Effect of biofeedback therapy on anorectal physiological parameters among patients with fecal evacuation disorder.

BACKGROUND: Though biofeedback therapy is often effective in patients with fecal evacuation disorder (FED), a common cause of chronic constipation (CC) in tertiary practice, data on anorectal physiological parameters following it are scanty.

METHODS: Consecutive patients with FED with CC diagnosed by abnormalities in at least two of the three tests (anorectal manometry, defecography, and balloon expulsion test [BET]) undergoing biofeedback (two sessions per day, 30 min each, for 2 weeks) during a 3-year period were analyzed. Clinical evaluation, anorectal manometry (ARM), and BET were performed at the beginning and after biofeedback.

RESULTS: Incomplete evacuation 42/43 (98%), straining 40/43 (93%), and feeling of outlet obstruction 35/43 (81%) were the most common symptoms among these 43 patients (median age 44 years, range 18-76, 30 [71%] male). All the three tests (defecography, BET, and ARM) were abnormal in 17 (40%) patients and the others had two abnormal tests. Improvement in physiological parameters was noted following biofeedback (median residual anal pressure during defecation 99 mmHg (range 52-148) vs. 78 mmHg (37-182), p = 0.03; maximum intra-rectal pressure 60 mmHg (90-110) vs. 76 mmHg (31-178); p = 0.01; defecation index 1.1 (0.1-23.0) vs. 3.2 (0.5-29.0); p = 0.001). Dyssynergia on ARM and BET got corrected in 22/34 (65%) and 18/30 (60%) patients. At a 1-month follow up, 23/37 (62%) patients reported satisfactory symptomatic improvement.

CONCLUSIONS: Biofeedback not only improves symptoms but also anorectal physiological parameters in patients with FED.