Fecal Incontinence: Risk Factors

Fecal incontinence is not considered a normal part of aging. And, for many people with fecal incontinence, there may be more than one cause to consider and manage. There are two main categories of fecal incontinence including urge incontinence and passive incontinence. Urge incontinence is defined as feeling an urge and being unable to get to a toilet in time before leakage. Passive incontinence is when sensations that indicate the need to defecate are not adequately felt and subsequently leakage occurs.  

Types: urge and passive Age and gender factors Diarrhea, constipation Muscle and/or nerve damage Rectal prolapse, rectocele Physical inactivity and/or disability Cognitive deficit: passive incontinence

Fecal incontinence is more common in adults who are 65 years of age or older. Females may be at higher risk for fecal incontinence. This is often related to childbirth. There is also a modest increased risk for menopausal women who take hormone replacement therapy.

Because solid stool is easier to hold in the rectum, diarrhea and loose stools can both cause and worsen fecal incontinence. Constipation can cause a stool that becomes too large to pass, which is known as impaction. This causes the muscles of the rectum and intestines to stretch and weaken. Watery stool from farther up the digestive tract may move around the impacted stool and result in stool leakage.

Long-lasting constipation can lead to nerve damage, which predisposes to fecal incontinence. Constipation can cause a stool that becomes too large to pass, which is known as impaction. This causes the muscles of the rectum and intestines to stretch and weaken. Watery stool from farther up the digestive tract may move around the impacted stool and result in stool leakage. Long-lasting constipation can lead to nerve damage, which predisposes to fecal incontinence.

Hemorrhoids, which are swollen veins in the rectum, can prevent the anus from completely closing and allow stool leakage. Also, gall bladder removal may be a risk factor for the development of fecal incontinence.

Damage to the rectum that results in scarring or stiffness can happen in cases of surgery, radiation treatment, or inflammatory bowel disease. This may limit the ability of the rectum to stretch to accommodate stool and excess amounts may leak.

Muscle damage, such as injury to the rings of muscle at the end of the rectum known as the anal sphincter, cause difficulty in holding in a stool. Damage to this area may happen to women during childbirth, particularly with episiotomy or using forceps during delivery.

Injury to nerves that sense stool in the rectum or that control the anal sphincter can lead to fecal incontinence. Nerve damage can happen for a number of reasons, including childbirth, repeated straining during defecation, long-lasting constipation, and conditions that have a nerve component, such as stroke, diabetes, multiple sclerosis, and spinal cord injury. In addition, surgeries that involve the rectum and anus (such as removal of hemorrhoids) can lead to nerve damage.

Rectal prolapse is when the rectum drops into the anus and causes the trenching and damage to nerves that control the rectal sphincter. Time is of the essence for treatment, because the longer this condition lasts, recovery of nerves and muscle control diminishes. In women, rectocele or the rectum protruding through the vagina can lead to fecal incontinence.

Patients who are not physically active are at higher risk for fecal incontinence. Physical disabilities and cognitive deficits may increase the difficulty in reaching a toilet in time and properly toileting. For instance, fecal incontinence is common in late-stage Alzheimer’s disease.

In general, fecal incontinence may occur in 7% to 15% of adults who are not in institutional settings. Prevalence rises to 18% to 33% in the hospital setting and to between 50% and 70% for nursing home settings.

 

Fecal Incontinence: Diagnosis

Patients can be educated and learn the risks and indicators of fecal incontinence. Patients and caregivers should understand when it is important to discuss the possibility of fecal incontinence with their health care team.

Medical history   Physical examination Digital rectal examination Balloon expulsion test Anal manometry   Medical tests: Ultrasound, proctography, colonoscopy, MRI

Evaluation of the fecal incontinence condition requires accurate responses from patients, which can be assisted by a stool diary that can document frequency, consistency, precipitating events, and other factors. This type of evaluation has been shown to be a better source of information than questionnaires that patients might complete. Rectal examination is important to conduct, but should be conducted in a respectful way with the patient.

A digital rectal exam can be used to evaluate the strength of the sphincter muscles and check for abnormalities in the rectal area. Asking the patient to bear down during this exam can help to check for rectal prolapse.

A balloon expulsion test involves inserting a small balloon filled with water into the rectum and toileting to expel the balloon. If it takes longer than one to three minutes to accomplished this, there may be a defecation disorder. Anal manometry involves a flexible narrow tube inserted into the anus and rectum with a small balloon at the tip that can be expanded to measure anal sphincter tightness, sensitivity, and function of the rectum. Ultrasounds of the anorectal area provide video images to check the structure of the anal sphincter. X-ray video images, called proctography, can be made during a bowel movement on a specially designed toilet to measure how much stool the rectum can hold and how well the stool is expelled. Colonoscopy tests can examine the entire colon and can help to identify signs of inflammation and digestive tract issues. And, magnetic resonance imaging or MRI can provide clear evaluation of the sphincter and determination of intact muscles. This type of technology can be used during bowel movements and is called defecography.