Prognosis of constipation: clinical factors and colonic transit time

Measurement of colonic transit time (CTT) is sometimes used in the evaluation of patients with chronic constipation.

To investigate the relation between symptoms and CTT, and to assess the importance of symptoms and CTT in predicting outcome.

Between 1995 and 2000, 169 consecutive patients (median age 8.4 years, 65% boys) fulfilling the criteria for constipation were enrolled. During the intervention and follow up period, all kept a diary to record symptoms. CTT was measured at entry to the study.

At entry, defecation frequency was lower in girls than in boys, while the frequency of encopresis episodes was higher in boys. CTT values were significantly higher in those with a low defecation frequency (< or =1/week) and a high frequency of encopresis (> or =2/day). However, 50% had CTT values within the normal range. Successful outcome occurred more often in those with a rectal impaction. CTT results <100 hours were not predictive of outcome. However, those with CTT >100 hours were less likely to have had a successful outcome.

The presence of a rectal impaction at presentation is associated with a better outcome at one year. A CTT >100 hours is associated with a poor outcome at one year.