Compton Peggy, Halabicky Olivia M, Aryal Subhash, Badiola Ignacio
Family and Community Health, School of Nursing, University of Pennsylvania, Claire M. Fagin Hall, Room 402, 418 Curie Blvd, Philadelphia, PA, 19104-4217, USA.
Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Pain Ther. 2022 Mar;11(1):303-313. doi: 10.1007/s40122-021-00348-8. Epub 2022 Jan 12.
The degree to which opioid-induced hyperalgesia contributes to the pain experience of patients with chronic pain remains relatively undescribed. The objective of this pilot study was to determine if experimental pain responses improve in patients with chronic pain as they undergo a planned opioid taper.
This was a prospective observational study. Seven patients with chronic neuropathic pain on at least 120 mg morphine equivalents/day were enrolled. The participants were followed over the course of an individualized opioid taper to a lower dose. Measures of experimental pain sensitivity, including indicators of central pain modulation, were collected on a biweekly basis; in addition, measures of function and quality of life were collected monthly. The effect of opioid taper on pain responses and functional outcomes over time were examined using longitudinal mixed-effects regression modeling and general linear regression modeling with regularization as a function of baseline dose, end dose, and taper rate.
In this small sample of patients undergoing highly individualized and variable opioid taper, the opioid taper was significantly associated with improved pain responses to the cold-pressor test, with the pain threshold on average increasing by 1.14 s every 6 weeks (p = 0.0084, 95% confidence interval [CI] for 6-week change 0.3039-2.0178) and pain tolerance on average increasing by 2.87 s every 6 weeks (p = 0.0026, 95% CI for 6-week change 1.02-4.7277). Taper-related changes in central pain modulation were not observed, although conditioned modulation trended toward improvement by the completion of opioid taper. Similarly, no declines in function and quality of life were observed with the opioid taper, suggesting stability despite decreased opioid dose.
Opioid taper was associated with improvements in experimental pain responses without a decline in function and quality of life, suggestive of diminished opioid-induced hyperalgesia in this clinical sample.
ClinicalTrials.gov identifier, NCT03912298.
阿片类药物诱导的痛觉过敏对慢性疼痛患者疼痛体验的影响程度仍相对缺乏描述。这项初步研究的目的是确定慢性疼痛患者在进行计划中的阿片类药物减量时，其实验性疼痛反应是否会改善。
这是一项前瞻性观察性研究。纳入了7名每天至少服用120毫克吗啡当量的慢性神经性疼痛患者。参与者在个体化的阿片类药物减量至较低剂量的过程中接受随访。每两周收集一次实验性疼痛敏感性指标，包括中枢性疼痛调制指标；此外，每月收集一次功能和生活质量指标。使用纵向混合效应回归模型和带正则化的一般线性回归模型，以基线剂量、终末剂量和减量速率为函数，研究阿片类药物减量随时间对疼痛反应和功能结局的影响。
在这一小群接受高度个体化且变化的阿片类药物减量的患者中，阿片类药物减量与冷加压试验的疼痛反应改善显著相关，疼痛阈值平均每6周增加1.14秒（p = 0.0084，6周变化的95%置信区间[CI]为0.3039 - 2.0178），疼痛耐受平均每6周增加2.87秒（p = 0.0026，6周变化的95%CI为1.02 - 4.7277）。未观察到与减量相关的中枢性疼痛调制变化，尽管条件调制在阿片类药物减量完成时趋于改善。同样，阿片类药物减量过程中未观察到功能和生活质量下降，表明尽管阿片类药物剂量降低，但仍保持稳定。
阿片类药物减量与实验性疼痛反应改善相关，且功能和生活质量未下降，提示该临床样本中阿片类药物诱导的痛觉过敏有所减轻。
ClinicalTrials.gov标识符，NCT03912298。
