Background Biological disease modifying antirheumatic drugs (bDMARD) had great impact on the medical management of patients with juvenile idiopathic arthritis (JIA). Many patients nowadays enter adulthood in clinical remission, with normal function and without long-term sequelae. There is little information to what extent the early use of bDMARDs affects the long-term outcome of patients with JIA.
Objectives To investigate if the 10-year outcome after JIA onset is associated with the time lag between JIA disease onset and first bDMARD use.
Methods Outcome variables were examined in patients prospectively observed in the national JIA biologic register BiKeR and its follow-up register JuMBO since initiation a bDMARD therapy. Analyses included patients with at least one visit in JuMBO. Assessed parameters were JADAS3–10, C-HAQ, joint surgery (replacements, synovectomies), eye surgery and patient-reported outcomes. To analyze the influence of the time lag between JIA onset and first use of bDMARD, patients were assigned to one of the following three groups (G1: ≤2 year = early therapy, G2: intermediate, G3: ≥5 years = late). A general propensity score was estimated to adjust for baseline differences between the three groups. Mixed models were used to determine the association of the three groups and outcomes. Surgeries were analyzed by Cox regression analyses.
Results 609 patients were ever treated with a bDMARD and successfully transferred to JuMBO. Most (91%) patients were enrolled in BiKeR on etanercept followed by adalimumab (6%), 93% had previously received a conventional synthetic (cs) DMARD. 27.9% had RF negative polyarthritis and 19.5% enthesitis-related arthritis. The first csDMARD was started 0.4 years after disease onset in the early bDMARD group (n=142), and 1.2 and 3.1 years after JIA onset in the in-between group and late group (n=274), respectively. At their last follow-up (10.2±6.2 years after JIA onset), the patients' mean age was 21.2 years. The clinical outcome 10 years after disease onset could be investigated in 478 patients. Patients with early biologic treatment were significantly more often in drug-free JADAS remission (15%) for at least 12 months, had more often an inactive disease (JADAS3–10≤1, 27.6%) and no functional limitations (58.6%) compared to late treatment start. There was no significant difference in the patient-reported outcome measures. Among all 609 patients, 35 (5.8%) patients had undergone joint replacement, 100 (16.4%) synovectomy and 19 (3.2%) eye surgery. Patients on bDMARD in follow-up had a lower likelihood for joint replacement (HR=0.25, p=0.003) or synovectomy (HR=0.26, p<0.001). Patients with late DMARD treatment had significantly more synovectomies (HR=4.9, p<0.001) than patients with early treatment.
Conclusions Patients who started with cs and bDMARDs within the first two years of disease are significantly more often in drug-free remission in adulthood and have less sequelae than those who started later. The data emphasize the importance of a fast disease activity control and may support the idea of a window of opportunity for JIA.
Disclosure of Interest None declared