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

描述(由申请人提供)：许多随机临床试验(RCT)表明，针灸是治疗各种疼痛状况的有效方法。仔细研究这些文献就会发现不一致的发现：当RCT将针灸与没有治疗或标准护理的对照组进行比较时，结果往往是确凿的；但当RCT将真正的(真皮)针灸与假针灸进行比较时，结果往往是不确定的，这表明至少有一个愈合成分是由针刺针以外的东西介导的。最近的一项荟萃分析发现，无论真性或假性分组，患者对疼痛缓解的期望是针灸治疗疗效最可靠的预测因子。神经成像研究已经开始确定针灸和安慰剂止痛的可测试机制假说。我们最近对健康受试者的研究表明，在积极预期的背景下，真针和假针刺都能显著缓解疼痛，但每种作用都通过不同的大脑机制发挥作用。目前的建议将测试这些与真针和假针刺后疼痛缓解相关的不同大脑活动模式是否可以在因骨关节炎(OA)而患有慢性膝关节疼痛的患者中复制。我们建议在膝骨性关节炎患者中进行两个实验，直接建立在我们实验室最近的研究基础上。在第一个实验中，我们将系统地提高患者对真针或假针刺后疼痛缓解的积极期望，然后量化期望、行为和脑成像(BOLD FMRI)治疗反应措施之间的关系。在第二个实验中，对真针和假针灸进行了为期5周的纵向机械治疗研究，在第一次和最后一次治疗前后对伤害性刺激进行了fMRI大胆反应，将检查个人对治疗结果的预期，以确定潜在的治疗反应预测因素。这一创新方法的意义在于，它可以为真针和假针灸如何调节痛觉提供明确的科学证据。这些实验的结果不仅将加深我们对针灸和安慰剂止痛机制的理解，还将有助于改进未来的研究方法，并为临床实践提供指导。 公共卫生相关性：拟议的实验结果将直接告知治疗膝骨性关节炎患者的临床医生如何最大限度地发挥针灸治疗的好处。由于这些实验特别询问的问题是，患者对如何治疗将如何缓解疼痛的期望与治疗结果之间的关系，因此结果可能会让护理人员了解骨关节炎和其他慢性疼痛障碍的所有治疗方法。

DESCRIPTION (provided by applicant): 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 tend to be confirmatory when RCTs compare acupuncture with 'no 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 of 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 5-week longitudinal mechanistic treatment study of verum and sham acupuncture, fMRI BOLD responses to noxious stimuli obtained before and after the first and final treatment sessions will be examined with respect to individual expectation of treatment outcome to identify potential treatment response predictors. This significance of this innovative approach is that it could provide clear scientific evidence for how verum and sham acupuncture treatments modulate pain perception. 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. PUBLIC HEALTH RELEVANCE: The results of the proposed experiments will directly inform clinicians who treat patients with osteoarthritis of the knee about how to maximize the benefits of acupuncture treatments. And because the experiments specifically asks the question of what is the relation between a patient's expectation of how a treatment will relieve their pain and the outcome of the treatment, the results will potentially inform care givers about all treatments for osteoarthritis and other chronic pain disorders.