Fecal incontinence

Fecal incontinence, an involuntary passing of stool, affects 45-50% of nursing home residents.

1-3 Dual incontinence (both fecal and urinary) is the second most common reason an elderly individual is institutionalized.

4 Nursing home residents who are incontinent have more urinary tract infections

4 and persons with fecal incontinence have a 22% greater chance of developing pressure ulcers.

5

Risk factors for fecal incontinence include: fecal impaction; loss of normal continence mechanisms due to local neuronal damage; impaired neurological control or anorectal trauma/sphincter disruption; conditions overwhelming the normal continence mechanism such as laxative use, diarrhea, colitis, or radiation; behavioral or psychological problems such as delirium, dementia, or severe depression; functional impairment related to hemiplegia or hemiparesis, impaired gait or arthritis; and, in rare cases, neoplasm. Although fecal incontinence is rarely related to a single factor,6 constipation and diarrhea are the most common causes of fecal incontinence. The elderly incontinent person has less rectal sensation and less sphincter strength than the person who is not incontinent.7

History and physical

An evaluation for fecal incontinence should include a history including when symptoms first started; history of previous surgeries, obstetrical injury, or radiation; existence of colitis; and a thorough review of prescription and over-the counter medications (see Tables 1 and 2). Patients who receive liquid medications orally or via feeding tube should be evaluated for the amount of sorbital they are ingesting as this is a common component of liquid medications. New onset fecal incontinence may be indicative of spinal cord compression, particularly if the patient has other neurological symptoms.

Table 1. Medications associated with constipation

Examination and testing

A physical examination should follow the history and should include a neurological exam, including testing for the presence or absence of the “anal wink.” The absence of this reflex indicates neural damage. The perineum should be examined for abnormalities and a digital rectal exam should be performed. Following the physical exam, diagnostic tests may be indicated. Since fecal impaction is a primary reason for fecal incontinence in the elderly, a plain radiograph is indicated to rule out an impaction. Flexible sigmoidoscopy, colonoscopy, anal manometry, electromyography, anal ultrasound, and magnetic resonance imaging are additional diagnostic tests that may be indicated (see Table 3).

Treatment

Treatment of fecal incontinence hinges on underlying etiology and severity of incontinence. Conservative therapy includes habit training (timed defecation), use of antidiarrheal agents if stool is too loose, and biofeedback. Loperamide is an effective antidiarrheal agent and is better tolerated by the elderly than alternatives such as diphenoxylate or codeine. Multiple studies have validated the effectiveness of biofeedback in treatment of fecal incontinence, leading to improvement in symptoms for at least 50% of patients. Motivated, cognitively intact patients have the best outcomes.4