Factors Affecting Bone Mineral Density in Children and Adolescents with Systemic Lupus Erythematosus

Patients with juvenile-onset systemic lupus erythematosus (JSLE) are at a high risk of entering adulthood with disease-related morbidities such as reduced bone mass and osteoporosis. This study aimed to evaluate the clinical characteristics of JSLE and to analyze the factors associated with low bone mineral density (BMD) in these patients.Children and adolescents diagnosed with JSLE at a single hospital in Korea were included. Demographic, clinical, and laboratory data and use of glucocorticoids and disease-modifying anti-rheumatic drugs were collected. Lumbar spine BMD Z-score was measured using dual energy x-ray absorptiometry, and lumbar spine radiographic data were collected.A total of 29 patients with JSLE were included in this study. Of these patients, seven had a lumbar spine Z-score of -2.0 or lower and were designated as the low BMD group. The differences in the clinical parameters and treatment variables between the low BMD and non-low BMD groups were compared. Higher cumulative glucocorticoid dose, longer glucocorticoid exposure, and higher cumulative hydroxychloroquine dose were associated with low BMD; the main factor was the duration of exposure. There was no significant correlation between BMD and clinical profile, SLE disease activity, or bone metabolism markers.The duration of glucocorticoid exposure, cumulative glucocorticoid dose, and cumulative hydroxychloroquine dose were risk factors for low BMD in patients with JSLE, with the main factor being duration of glucocorticoid exposure. Thus, patients with JSLE should be routinely monitored for low BMD and potential fracture risks, and glucocorticoid-sparing treatment regimens should be considered.