PTU-046 The prevalence of extraintestinal manifestations associated with inflammatory bowel disease differs between ethnic groups in the UK

Abstract

Introduction The incidence and prevalence of inflammatory bowel disease (IBD) is increasing throughout Asia. Since the 1950s, there has been substantial migration from South Asia (India, Pakistan, Bangladesh and Sri Lanka) to the UK. Currently 2.33 million South Asians live in the UK and 0.86 million live in London. There have been no previous studies reporting the prevalence of extraintestinal manifestations (EIMs) associated with IBD in this population. Methods The aim of the study was to establish whether there are differences in the prevalence of EIMs in a cohort of UK South Asian IBD patients compared with a British Caucasian IBD cohort. The medical notes of IBD patients attending five hospitals in North West London were monitored for a 2-year period between 2007 and 2009 to identify South Asian patients under active follow-up. IBD patients with any EIMs were recorded. EIMs were defined as joint complications (Type 1 or 2 peripheral arthropathy, ankylosing spondylitis and sacroiliitis), skin complications (erythema nodosum and pyoderma gangrenosum), anterior uvetitis and primary sclerosing cholangitis. The data were compared with an established database of British Caucasian IBD patients (609 ulcerative colitis (UC): 560 Crohn9s disease (CD)) using the χ 2 test. Results A total of 371 South Asian IBD patients were studied (271 UC: 100 CD). Forty-one patients (11%) had at least one EIM. Twenty-five (9.2%) of the South Asian UC population had an EIM associated with IBD. This was significantly lower than the Caucasian population (112/609; 18.4%) ( P =0.0005). The most common EIM in South Asians UC patients was type 1 (large joint) peripheral arthritis (7/271; 2.6%). EIMs were also more common in the Caucasian CD cohort (148/560; 26.4%) than the South Asian CD cohort (16/100; 16%) ( P =0.03). Erythema nodosum was the most common EIM in South Asian CD patients (5/100; 5%). Conclusion This is the first study of EIMs in a UK South Asian IBD cohort and shows that they are significantly less common compared to a British Caucasian IBD population. As several studies have reported an association between EIMs and HLA gene polymorphisms in Caucasians, differences in the prevalence of EIMs may reflect variation in HLA polymorphisms between the groups. Further genetic studies are required to determine the answer.