Guthrie E, Creed F, Fernandes L, Ratcliffe J, Van Der Jagt J, Martin J, Howlett S, Read N, Barlow J, Thompson D, Tomenson B
University of Manchester School of Psychiatry and Behavioural Science, Manchester, UK.
Gut. 2003 Nov;52(11):1616-22. doi: 10.1136/gut.52.11.1616.
Irritable bowel syndrome (IBS) is a heterogeneous condition which is diagnosed according to specific bowel symptom clusters. The aim of the present study was to identify subgroups of IBS subjects using measures of rectal sensitivity and psychological symptoms, in addition to bowel symptoms. Such groupings, which cross conventional diagnostic approaches, may provide greater understanding of the pathogenesis of the condition and its treatment.
A K means cluster analysis was used to group 107 clinic patients with IBS according to physiological, physical, and psychological parameters. All patients had severe IBS and had failed to respond to usual medical treatment. Twenty nine patients had diarrhoea predominant IBS, 26 constipation predominant, and 52 had an alternating bowel habit.
The clusters were most clearly delineated by two variables: "rectal perceptual threshold (volume)" and "number of doctor visits". Three subgroups were formed. Group I comprised patients with low distension thresholds and high rates of psychiatric morbidity, doctor consultations, interpersonal problems, and sexual abuse. Group II also had low distension thresholds but low rates of childhood abuse and moderate levels of psychiatric disorders. Group III had high distension thresholds, constipation or alternating IBS, and low rates of medical consultations and sexual abuse.
The marked differences across the three groups suggest that each may have a different pathogenesis and respond to different treatment approaches. Inclusion of psychosocial factors in the analysis enabled more clinically meaningful groups to be identified than those traditionally determined by bowel symptoms alone or rectal threshold.
肠易激综合征（IBS）是一种异质性疾病，根据特定的肠道症状群进行诊断。本研究的目的是除肠道症状外，利用直肠敏感性和心理症状指标来识别IBS患者的亚组。这种跨越传统诊断方法的分组可能会加深对该疾病发病机制及其治疗的理解。
采用K均值聚类分析，根据生理、身体和心理参数对107例临床IBS患者进行分组。所有患者均患有严重的IBS且对常规治疗无反应。29例患者以腹泻型IBS为主，26例以便秘型为主，52例有交替性排便习惯。
聚类最明显地由两个变量界定：“直肠感知阈值（容量）”和“就诊次数”。形成了三个亚组。第一组患者的扩张阈值低，精神疾病发病率、医生会诊次数、人际问题和性虐待发生率高。第二组患者的扩张阈值也低，但儿童期虐待发生率低，精神障碍水平中等。第三组患者扩张阈值高，患有便秘型或交替性IBS，医疗会诊次数和性虐待发生率低。
三组之间的显著差异表明，每组可能具有不同的发病机制，对不同的治疗方法有不同反应。与仅根据肠道症状或直肠阈值传统确定的分组相比，在分析中纳入社会心理因素能够识别出更具临床意义的分组。
