Factors related to decreased bone mineral density in childhood cancer survivors

The risk of osteoporosis or osteopenia is known to increase after childhood cancer treatment. The purpose of this study was to evaluate patterns of bone mineral density (BMD) and to identify factors related to the decreased BMD in childhood cancer survivors. We studied 78 patients (34 boys, 44 girls) treated for childhood cancer. Twenty (25.7%) patients had lumbar BMD (LBMD) standard deviation score (SDS) lower than -2. Nineteen (24.4%) patients had femur neck BMD (FNBMD) SDS lower than -2. The patients treated with hematopoietic stem cell transplantation had lower LBMD SDS (-1.17±1.39 vs -0.43±1.33, P=0.025). The risk of having LBMD SDS<-2 was higher in the patients treated with glucocorticoid (GC) for graft-versus-host disease (GVHD) (36.6% vs 13.5%; odds ratio [OR], 3.7; P=0.020). In multivariate logistic regression analysis, longer duration of GC treatment for GVHD (OR, 1.12; 95% confidence interval [CI], 1.05-1.20) and lower body mass index (BMI) SDS (OR, 0.59; 95% CI, 0.36-0.95) were associated with decreased LBMD SDS. These findings suggest that prolonged GC use and reduction in BMI are risk factors for decreased BMD in childhood cancer survivors. Anticipatory follow-up and appropriate treatment are necessary, especially for the patients with risk factors.