Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota; Clinical Enteric Neuroscience Translational and Epidemiological Research, Mayo Clinic, Rochester, Minnesota.
Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota; Clinical Enteric Neuroscience Translational and Epidemiological Research, Mayo Clinic, Rochester, Minnesota.
Gastroenterology. 2013 Feb;144(2):314-322.e2. doi: 10.1053/j.gastro.2012.10.049. Epub 2012 Nov 7.
BACKGROUND & AIMS: Disordered defecation is attributed to pelvic floor dyssynergia. However, clinical observations indicate a spectrum of anorectal dysfunctions. The extent to which these disorders are distinct or overlap is unclear; anorectal manometry might be used in diagnosis, but healthy persons also can have abnormal rectoanal pressure gradients during simulated evacuation. We aimed to characterize phenotypic variation in constipated patients through high-resolution anorectal manometry.
We evaluated anorectal pressures, measured with high-resolution anorectal manometry, and rectal balloon expulsion time in 62 healthy women and 295 women with chronic constipation. Phenotypes were characterized by principal components analysis of high-resolution anorectal manometry.
Two healthy persons and 71 patients had prolonged (>180 s) rectal balloon expulsion time. A principal components logistic model discriminated healthy people from patients with prolonged balloon expulsion time with 75% sensitivity and a specificity of 75%. Four phenotypes discriminated healthy people from patients with abnormal balloon expulsion times; 2 phenotypes discriminated healthy people from those with constipation but normal balloon expulsion time. Phenotypes were characterized based on high anal pressure at rest and during evacuation (high anal), low rectal pressure alone (low rectal) or low rectal pressure with impaired anal relaxation during evacuation (hybrid), and a short anal high-pressure zone. Symptoms were not useful for predicting which patients had prolonged balloon expulsion times.
Principal components analysis of rectoanal pressures identified 3 phenotypes (high anal, low rectal, and hybrid) that can discriminate among patients with normal and abnormal balloon expulsion time. These phenotypes might be useful to classify patients and increase our understanding of the pathogenesis of defecatory disorders.
排便障碍归因于盆底功能障碍。然而，临床观察表明存在一系列肛肠功能障碍。这些障碍的区别或重叠程度尚不清楚；肛肠测压法可用于诊断，但健康人在模拟排便时也可能存在直肠肛门压力梯度异常。我们旨在通过高分辨率肛肠测压法来描述便秘患者的表型变异。
我们评估了 62 名健康女性和 295 名慢性便秘女性的肛肠压力，采用高分辨率肛肠测压法测量，并测量直肠球囊排空时间。采用主成分分析对高分辨率肛肠测压法进行表型特征分析。
2 名健康人和 71 名患者的直肠球囊排空时间延长（>180s）。主成分逻辑模型以 75%的敏感性和 75%的特异性将健康人与排空时间延长的患者区分开来。4 种表型将健康人与排空时间异常的患者区分开来；2 种表型将健康人与排空时间正常但有便秘的患者区分开来。表型基于静息和排空时高肛门压力（高肛门）、单独低直肠压力（低直肠）或排空时直肠压力低伴肛门松弛受损（混合）以及短肛门高压区来确定。症状对于预测哪些患者排空时间延长并不有用。
直肠肛门压力的主成分分析确定了 3 种表型（高肛门、低直肠和混合），可区分排空时间正常和异常的患者。这些表型可能有助于对患者进行分类，并增加我们对排便障碍发病机制的理解。
