Effect of Polydextrose Intake on Constipation in Japanese Dialysis Patients: A Triple-Blind, Randomized, Controlled Trial

The objective of the present study was to evaluate bowel habits induced by ingestion of 10 g polydextrose (PDX) fed to Japanese hemodialysis (HD) patients. This was a randomized, placebo-controlled, triple-blind, parallel-group controlled, 8-wk study. A total of 50 HD outpatients capable of self-management (51-79 y of age) were recruited at H Clinic. Japan. Inclusion criteria for participation in the study were ingestion of one or more laxative tablets for more than 3 mo and having received HD for more than 6 mo. The participants were randomly assigned to 2 groups: A (0 g polydextrose/d: control), B (10 g polydextrose/d: PDX). The primary outcome measure was stool frequency. Secondary outcomes were stool consistency, abdominal pain, intestinal bloating and clinical biochemistry indexes. PDX had no significant effect on blood biochemistry indexes. The PDX group showed significant improvements in bowel function (stool frequency increased from 3.0 times per week to 7.5 times per week) and reported no laxation problems (abdominal distention, cramps, and diarrhea) (p<0.01). Regular consumption of the PDX products increased dietary fiber intake to recommended levels and improved bowel habits.