P770 Epidemiology of inflammatory bowel diseases in French Polynesia
V. Grymonpré1, A. Loria2, E. Beaugendre2, B. Condat2, B. Tassy1, N. Bouta1, M. Bismuth1, F. Panaro3, J-C. Valats1, P. Blanc1, G. Pineton de Chambrun*1
1Montpellier University Hospital, Gastroenterology, Montpellier, France, 2French Polynesia General Hospital, Gastroenterology, Papeete, French Polynesia, 3Montpellier University Hospital, Digestive Surgery, Montpellier, France
The prevalence of inflammatory bowel diseases (IBD) in Southeast Asia has been rapidly growing over the last 50 years. French Polynesia is an overseas territory located in South pacific which comprised in 2018, 275 918 inhabitants. No epidemiologic data on IBD are available in this population who has a single genetic and environmental background. The aim of this study was to describe the incidence, prevalence, characteristics and evolution of IBD patients in French Polynesia.
We performed a retrospective, multi-centre, cohort study including all patients with Crohn's disease (CD) or ulcerative colitis (UC) diagnosed and/or followed in general hospital or clinics in French Polynesia between January 2011 and April 2018. The diagnosis of IBD was based on clinical, biological, endoscopic and histological criteria. Three groups of patients were defined: Polynesians; Immigrants who developed IBD in Polynesia; and immigrants who developed IBD before their arrival in Polynesia.
A total of 49 patients (25M, 24F) with IBD (27 CD, 30 UC) were identified in French Polynesia. The IBD overall prevalence in French Polynesia was 17 cases per 100 000 inhabitants (11/100 000 for UC and 6/100 000 for CD). Only five Polynesians were diagnosed with IBD (4 UC, 1 CD). Among immigrants, 12 (6 UC, 6 CD) IBD patients were diagnosed before their arrival in Polynesia and 21 (16 UC, 4 CD) developed their IBD in Polynesia. The prevalence of IBD in Polynesians was 1.2 cases/100 000 inhabitants (1.5/100 000 for UC and 0.4/100 000 for CD). The prevalence of IBD in immigrants who developed their IBD in Polynesia was 203 cases/100 000 inhabitants (154/100 000 for UC and 39/100 000 for CD). The mean overall incidence of IBD in Polynesians was 0.1 cases/100 000 inhabitants and 13 cases/100 000 inhabitants for immigrants. The median age at diagnosis of IBD was 43.4 (IQR: 34.1–51.2) years. The majority of IBD patients (72%) were Caucasian. No Polynesian with IBD required immunosuppressive therapy, biologic or surgery. Among immigrants who developed IBD in Polynesia, 19% of cases received immunosuppressive drugs, 14% received biologics and only one underwent surgery. Among immigrants with IBD before their arrival in Polynesia, 45% received immunosuppressive drugs and 66% biologics.
The results of our study demonstrate a very low prevalence of IBD among Polynesians as it was observed in Southeast Asia 50 years ago. The prevalence of IBD among immigrants who developed their disease in Polynesia is similar to IBD prevalence currently observed in European countries. The IBD developed in Polynesia seemed to require less immunosuppressive drugs, biologics or surgery.