Abstract:
Adverse life experiences (ALEs) are associated with hyperalgesia and chronic pain, but the underlying mechanisms are poorly understood. One potential mechanism is hyperexcitability of spinal neurons (ie, central sensitization). Given that Native Americans (NAs) are more likely to have ALEs and to have a higher prevalence of chronic pain, the relationship between ALEs and spinal hyperexcitability might contribute to their pain risk. The present study assessed temporal summation of the nociceptive flexion reflex (TS-NFR; a correlate of spinal hyperexcitability) and pain (TS-Pain) in 246 healthy, pain-free non-Hispanic whites and NAs. The Life Events Checklist was used to assess the number of ALEs. Multilevel growth models were used to predict TS-NFR and TS-Pain, after controlling for age, perceived stress, psychological problems, negative and positive affect, and painful stimulus intensity. ALEs and negative affect were significantly associated with greater pain, but not enhanced TS-Pain. By contrast, ALEs were associated with enhanced TS-NFR. Race did not moderate these relationships. This finding implies that ALEs promote hyperalgesia as a result of increased spinal neuron excitability. Although relationships between ALEs and the nociceptive flexion reflex/pain were not stronger in NAs, given prior evidence that NAs experience more ALEs, this factor might contribute to the higher prevalence of chronic pain in NAs. PERSPECTIVE: This study found a dose-dependent relationship between ALEs and spinal neuron excitability. Although the relationship was not stronger in NAs than non-Hispanic whites, given prior evidence that NAs experience more ALEs, this could contribute to the higher prevalence of chronic pain in NAs.
摘要:
不良生活经历(ALE)与痛觉过敏和慢性疼痛有关,但潜在的机制却知之甚少。一种潜在的机制是脊髓神经元的过度兴奋(即,中央敏化)。鉴于美洲原住民(NAs)更有可能患有ALE,并且慢性疼痛的患病率更高,ALE与脊髓过度兴奋之间的关系可能导致其疼痛风险.本研究评估了246例健康患者的伤害性屈曲反射(TS-NFR;脊髓过度兴奋的相关性)和疼痛(TS-疼痛)的时间总和,无痛的非西班牙裔白人和NAs。生活事件清单用于评估ALE的数量。多水平生长模型用于预测TS-NFR和TS-疼痛,在控制了年龄之后,感知压力,心理问题,消极和积极的影响,和痛苦的刺激强度。ALE和负面影响与更大的疼痛显着相关,但不是增强TS-疼痛。相比之下,ALE与TS-NFR增强相关。种族并没有缓和这些关系。这一发现暗示ALE促进痛觉过敏是脊髓神经元兴奋性增加的结果。尽管在NAs中,ALE与伤害性屈曲反射/疼痛之间的关系并不强烈,鉴于先前的证据表明NA经历了更多的ALE,这一因素可能导致NAs中慢性疼痛的患病率较高.结果:本研究发现ALE与脊髓神经元兴奋性之间存在剂量依赖性关系。尽管NAs的关系并不比非西班牙裔白人强,鉴于先前的证据表明NA经历了更多的ALE,这可能导致NAs中慢性疼痛的患病率更高.