Bone metabolism biomarkers, body weight, and bone age in healthy Brazilian male adolescents

Eighty-seven male volunteers were grouped according to bone age (BA): 10–12 years (n=25), 13–15 years (n=36), and 16–18 years (n=26), and the following were recorded for each: weight (kg), height (m), BMI (kg/m ), calcium intake from three 24-h food recalls (mg/day), puberty evaluation by Tanner stages, bone biomarker (BB) evaluation, serum osteocalcin (OC), bone alkaline phosphatase (BAP), carboxyterminal telopeptide (S-CTx), and bone mineral density (BMD) evaluations by dual-energy X-ray absorptiometry (g·cm ) in the lumbar spine, proximal femur, and the whole body. BBs showed similar behaviors, and very high median values were observed for individuals aged 13–15 years (BAP=155.50 IU/L, OC=41.63 ng/mL, S-CTx=2.09 ng/mL). Lower median BB values were observed with advancing BA between 16 and 18 years (BAP=79.80 IU/L, OC=27.80 ng/mL, S-CTx=1.65 ng/mL). Stepwise multiple regression analysis showed body weight associated with BA as independent variables with greater determination power for S-CTx (r =0.40) and OC (r =0.21). For BAP, stepwise analysis showed body weight and whole-body BMD (r =0.34). All predictive models showed significance (p