Prolonged ambulatory recording of anorectal motility in patients with slow-transit constipation

Our aim was to determine phasic contractile activity of the distal bowel and anus in patients with slow-transit constipation; if readily identifiable patterns were present, prolonged recordings could confirm a diagnosis of slow-transit constipation. In 12 healthy control subjects and 11 women patients with slow-transit constipation (mean colonic transit time: 120 +/- 11 hours) and normal pelvic floor function, a flexible catheter was positioned endoscopically with sensors in the sigmoid colon, rectum, and anal canal in order to perform ambulatory recordings. A motility index (MI = mm Hg/h/100) was calculated during fasting and after feeding. Overall, the rectal MI and the frequency of anal canal contractions were less in the patients with constipation compared with those in the control group (rectum: 22 +/- 5 mm Hg/h/100 in the control group versus 13 +/- 10 mm Hg/h/100 in the constipation group; anal contractions/h: 23 +/- 7 in the control group versus 3 +/- 2 in the constipation group, p < 0.05). Moreover, in response to feeding, only control subjects had a significantly increased MI and frequency of anal canal contractions. Compared with control subjects, patients with slow-transit constipation had significantly reduced motor activity in the distal bowel and anal canal. Phasic contractile activity recorded during fasting and in response to a meal may be a means of confirming the diagnosis of slow-transit constipation in patients with borderline marker transit times.