Because the pathophysiologic basis of constipation remains unclear, the role of colonic dysfunction continues to be debated, and objective data, especially on colonic propulsive activity, are limited. As published in a recent issue of Digestion, Gabrio Bassotti, MD, PhD, and colleagues used 24-hour colonic manometric recordings to compare high- and low-amplitude colonic propulsive activity in constipated patients. The study compared colonic propulsive activity in 35 patients who had slow-transit constipation (STC) and 10 patients who had irritable bowel syndrome with constipation (IBS-C) with that in nonconstipated controls.
The investigators found that high-amplitude propagated contractions are significantly decreased in patients with STC and in patients with IBS-C, compared with those in controls. A significant decrease in contraction amplitude was also observed in patients with STC. With regard to low-amplitude propagated contractions, patients with STC had significantly fewer events, compared with patients with IBS-C.
The authors concluded that low-amplitude propagated contractions represent an important physiologic motor event in constipated patients. These contractions may preserve residual colonic propulsive activity in patients with STC.