Environmental Pollutants are Associated with Irritable Bowel Syndrome in a Commercially Insured Cohort of California Residents. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Okafor, P. N., Dahlen, A., Youssef, M., Olayode, A., Sonu, I., Neshatian, L., Nguyen, L., Charu, V. 2022

Abstract

BACKGROUND AND AIMS: Prior studies have linked environmental pollutants with gastrointestinal (GI) diseases. Here, we quantify the relationships between seven pollutants and the zip code-level incidence of irritable bowel syndrome (IBS), functional dyspepsia (FD), inflammatory bowel diseases (IBD), and eosinophilic esophagitis (EoE) in California.METHODS: Claims in Optum's Clinformatics Data Mart (CDM) were linked with environmental exposures in California, derived from CalEnviroScreen 3.0. We identified adult patients with new diagnoses of each GI disease, and estimated claims-derived, zip-code level disease incidence rates. Two study periods were considered: 2009-2014 (ICD-9 era) and 2016-2019 (ICD-10 era). Multivariable negative binomial regression models were used to test associations between seven pollutants (ozone, particulate matter <2.5 microns [PM2.5], diesel emissions, drinking water contaminants, pesticides, toxic releases from industrial facilities, traffic density) and zip-code level incidence of the GI diseases along with a negative control outcome, adjusting for numerous potential confounders.RESULTS: Zip code-level IBS incidence was associated with PM2.5 (p<0.001 in both eras) and airborne toxic releases from facilities (p<0.001 in both eras). An increase of 1 microgram/m3 in PM2.5 or 1% in toxic releases translates to an increase in the IBS incidence rate of about 0.02 cases per 100 person-years. Traffic density and drinking water contaminant exposures were also associated with increasing IBS incidence, but these associations were not significant in both eras. Similarly, exposure to PM2.5, drinking water contaminants and airborne toxic releases from facilities were associated with FD incidence, though not in both eras. No significant associations were noted between pollutants and IBD or EoE incidence.CONCLUSION: Exposure to PM2.5 and airborne toxic releases from facilities are associated with higher IBS incidence among a cohort of commercially-insured Californians. Environmental pollutant exposure was not associated with the incidence of IBD and EoE in this cohort.

View details for DOI 10.1016/j.cgh.2022.09.025

View details for PubMedID 36202347