P090 SOUTH ASIANS IN THE UNITED STATES HAVE MORE AGGRESSIVE PENETRATING AND PERIANAL CROHN’S DISEASSE

• Published in: Inflammatory bowel diseases Vol. 25; no. Supplement_1; pp. S42 - S43
• Main Authors: Jangi, Sushrut, Ruan, Alex, Desilva, Punyanganie
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 07.02.2019
• ISSN: 1078-0998; 1536-4844
• DOI: 10.1093/ibd/izy393.097

Abstract Background South Asians (SA) have recently been identified as having a rapidly rising incidence and prevalence of inflammatory bowel disease (IBD) throughout the world. However, longitudinal phenotypic studies of SA living in the United States remain scarce. Methods We retrospectively studied 171 SA patients with IBD treated at two US tertiary centers. Patients were followed between 2000 and 2016 from the time of initial presentation until the last documented visit. All SA IBD patients were randomly matched in 1:2 ratio with sex and IBD subtype -matched (UC vs CD) Caucasian controls (n=342). Diagnosis was confirmed based on histological and radiological data. Demographic and phenotypic characteristics including disease extent, disease distribution, medication use patterns, and procedural utilization were evaluated and compared between the two groups. Odds ratios, logistic regression, and time-to-event analysis was performed using R studio. Results 81 SA and 162 Caucasians were identified as having CD while 90 SA and 180 Caucasians were identified as having UC. There were less smokers in the SA with UC group (8.9% vs 23.9%, p<.005). SA with CD were more likely to be diagnosed at an older age (27.4 years +/- 11.2 years) compared to Caucasians with CD (23.6 +/- 11.1 years, p<.003). SA with CD were more likely to present with rectal or perianal pain (15.9% vs 2.9%, p<.001). Penetrating disease (24.1% vs 8.6%, p<.002) and perianal disease (20.3% vs 2.5%, p <0.005) were more common among SA with CD. After adjusting for covariates, SA with CD were less likely to be placed on thiopurines (OR = 0.72, p<.033) or receive more than one biologic during the follow up period (OR =0.81, p<.045). There was no significant difference in surgical utilization between SA and Caucasians. SA with UC were less likely to have proctitis (10% vs 22.2%, p<.022) and were more likely to have primary sclerosing cholangitis (7.8% vs 1.1%, p<.007). Conclusion As far as we are aware, this is one of the first longitudinal studies evaluating long term outcomes in South Asian adults with inflammatory bowel disease living in the United States. We find unique demographic and phenotypic characteristics among South Asians, including more aggressive penetrating disease in those with CD and less distal disease and higher rates of PSC among those with UC. Smoking appears less relevant as a risk factor among South Asians with UC. Distinct environmental exposures in the United States and a potentially unique genetic profile of South Asians may confer this variable phenotypic expression, influencing diagnosis and management of this increasingly at-risk population.