Department of Psychology, University of Jaén, Spain.
School of Medicine, Vanderbilt University, Nashville, TN, USA.
Pain Med. 2017 Sep 1;18(9):1778-1786. doi: 10.1093/pm/pnw361.
The pathophysiology of fibromyalgia has been related to central pain sensitization. This study tested a laboratory protocol evaluating responses to slowly repeated evoked pain stimuli (SREP) that may index central pain sensitization in fibromyalgia.
A between-subjects controlled laboratory study.
Twenty-four fibromyalgia patients and 24 healthy participants.
A SREP protocol was administered to all subjects, consisting of a single series of nine low-intensity pressure stimuli of five-second duration and thirty-second interstimulus interval. Subjective evoked pain intensity was assessed with a visual analogical scale. Clinical fibromyalgia pain was assessed with the McGill Pain Questionnaire.
Perceived pain intensity increased during the SREP protocol in fibromyalgia patients but not in healthy participants. Neither pain threshold nor pain tolerance was associated with SREP. Degree of SREP sensitization was associated with McGill Pain Questionnaire-Sensory ratings of fibromyalgia pain. The effect size for differences between the fibromyalgia and healthy control groups was greater, and the overlaps of the groups distributions lower, for SREP sensitization than for traditional evoked pain measures of pain threshold and tolerance. SREP demonstrated higher specificity in discriminating fibromyalgia and control groups relative to pain threshold or tolerance.
A protocol employing a single series of nine low-suprathreshold-intensity slowly repeated pain stimuli elicits increased perceived pain in fibromyalgia patients, consistent with central sensitization despite relatively long interstimulus intervals. SREP appears to be more useful than traditional evoked pain threshold tolerance measures in terms of predicting levels of clinical pain and discriminating between fibromyalgia patients and healthy individuals.
纤维肌痛的病理生理学与中枢性疼痛敏化有关。本研究测试了一种评估缓慢重复诱发疼痛刺激（SREP）反应的实验室方案，该方案可能反映纤维肌痛中的中枢性疼痛敏化。
受试者间对照的实验室研究。
24 例纤维肌痛患者和 24 例健康参与者。
所有受试者均接受 SREP 方案，包括 9 个低强度压力刺激的单次系列，每个刺激持续 5 秒，刺激间隔 30 秒。用视觉模拟评分法评估诱发疼痛的主观强度。用 McGill 疼痛问卷评估临床纤维肌痛疼痛。
在 SREP 方案中，纤维肌痛患者的感知疼痛强度增加，但健康参与者没有增加。疼痛阈值和疼痛耐受力均与 SREP 无关。SREP 敏感化程度与 McGill 疼痛问卷-纤维肌痛疼痛的感觉评分相关。纤维肌痛组和健康对照组之间的差异，SREP 敏感化的效应量较大，且组分布的重叠较小，而传统诱发疼痛的阈值和耐受力测量则较小。与疼痛阈值或耐受力相比，SREP 对区分纤维肌痛和对照组具有更高的特异性。
一项采用 9 个低超阈值强度缓慢重复疼痛刺激的方案，在纤维肌痛患者中引起感知疼痛增加，这与中枢敏化一致，尽管刺激间隔相对较长。与传统诱发疼痛的阈值和耐受力测量相比，SREP 在预测临床疼痛水平和区分纤维肌痛患者和健康个体方面似乎更有用。
