To delineate compliance with drug therapy in rheumatoid arthritis patients, determine specific characteristics of compliant and noncompliant patients, and look for changes in compliance over time.
A prospective European cohort study (EURIDISS) recruited 556 patients in four countries over three years. Compliance with drug dosages and dosing times was evaluated yearly using a questionnaire.
Of the 556 patients, 429 (77.2%) were on drug therapy at all three evaluation time points. Use of steroids, nonsteroidal anti-inflammatory drugs, and second-line drugs varied significantly across countries. The compliance behavior was stable over time in 59.5% of them (35.7% of patients were consistently compliant and 23.8% consistently noncompliant); it was independent of disease duration and from the clinical features of the disease. Older patients and women were more likely to be compliant (odds ratios, 2.5 and 2, respectively).
Compliance with drug therapy can be measured using two simple questions. Compliance is more closely dependent on individual behavior than on responses to specific features of rheumatoid arthritis.