June 12, 2013
Poor RA Medication Adherence Rates Found in Diverse, Low-Income Group

Houston—Medication adherence rates are too low for many rheumatoid arthritis patients, including more than a third of those taking nonbiologic disease modifying anti-rheumatic drugs (DMARDs), according to a new study conducted in an ethnically diverse and predominantly low-income population.

The report, from researchers at the University of Texas in Houston, was published recently in the journal Arthritis & Rheumatism.

For the study, researchers at UT’s MD Anderson Cancer Center electronically monitored intake of oral RA medication in 107 patients over a 2-year period. Of those who participated, 87% were female with a mean disease activity of 8 years. Patients taking part in the study were ethnically diverse—65% Hispanic, 19% African-American, and 16% Caucasian—and had low educational status, with 45% not completing high school. About two-thirds (67%) had annual incomes less than $20,000.

DMARD adherence was measured using the following:

• Doses taken as prescribed: Percentage of days or weeks for methotrexate or prednisone in which the patient took the correct dose as prescribed
• Underdosing: Percentage of days or weeks in which the patient took fewer doses than prescribed
• Overdosing: Percentage of days or weeks that the patient took more doses than prescribed

RA patients who took their medications as prescribed were considered adherent—64% for DMARD therapy and 70% for prednisone.

Only 21% of participants adhered to their DMARD therapy, however, and 41% correctly took prednisone at least 80% of the time. Researchers found that patients with better mental health and who were not widowed or separated tended to be more compliant.

Taking medications as prescribed significantly lowered disease activity scores (DAS28 at 3.3) throughout the study period, as compared to those who were less adherent (DAS28 at 4.1). Increases in radiological damage scores were also higher in RA patients who were nonadherent.

“Our study is the first to measure drug adherence in RA patients over the long-term, and emphasizes the importance of following the prescribed regimen to manage their disease," the authors note.

They recommend that health care providers “work with patients to understand their reasons for non-adherence and discuss the importance of taking medications as prescribed to control RA symptoms and prevent disease progression.”

U.S. Pharmacist Social Connect