P745 Incidence of indeterminate colitis in the EPIMAD registry decreases over the period 1988–2014
P. Mayer*1, H. Sarter2,3, M. Fumery2,4, G. Savoye5, A. Leroyer3, L. Dauchet3, C. Gower-Rousseau2,3, B. Pariente1
1Lille University Hospital, Gastroenterology Unit, Hôpital Huriez, Lille, France, 2Lille University, CHRU de Lille, Lille Inflammation Research International Centre LIRIC - UMR 995 Inserm, Lille, France, 3Lille University and Hospital, Public Health, Epidemiology and Economic Health, Register Epimad, Lille, France, 4CHU Amiens Sud, l, Amiens University Hospital, Gastroenterology Unit, Epimad Registry, Amiens, France, 5Hôpital Charles Nicolle, Rouen University Hospital, Gastroenterology Unit, Epimad Registry, Rouen, France
Inflammatory bowel disease unclassified (IBDU) represents 5–15% of new diagnosis of inflammatory bowel disease. However, IBDU is not well defined and high rate of reclassification in Crohn’s disease (CD) or Ulcerative colitis (UC) is observed during follow-up. The objective of the present study was to evaluate the evolution of the incidence of IBDU over the period 1988–2014 in a population-based study and its reclassification rate during the follow-up.
All adults (> 17 years old) patients diagnosed with IBDU according to a validated and published algorithm1 in the French population-based registry EPIMAD from 1988 to 2014, were identified. Follow-up was divided in 3 periods of 9 years (1988–1996, 1997–2005, and 2006–2014). Reclassification was defined as a modification of diagnosis during the follow-up.
24 304 IBD cases (> 17 years) were diagnosed, including 8449 (66.2%) CD, 3839 (30.1%) UC and 476 (3.7%) IBDU. IBDU concerned predominantly males compared with CD and UC population [(51.7% in IBDU population (
In this population-based study, IBDU incidence decreased significantly between 1988 and 2014, probably because of better diagnosis performances allowing CD and UC identification. These results suggest that IBDU may not be a real and significant clinical entity but a misclassification of colonic inflammatory bowel disease.