British Dietetic Association Guidelines for the Dietary Management of Chronic Constipation in Adults

Current clinical guidelines for chronic constipation offer limited dietary recommendations. The aim of this project was to develop the first comprehensive evidence-based dietary guidelines for the management of chronic constipation in adults.

Four systematic reviews and meta-analyses were performed to identify eligible randomized controlled trials (RCTs). The findings generated from the meta-analyses were then used to develop guideline statements using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach and a Delphi consensus survey among a multidisciplinary expert Guideline Steering Committee. Recommendation statements were produced for treatment response, stool output, gut symptoms, adverse events, and quality of life, and only based on the findings where ≥ 2 RCTs contributed to the meta-analysis. The strength of recommendation was assessed using the GRADE approach. Consensus voting among the Guideline Steering Committee was performed using a modified Delphi survey approach.

The four systematic reviews included a total of 75 RCTs. Fifty-nine dietary recommendation statements were generated and accepted through the Delphi survey. For dietary supplements, 15 recommendation statements relate to fiber supplements, 20 relate to probiotics, two to synbiotics, five to magnesium oxide, two to senna, and three to kiwifruit supplements. For foods, three recommendation statements related to kiwifruits, two to prunes, and two to rye bread. For drinks, five recommendation statements related to high mineral-containing water. No recommendations were made for whole diet approaches due to lack of evidence. Twelve statements had a very low level of evidence, 39 had a low level of evidence, and eight had moderate evidence. Twenty-seven statements were strong recommendations, and 32 were qualified recommendations.

These are the first comprehensive evidence-based dietary guidelines for the management of constipation based upon a robust systematic review and GRADE processes. Recommendations were made for dietary supplements, foods, and drinks that have never been previously included in clinical guidelines, and can now be rapidly implemented into clinical practice, thereby improving clinical care and patient outcomes.