑郁症 [3]。抑郁的 PwMS 更可能出现疼痛，并且疼痛症状的干扰和疼痛严重程度与抑郁严重程度呈正相关 [4]。疼痛、疲劳和抑郁是相互关联的，并且可能是可以改变的 [5]。因此，改善疼痛症状可以改善疲劳和抑郁，这将有助于提高生活质量。从概念上讲，对这种 MS 症状群（疼痛、疲劳、抑郁症）认识到症状同时发生，同时出现的症状可以为评估和管理提供有效的目标。手头的问题是这种 MS 症状群的最佳治疗方法是什么？一种可能的方式是经颅直流电刺激 (tDCS)。迄今为止，还没有研究调查 tDCS 对改善这种 MS 症状群的影响。我们进行了一项双盲、假对照和随机交叉试点研究。6 名中度残疾的 PwMS（复发缓解型 MS；3 名女性；年龄 1⁄4 46.7 ± 14.1 岁）完成了两个随机排序的刺激块（tDCS 或假手术）。每个区块包括五个每日时段。在第一次访问时，参与者完成了疲劳严重程度量表 (FSS)、疼痛视觉模拟量表 (VAS) 和贝克抑郁量表 (BDI) 问卷。还进行了等速腿部力量和疲劳测试。腿部力量是通过五组一个等速最大屈曲和伸展 (60 / s) 来确定的，并客观地定义了受影响更大的腿。一个 tDCS 设备（Soterix Medical Inc., New York, NY）通过两个表面海绵电极（5 cm×7 cm，用 15 mM NaCL 浸泡）提供小的直流电。阳极放置在受影响较大腿的 M1 代表上，阴极放置在对侧眶上。等速疲劳试验 (FT) 涉及膝伸肌和屈肌的 40 次连续最大收缩（同心/同心，120 次/秒）。FT 是使用较弱（受影响较大）的腿进行的。每次重复的峰值功用于计算疲劳指数（FI-W）如下：（上半场的总工作量/上半场的总工作量）* 100。刺激块（tDCS 或假）以随机顺序进行。对于 tDCS，参与者在舒适安静地坐着的情况下接受 2 mA 的刺激 20 分钟。强度从 0 mA 开始并逐渐增加到 2 mA。在第 20 分钟，电流逐渐减小