Factors affecting bone mineral density in children and adolescents with secondary osteoporosis

Abstract

Purpose This study aimed to investigate the clinical factors associated with bone mineral density (BMD) among children and adolescents with osteoporosis secondary to treatment for underlying clinical conditions. Methods We retrospectively reviewed the medical records of patients aged 10–18 years and evaluated them for lumbar spine BMD (LSBMD) after treatment for underlying diseases, including hemato-oncologic, rheumatologic system, and inflammatory bowel diseases. LSBMD measured by dual-energy x-ray absorptiometry (DXA) performed from March 2019 to March 2021 was evaluated. We analyzed 117 patients who underwent initial DXA after treatment for underlying diseases. Results Subjects in this study had multiple underlying diseases: hemato-oncologic (78.6%), rheumatologic (11.1%), and inflammatory bowel diseases (10.3%). There was no significant association between the z-score and bone metabolic markers (P>0.05). However, higher cumulative glucocorticoid (GC) dose significantly reduced LSBMD z-score (P=0.029). Moreover, the association between cumulative dose of GC and initial z-score of LSBMD was significant in logarithmic regression analysis (P=0.003, R2=0.149). GC accumulation was a significant risk factor for vertebral fracture when the initial BMD was evaluated after treatment (P=0.043). Bone metabolic markers did not significantly influence the risk of vertebral fracture. Conclusions Initial bone mass density of the lumbar spine evaluated after long-term GC use for underlying diseases is a predictor of further vertebral fractures.

Keywords

• secondary osteoporosis
• bone mineral density
• dual-energy x-ray absorptiometry