Background: Slow-transit constipation may be part of a pan-enteric motor disorder. To test this hypothesis 24-h ambulatory antroduodenal manometry was performed and orocaecal transit time determined in patients with slow-transit constipation and in healthy controls.

Methods: Antroduodenal motility was recorded with a five-channel solid-state catheter. Postprandial motility was recorded after consumption of two standardized test meals and interdigestive motility was recorded nocturnally. Manometry tracings were analysed for quantitative and qualitative abnormalities. Orocaecal transit time was determined by means of the lactulose hydrogen breath test.

Results: Postprandial motility was no different between patients and controls. However, some minor changes of interdigestive motility were observed. The proportion of phase II activity of the nocturnal cycles of the interdigestive migrating motor complex was increased in patients while phase I activity was decreased. The total number of observed phase III fronts was no different in patients and controls, although the number of phase III fronts with antral onset was decreased. Furthermore, the amplitude of phase III activity of duodenal onset was also decreased. Specific motor abnormalities such as retrograde propagation of phase III fronts were more frequent in patients. Orocaecal transit time was delayed in patients.

Conclusion: In patients with slow-transit constipation, orocaecal transit time is delayed but antro- duodenal motility is generally well preserved with only minor alterations. Presented as a poster to the Digestive Disease Week meeting in New Orleans, Louisiana, USA, May 1998, and published in abstract form as Gastroenterology 1998; 114: A820