Understanding the biology and use of TNF therapy in jia-clinical outcomes

Results The study population included 18 (13%) extended oligoarticular, 17 (12%) RF+ Poly and 102 (75%) RFPoly JIA patients. At enrollment, age (mean/median/range) was 11.3/11.6/3.4-20.1 yrs; disease duration was 5.0/4.1/0.618.6 yrs; 103 (75%) were females and 64 (47%) were ANA +. Duration of CID at baseline was 1.2/0.5/1 day-12.1 yrs. Anti-TNF was etanercept in 106 (77%), 25 (18%) adalimumab and 6 (5%) infliximab. 40% were on MTX at baseline (mean/median dose 0.4/0.4 mg/kg/wk). 17% were unable to maintain CID for the first 6 months despite stable background medications. For the extended oligo, Poly RF – and Poly RF+ categories 94%, 82% and 60%, respectively, maintained CID for the first 6 months (chi-square 6.7, p 0.03). ANA status, MTX use, and type of anti-TNF were not associated with the ability to maintain CID (chi-square p values 0.48, 0.14, and 0.75, respectively). Upon stopping the anti-TNF therapy, the mean time to flare was 18.3 months with a median of 26 months (range 9-32 months). Longer disease duration at baseline was associated with an increasing risk of flare with stopping anti-TNF therapy (chi square 5.62, p = 0.017). Background MTX significantly decreased the risk of flare (p= 0.05) and significantly increased the time to flare (p = 0.05). JIA subtype was significantly associated with both risk of flaring (p=0.02) and time to flare (p= 0.04) with RF+ Poly flaring less frequently than either RFor Extended oligo which seem similar. RF+ patients were significantly less likely to flare than RF(p= 0.02). Age, gender, ANA status, duration of CID did not predict risk of or time to flare.