Bulking Agent May Help Fecal Incontinence

March 16, 2011 -- It is a common, life-altering medical condition, but you aren’t likely to see a celebrity taking up the cause or a telethon devoted to finding a cure.

More than 5 million Americans have some degree of fecal incontinence. And many suffer in silence because they are too embarrassed to seek medical help.

As is the case with urinary incontinence, injections of a bulking agent are sometimes used to treat patients with moderate to severe bowel leakage, but the benefits of this therapy have not been proven.

Now a new study, to be published Friday in The Lancet, does appear to show a benefit for the therapy when compared to sham treatment.

But an expert who spoke to WebMD is not so certain.

Christine Norton, PhD, RN, who founded the UK Continence Foundation, was the lead author of a recent analysis concluding that there is not enough clinical evidence to recommend bulking agent injections for the treatment of fecal leakage.

She says the new study, while well done, does not tip the balance in favor of the treatment.

Bulking Agents for Fecal Incontinence

Fecal incontinence can range from occasional leakage of a small amount of stool while passing gas to a complete loss of bowel control.

Damage to the anal sphincter muscles as a result of childbirth, anal surgery, or other issues is a common cause of fecal incontinence, as are pelvic floor muscle weakness, constipation, and diarrhea, Norton says.

“Fecal incontinence really is the last taboo subject,” she tells WebMD. “Most people are just too embarrassed to talk about it, and many never discuss it with their doctors.”

As many as 15% of people in their 70s and older and 3% of people in their 20s have occasional to frequent fecal incontinence.

In the newly published study, 136 patients received four anal injections of the bulking compound dextranomer in stabilized hyaluronic acid (NASHA Dx), which is also used to treat urinary incontinence, while 70 patients got sham injections that did not include the compound.

The study was funded by medical device company Q-Med AB, which markets NASHA Dx for urinary incontinence.

Six months later, 52% of study participants treated with the bulking agent who completed the trial had a 50% or more reduction in incontinence episodes, compared to 31% of participants who got the sham treatment.

The median number of incontinence episodes over a two-week period declined by more than half in the active treatment group over a year of follow up -- from 15 before treatment to six after treatment.

Side Effects

The adverse event rate was higher in the active treatment group, and two serious abscess-related events were reported in these patients. Fourteen percent of patients in the active treatment group reported painful rectal spasms, compared to 3% of people in the sham treatment group.

Study researcher Wilhelm Graf, PhD, of Sweden’s Uppsala University Hospital tells WebMD that the findings prove that bulking agent injections can be an effective treatment for patients with moderate fecal incontinence.

In an editorial published with the study, Norton points out that Graf and colleagues offer no explanation for why NASHA Dx appeared to be more effective than other bulking agents used for fecal incontinence.

She also faulted the study for not including data on patient satisfaction.

“Patients who are leaking twice a day and have a 50% improvement may not feel their quality of life has improved all that much,” Norton says. “They are still wearing a diaper and still worried about where the toilets are when they go out. In my experience with these patients, anything short of a cure is a disappointment.”