School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.
Department of Obstetrics Gynecology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.
Am J Obstet Gynecol. 2017 Jun;216(6):584.e1-584.e11. doi: 10.1016/j.ajog.2017.02.049. Epub 2017 Mar 14.
Provoked vestibulodynia is a highly prevalent condition characterized by acute recurrent pain located at the vaginal entrance in response to pressure application or attempted vaginal penetration. Despite a wide variety of treatments offered to women with provoked vestibulodynia, a high proportion of women are refractory to conventional treatment. Transcranial direct-current stimulation is a noninvasive brain stimulation technique that has been shown effective for improving various chronic pain conditions. Growing evidence suggests that the central nervous system could play a key role in provoked vestibulodynia. Targeting the central nervous system could therefore be a promising treatment for women with provoked vestibulodynia.
The purpose of this study was to evaluate and compare the efficacy of active and sham transcranial direct-current stimulation in reducing pain intensity during intercourse in patients with provoked vestibulodynia.
We conducted a triple-blind, parallel-group, randomized controlled trial. Women aged 17-45 years diagnosed with provoked vestibulodynia by a gynecologist using a validated protocol were randomized to 10 sessions of either active transcranial direct-current stimulation (intensity = 2 mA) or 10 sessions of sham transcranial direct-current stimulation, over a 2-week period. Both active and sham transcranial direct-current stimulation were applied for 20 minutes, with the anode positioned over the primary motor cortex, and the cathode over the contralateral supraorbital area. Outcome measures were collected at baseline, 2 weeks after treatment, and at 3-month follow-up by an evaluator blinded to group assignment. The primary objective was to assess pain intensity during intercourse, using a numerical rating scale. Secondary outcomes focused on sexual function and distress, vestibular sensitivity, psychological distress, treatment satisfaction, and patient impression of change. Statistical analyses were conducted on the intention-to-treat basis, and treatment effects were evaluated using a mixed linear model for repeated measures.
A total of 40 patients were randomly assigned to receive either active (n = 20) or sham (n = 20) transcranial direct-current stimulation treatments from November 2014 through February 2016. Baseline characteristics were similar between the active and sham transcranial direct-current stimulation groups. In full compliance with the study protocol, every participant followed all courses of the study treatment, including assessments at 2-week and 3-month follow-up. Pain during sexual intercourse was not significantly different between active and sham treatment groups 2 weeks after treatment (P = .84) and at follow-up (P = .09). Mean baseline and 2-week assessment pain intensity were, respectively, 6.8 (95% confidence interval, 5.9-7.7) and 5.6 (95% confidence interval, 4.7-6.5) for active transcranial direct-current stimulation (P = .03) vs 7.5 (95% confidence interval, 6.6-8.4) and 5.7 (95% confidence interval, 4.8-6.6) for sham transcranial direct-current stimulation (P = .001). Nonsignificant differences between the 2 groups were also found in their sexual function and distress after treatment (P > .20) and at follow-up (P > .10). Overall, at 2-week assessment 68% assigned to active transcranial direct-current stimulation reported being very much, much, or slightly improved compared to 65% assigned to sham transcranial direct-current stimulation (P = .82), and still comparable at follow-up: 42% vs 65%, respectively (P = .15).
Findings suggest that active transcranial direct-current stimulation is not more effective than sham transcranial direct-current stimulation for reducing pain in women with provoked vestibulodynia. Likewise, no significant effects were found on sexual function, vestibular sensitivity, or psychological distress.
诱发外阴痛是一种高度流行的疾病，其特征为阴道入口处的急性复发性疼痛，对压力应用或试图阴道插入有反应。尽管为患有诱发外阴痛的女性提供了广泛的治疗方法，但很大一部分女性对常规治疗没有反应。经颅直流电刺激是一种非侵入性的大脑刺激技术，已被证明对改善各种慢性疼痛状况有效。越来越多的证据表明，中枢神经系统可能在外阴痛中发挥关键作用。因此，针对中枢神经系统可能是治疗患有诱发外阴痛的女性的一种有前途的方法。
本研究旨在评估和比较活跃和假经颅直流电刺激在减轻患有诱发外阴痛的女性性交时疼痛强度方面的疗效。
我们进行了一项三盲、平行组、随机对照试验。由妇科医生使用经过验证的方案诊断为患有诱发外阴痛的 17-45 岁女性被随机分配至 10 次活跃的经颅直流电刺激（强度= 2 mA）或 10 次假经颅直流电刺激，在 2 周内完成。在 20 分钟内，均应用活跃和假经颅直流电刺激，阳极置于初级运动皮层，阴极置于对侧眶上区域。在基线、治疗后 2 周和 3 个月随访时由对分组情况不知情的评估人员收集结果。主要目的是使用数字评分量表评估性交时的疼痛强度。次要结果集中在性功能和困扰、前庭敏感性、心理困扰、治疗满意度和患者对变化的印象上。统计分析基于意向治疗原则进行，使用混合线性模型进行重复测量评估治疗效果。
共有 40 名患者于 2014 年 11 月至 2016 年 2 月期间随机分配接受活跃（n=20）或假（n=20）经颅直流电刺激治疗。活跃和假经颅直流电刺激组的基线特征相似。在完全遵守研究方案的情况下，每位参与者都遵循了所有的研究治疗过程，包括 2 周和 3 个月随访时的评估。治疗后 2 周（P=.84）和随访时（P=.09），活跃和假治疗组的性交疼痛无显著差异。活跃经颅直流电刺激的平均基线和 2 周评估疼痛强度分别为 6.8（95%置信区间，5.9-7.7）和 5.6（95%置信区间，4.7-6.5）（P=.03），而假经颅直流电刺激的分别为 7.5（95%置信区间，6.6-8.4）和 5.7（95%置信区间，4.8-6.6）（P=.001）。治疗后（P＞.20）和随访时（P＞.10），两组的性功能和困扰也未发现显著差异。总体而言，在 2 周评估时，与接受假经颅直流电刺激的 65%相比，68%接受活跃经颅直流电刺激的患者报告说有很大、很大或稍微改善（P=.82），在随访时仍然相似：分别为 42%和 65%（P=.15）。
研究结果表明，与假经颅直流电刺激相比，活跃经颅直流电刺激并不能更有效地减轻患有诱发外阴痛的女性的疼痛。同样，在性功能、前庭敏感性或心理困扰方面也没有发现显著影响。
