Effect on lung function of methotrexate and non-steroid anti-inflammatory drugs in children with juvenile rheumatoid arthritis.

We evaluated lung function in a group of patients affected by juvenile rheumatoid arthritis (JRA), without clinical and/or radiological signs of respiratory involvement. We compared the effects on pulmonary function of methotrexate (MTX) therapy combined with non-steroid anti-inflammatory drugs (NSAIDs) to those of NSAIDs alone and correlated lung function to subtype onset, disease duration and disease activity. Our patients were 27 JRA children, subdivided into two groups according to the therapy (group A = 14 patients, treated with a low dose of MTX and NSAIDs; group B = 13 patients, treated with NSAIDs alone). Clinical evaluation, haematological data and pulmonary function tests (PFTs) were obtained in each group at baseline (time 0) and at 1 year (time 1). At time 0 and time 1 PFTs were altered in 51.8% of JRA patients. The restrictive pattern (reduced forced vital capacity, FVC) was the most frequent feature, observed in 22.2% of patients. In group A the mean values of FVC, FEV1 (forced expiratory flow in 1 s), FRC (functional residual capacity), TLC (total lung capacity) and DLCO (diffusing lung capacity of carbon monoxide) were significantly lower compared to those of group B, at time 0 and at time 1. No functional parameter was correlated to subtype, duration or activity of the disease. Our study confirms that abnormalities in PFTs may be detected in JRA patients, even in the absence of clinical and/or radiological signs of lung disease; MTX in combination with NSAIDs does not seem to affect lung function at 1 year more than NSAIDs alone.