Treatment response to tumor necrosis factor inhibitors and methotrexate monotherapy in adults with juvenile idiopathic arthritis: Data from NORDMARD
Abstract
Objective Compare effectiveness of tumor necrosis factor inhibitors (TNFi) ± comedication and methotrexate monotherapy (MTX mono) between adult juvenile idiopathic arthritis (JIA) and rheumatoid arthritis (RA) patients.
Methods Adult JIA and RA patients were identified from the NOR-DMARD register. Disease activity measurements at baseline, 3, 6 and 12 months were compared between JIA and RA patients starting (1) TNFi and (2) MTX monotherapy, using age- and gender-weighted analyses. We calculated differences between JIA and RA in mean changes in DAS28, CDAI and SDAI, among other disease activity measures. DAS28, CDAI, SDAI and ACR/EULAR remission rates at 3, 6 and 12 months, as well as 6- and 12-month LUNDEX-corrected rates, were calculated.
Results We identified 478 JIA patients (TNFi/MTX mono N=358/120) and 4637 RA patients (N=2292/2345). JIA patients had lower baseline disease activity compared to RA patients across treatment groups. After baseline disease activity adjustment there were no significant differences in disease activity change from baseline to 3, 6 and 12-months follow-up between JIA and RA patients for either treatment group. 12- month remission rates were similar between groups based on DAS28 (TNFi: JIA 55.2%, RA 49.5%. MTX mono: JIA 45.3%, RA 41.2%) and ACR/EULAR remission criteria (TNF: JIA 20.4%, RA 20.0%. MTX mono: JIA 17.0%, RA 12.7%). Median drug survival (years) was similar for JIA and RA in both treatment groups (TNFi: JIA 1.2, RA 1.4; MTX mono: JIA 1.3, RA 1.6)
Conclusion TNFi and MTX mono are effective in adult JIA, with similar effectiveness as in RA.