Functional status in severe juvenile idiopathic arthritis in the biologic treatment era: an assessment in a French paediatric rheumatology referral centre

Objectives. To investigate the functional status of difficult-to-treat JIA patients, including patients receiving biotherapies, and to correlate functional status to disease activity. Methods. All JIA patients consecutively evaluated in a paediatric rheumatology referral centre (November 2008 to March 2009) were enrolled in an observational cross-sectional study. The Childhood HAQ (CHAQ), physician’s assessment of overall disease activity, parent’s assessment of well-being and pain, and active and limited joint numbers were measured. Results. We enrolled 95 patients [27% systemic, 29% polyarticular, 22% enthesitis-related arthritis (ERA) and 23% oligoarticular JIA]. Median disease duration was 3.5 years. Treatment included NSAIDs (56%), MTX (23%), CSs (21%) and biologics (45%). Of all patients, 31 and 56%, respectively, had inactive and minimally active disease. The median CHAQ score was 0.375 (range 03). Most patients had no or mild functional disability (61%), impaired well-being (63%) or pain (55%); 10% reported severely impaired function and well-being, 19% severe pain. ERA patients reported worse well-being and pain. CHAQ scores correlated with disease activity. Long-lasting disease and biologic treatment were associated with better well-being and pain scores. Conclusion. Despite the high proportion of severe JIA patients in this cohort, CHAQ values are within the lower range of recent reports, probably related to new therapeutic approaches. Impaired function and well-being remain a challenge for at least 10% of the patients. Impaired well-being and pain in ERA patients require further study. The strong correlation between functional status and well-being underlines the importance of improving function to optimize quality of life.