Effect of glucomannan on functional constipation in children: a systematic review and meta-analysis of randomised controlled trials

Asia Pac J Clin Nutr. 2017 May;26(3):471-477. doi: 10.6133/apjcn.032016.03.

Abstract

Background and objectives: Constipation, a common complaint in children, considerably affects the quality of life. This systematic review assessed the treatment effects of glucomannan on children with constipation by summarising evidence from previous randomised controlled trials (RCTs).

Methods and study design: A comprehensive electronic literature search was conducted for identifying eligible RCTs that evaluated the effectiveness of glucomannan. The results were reported as mean differences (MDs), standardised mean differences (SMDs), and risk ratios (RRs) with 95% confidence intervals (CIs). The primary outcome was the defecation frequency per week; the secondary outcomes were stool consistency and the rate of successful treatment. A metaanalysis was conducted using the random effects model.

Results: Three RCTs evaluating 122 participants were identified. Glucomannan use was associated with an increased frequency of defecation (3 trials; MD=1.40; 95% CI: 0.36-2.44, p=0.008); however, there were no significant differences in the outcomes of stool consistency (3 trials; SMD=0.48; 95% CI: -0.44 to 1.40, p=0.300) or the rate of successful treatment (2 trials; RR=1.36; 95% CI: 0.48-3.81, p=0.110).

Conclusions: Glucomannan moderately increases the defecation frequency of children with constipation but is not associated with a reduction in stool consistency or overall improvement in the rate of successful treatment. However, these results should be cautiously interpreted because of the small sample size and the risk of products containing glucomannan need to be considered. Additional large-scale and well-designed RCTs are necessary to evaluate the efficacy and long-term safety of glucomannan.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Child
  • Constipation / drug therapy*
  • Defecation / drug effects
  • Dietary Fiber / administration & dosage*
  • Humans
  • Mannans / therapeutic use*
  • Quality of Life
  • Randomized Controlled Trials as Topic
  • Treatment Outcome

Substances

  • Dietary Fiber
  • Mannans
  • (1-6)-alpha-glucomannan