LAS VEGAS – Immunosuppressant thiopurine drugs are a common and often successful treatment for patients with inflammatory bowel disease (IBD), but they can cause serious side effects via myelosuppression. Now, a new study suggests that a racial gap may prevent minority patients from being promptly diagnosed with myelosuppressive side effects.
“We found that minority IBD patients – black, Hispanic, Asian/Pacific Islander – had significantly higher hospitalization rates that were due to myelosuppressive events compared to white IBD patients,” lead author Ryan Suk, MS, said in an interview. “Among those IBD patients who were hospitalized due to myelosuppression, black and Hispanic IBD patients had a significantly higher chance of getting admitted as urgent compared to white IBD patients.”
Ms. Suk, a health economics graduate student at the University of Texas, Houston, spoke in an interview prior to the presentation of her study’s findings at the Crohn’s & Colitis Congress - a partnership of the Crohn’s & Colitis Foundation and the American Gastroenterological Association.
According to Ms. Suk, multiple studies have previously revealed racial and ethnic disparities in health care access and use by minority patients with IBD.
She pointed to a 2010 study that found black patients with IBD were much less likely than whites were to see a gastroenterologist or IBD specialist at least once a year. She also cited a 2009 study that found black patients with IBD were significantly less adherent than were white patients; researchers linked older age and higher trust in physicians to higher levels of adherence (Am J Gastroenterol. 2010 Oct;105[10]:2202-8; Inflamm Bowel Dis. 2009 Aug;15[8]:1233-9).
In light of these findings, she said, “we questioned what the possible results of thiopurine use could be in minority patients without proper and consistent routine IBD care.”
While thiopurine is considered a standard form of care for IBD patients, Ms. Suk said an estimated one-third of patients must stop the treatment because of side effects such as anemia, leukopenia/neutropenia, and thrombocytopenia.
For the new study, Ms. Suk and her colleagues tracked patients who were hospitalized with a primary diagnosis of IBD or IBD-related complications from 2003-2014 via the Nationwide Inpatient Sample. There were 249,253 white patients, 192,864 black patients, 28,956 Hispanic patients, 17,073 Asian/Pacific Islander patients, and 2,849 patients in the “other” category.
The researchers found higher odds of hospitalization for myelosuppression in minorities compared with non-Hispanic whites: Non-Hispanic blacks (adjusted odds ratio = 1.3; 95% confidence interval [1.2-1.4], vs. whites), Hispanics (aOR = 1.6; 95% CI [1.4-1.7], vs. whites), and Asian/Pacific Islanders (aOR = 2.3; 95% CI [1.9-2.8], vs. whites).
The researchers found that among patients diagnosed with myelosuppression, two groups – non-Hispanic blacks and Hispanics – had higher odds of being admitted urgently, compared with non-Hispanic whites (aOR = 1.7; 95% CI [1.2-2.3] and aOR = 1.6; 95% CI [1.1-2.2] vs. whites, respectively).
“Unlike Asian/Pacific Islander patients, black and Hispanic patients had a higher likelihood of getting hospitalized from myelosuppression and also higher likelihood to get admitted urgently compared to the white cohort,” Ms. Suk said. “It is possible that they have less access to thiopurine management and monitoring, leading to developing more severe adverse events and therefore having urgent myelosuppressive hospitalizations.”
As for Asian/Pacific Islander patients, she noted that they had the highest likelihood of myelosuppression hospitalization but did not have the highest chance of getting admitted as urgent. “We think that Asians have a higher risk of myelosuppression due to genetic factors, not from less access to care, and thus they had more elective hospitalizations,” she said.
The researchers also linked Medicaid, self-pay, and no-charge patients to higher levels of myelosuppression hospitalizations. “This shows that patients who have less access to care [need more] urgent admission from myelosuppressive events,” Ms. Suk said.
No funding was reported, and the study authors had no relevant disclosures.
SOURCE: Suk R et al. Crohn’s & Colitis Congress, Abstract P059.