Diagnosis and Management of Fecal Incontinence

Abstract

DEFINITION Fecal incontinence is defined as either the involuntary passage or the inability to control the discharge of fecal matter through the anus. Clinically there are three subtypes (a) passive incontinence—the involuntary discharge of stool or gas without awareness; (b) urge incontinence—the discharge of fecal matter in spite of active attempts to retain bowel contents, and (c) fecal seepage—the leakage of stool following otherwise normal evacuation. The severity of incontinence can range from the unintentional elimination of flatus to the seepage of liquid fecal matter or sometimes the complete evacuation of bowel contents. Not surprisingly, these events cause considerable embarrassment, which in turn can lead to a loss of self-esteem, social isolation, and a diminished quality of life (1). EPIDEMIOLOGY Although fecal incontinence affects people of all ages, its prevalence is disproportionally higher in women, in the elderly, and in nursing home residents. Estimates of its prevalence vary greatly and depend on the clinical setting, the influence of social stigma, the definition of incontinence, and the frequency of occurrence. In the U.S. householder survey, frequent leakage of stool or fecal staining for more than 1 month was reported by 7.1% and 0.7% of the population, respectively (2). In contrast, two or more episodes of fecal incontinence per month were reported by 0.8% of patients presenting to primary care clinics in the UK (3). In an elderly (>65 yr) self-caring population, fecal incontinence occurred at least once a week in 3.7% of subjects and in more men than women (men:women = 1.5:1) (4). In contrast, 25–35% of institutionalized patients (5) and 10–25% of hospitalized geriatric patients (6) suffer from fecal incontinence. In the United States, fecal incontinence is the second leading cause for placement in nursing homes (6). In a survey of 2,570 households, comprising 6,959 individuals, the prevalence of at least one episode of incontinence during the previous year was 2.2%; among these 63% were women, 30% were >65 yr of age, 36% were incontinent of solid stool, 54% of liquid stool, and 60% of flatus (7). Furthermore, in another prospective survey of patients attending either a gastroenterology or a primary care clinic, over 18% reported fecal incontinence at least once a week (8). Only one third had ever discussed the problem with a physician (8). When stratified for the frequency of episodes, 2.7% of patients reported daily incontinence, 4.5% weekly, and 7.1% once per month (8). In another survey, fecal incontinence was associated with urinary incontinence in 26% of women attending a Uro/Gyn Clinic (9). A higher incidence of mixed fecal and urinary incontinence was also reported in nursing home residents (10, 11). The cost of health care related to fecal incontinence includes items that can be measured such as the evaluation, diagnosis and treatment of incontinence, medications, the use of disposable pads and other ancillary devices, skin care, and nursing care. Approximately $400 million/year were spent for adult diapers (8, 12) and between $1.5 and $7 billion/year were spent on care for incontinence among institutionalized elderly patients (6, 13). In a long-term facility, the annual cost for a patient with both mixed fecal and urinary incontinence was $9,711 (14). In the outpatient setting, the average cost per patient (including evaluation) was estimated at $17,166 (15). Additionally, there are other costs that cannot be measured such as the impaired quality of life and social dysfunction (1). SUMMARY. The prevalence of fecal incontinence ranges between 1% and 7.4% in otherwise healthy people and up to 25% in those who are institutionalized. Both the embarrassment and the social stigma attached to this disorder, often delay presentation as well as treatment for several years. Fecal incontinence not only causes significant morbidity in the community but it also consumes substantial health care resources. PATHOPHYSIOLOGY Functional Anatomy and Physiology of the Anorectum The neuromuscular integrity of the rectum, anus, and the adjoining pelvic floor musculature helps to maintain normal fecal continence. The rectum is a muscular tube composed of a continuous layer of longitudinal muscle that interlaces with the underlying circular muscle. This unique muscle arrangement enables the rectum to serve both as a reservoir for stool and as a pump for emptying stool. The anus is a muscular tube 2–4 cm. long, which at rest forms an angle with the axis of the rectum. At rest, the anorectal angle is approximately 90 degrees, with voluntary squeeze it becomes more acute, approximately 70 degrees, and during defecation it becomes more obtuse, about 110–130 degrees. The anal sphincter consists of the internal anal sphincter, which is a 0.3–0.5 cm thick expansion of the circular smooth muscle layer of the rectum, and the anal sphincter which is a cm thick expansion of the both are and The anus is by