Gastrointestinal Physiology Department, St. Mark’s Hospital Campus, Imperial College, Harrow, Middlesex, UK.
Am J Physiol Gastrointest Liver Physiol. 2011 Jun;300(6):G1086-93. doi: 10.1152/ajpgi.00553.2010. Epub 2011 Feb 24.
The objective of this study was to determine whether cortical evoked potentials (CEPs) can define neurophysiological patterns in irritable bowel syndrome (IBS). In this prospective study of consecutive patients attending secondary and tertiary centers, patients with Rome II-defined IBS underwent rectal sensory and pain threshold (RST and RPT, respectively) testing with electrical stimulation on three separate visits. CEPs were collated for 75% pain thresholds, and anxiety [Spielberger State-Trait Anxiety Inventory (SSTAI)] questionnaires were completed. Subjects were 33 IBS patients (27 female, mean age 40.1 yr) and 21 healthy controls (14 female, mean age 31.4 yr). At visit 3, RPT was significantly lower [mean (95% CI)] in IBS patients than in control subjects: 58.2 mA (48.0-68.5) vs. 79.5 mA (69.3-89.6) (P < 0.01). No significant differences were observed in CEP latencies and amplitudes between visits 1, 2, and 3 within each group, except P2 latency for controls (P = 0.04) and N2 latency (P = 0.04) and N2 amplitude (P = 0.02) for IBS patients. Group comparisons showed significant differences in 3-day mean RPT, CEP amplitudes, and CEP latencies between IBS patients and controls. RPT <50 mA and P1 latency >106 ms were identified four IBS subgroups: 24% were hypersensitive, 12% were hypervigilant, 15% were hyposensitive, and 49% exhibited normal P1 latency and pain threshold. CEPs are reliable and reproducible measures of early sensory processing. Identification of four IBS neurophysiological patterns highlights its heterogeneous nature. These findings mark the first step toward personalized medicine in IBS, whereby therapy may be directed at the underlying physiological process.
本研究旨在确定皮质诱发电位（CEPs）是否可以定义肠易激综合征（IBS）的神经生理模式。在这项连续患者参加二级和三级中心的前瞻性研究中，罗马 II 定义的 IBS 患者在三次单独就诊时接受直肠感觉和疼痛阈值（RST 和 RPT，分别）测试与电刺激。收集 75%疼痛阈值的 CEPs，并完成焦虑[斯皮尔伯格状态-特质焦虑问卷（SSTAI）]问卷。受试者为 33 例 IBS 患者（27 例女性，平均年龄 40.1 岁）和 21 例健康对照者（14 例女性，平均年龄 31.4 岁）。在第 3 次就诊时，IBS 患者的 RPT 明显低于对照组：58.2 mA（48.0-68.5）与 79.5 mA（69.3-89.6）（P <0.01）。在每组的第 1、2 和 3 次就诊中，CEPs 潜伏期和振幅之间没有观察到显著差异，但对照组的 P2 潜伏期（P = 0.04）和 IBS 患者的 N2 潜伏期（P = 0.04）和 N2 振幅（P = 0.02）。组间比较显示，IBS 患者与对照组之间 3 天平均 RPT、CEPs 振幅和 CEP 潜伏期存在显著差异。RPT <50 mA 和 P1 潜伏期> 106 ms 确定了四个 IBS 亚组：24%为超敏组，12%为超敏组，15%为低敏组，49%表现出正常的 P1 潜伏期和疼痛阈值。CEPs 是早期感觉处理的可靠和可重复的测量方法。确定四个 IBS 神经生理模式突出了其异质性。这些发现标志着迈向 IBS 个体化医学的第一步，治疗方法可能针对潜在的生理过程。
