Ethnic differences in inflammatory bowel disease: Results from the United Kingdom inception epidemiology study

Abstract

BACKGROUNDThe current epidemiology of inflammatory bowel disease (IBD) in the multi-ethnic United Kingdom is unknown. The last incidence study in the United Kingdom was carried out over 20 years ago.AIMTo describe the incidence and phenotype of IBD and distribution within ethnic groups.METHODSAdult patients (> 16 years) with newly diagnosed IBD (fulfilling Copenhagen diagnostic criteria) were prospectively recruited over one year in 5 urban catchment areas with high South Asian population. Patient demographics, ethnic codes, disease phenotype (Montreal classification), disease activity and treatment within 3 months of diagnosis were recorded onto the Epicom database.RESULTSAcross a population of 2271406 adults, 339 adult patients were diagnosed with IBD over one year: 218 with ulcerative colitis (UC, 64.3%), 115 with Crohn's disease (CD, 33.9%) and 6 with IBD unclassified (1.8%). The crude incidence of IBD, UC and CD was 17.0/100000, 11.3/100000 and 5.3/100000 respectively. The age adjusted incidence of IBD and UC were significantly higher in the Indian group (25.2/100000 and 20.5/100000) compared to White European (14.9/100000, P = 0.009 and 8.2/100000, P < 0.001) and Pakistani groups (14.9/100000, P = 0.001 and 11.2/100000, P = 0.007). The Indian group were significantly more likely to have extensive disease than White Europeans (52.7% vs 41.7%, P = 0.031). There was no significant difference in time to diagnosis, disease activity and treatment.CONCLUSIONThis is the only prospective study to report the incidence of IBD in an ethnically diverse United Kingdom population. The Indian ethnic group showed the highest age-adjusted incidence of UC (20.5/100000). Further studies on dietary, microbial and metabolic factors that might explain these findings in UC are underway.

Incidence and Prevalence of Inflammatory Bowel Disease across Asia

“…In a recent epidemiologic study in 2016, the incidence of UC in an Indian group was higher (20.5 cases/10 5 /year) than that in a Pakistani group (11.2 cases/10 5 /year) and white European group (7.5 cases/10 5 /year) in the multi-ethic United Kingdom, although the study population was predominantly born in the United Kingdom. 14 Interestingly, the prevalence of CD in the same South Asian community in Leicester city was lower than that in Europeans (33.2 cases/10 5 /year vs. 75.8 cases/10 5 /year, respectively). 12 Indeed, research supports a difference between UC and CD epidemiology in immigrants: early life dysbiosis events, such as caesarean section, increased hygiene, and repeated antibiotics, are related to the risk of CD, whereas late dysbiosis events are related to the risk of UC.…”

Management of inflammatory bowel disease associated colonic dysplasia: factors predictive of patient choice and satisfaction

“…Twenty-one per cent of this study's participants were from a BAME background and therefore proportionally representative of the UK IBD population in ethnically diverse regions [26]. Compared to their white counterparts, the BAME cohort was less likely to state English as their main language but this did not appear to be a significant barrier to their decision-making as there were no differences in their CRC risk knowledge and they did not report feeling any less TA B L E 3 Thematic analysis of answers given by respondents for reasons why they did not feel well informed…”

Experiences of Ethnic Minority Patients Who Are Living with a Primary Bowel Condition or Bowel-Related Symptoms of Other Chronic Diseases: A Systematic Review

“…Misra et al (23) found that biological therapy for CD was prescribed signi cantly less often for South Asians compared to British White patients. Heterogeneity in disease phenotype in ethnic minority groups can be in uenced by differential cultural and environmental exposures (e.g., environmental pollutants, smoking and microbial exposure), forming an generational impact (13,23). In the UK, Misra et al (23) found that most second-generation Indians (aged 15 to 40) had higher age-adjusted incidence of UC compared to White Europeans and Pakistanis, indicating that subcultural differences amongst South Asians themselves needs further consideration, and that heightened genetic susceptibility and environmental triggers may promote the risk of developing UC with a non-colonic phenotype for Indian minority patients.…”

“…Ethnic minority patients may also receive poor healthcare. Misra et al (23) found that biological therapy for CD was prescribed signi cantly less often for South Asians compared to British White patients. Heterogeneity in disease phenotype in ethnic minority groups can be in uenced by differential cultural and environmental exposures (e.g., environmental pollutants, smoking and microbial exposure), forming an generational impact (13,23).…”

“…Heterogeneity in disease phenotype in ethnic minority groups can be in uenced by differential cultural and environmental exposures (e.g., environmental pollutants, smoking and microbial exposure), forming an generational impact (13,23). In the UK, Misra et al (23) found that most second-generation Indians (aged 15 to 40) had higher age-adjusted incidence of UC compared to White Europeans and Pakistanis, indicating that subcultural differences amongst South Asians themselves needs further consideration, and that heightened genetic susceptibility and environmental triggers may promote the risk of developing UC with a non-colonic phenotype for Indian minority patients. Carr and Mayberry (13) found greater disease severity in second generation South Asians with UC (living in the UK for a minimum of 25 years) compared to rst generation migrants and the indigenous population, although the reason for such differences remain unclear.…”