Investigating the Prevalence of Low Bone Mass in Children of Southern Iran and Its Associated Factors

Evaluation of Bone Mineral Density in Juvenile Systemic Lupus Erythematosus

Objectives

The present study aimed to determine the prevalence of low bone mineral density (BMD) and low bone mineral content (BMC) as chronic complications of juvenile systemic lupus erythematosus (JSLE) and identify the associated variables and patient characteristics to investigate the relationship between BMD and influential factors.

Methods

This cross-sectional study enrolled 54 patients with JSLE, including 38 females and 16 males. The BMD and BMC were assessed by dual-energy X-ray absorptiometry in the hip (femoral neck) and the lumbar spine. Low BMD was considered a Z-score < -2. The study investigated the association of BMC and Z-score with the current daily dose of corticosteroids, the daily dose of corticosteroids at disease onset, the duration of disease, the duration of steroid treatment, the time from the onset of symptoms to diagnosis, and renal involvement.

Results

The prevalence of low BMD in the lumbar spine and the femoral neck was 14.8% and 18.5%, respectively; the reduction of BMD was more significant in the femoral neck compared to the lumbar spine. Osteoporosis was detected in one patient. The multiple linear regression analysis found a significant association between a higher daily corticosteroid dose and lower BMC of the femoral neck and the lumbar spine. In addition, patients receiving higher doses of corticosteroids at disease onset showed better follow-up bone mineral densitometry results.

Conclusion

Based on the findings of this study, JSLE more affects the femoral neck than the lumbar spine. Patients receiving a more robust treatment with higher doses of corticosteroids at disease onset (to control the inflammatory processes) showed better spinal BMC results. A higher dose of daily corticosteroid treatment during assessment was identified as a risk factor for low BMD.