Kunz Miriam, Mylius Veit, Schepelmann Karsten, Lautenbacher Stefan
Gerontology Section, Department of General Practice, University Medical Center Groningen, University of Groningen, 9700 Groningen, Netherlands.
Department of Neurology, Philipps University Marburg, 35043 Marburg, Germany.
Behav Neurol. 2015;2015:878157. doi: 10.1155/2015/878157. Epub 2015 Dec 14.
There is ample evidence that dementia changes the processing of pain. However, it is not known whether this change in pain processing is related to the general decline in cognitive functioning or whether it may be related to specific domains of cognitive functioning. With the present study we tried to answer this question. We assessed different cognitive domains (orientation, memory, abstract thinking/executive function, aphasia and apraxia, and information processing speed) in 70 older patients with cognitive impairment (mild cognitive impairment up to moderate degrees of dementia). Pain responsiveness was assessed by measuring the nociceptive flexion reflex (NFR) threshold and facial responses to noxious electrical stimulation. Using regression analyses, we assessed which domain of cognitive functioning best predicted variance in pain responsiveness. Variance in pain responsiveness (NFR and facial expressions) was best explained by those items assessing executive functioning even when controlling for overall cognitive performance and memory functioning. The close association between executive functioning and pain responsiveness suggests that dementia-related neurodegeneration in prefrontal areas might result not only in reduced executive functioning but also in a loss of pain inhibitory potency, rendering the patient more vulnerable to pain. Our findings also suggest that pain assessment in dementia should be regularly completed by tests of cognitive functions.
有充分证据表明，痴呆会改变疼痛处理过程。然而，尚不清楚这种疼痛处理的变化是与认知功能的总体下降有关，还是可能与认知功能的特定领域有关。通过本研究，我们试图回答这个问题。我们评估了70名患有认知障碍（从轻度认知障碍到中度痴呆）的老年患者的不同认知领域（定向、记忆、抽象思维/执行功能、失语和失用症以及信息处理速度）。通过测量伤害性屈曲反射（NFR）阈值和对有害电刺激的面部反应来评估疼痛反应性。使用回归分析，我们评估了认知功能的哪个领域最能预测疼痛反应性的差异。即使在控制了整体认知表现和记忆功能的情况下，评估执行功能的项目也能最好地解释疼痛反应性（NFR和面部表情）的差异。执行功能与疼痛反应性之间的密切关联表明，前额叶区域与痴呆相关的神经退行性变可能不仅导致执行功能下降，还会导致疼痛抑制能力丧失，使患者更容易受到疼痛影响。我们的研究结果还表明，痴呆患者的疼痛评估应定期通过认知功能测试来完成。
