S760 Epidemiology of Glomerulonephritis as an Extraintestinal Manifestation of Inflammatory Bowel Disease: A Large Population-Based Study

Abstract

Introduction: Inflammatory bowel disease (IBD), including both Crohn’s disease (CD) and Ulcerative colitis (UC), are known to cause many extraintestinal manifestations. There is limited data describing the association between IBD and renal manifestations. This study provides epidemiologic data to further understand the association between IBD and glomerulonephritis (GN). Methods: The aim of this study was to investigate if IBD is associated with GN. Data was collected from a commercial database (Explorys Inc, Cleveland, OH), an aggregate of EHR data from 27 integrated healthcare systems in the US between 1/2017-1/2022. We identified patients with CD and UC based on Systemized Nomenclature of Medicine – Clinical Terms. We compared the prevalence of GN at least 30 days post-CD or post-UC diagnosis to a control cohort without CD or UC. We excluded patients with a diagnostic predisposition for development of GN (Table). Results: Of the 34,063,760 patients, we identified 149,630 cases of CD and 127,300 cases of UC. There were 310 and 260 cases of glomerulonephritis at least 30 days after diagnosis of CD and UC, respectively. Overall prevalence of glomerulonephritis for CD and UC was 207/100000 persons and 203/100000 persons, whereas for the cohort without CD and UC was 72/100000 persons and 72/100000 persons. Prevalence ratios (PR) of developing glomerulonephritis after at least 30 days of a CD and UC diagnosis were 2.88 (95% CI, 2.57-3.22, p< 0.001) and 2.83 (95% CI, 2.51-3.20, p< 0.001), respectively. Figure shows prevalence and PR in CD and UC sub-categorized by demographics. Membranous GN was the most prevalent (CD 90, UC 90), followed by proliferative (CD 50, UC 50), mesangiocapillary (CD 30, UC20), diffuse (CD 10, UC 0) and focal membranoproliferative (CD 10, UC 10). Conclusion: In this large population-based study, glomerulonephritis was significantly more prevalent in patients with both CD and UC compared to those without IBD. Further studies are needed to understand the pathophysiological mechanism underlying renal involvement.Figure 1.: Prevalence and prevalence ratios of glomerulonephritis after at least 30 days post-CD and post-UC diagnosis. Table 1. - Diagnoses excluded prior to analysis Excluded diagnoses Systemic lupus erythematosus Goodpasture's syndrome Hereditary nephritis Post-infectious GN Granulomatosis with polyangiitis Allergic grandulomatosis angiitis Alport syndrome Human immunodeficiency virus Hepatitic B virus Hepatitis C virus Nephrotic syndrome with membranoproliferative glomerulonephritis Primary pauci-immune necrotizing and crescentic glomerulonephritis Berger's immunoglobulin A or immunoglobulin G nephropathy