TIMING OF DECISIONS TO ADJUST DISEASE MODIFYING ANTI-RHEUMATIC DRUG THERAPY FOR RHEUMATOID ARTHRITIS PATIENTS WITH ACTIVE DISEASE

Purpose:

Current guidelines recommend that rheumatoid arthritis (RA) patients with active disease have therapy with disease modifying anti-rheumatic drugs (DMARDs) adjusted until reaching low disease activity or remission. We examined factors associated with timing of decisions to adjust DMARD therapy for RA patients with active disease and how the timing of decisions impacts resolution of active disease.

Methods:

Data came from the University of Pittsburgh Rheumatoid Arthritis Comparative Effectiveness Research (RACER) registry, which captures subjects' disease activity status (DAS28-CRP) and medications at clinic visits.

We conducted survival analyses on time to DMARD therapy adjustment and time to resolution of active disease for RACER subjects with active disease. A Cox proportional hazards model was used to assess the impact of covariates on the survival times. For both analyses, followup begins when the subject is first known to have active disease (DAS28-CRP>3.2) and ends with the event of interest (DMARD therapy adjustment or resolution of active disease). For the analysis of time to therapy adjustment, we excluded patients who augmented therapy at t=0 and those who exited active disease before adjusting therapy, and the model included covariates for age, gender, African-American race, comorbidities, duration of RA, and current use of a biologic therapy.  For the analysis of time to resolution of active disease, the model included the same covariates plus one additional variable for time to therapy adjustment.

Results:

The analysis for time to therapy adjustment included 336 subjects (188 therapy augmentations observed). Age over 75, male gender, and longer duration of RA were significantly associated with longer times to therapy adjustment.

The analysis for time to resolution of active disease included 530 subjects (383 achieved low disease activity/remission). African-American race and duration of RA >1 year were associated with longer times to resolution of active disease. (See Table 1)

Conclusions:

We found important patient characteristics that are associated with less responsive changes in treatment adjustment and poorer disease outcomes for RA patients with active disease. Future studies should examine in more depth how these characteristics affect treatment choices as well as long term health outcomes.