Jim Kling

November 06, 2012

LAS VEGAS, Nevada — Black people with Crohn's disease are more likely to have severe fistulizing perianal disease (FPD) than other groups, and white people are less likely to have FPD, according to a study presented here at the American College of Gastroenterology 2012 Annual Scientific Meeting and Postgraduate Course.

Up to one third of patients with Crohn's disease have perianal disease, which has been recognized as distinct from enteric fistulization. Some previous research has suggested that the phenotypic manifestations of Crohn's disease vary by race, but there is a dearth of research on perianal disease in adults with prespecified criteria for severity.

"In our day-to-day experience, [black patients] treated for inflammatory bowel disease tend to have really bad disease. They seem to present with [FPD] a lot," said Latifat Alli, MD, a resident at Mount Sinai Medical Center in New York City, who presented the research.

Dr. Alli and colleagues conducted a cross-sectional review of the electronic or paper charts of all adults with Crohn's disease who were treated with infliximab (Remicade) from May 1 to December 31, 2011.

The researchers reviewed gastroenterologists' notes and pathology reports in each chart to confirm the diagnosis and features of Crohn's disease, noting variables such as age, sex, self-reported race, and the presence or absence of a notation of FPD. They used Pearson's chi-squared analysis to compare FPD rates among black, white, and people of other racial groups.

Of the 333 evaluable patients, 73.6% were white, 11.4% were black, 13.2% were Hispanic, and 1.8% were Asian. Of the 88 of those who had FPD, 48 (54.5%) were white, 18 (20.5%) were black, 20 (22.7%) were Hispanic, and 2 (2.3%) were Asian.

The relative risk (RR) for FPD in black people was 1.87 (95% confidence interval [CI], 1.18 to 2.65; = .004). White people had a lower incidence of FPD than nonwhites (RR, 0.49; 95% CI, 0.35 to 0.70; P < .0001).

Genetics, Not Access, the Likely Explanation

"Is this a problem with access to care? Is this genetics? The good thing about our data is we're looking at our center, which means they all have the same type of insurance. We don't think [a difference in healthcare accessibility] is the reason. We think it's a genetic issue. That's going to be the next [subject of study] for us," said Dr. Alli.

"When you're...with a patient who is nonwhite, you have to think about a more careful perianal exam and...[be] more aggressive right upfront — asking questions about perianal discomfort and pain and other [symptoms] that you wouldn't necessarily think about," Sunanda Kane, MD, professor of medicine in the Department of Gastroenterology and Hepatology at the Mayo Clinic in Rochester, Minnesota, who was not involved in the study, told Medscape Medical News.

Dr. Alli and Dr. Kane have disclosed no relevant financial relationships.

American College of Gastroenterology (ACG) 2012 Annual Scientific Meeting and Postgraduate Course: Abstract P391. Presented October 21, 2012.