Kurin M, Elangovan A, Alikhan MM, et al. - Findings demonstrate at least 4 times greater probability of developing a mast cell disorder (MCD) in irritable bowel syndrome (IBS) patients compared with the general population, in a large US database encompassing >53 million patients over >20 years.

• According to mounting evidence, there exists a mechanistic link between IBS symptoms and mast cell hyperactivity.

• Two large databases (IBM Watson Health Explorys database and Epic EHR) were used to include patients with IBS and MCDs.

• Manual chart review from two academic centers was performed to verify findings.

• A comorbid MCD was present in up to 4% of IBS patients.

• A strong association of IBS with all MCDs was evident, with the strongest link with mast cell activation syndrome (OR 16.3).

• For IBS+urticaria, IBS+idiopathic urticaria, IBS+non-malignant mastocytosis, and IBS+mast cell malignancy, the odds ratios ranged from 4.5 to 9.9.

• The overlap cohorts more commonly had thorough endoscopic evaluation and comorbid mood disorders and migraines, than IBS alone.