WASHINGTON – Black patients with inflammatory bowel disease were significantly more likely to have at least one extraintestinal manifestation of the disease than were white patients, particularly uveitis, in a study of more than 500 people with Crohn’s disease or ulcerative colitis, Dr. Jemilat Badamas reported at the annual Digestive Disease Week.
Black patients were about twice as likely to have uveitis than were white patients in the study, after researchers controlled for other risk factors for extraintestinal manifestations of IBD, said Dr. Badamas, a gastroenterology fellow at Johns Hopkins University, Baltimore. Based on these results, and the increased rate of uveitis among black IBD patients seen in other studies, “practitioners should consider proactive referral of African-Americans [with IBD] to be screened for uveitis,” she said.
The study compared the incidence of various extraintestinal manifestations of IBD among 196 black patients and 342 white patients with a confirmed diagnosis of Crohn’s disease (CD) or ulcerative colitis (UC), which included uveitis, small and large joint disease, sacroiliitis, ankylosing spondylitis, episcleritis, pyoderma gangrenosum (PG), erythema nodosum (EN), and progressive sclerosing cholangitis, confirmed in the medical records. All the patients had been treated at outpatient gastroenterology clinics and infliximab infusion clinics at Johns Hopkins Hospital, including patients who were hospitalized and were subsequently followed up at the GI clinics. Cases with no information on extraintestinal manifestations were excluded.
Enrollment of all patients at one medical center overcame one of the limitations of previous studies evaluating racial differences in extraintestinal manifestations of IBD, where most of the black and white patients were treated in different centers, so researchers could not account for differences in practices at different institutions or access to subspecialty care, she pointed out.
In the Johns Hopkins study, patients in both groups were diagnosed with IBD at a mean age of 28-29 years. Among the black patients, 62% were female and they were enrolled in the study at a mean age of 38 years. Among the white patients, half were female and they were enrolled at a mean age of 41 years. The data on these patients are being collected as part of the Multicenter African American Inflammatory Bowel Disease Study (MAAIS).
More black patients (41%) had at least one extraintestinal manifestation of IBD compared with white patients (33%). The most common was large joint disease, affecting 25.5% of black patients and 19% of white patients, Dr. Badamas said. Uveitis was more common in black patients (6.9% vs. 2.7%), a difference that was statistically significant (P = 0.021). Pyoderma gangrenosum was more common in black patients (4.8% vs. 1.8%), a difference of borderline significance (P = 0.051).
After the researchers controlled for gender, disease location, and extent of disease, which are factors known to be associated with extraintestinal manifestations of IBD, there were no significant differences between the two groups for most of the manifestations, she said. But black patients were about two times more likely to have uveitis, compared with white patients (odds ratio, 2.3), and were 1.5 times more likely to have at least one extraintestinal manifestation (OR, 1.5), she added.
The study did not include a temporal analysis to determine if any of these manifestations occurred before the diagnosis of IBD was made, but Dr. Badamas said that most were diagnosed after the diagnosis of IBD.
Dr. Badamas had no relevant disclosures.