On the Question of Ethnicity and Its Impact on IBD-Related Outcomes

The global incidence of inflammatory bowel disease (IBD) has risen steadily over the last half century [1]. Previously considered a disease which predominantly afflicted Caucasians in industrialized countries, IBD is being increasingly reported in developing countries as they become ‘‘Westernized,’’ supporting the importance of environmental factors in disease pathogenesis [1, 2]. Moreover, rates of IBD among immigrant and minority populations in Canada and several western European countries are rising [2, 3]. Though population-based studies in the United States are lacking, one recent study utilizing the National Inpatient Sample (a large nationally-representative database of hospital admissions), demonstrated a temporal increase in non-white minority patients hospitalized for IBD over the last decades [4]. Within the United States, Hispanics are amongst the largest and fastest-growing minority groups, currently accounting for 16 % of the US population. Data regarding ethnic variations of disease epidemiology and phenotype amongst Hispanic IBD patients have been limited, with available literature inconsistent. For instance, there is conflicting data on whether Hispanics have higher or lower rates of Crohn’s disease [5–7], perianal complications [6, 8], and extraintestinal manifestations [5–7], when compared to Caucasians. This variability of findings is probably due to the genetic heterogeneity of Hispanics in the United States, which can include European (Spanish and Portuguese), Caribbean, and Native-American ancestry. Caribbean Hispanics are often categorized as Black (African descent) or White (European) races. With regard to treatment and outcome disparities amongst Hispanics, the current literature highlights the difficulty of separating ethnic-based differences in disease course with issues of access to care. Several retrospective studies of underserved cohorts in safety-net hospitals have suggested a smaller proportion of Hispanic IBD patients, compared to Caucasians, are prescribed immunomodulator and biologic therapy for their disease [5, 7]. Moreover, Hispanics appear to be less likely to undergo surgery for UC and Crohn’s, based on two studies utilizing the National Inpatient Sample [8, 9]. Nevertheless, patients with Medicaid were also less likely to undergo surgery than patients with private insurance, suggesting a potential contribution from socioeconomic factors. Given these apparent treatment disparities, one might suspect that Hispanic IBD patients would have poorer outcomes. In particular, surgical outcomes would be expected to underscore ethnic disparities amongst the sickest IBD patients, given surgery is reserved for medically-refractory disease or disease complications (strictures, fistulas, neoplasia). In this month’s Digestive Diseases and Sciences, Dr. Yarur and colleagues report on their findings of surgical outcomes amongst Hispanics compared to non-Hispanics [10]. To date, this is the first study evaluating ethnic differences in perioperative complication rates of IBD-related surgery. Importantly, the authors sought to control for access to care issues by comparing Hispanic and non-Hispanic patients within a single safety-net health care system (Miami-Dade County) and including only patients who received regular gastroenterological care for at least 6 months prior to their surgery. Socioeconomic differences were thought less likely, C. Hwang Division of Gastrointestinal and Liver Diseases, University of Southern California, Los Angeles, CA, USA