Decreased risk for microscopic colitis and inflammatory bowel disease among patients with reflux disease

Aim: Previous studies have found an increased risk for microscopic colitis (MC) associated with proton pump inhibitors. In patients with ulcerative colitis (UC) or Crohn's disease (CD), proton pump inhibitors have been associated with an increased risk for IBD flares and impaired outcomes. The aim of this study was to test the epidemiological associations between gastro-oesophageal reflux disease (GERD) and MC, UC or CD in a large database. Method: The Miraca Life Sciences Database is a national electronic repository of histopathological records of patients distributed throughout the entire USA. A case–control study evaluated whether the presence of Barrett's metaplasia, erosive oesophagitis on endoscopy or histological signs of reflux oesophagitis, clinical diagnosis of GERD or any GERD type affected the occurrence of MC, UC or CD among 228 506 subjects undergoing bidirectional endoscopy. Multivariate logistic regression analyses were used to calculate ORs and their 95% CI for the risk of MC, UC or CD associated with various types of GERD and were adjusted for age, sex and presence of Helicobacter pylori. Results: The analysis revealed an inverse relationship between GERD and different types of inflammatory bowel disease. The inverse relationships applied similarly to MC (mean = 0.62, 95% CI: 0.58–0.66), UC (mean = 0.89, 95% CI: 0.81–0.97) and CD (mean = 0.76, 95% CI: 0.69–0.85). It also applied to different forms of GERD, with a trend towards more pronounced inverse relationships associated with Barrett's metaplasia or erosive oesophagitis than clinical diagnosis of GERD. Conclusion: Gastro-oesophageal reflux disease is inversely associated with all forms of inflammatory bowel disease, such as MC, UC, or CD.