Epidemiology and Mechanisms of Fecal Incontinence

大便失禁（FI）是老年妇女的一种社会破坏性症状，并可能导致机构。 “特发性”FI的流行病学和病理生理学尚不完全清楚。 基于三级护理研究的当前概念非常强调肛门内超声显示肛门括约肌缺损的作用。 初步研究表明，奥姆斯特德县50岁以上妇女的FI患病率为17.8%，发病年龄中位数为61岁。 产科事件、腹泻/尿急和肥胖是FI的风险因素。 我们新颖的“荧光透视”单次快速自旋回波MRI技术实时显示排便过程中的骨盆底下降。与超声相反，肛门内MRI显示外括约肌缺损和萎缩，耻骨直肠肌变薄和整体骨盆底松弛。 该假说认为，大便失禁并不是单独由产科创伤引起的，而是由产科创伤、过度紧张、肥胖、衰老和绝经引起的骨盆底虚弱的累积结果，并伴有腹泻。该假设将通过结合罗切斯特流行病学项目的数据基础设施与基于社区的样本中最先进的生理测量来解决。 将向之前接受调查的约1，000名妇女的队列邮寄问卷，以确定FI的发病率和自然史，并将对5，000名妇女进行新的抽样，以确定FI的患病率和频率。 将在一项病例对照研究中评价盆底损伤（产科创伤、慢性劳损、肥胖和雌激素耗竭）和FI（腹泻和直肠尿急）的推定风险因素，该研究包括约200例FI患者（至少每月一次）和约200例对照。大约100名FI患者和大约100名对照将进行MRI荧光透视以表征特定的整体骨盆底异常（即，肛门括约肌缺损、括约肌萎缩、耻骨直肠肌变薄和骨盆底松弛）。 这些研究将完善我们对FI流行病学的理解，确定导致盆底损伤（即FI）延迟表现的产科风险因素，强调非产科风险因素对FI的重要性，并为社区中与FI相关的盆底损伤的特定模式提供新的见解。 这些步骤对于通过风险因素修正降低盆底损伤的发生率，识别进展为症状性FI的风险较高的患者，以及设计适当的干预措施来阻止这一过程是必要的。

Fecal incontinence (FI) is a socially devastating symptom in older women and may contribute to institutionalization. The epidemiology and pathophysiology of "idiopathic" FI is incompletely understood. Current concepts based on tertiary-care studies heavily emphasize the role of anal sphincter defects visualized by endoanal ultrasound. Preliminary studies suggest that the prevalence of FI in Olmsted County in women greater than or equal to 50 years is 17.8 percent with a median age of onset of 61 years. Obstetric events, diarrhea/urgency and obesity are risk factors for FI. Our novel "fluoroscopic" single-shot fast spin-echo MRI techniques visualize pelvic floor descent during defecation in real-time. In contrast to US, endoanal MRI depicts external sphincter defects and atrophy, puborectalis thinning and global pelvic floor laxity. The hypothesis is that fecal incontinence is not attributable to obstetric trauma alone, but the cumulative result of pelvic floor weakness caused by obstetric trauma, excessive straining, obesity, aging and menopause, compounded by diarrhea. This hypothesis will be addressed by combining the data infrastructure of the Rochester Epidemiology Project with state- of-the-art physiological measurements in a community-based sample. A questionnaire will be mailed to a cohort of approximately 1,000 women surveyed previously to ascertain the incidence and natural history of FI, and, a new sample of 5,000 women to determine the prevalence and frequency of FI. Putative risk factors for pelvic floor injury (obstetric trauma, chronic straining, obesity and estrogen depletion) and FI (diarrhea and rectal urgency) will be evaluated in a case-control study of approximately 200 patients with FI at least once a month and approximately 200 controls. approximately 100 patients with FI and approximately 100 controls will have MRI fluoroscopy to characterize the specific global pelvic floor abnormality (i.e., anal sphincter defects, sphincter atrophy, puborectalis thinning and pelvic floor laxity) associated with FI. These studies will refine our understanding of the epidemiology of FI, identify the obstetric risk factors responsible for delayed manifestations of pelvic floor injury, i.e. FI, underscore the importance of non- obstetric risk factors for FI and provide novel insights into the specific pattern of pelvic floor injury associated with FI in a community. These steps are necessary for reducing the incidence of pelvic floor damage by risk factor modification, identifying patients at higher risk of progressing to symptomatic FI, and designing appropriate interventions to halt this process.