727 Clinical Epidemiology of Inflammatory Bowel Disease in Los Angeles County: A Study of a Predominantly Latino Population

Abstract

INTRODUCTION: The body of research pertaining to the epidemiology, features, and treatment of inflammatory bowel disease (IBD) continues to grow; however, relatively little remains known about IBD in minority populations. Hispanics and Blacks have been understudied in most population studies, often comprising <2% of the sample size. This disproportion limits the ability to formulate reliable conclusions regarding ethnoracial influences on incidence, phenotype, severity of disease, and outcomes in these minority groups. To help address this void, we initiated a population-based study of the clinical epidemiology of IBD in Los Angeles County Department of Health Services (LADHS), the second largest municipal healthcare system in the United States. The ethnoracial makeup of the county is comprised predominantly of Latino patients, which provides a unique opportunity to evaluate IBD in a population that has not been well-studied to date. METHODS: We conducted a retrospective cohort study of all biopsy-proven cases of IBD diagnosed between November 2015 and June 2018 at Olive View-UCLA Medical Center, one of three hospitals comprising LADHS. Patient and disease-related data such as age, gender, ethnicity, presenting symptoms and laboratory values, and complications, were collected using a standardized data collection tool and tabulated. RESULTS: One hundred and twenty-six cases of IBD were found, of which 42 were new diagnoses, suggesting an incidence and prevalence of 160 and 481 per 100,000 person-years, respectively. Among these 126 patients, 79% were Latino, with the average age of diagnosis at 36.4 years. 54% of patients were female. The most common diagnosis was ulcerative colitis (43%), with Crohn's and indeterminate colitis making up 29% and 28% of patients, respectively. The most common presenting symptoms were bloody diarrhea and abdominal pain, both of which occurred more frequently in patients diagnosed with Crohn's disease. CONCLUSION: Both the prevalence and incidence in this predominantly Hispanic cohort are significantly higher than reported rates for IBD by the Center of Disease Control (CDC), Furthermore, this cohort appears to have unique clinical characteristics, with UC more common in females, Crohn's disease more common in males, and a large proportion of patients having indeterminate colitis. Further evaluation is needed to better understand the characteristics, etiopathogenesis, and outcomes of IBD, as well as reduce healthcare disparities in this historically understudied population.