Effective Constipation Treatment Changes More Than Bowel Frequency: A Systematic Review and Meta-Analysis

Area of Science:

• Gastroenterology
• Clinical Pharmacology

Background:

• Newer medications for constipation and irritable bowel syndrome with constipation (IBS-C) highlight abdominal pain reduction.
• It remains unclear if this pain relief stems from specific drug effects or general laxation benefits.

Purpose of the Study:

• To investigate the relationship between improved bowel frequency and decreased abdominal pain in clinical trials for constipation and IBS-C.
• To determine if pain reduction is a general effect of effective laxation or a specific drug property.

Main Methods:

• A systematic literature search of "PubMed" and "Embase" was conducted for relevant clinical trials.
• Meta-analytic and meta-regression analyses were performed on data from 27 trials (16 constipation, 11 IBS-C).

Main Results:

• Treatments significantly increased weekly bowel movements (2.17 increase) and reduced pain ratings (0.58 decrease).
• Meta-regression revealed a significant correlation between increased bowel frequency and decreased pain.
• Baseline pain and bowel frequency were comparable between constipation and IBS-C groups.

Conclusions:

• Abdominal pain reduction in constipation and IBS-C trials is strongly associated with improved laxation.
• The findings suggest that effective laxation, rather than unique drug mechanisms, may be responsible for pain relief.
• This challenges the notion that newer agents offer a distinct advantage over traditional laxatives for pain management in these conditions.