Effectiveness and Safety of Treat-to-target Strategy for Methotrexate-Na?ve Rheumatoid Arthritis Patients >75 Years of Age

Objectives To identify differences in effectiveness and safety of a treat-to-target (T2T) strategy comparing late-onset MTX-na & iuml;ve RA patients (LORA) >= 75 or <75 years of age. Methods Treatment was adjusted to target low disease activity with conventional synthetic DMARDs followed by biologic DMARDs (bDMARDs) in LORA >= 75 years (n = 98, mean age 80.0 years) and LORA <75 years (n = 99) with moderate-high disease activity. Achievement of Simplified Disease Activity Index (SDAI) remission at week 156 by non-responder imputation analysis was evaluated as a primary outcome. Results LORA >= 75 years had more comorbidities than LORA <75 years, but SDAI and ACPA positivity were similar at baseline. Of the LORA >= 75 years, 70.4% started MTX and 34.1% and 37.1% received a bDMARD at week 52 and 156, respectively (very similar to the LORA <75 years). Glucocorticoid use was more frequent in the LORA >= 75 years than in the LORA <75 years. Comorbidities/adverse events more frequently contributed to the reasons for non-adherence to T2T in the LORA >= 75 than in the LORA <75. At week 156, 32.7% of the LORA >= 75 and 66.7% of the LORA <75 achieved SDAI remission (P < 0.001). The cumulative incidence of serious adverse events (SAEs) over 156 weeks was 42.8% in the LORA >= 75 and 22.1% in the LORA <75. Multivariable analysis indicated an increased risk of SDAI non-remission at week 156 in the LORA >= 75 [odds ratio 2.82 (95% CI 1.29. 6.14)] after adjusting for comorbidities at baseline, non-adherence to T2T and SAEs. Conclusions It was more difficult to achieve remission in the LORA >= 75 patients than in the LORA <75 patients due to both poor treatment response and safety issues.