PHILADELPHIA—Biofeedback and dextranomer/hyaluronic acid injection show similar efficacy in the treatment of fecal incontinence, with many patients experiencing substantial improvement of FI symptoms at three months.

“Anorectal bowel feedback therapy is typically reserved for patients who don’t respond to conservative measures, followed by intra-anal injection of dextranomer or, infrequently, sacral nerve simulation,” said Adil E. Bharucha, MD, a professor of medicine at Mayo Clinic in Rochester, Minn., presenting the study at ACG 2024. “Unfortunately, there’s limited evidence to support the effectiveness of these approaches and few comparative trials.”

To compare the effectiveness of biofeedback therapy with dextranomer injections in patients with FI who had failed enhanced medical management (EMM) delivered rigorously with bowel agents and pelvic floor exercises, Dr. Bharucha and his co-investigators enrolled adults with at least six months of FI twice weekly or more in a multicenter, randomized trial.

Further enrollment criteria included being able to ambulate independently. Patients were excluded if they had cognitive impairment, a recent third-degree sphincter tear, fecal impaction or one of an array of comorbidities, such as inflammatory bowel disease or spinal cord injury.

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The participants were mostly women in their 60s, “similar to the patients we see in our practices. They had more than one episode of incontinence a day, and their severity scores indicated moderately severe symptoms that had a considerable impact on the quality of life [QOL],” Dr. Bharucha said.

The study started with a two-week baseline period, after which patients who had four or more episodes of FI proceeded to the EMM phase. Responders, defined as having a 75% or greater reduction in FI, are being followed for up to two years, and nonresponders were randomized to biofeedback or injection.

“Nonresponders to biofeedback or dextranomer at three months had an opportunity to choose the alternative treatment of sacral nerve stimulation, and, as in clinical practice, patients who received dextranomer had the option to receive a second injection,” Dr. Bharucha said.

The primary outcome was a 75% or more reduction in FI frequency; secondary outcomes included a 50% reduction in FI, change in FI score and FI QOL score. “All analyses were adjusted for sex and site of enrollment,” he added.

Of the 275 patients enrolled in the EMM program, 259 completed it and 39 (15%) responded to EMM. The 220 (80%) nonresponders were randomized to injection or biofeedback therapy.

Approximately 30% of patients achieved the primary efficacy outcome of a 75% reduction in FI, regardless of treatment, and about 50% achieved the secondary outcome of a 50% reduction in FI, again, regardless of treatment.

The FI severity score declined in both groups, reflecting less severe symptoms, “more so for biofeedback than injection, but the differences were not significant,” Dr. Bharucha said. “The QOL for all four domains increased with both treatments, and differences between groups were not significant.”

Based on the findings, Dr. Bharucha said, “we feel both treatments should be considered in FI patients who have failed conservative methods.”

Dr. Barucha concluded his presentation with a note of appreciation “for the patients who suffer, often in silence, who graciously participated in this study with a remarkable gratitude of spirit.”

Amy Oxentenko, MD, a gastroenterologist and professor of medicine at Mayo Clinic in Rochester, who co-moderated the session in which Dr. Bharucha presented the study, inquired whether investigators observed any factors that were predictive of successful response to therapy. “In this study or anecdotally, do you have a sense whether patients respond better to one therapy or the other depending on the cause of their FI, whether it was traumatic, through obstetric or other surgical trauma, versus general weakness or neuromuscular dysfunction?” she asked.

Dr. Bharucha responded that conceptually, a dextranomer injection, which is designed to restore the anal barrier, may be more effective for patients who have a weak anal resting pressure, while biofeedback therapy arguably is more likely to improve external sphincter (skeletal muscle) dysfunction, which is often associated with FI. “However,” he added, “there are no data to support this concept, which will be evaluated with further analyses in this study.”

—Monica J. Smith

This article is from the March 2025 print issue.