Department of Psychology, University of Jaén, Spain.
Clin Exp Rheumatol. 2022 Jun;40(6):1202-1209. doi: 10.55563/clinexprheumatol/n280oi. Epub 2022 Jun 23.
Fibromyalgia (FM) is associated with central pain sensitisation, autonomic alterations and neuropathy in small nerve fibres. This study aimed to analyse the association between tonic sweating and central pain sensitisation in FM.
Fifty-eight FM patients and thirty healthy women were assessed in terms of slowly repeated evoked pain (SREP), as a measure of central sensitisation. Sweating was evaluated by skin conductance (SC), as a sympathetic autonomic measure secondarily indexing possible small nerve fibre peripheral neuropathy. Clinical and psychological factors were evaluated through questionnaire measures.
FM patients displayed smaller SC values than healthy controls, and SREP sensitisation was only observed in FM patients. Pain threshold and tolerance were also lower in the patient sample. Clinical symptoms (pain, fatigue, insomnia) only correlated significantly with SREP sensitisation. SC was inversely related to SREP sensitisation, and this association persisted after statistically controlling for levels of catastrophising and antidepressant use.
These results suggest that central pain sensitisation, proposed as a main pathophysiological mechanism of FM, may depend on sympathetic autonomic deficiencies, suggestive of small nerve fibres neuropathy. Future studies should aim to replicate these results using other central pain sensitisation measures and direct measures of neuropathy or small nerve fibre density.
纤维肌痛（FM）与中枢性疼痛敏化、自主神经改变和小纤维神经病变有关。本研究旨在分析 FM 患者的紧张性多汗与中枢性疼痛敏化之间的关系。
对 58 名 FM 患者和 30 名健康女性进行缓慢重复诱发疼痛（SREP）评估，作为中枢敏化的测量指标。通过皮肤电导（SC）评估出汗，作为可能的小纤维外周神经病变的交感自主指标。通过问卷调查评估临床和心理因素。
FM 患者的 SC 值明显低于健康对照组，且仅在 FM 患者中观察到 SREP 敏化。患者组的疼痛阈值和耐受度也较低。临床症状（疼痛、疲劳、失眠）仅与 SREP 敏化显著相关。SC 与 SREP 敏化呈负相关，且在统计学控制了灾难化和抗抑郁药使用水平后，这种关联仍然存在。
这些结果表明，作为 FM 主要病理生理机制的中枢性疼痛敏化可能依赖于交感自主神经缺陷，提示小纤维神经病变。未来的研究应使用其他中枢性疼痛敏化测量指标和直接的神经病变或小纤维密度测量来重复这些结果。
