Trial Report Randomized double-blind placebo-controlled study to evaluate the effect of long-acting mesalamine on postinfectious IBS with diarrhea, 2024, Tuteja

Tuteja AK, Leung DT, Fang JC, Talley NJ, Stoddard GJ. Randomized double-blind placebo-controlled study to evaluate the effect of long-acting mesalamine on postinfectious irritable bowel syndrome with diarrhea. Neurogastroenterology & Motility. 2024; 00:e14889. doi:10.1111/nmo.14889

https://onlinelibrary.wiley.com/doi/10.1111/nmo.14889

ORIGINAL ARTICLE
Open Access
Randomized double-blind placebo-controlled study to evaluate the effect of long-acting mesalamine on postinfectious irritable bowel syndrome with diarrhea

Ashok K. Tuteja, Daniel T. Leung, John C. Fang, Nicholas. J. Talley, Gregory J. Stoddard
First published: 05 August 2024

https://doi.org/10.1111/nmo.14889



Abstract
Background
A subset of patients with irritable bowel syndrome (IBS) develop their symptoms after gastroenteritis, referred to as postinfectious IBS (PI-IBS). PI-IBS is associated with low-grade intestinal inflammation. Previous studies have evaluated mesalamine, an anti-inflammatory drug, in patients with IBS. We evaluated the efficacy of long-acting mesalamine in patients with PI-IBS.

Methods
Sixty-one patients who developed diarrhea-predominant IBS (IBS-D) after gastroenteritis were randomized to receive either 2.4 g of long-acting mesalamine or placebo daily for 8-weeks. The symptoms assessed were abdominal pain, bloating, stool frequency, stool consistency, severity of diarrhea and constipation, satisfaction with bowel habits, and IBS affecting or interfering with life. Quality-of-life (QOL) was assessed using the IBS-QOL questionnaire. The prespecified primary outcome variable was the overall bowel symptom score (BSS) after 8-weeks of treatment. Effect sizes were expressed as standardized mean differences (Cohen's d).

Results
Fifty-four patients completed the 8-week treatment (n = 28 mesalamine, n = 26 placebo), 49 (91%) were male, and age range 23–71 years (mean ± SD 43 ± 13). Mesalamine demonstrated superior efficacy compared to placebo on the primary outcome variable, overall BSS (Cohen's d = 0.57, p = 0.042). Mesalamine was also superior for the secondary outcome of how much IBS affects your life in general (d = 0.72, p = 0.01). For the secondary outcomes of IBS symptoms, 7 of the 7 symptoms had trends of mesalamine superiority. For the secondary outcomes of IBS-QOL subscales, 8 of 9 had trends of mesalamine superiority.

Conclusion
In patients with PI-IBS, long-acting mesalamine demonstrated to be effective in reducing IBS symptoms and improving QOL.


Key points

• A subset of patients with irritable bowel syndrome (IBS) develop their symptoms after gastroenteritis, labeled post-infectious IBS (PI-IBS). PI-IBS is associated with low-grade inflammation. Mesalamine is an anti-inflammatory drug used in the treatment of inflammatory bowel disease. We evaluated the efficacy of long-acting mesalamine in patients with PI-IBS with diarrhea.
• Mesalamine significantly improved IBS symptoms as measured with the overall IBS symptom score, and there was a trend towards improvement in all symptoms of IBS and in quality of life. Mesalamine was well tolerated with no serious adverse effects.
• Mesalamine may have a role in the treatment of PI-IBS with diarrhea.