Effect of the dietary fiber glucomannan on chronic constipation in neurologically impaired children

Objective: Inadequate dietary fiber intake is a widely accepted explanation for chronic constipation in children with severe brain damage. The aim of our study was to evaluate the efficacy of glucomannan, a soluble fiber, as a treatment for chronic constipation in these children. Study design: Twenty children with severe brain damage and chronic constipa tion were randomly assigned to double-blind treatment with either glucomann an (n = 10) or placebo (n = 10) for 12 weeks. Stool habits, total and segme ntal gastrointestinal transit times, and anorectal motility were evaluated in all children before and after the treatment period. Results: Glucomannan significantly increased (P < .01) stool frequency, whe reas the effect of placebo was not significant. Laxative or suppository use was significantly reduced (P <.01) by glucomannan but was not affected by placebo. Clinical scores of stool consistency were significantly improved a nd episodes of painful defecation per week were significantly reduced by gl ucomannan (P < .01) but not by placebo. However, neither glucomannan nor pl acebo had a measurable effect on total and segmental transit times. Conclusions: In neurologically impaired children, glucomannan improves stoo l frequency but has no effect on colonic motility. (J Pediatr 2000;136: 41- 5).