Methotrexate for treating juvenile idiopathic arthritis

In both adult rheumatoid arthritis (RA) and juvenile arthritis, the focus has shifted from 'inflammation parameters' to more patient centered disability outcomes. In RA this resulted in the development of the Outcome Measures in Arthritis Clinical Trials (OMERACT), and in juvenile arthritis the Pediatric Rheumatology International Trials Organization (PRINTO) core set. This PRINTO-core set was established using a combination of statistical and consensus formation techniques. This core set contains a number of patient centered disability measures. This review systematically searched the available literature and reports the available evidence of efficacy of MTX, with special focus on patient centered disability measures in Juvenile Idiopathic Arthritis (JIA).

To perform a systematic review on the effects of MTX on functional ability, range of motion, quality of life, overall well-being and pain for patients with JIA.

The Cochrane Controlled Trials Register (CCTR) and MEDLINE were searched up to March 2001, using the search strategy sensitive for randomised controlled trials, used by the Cochrane Collaboration.

Randomized controlled trials and controlled clinical trials comparing MTX against placebo or standard care in patients with Juvenile Idiopathic Arthritis (JIA) were selected.

Two reviewers (TT, JN) determined the studies to be included in this review and extracted the data of patient centered disability measures. The data were pooled using standardized mean differences (SMD) for limited joint range score, number of joints with swelling. The number of joints with pain on motion were evaluated using weighted mean differences (WMD). Physicians global assessment, parents global assessment and withdrawals due to efficacy and side effects were evaluated with pooled odds ratios (OR).

Only two studies with a total 165 JIA patients under 18 years of age were included in this review. For JIA patients, MTX therapy had small to moderate effects on patient centered disability outcomes. The effect on joint range of motion, number of joints with pain and swelling and physician's and parent's assessment of disease activity showed a relative percentage improvement from 3 to 23% greater with MTX than with placebo.

Current evidence suggests that MTX does have minimal clinically significant effects (>20%) on patient centered disability measures in JIA patients.