Bone mineral density in children wth systemic lupus erythematosus and juvenile rheumatoid arthritis
ABSTRACT Background: Although there is increasing interest in bone metabolism in patients with rheumatic disorders, few data exist on bone mineral density (BMD) in children with rheumatic disorders or on the association of BMD with disease-related variables. We determined BMD in Iranian children with systemic lupus erythematosus (SLE) and juvenile rheumatoid arthritis (JRA) to evaluate the relationship between disease-related variables and BMD. Patients and Methods: Twenty patients (13 girls and 7 boys) with SLE (n=15) and JRA (n=5) with a mean age of 13.10±3.29 years (range, 6-17 years), attending a pediatric rheumatology clinic and 20 healthy controls (matched for age and sex with each patient) were enrolled in a cross-sectional study between 2001 and 2003. BMD (g/cm 2 ) of the femoral neck (BMD-F) and lumbar vertebrae (BMD-L) were measured by dual energy X-ray absorptiometry (DEXA). The correlation between BMD and cumulative dose of steroids, daily dose of steroid, disease duration, disease activity, height, weight, and age was investigated. Results: BMD in the patients (BMD-F=0.72±0.15, BMD-L=0.70±0.19) was significantly lower than controls (BMD-F=0.95±0.17, BMD-L=0.98±0.20, P< 0.001). The severity of decreased BMD was more prominent in lumbar vertebrae than the femoral neck (P= 0.04). None of the variables were consistently related to a decrease in BMD. Conclusion: BMD was significantly lower in patients compared with controls. It was more prominent in lumbar vertebrae (trabecular bone). Although cumulative dose of steroids and disease duration appeared to have some influence on BMD, none were independently correlated with BMD.
Article: Prevalent vertebral fractures among children initiating glucocorticoid therapy for the treatment of rheumatic disorders.[show abstract] [hide abstract]
ABSTRACT: Vertebral fractures are an under-recognized problem in children with inflammatory disorders. We studied spine health among 134 children (87 girls) with rheumatic conditions (median age 10 years) within 30 days of initiating glucocorticoid therapy. Children were categorized as follows: juvenile dermatomyositis (n = 30), juvenile idiopathic arthritis (n = 28), systemic lupus erythematosus and related conditions (n = 26), systemic arthritis (n = 22), systemic vasculitis (n = 16), and other conditions (n = 12). Thoracolumbar spine radiograph and dual x-ray absorptiometry for lumbar spine (L-spine) areal bone mineral density (BMD) were performed within 30 days of glucocorticoid initiation. Genant semiquantitative grading was used for vertebral morphometry. Second metacarpal morphometry was carried out on a hand radiograph. Clinical factors including disease and physical activity, calcium and vitamin D intake, cumulative glucocorticoid dose, underlying diagnosis, L-spine BMD Z score, and back pain were analyzed for association with vertebral fracture. Thirteen vertebral fractures were noted in 9 children (7%). Of these, 6 patients had a single vertebral fracture and 3 had 2-3 fractures. Fractures were clustered in the mid-thoracic region (69%). Three vertebral fractures (23%) were moderate (grade 2); the others were mild (grade 1). For the entire cohort, mean +/- SD L-spine BMD Z score was significantly different from zero (-0.55 +/- 1.2, P < 0.001) despite a mean height Z score that was similar to the healthy average (0.02 +/- 1.0, P = 0.825). Back pain was highly associated with increased odds for fracture (odds ratio 10.6 [95% confidence interval 2.1-53.8], P = 0.004). In pediatric rheumatic conditions, vertebral fractures can be present prior to prolonged glucocorticoid exposure.Arthritis care & research. 04/2010; 62(4):516-26.