Introduction Previous epidemiological studies suggest a higher rate of pan-colonic disease in South Asians (SA) compared with Caucasians. There is limited data on disease severity across ethnic groups. Refractory disease and development of dysplasia indicate aggressive disease and are both indications for colectomy. The aim of the study was to compare the risk of colectomy for ulcerative colitis (UC) in SA migrants to Caucasians.

Method Patients with UC were identified from a national administrative dataset (Hospital Episode Statistics – HES) between 1997–2012 according to ICD-10 diagnosis code K51 for UC. From the cases coded for ethnicity, colectomy cases were identified according to the Office of Population Censuses and Surveys (OPCS) codes. The colectomy rate for each ethnic group was calculated as the proportion of patients who underwent colectomy from the total UC cases for that group. The median age at time of colectomy was calculated for each ethnic group. Chi-squared testing was used to determine significant differences in colectomy rate and Kruskal-Wallis test to ascertain differences in age at colectomy between ethnic groups.

Results Of 212,430 UC cases, 74,988 (35.3%) were coded for ethnicity. Of these cases most were White Europeans (Caucasians) 69,208/74,988 (92.3%). The SA group consisted of: 1,954/74,988 (2.6%) Indian, 832/74,988 (1.1%) Pakistani and 129/74,988 (0.2%) Bangladeshi (Table 1). Indians had a significantly higher colectomy rate than White Europeans (10.8% vs 7.4%, p < 0.001). In contrast Pakistanis had a similar (7.0%) and Bangladeshis a significantly lower (4.7%) colectomy rate than the White European group. (7.4%, p < 0.001). SAs undergoing colectomy were significantly younger than White Europeans for each ethnic group (median age; Bangladeshis - 29 years, Pakistanis - 37 years and Indians – 41 years, compared with White Europeans – 49 years, p < 0.001).

Conclusion The colectomy rate is higher in Indians compared to White Europeans. Across SA ethnic groups there are differences in colectomy rate. All SA groups required a colectomy for UC at a younger age than White Europeans. These findings suggest a more aggressive phenotype in SAs and should be validated with a prospectively recruited ethnic cohort. This will also allow examination of contributing factors.

Disclosure of interest None Declared.