Influencing factors of brain alterations in chronic pain

近年来，临床参数和成像数据以及预测性生物标志物的关联使人们对慢性疼痛的神经生物学有了有价值的见解。慢性背痛患者的大脑表现为内侧前额叶皮层、扣带回和前额叶的灰质体积减少。然而，各种疼痛综合征的结果仍然非常不一致，这在很大程度上可以归因于个体研究中的组规模太小。在常见疼痛疾病的情况下，也可以使用基于人群的研究分析，以提供必要的组规模。通过拟议的项目，我们打算缩小这一差距。我们分析了基于体素的灰质体积（GMV）的体积，在两个纵向的基于人群的队列的SHIP研究（波美拉尼亚健康研究）和纵向的临床数据集。该项目的总体目标是通过使用两个广泛人群队列中各种疼痛综合征的现有信息来表征慢性疼痛的神经生物学。此外，我们补充了临床研究中基于人群的队列中的观察结果。这些包括颅下颌疼痛患者和与复杂区域疼痛综合征（CRPS）相关的上肢疼痛患者，CRPS是一种神经性疼痛综合征。基于人群的队列研究的优势在于全面收集数据，在常见疾病的情况下，还可以记录生物标志物，这些生物标志物可以预测谁将在调查后期间发展这些综合征。患者检查的优势在于采用循证治疗方法进行具体调查。这又使得有可能确定治疗应答者的纵向预测因子。这两个队列的具体之处在于，它们与大量无急性和慢性疼痛的匹配对照组一起在相同的MRI上进行测量。这使得数据池具有独特的同质性。此外，这两个队列可以更仔细地观察所有综合征中GMV的共同变化，观察每个综合征的具体变化，还可以比较其他精神疾病的具体变化，这些疾病在个体症状（抑郁和焦虑）方面与慢性疼痛有很大的重叠。最终，记录大量参数，也可以通过中介分析计算与灰质变化的关系。总之，申请纵向可用数据集的项目提供了一个独特的机会来识别慢性疼痛的生物标志物并测试其特异性-特别是在GMV改变方面。

Associations of clinical parameters and imaging data as well as predictive biomarkers have enabled valuable insights into the neurobiology of chronic pain in recent years. The brains of patients with chronic back pain show characteristic volume reductions in the gray matter of the brain in the medial prefrontal cortex, the cingulate gyrus, and the anterior insula. However, the results for various pain syndromes are still very inconsistent, which can largely be attributed to group sizes that are too small in the individual studies.In the case of frequent pain disorders, analyzes from population-based studies can also be used that can provide the necessary group sizes. With the proposed project we intend to close this gap. We analyze the volume of the gray matter volume (GMV) based on voxels in two longitudinal population-based cohorts of the SHIP study (Study of health in Pomerania) and in longitudinal clinical data sets. The overall goal of this project is to characterize the neurobiology of chronic pain by using existing information on various pain syndromes in two extensive population-based cohorts. In addition, we supplement the observations made in population-based cohorts with clinical studies. These include patients with craniomandibular pain and patients with upper extremity pain associated with complex regional pain syndrome (CRPS), which is a neuropathic pain syndrome. The advantage of the population-based cohort studies lies in the comprehensive collection of data, which in the case of frequently occurring diseases also enables the recording of biomarkers that can predict who will develop these syndromes in the post-survey period. The advantage of the patient examinations lies in the specific surveys with an evidence-based therapy method. This in turn makes it possible to determine longitudinal predictors for therapy responders. What is specific about both cohorts is that they were measured on the same MRI together with a large number of matched controls free of acute and chronic pain. This enables a unique homogeneity of the data pool. In addition, both cohorts enable a closer look at the common changes in GMV in all syndromes, a look at specific changes for each individual syndrome, but also a comparison of the specific changes to other mental illnesses that show large overlaps with chronic pain with regard to individual symptoms (depression and anxiety). Ultimately, with the large number of parameters recorded, relations with changes in gray matter can also be calculated by means of mediation analyzes. In summary, the project applied for with the longitudinally available data sets offers a unique opportunity to identify biomarkers for chronic pain and to test their specificity- especially with respect to GMV alterations.