aCentre for Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge bDepartment of Medicine, Karolinska Institutet, Solna cCentre for Gastrointestinal Disease, Sabbatsberg Hospital dStress Research Institute, Stockholm University, Stockholm, Sweden eFaculty of Health, University of Newcastle, Callaghan, New South Wales, Australia.
Eur J Gastroenterol Hepatol. 2014 Mar;26(3):268-75. doi: 10.1097/MEG.0000000000000024.
To analyse the epidemiology of irritable bowel syndrome (IBS) symptoms in a random sample of the general population and in a subsample consenting to a colonoscopy, and to what extent this introduces symptom selection bias.
Overall, 3347 randomly selected Swedish adults aged 18-70 years were mailed the validated Abdominal Symptom Questionnaire (ASQ). Responders (n=2293; 68.5%) were contacted by phone, and 745 consented to a colonoscopy. All nonresponders were contacted by phone; 265 were reached and asked seven key ASQ questions. Colonoscopy participants also completed the Rome II Modular Questionnaire.
The prevalence of IBS on the basis of the mailed ASQ (troublesome abdominal pain and bowel disturbance in the past 3 months) was 26.2% [95% confidence interval (CI): 24.4-28.0] among the ASQ responders and 36.6% (95% CI: 33.2-40.1) among the colonoscopy participants (P<0.001). Nonresponders had a lower prevalence of IBS (15.8%; 95% CI: 11.4-20.3, P<0.001) than ASQ responders. Colonoscopy participants were slightly older than noncolonoscoped participants completing the ASQ (P<0.001), but men and women were equally represented and no significant socioeconomic differences were identified. The prevalence of IBS was 14.8% (95% CI: 12.2-17.5) on the basis of the Rome II Modular Questionnaire in colonoscopy participants and 14.5% (95% CI: 11.9-17.2) when visible inflammatory disease was excluded. Of the colonoscopy participants, 31.9% (95% CI: 28.5-35.3) were symptom free.
IBS symptoms are common and rarely explained by visible inflammatory disease or cancer. There was a modest selection bias by IBS in participants accepting a screening colonoscopy, but still, one-third were symptom free. Thus, conclusions for the general population can be made from findings in the study cohort.
分析普通人群随机样本和同意结肠镜检查的亚组中肠易激综合征（IBS）症状的流行病学，并分析其在多大程度上引入了症状选择偏倚。
总共对 3347 名年龄在 18-70 岁的瑞典成年人进行了随机抽样，邮寄了经过验证的腹部症状问卷（ASQ）。对 2293 名应答者（68.5%）进行了电话联系，其中 745 人同意进行结肠镜检查。所有未应答者均通过电话联系；联系到 265 人，并询问了 ASQ 的七个关键问题。结肠镜检查参与者还完成了罗马 II 模块问卷。
根据邮寄的 ASQ（过去 3 个月内出现腹部不适和肠功能紊乱），ASQ 应答者中 IBS 的患病率为 26.2%（95%置信区间：24.4-28.0），结肠镜检查参与者中为 36.6%（95%置信区间：33.2-40.1）（P<0.001）。未应答者的 IBS 患病率较低（15.8%；95%置信区间：11.4-20.3，P<0.001），低于 ASQ 应答者。接受 ASQ 检查的结肠镜检查参与者比未接受结肠镜检查的参与者稍年长（P<0.001），但男女比例相等，且没有明显的社会经济差异。在结肠镜检查参与者中，根据罗马 II 模块问卷，IBS 的患病率为 14.8%（95%置信区间：12.2-17.5），当排除可见炎症性疾病时，IBS 的患病率为 14.5%（95%置信区间：11.9-17.2）。在结肠镜检查参与者中，31.9%（95%置信区间：28.5-35.3）无症状。
IBS 症状很常见，很少由可见的炎症性疾病或癌症解释。在接受筛查性结肠镜检查的参与者中，IBS 存在适度的选择偏倚，但仍有三分之一的人无症状。因此，可以从研究队列的发现中得出对一般人群的结论。
