Increased healthcare resource utilization in higher disease activity levels in initiators of TNF inhibitors among US rheumatoid arthritis patients.

OBJECTIVE: Determine healthcare resource utilization (HCRU) in biologic-naïve initiators of TNF inhibitors (TNFis) associated with their disease activity from a national cohort of rheumatoid arthritis (RA) patients.

METHODS: RA patients were identified at their first TNFi initiation (index date) in the Corrona registry. Patients with age of RA onset <18, comorbid psoriasis/psoriatic arthritis, fibromyalgia, or osteoarthritis were excluded. Patients were categorized into disease activity (DA) strata by the lowest level of DA (and sustaining low levels for at least two visits) using the Clinical Disease Activity Index (CDAI) across all visits in Corrona while on a TNFi during 1 year after initiation. Rates of all-cause and RA-related hospitalizations, rheumatologist visits, and joint surgeries while on TNFi therapy were reported and compared across DA levels along with the incidence rate ratio (IRR) adjusted for age, gender, and RA duration using Poisson mixed models.

RESULTS: Of 1931 RA patients: 15% achieved sustained remission, 22% remission, 14% sustained low DA, 23% low DA and 27% moderate/high DA (M/HDA). Those in M/HDA had statistically higher rates of hospitalizations (37.3 per 100 patient years (py), 95% CI: 31.6-43.7 and joint surgeries (20.8 per 100 py, 95% CI: 16.6-25.8) compared to the sustained remission cohort, resulting in respective IRRs of 2.3 (p < 0.001) and 1.7 (p = 0.046).

CONCLUSION: Many biologic naïve RA patients initiating TNFi failed to achieve sustained remission during a 1 year period while remaining on TNFi therapy. Patients in higher DA levels had higher HCRU rates vs. patients in sustained remission, suggesting that achieving treat-to-target goals would reduce health care expenses.