Biologic disease-modifying antirheumatic drugs revolutionized the treatment of rheumatoid arthritis, or RA, when the first ones were introduced more than a decade ago. The drugs are associated with better control of RA, less joint damage and higher rates of remission, but a new study finds that African-Americans are less likely to use them.

The study, published in Arthritis Care & Research, analyzed the records of 5,385 adult RA patients in California, all of whom had been prescribed either a biologic or a standard disease-modifying antirheumatic drug, or DMARD. The biologics in the study included: etanercept, or Enbrel; adalimumab, or Humira; anakinra, or Kineret; and infliximab, or Remicade. The traditional DMARDs included: methotrexate, or Rheumatrex; lefluonomide or Arava; hydroxychloroquine, or Plaquenil; and sulfasalazine, or Azulfidine.

The researchers set out to discover whether race/ethnicity played a role in determining what type of DMARD a patient was prescribed. The verdict, according to the data, is it does. The results show that just over 15 percent of all patients were prescribed a biologic – but only 9 percent of African Americans were, compared to 16 percent of Caucasians and 20 percent of Hispanics. Looked at another way, the numbers show African-Americans were 53 percent less likely to receive a biologic DMARD than Caucasians, and Hispanic patients were 36 percent more likely to get one than Caucasians.

The study, considered “retrospective” because it looked at existing records, used data from California’s Medicaid system, known as Medi-Cal, between 1998 to 2005. 

“I was surprised by the magnitude of these differences,” says study author Aniket Kawatkar, PhD, a research scientist in the Department of Research and Evaluation at Kaiser Permanente Southern California. “The fact that African-Americans are at 53 percent lower odds suggests there may be an urgent need for interventions targeted to reduce barriers in the uptake of biologic DMARDs in this race group.”