Objectives: To define the characteristics of a population of veterans with rheumatoid arthritis (RA) who have stopped or switched their first biologic agent, and to assess if measures of disease activity are predictors in the decision to alter the regimen.
Methods: A retrospective analysis of the VA electronic medical record system identified RA patient demographic and disease activity parameters from 1999 to 2007. Demographic data included age, race/ethnicity, sex, and tobacco use. Disease-specific data included date of RA onset, past DMARD therapies, prednisone use, as well as the disease activity score (DAS-28) and the health assessment questionnaire (HAQ) at each clinic visit. The use of six biologicals (infliximab, etanercept, adalimumab, abatacept, rituximab, anakinra) was identified in order to compare those who continued with the medication to those discontinuing or switching to another biological. Descriptive and parametric statistics were applied to define differences between the two groups.
Results: Of 454 RA patients identified, 212 have been on a biologic agent at one point in time, and 100 patients (47%) had either stopped or switched their first biologic agent. Among these 100 patients, the most common reasons for stopping or switching a biologic agent were adverse events (in 48%) and inefficacy (43%) Adverse events included malignancies (23% of 48 patients), rash (23%), infections (18.8%), and cardiac complications (18.8%). When comparing the 100 patients versus the 112 that did not stop or switch their first agent, the DAS-28 correlated significantly with a change of regimen with an OR 2.1 (p<0.001). The HAQ score had an OR of 2.0 (p<0.04).
Conclusion: RA patients who continue taking their initial biologic medication have similar age, RA disease duration, ethnicity, and smoking status to those requiring switching or discontinuation. The DAS28 and HAQ scores significantly correlated with stopping or switching of a first biologic agent. Adverse event rates were high and their distributions differed in this population compared to previous studies of younger Caucasian females.