Bone turnover in long-term survivors of childhood acute lymphoblastic leukemia

Background: We investigated the effects of demographic, lifestyle (self-reported smoking status and physical activity levels), cancer-related treatment factors (radiation and chemotherapy), and diet (calcium and vitamin D intake) on bone turnover and the relationship of bone turnover to lumbar spine bone mineral density (BMD) Z-scores (LS-BMD Z-scores) determined by quantitative computed tomography (QCT) in 418 ≥5-year survivors of childhood acute lymphoblastic leukemia (ALL). Procedure: Bone turnover was assessed by biomarkers including serum bone-specific alkaline phosphatase (BALP), osteocalcin (OC), and urinary N-telopeptide of type I collagen indexed to creatinine (NTX/Cr). The 215 males ranged in age from 9 to 36 years (median age 17 years). Results: Age and tanner score were inversely associated with all biomarkers (BALP, OC, NTX/Cr) (P<0.001). Males had higher BALP and OC than females (P<0.001). Body mass index (BMI) was inversely associated with OC and NTX/Cr (P<0.001). There was no significant association of biomarkers with lifestyle related factors, ALL treatment-related factors, dietary calcium, vitamin D, or LS-BMD Z-score. Conclusions: In this population of long-term survivors of ALL, bone turnover was significantly associated with age, gender, tanner stage, and BMI. ALL-related treatments did not influence bone turnover and bone turnover was not predictive of volumetric LS-BMD Z-score.