The relationship between sinusitis and inflammatory bowel disease (IBD) has not yet been established. Though the two are characterized by dysfunction of the epithelial barrier, there lacks evidence on the relative contributions of infection or inflammation to this co-morbidity in IBD patients. Previous analysis from our group (ACG 2019) identified an increased prevalence of sinusitis among patients with IBD, but that work did not include a stratified analysis of IBD patients with sinusitis based on the order in which these conditions were diagnosed.