Department of Anesthesiology, Perioperative and Pain Medicine, Division of Pain Medicine, Stanford University School of Medicine, Stanford, California, USA.
Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina, USA.
Sci Rep. 2019 Jul 3;9(1):9633. doi: 10.1038/s41598-019-45961-y.
Neural responses to incentives are altered in chronic pain and by opioid use. To understand how opioid use modulates the neural response to reward/value in chronic pain, we compared brain functional magnetic resonance imaging (fMRI) responses to a monetary incentive delay (MID) task in patients with fibromyalgia taking opioids (N = 17), patients with fibromyalgia not taking opioids (N = 17), and healthy controls (N = 15). Both groups of patients with fibromyalgia taking and not taking opioids had similar levels of pain, psychological measures, and clinical symptoms. Neural responses in the nucleus accumbens to anticipated reward and non-loss outcomes did not differ from healthy controls in either fibromyalgia group. However, neural responses in the medial prefrontal cortex differed, such that patients with fibromyalgia not taking opioids demonstrated significantly altered responses to anticipated rewards and non-loss outcomes compared to healthy controls, but patients with fibromyalgia taking opioids did not. Despite limitations including the use of additional non-opioid medications by fibromyalgia patients taking opioids, these preliminary findings suggest relatively "normalized" neural responses to monetary incentives in chronic pain patients who take opioids versus those who do not.
在慢性疼痛和阿片类药物使用中，对激励的神经反应会发生改变。为了了解阿片类药物使用如何调节慢性疼痛患者对奖励/价值的神经反应，我们比较了接受阿片类药物治疗的纤维肌痛患者（N=17）、未接受阿片类药物治疗的纤维肌痛患者（N=17）和健康对照组（N=15）在进行货币激励延迟（MID）任务时的大脑功能磁共振成像（fMRI）反应。两组接受阿片类药物治疗和未接受阿片类药物治疗的纤维肌痛患者的疼痛、心理测量和临床症状水平相似。在接受阿片类药物治疗和未接受阿片类药物治疗的纤维肌痛患者中，无论是哪一组，对预期奖励和非损失结果的伏隔核神经反应与健康对照组并无不同。然而，内侧前额叶皮层的神经反应不同，未接受阿片类药物治疗的纤维肌痛患者对预期奖励和非损失结果的反应与健康对照组相比明显改变，但接受阿片类药物治疗的纤维肌痛患者则没有。尽管存在一些局限性，包括接受阿片类药物治疗的纤维肌痛患者同时使用了其他非阿片类药物，但这些初步发现表明，在接受阿片类药物治疗的慢性疼痛患者中，与不接受阿片类药物治疗的患者相比，对金钱奖励的神经反应相对“正常化”。
