Exposure to air pollutants increased disease activity in childhood-onset systemic lupus erythematosus patients
Source: Arthritis Care Res
Fernandes E, Silva C, Braga A, Sallum A, Campos L, Farhat S; Arthritis Care and Research (Apr 2015)
OBJECTIVE: To investigate the association between exposure to air pollutants in the São Paulo metropolitan area and disease activity in childhood-onset systemic lupus erythematosus (C-SLE) patients.
METHODS: A longitudinal panel study was carried out based on 409 consecutive visits of C-SLE patients (ACR criteria) living in the São Paulo metropolitan area. Disease activity was evaluated according to Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K), and the patients were divided in two groups: SLEDAI≤8 and SLEDAI>8. Daily concentrations of inhaled particulate matter (PM10 ), sulfur dioxide (SO2 ), nitrogen dioxide (NO2 ), ozone (O3 ) and carbon monoxide (CO) were evaluated on the 31 days preceding the medical visits. A generalized estimation equation (GEE) model was used to assess the impact of these measurements on the SLEDAI-2K score, considering the fixed effects for repetitive measurements. The models were adjusted for erythrocyte sedimentation rate (ESR), corticosteroid use (prednisone use and cumulative dose of prednisone), antimalarials, immunosuppressive agents, presence of infection 20 days preceding the medical appointment, minimum temperature and relative humidity.
RESULTS: PM10 , NO2 and CO were risk factors for C-SLE activity (SLEDAI-2K>8) approximately two weeks after exposure. A 13.4 µg/m(3) increase in PM10 moving average (from lag 12 to lag 15) was associated to a 34% (95% CI 7.0-68.0) increase in the risk of SLEDAI-2K above 8.
CONCLUSION: This is the first study to identify that exposure to inhaled pollutants may increase the risk of disease activity in children with C-SLE in a large center. This article is protected by copyright. All rights reserved.