To compare the 1-year retention rates of anti-tumor necrosis factor alpha (anti-TNFalpha) medications in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) with complementary analyses of the effect on health status.
Our analyses comprised 847, 172, and 249 anti-TNFalpha treatment courses in patients with RA, PsA, and AS, respectively. Crude drug survival was compared and hazard ratios (HRs) for treatment termination were calculated with adjustments for age, sex, investigator's global assessment, and concomitant methotrexate (MTX). Adjusted changes in health-related quality of life (HRQOL) were compared among the groups.
Unadjusted 1-year retention rates were 65.4%, 77.3%, and 77.5% in the RA, PsA, and AS groups, respectively. The adjusted HRs for treatment termination were 0.76 (95% confidence interval [95% CI] 0.53-1.07) for PsA versus RA and 0.66 (95% CI 0.47-0.92) for AS versus RA. High baseline disease activity and female sex were significantly associated with premature treatment termination, whereas concomitant MTX was associated with better drug survival. However, the impact of MTX was apparent for RA and PsA, but not for AS in stratified analyses. The improvements in HRQOL were superior in patients with PsA and AS compared with RA.
Our results suggest that survival of anti-TNFalpha treatment is superior in AS and PsA patients compared with RA patients. Larger improvements in HRQOL in patients with spondylarthritides may contribute to the differences in drug survival. Concomitant MTX was associated with better retention rates in RA and PsA patients, but not AS patients.