An fMRI study of expectancy on acupuncture treatment outcomes in knee OA

许多随机临床试验（RCT）表明针灸是一种有效的治疗各种疼痛的条件。仔细研究这些文献显示不一致的发现：当RCT将针灸与<$not treatment <$or <$standard care <$controls进行比较时，结果是确定的;但当RCT将真正的（verum）针灸与假针灸进行比较时，结果是不确定的，这表明至少有一种愈合成分是由针灸针以外的东西介导的。 最近的一项荟萃分析确定，患者对疼痛缓解的期望是针灸治疗效果的最有力的预测因素，无论是真针组还是假针组。神经影像学研究已经开始确定针灸和安慰剂镇痛的可检验的机制假设。我们最近对健康受试者的研究表明，在积极期望的背景下，真针和假针都能显著缓解疼痛，但每种作用都是通过可分离和不同的大脑机制实现的。目前的提议将测试这些与verum和假针灸后疼痛缓解相关的不同大脑活动模式是否可以在患有骨关节炎（OA）所致慢性膝关节疼痛的患者中复制。 我们提出了两个实验，直接建立在我们实验室最近的研究膝关节骨性关节炎患者。在第一个实验中，我们将系统地提高患者对真针或假针后疼痛缓解的积极期望，然后量化治疗反应的期望，行为和脑成像（BOLD fMRI）测量之间的关系。在第二个实验中，类似的积极期望的提高治疗将进行比较，标准治疗和等待名单控制在6周的纵向机制治疗研究verum针灸。将检查在第一次治疗前和第6次治疗后获得的fMRI BOLD数据，以确定潜在的治疗反应预测因子。 他的创新方法的重要性在于，它可以为期望如何调节镇痛治疗的影响提供明确的科学证据。这些实验的结果不仅将促进我们对针灸和安慰剂镇痛机制的理解，还有助于完善未来的研究方法，并为临床实践提供信息。

Many randomized clinical trials (RCTs) show acupuncture to be an effective treatment for diverse pain conditions. A closer look at this literature shows inconsistent findings: results lend to be confirmatory when RCTs compare acupuncture with ¿not treatment¿ or ¿standard care¿ controls; but inconclusive when RCTs compare genuine (verum) acupuncture with sham acupuncture suggesting that at least one healing component is mediated by something other than the acupuncture needles. A recent meta-analysis identified patient expectation of pain relief as the most robust predictor acupuncture treatment efficacy, regardless of verum or sham group assignment. Neuroimaging studies have begun identifying testable mechanistic hypotheses for both acupuncture and placebo analgesia. Our recent studies on healthy subjects demonstrate that in the context of positive expectation, both verum and sham acupuncture significantly relieve pain, however each functions via separable and distinct brain mechanisms. The current proposal will test whether these distinct brain activity patterns associated with pain relief following verum and sham acupuncture can be replicated in patients suffering from chronic knee pain due to osteoarthritis (OA). We propose two experiments in patients with knee OA that directly build upon recent research in our laboratory. In the first experiment we will systematically boost patients¿ positive expectation for pain relief following verum or sham acupuncture, then quantify the relation between expectation, behavioral , and brain imaging (BOLD fMRI) measures of treatment response. In the second experiment, a similar boost of positive expectation for treatment will be compared to standard treatment and to waitlist control in a 6-week longitudinal mechanistic treatment study of verum acupuncture. fMRI BOLD data obtained before the first and after the 6th treatment sessions will be examined with respect to individual expectation of treatment outcome to identify potential treatment responses predictors. The significance of his innovative approach is that it could provide clear scientific evidence for how expectation modulates the impact of an analgesic treatment. The results of these experiments will advance our understanding of not only acupuncture and placebo analgesia mechanisms, but also help refine future research methods, and inform clinical practice.