Departament of Geriatrics and Gerontology, Federal University of São Paulo, São Paulo, SP, Brazil; Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo, São Paulo, SP, Brazil.
Department of Evidence-Based Medicine, Brazilian Cochrane Centre, Federal University of São Paulo, São Paulo, SP, Brazil.
Brain Stimul. 2021 May-Jun;14(3):477-487. doi: 10.1016/j.brs.2021.02.018. Epub 2021 Mar 5.
Although evidence has indicated a positive effect of transcranial direct current stimulation (tDCS) on reducing pain, few studies have focused on the elderly population with knee osteoarthritis (KOA).
To evaluate whether tDCS reduces KOA pain in elderly individuals with a dysfunctional descending pain inhibitory system (DPIS).
In a double-blind trial, individuals ≥ 60 years with KOA pain and a dysfunctional DPIS, we randomly assigned patients to receive 15 daily sessions of 2 mA tDCS over the primary motor cortex (anode) and contralateral supraorbital area (cathode) (M1-SO) for 20 min or sham tDCS. Change in pain perception indexed by the Brief Pain Inventory (BPI) at the end of intervention was the primary outcome. Secondary outcomes included: disability, quantitative sensory testing, pain pressure threshold and conditioned pain modulation (CPM). Subjects were followed-up for 2 months.
Of the 104 enrolled subjects, with mean (SD) age of 73.9 (8.01) years and 88 (84.6%) female, 102 finished the trial. In the intention-to-treat analysis, the active tDCS group had a significantly greater reduction in BPI compared to the sham group (difference, 1.59; 95% CI, 0.95 to 2.23; P < 0.001; Cohen's d, 0.58); and, also a significantly greater improvement in CPM-pressure in the knee (P = 0.01) and CPM-pain in the hand (P = 0.01). These effects were not sustained at follow-up. The intervention was well tolerated, with no severe adverse effects.
M1-SO tDCS is associated with a moderate effect size in reducing pain in elderly patients with KOA after 15 daily sessions of stimulation. This intervention has also shown to modulate the DPIS.
虽然有证据表明经颅直流电刺激（tDCS）对减轻疼痛有积极作用，但很少有研究关注膝骨关节炎（KOA）的老年人群。
评估 tDCS 是否能降低功能失调的下行疼痛抑制系统（DPIS）的老年 KOA 患者的疼痛。
在一项双盲试验中，我们将 60 岁以上有 KOA 疼痛和功能失调 DPIS 的患者随机分为接受 15 天每天 2 mA tDCS 治疗组，刺激部位为初级运动皮层（阳极）和对侧眶上区（阴极）（M1-SO），共 20 分钟，或假刺激治疗组。干预结束时疼痛感知的变化由简明疼痛量表（BPI）评估，这是主要结局。次要结局包括：残疾、定量感觉测试、疼痛压力阈值和条件性疼痛调制（CPM）。受试者随访 2 个月。
在纳入的 104 名受试者中，平均（SD）年龄为 73.9（8.01）岁，88 名（84.6%）为女性，有 102 名完成了试验。在意向治疗分析中，与假刺激组相比，活性 tDCS 组的 BPI 显著降低（差值，1.59；95%CI，0.95 至 2.23；P<0.001；Cohen's d，0.58）；并且，在膝关节 CPM-压力（P=0.01）和手部 CPM-疼痛（P=0.01）方面也有显著改善。这些效果在随访时并未持续。干预措施耐受性良好，无严重不良反应。
在 15 天的刺激后，M1-SO tDCS 与减轻老年 KOA 患者疼痛的中等效应量相关。这种干预措施还显示出对 DPIS 的调节作用。
