Association of Lean and Fat Body Mass, Bone Biomarkers and Gonadal Steroids with Bone Mass during Pre- and Midpuberty

Abstract

Background/Aims: The association of bone mass with body composition, bone turnover markers and gonadal steroids was examined in Hungarian children during pre- and midpuberty. Methods: Two hundred and thirty-seven 7- to 16-year-old subjects (56% girls) were investigated. Bone mineral density (BMD), fat mass and total and appendicular lean mass were estimated with dual-energy X-ray absorptiometry (Lunar Prodigy). The fat mass index and appendicular lean mass index (LMI) were calculated. Serum bone markers, parathyroid hormone, estradiol and testosterone were analyzed. Associations between variables were evaluated by multiple regression analysis. Results: During prepuberty, bone biomarkers, gonadal steroids and appendicular LMI were associated with bone mass in both genders (p < 0.05). During midpuberty, girls’ bone turnover markers were negatively associated with bone mass (p < 0.001). In prepuberty, appendicular LMI and β-crosslaps were predictors of bone mass in both genders. During midpuberty, appendicular LMI and gonadal steroids positively contributed to bone mass in both genders, while osteocalcin exerted a negative influence on total and L1–L4 spine BMD in girls and on L1–L4 BMD in boys (all p < 0.001). Conclusions: Predictors for bone development varied according to Tanner stage and gender. The most significant determinants of bone mass were appendicular LMI and estradiol.

Bone formation and resorption markers at 7 years of age: Relations with growth and bone mineralization

“…These findings are consistent with the premise that bone markers reflect instantaneous metabolic activity and do not directly translate physical dimensions that result from the cumulative process of bone gain throughout several years [6]. In prepubertal children, some previous studies have also found no relationship between tALP, OC or β-CTx and whole body (WB) and LS BMC or BMD [14, 15, 35]. Other studies disclosed, however, consistent positive relationships between tALP and OC and WB and LS BMC, in boys [16] and between OC and CTX and WB and LS BMC/BMD, in both sexes [15, 17].…”

“…Other studies disclosed, however, consistent positive relationships between tALP and OC and WB and LS BMC, in boys [16] and between OC and CTX and WB and LS BMC/BMD, in both sexes [15, 17]. In older pubertal children, inverse correlations between serum OC or CTX and BMD were disclosed [9, 15], which is expected because, during puberty, bone turnover decreases with advancing sexual maturation while, at the same time, bone mass accrual continues up to peak bone mass [7]. Some authors have also described site-specific associations between bone metabolism markers and bone mass during puberty, disclosing stronger relationships in anatomical sites with more trabecular bone (e.g.…”

“…In prepubertal children, some previous studies have also found no relationship between tALP, OC or β-CTx and whole body (WB) and LS BMC or BMD [14, 15, 35]. Other studies disclosed, however, consistent positive relationships between tALP and OC and WB and LS BMC, in boys [16] and between OC and CTX and WB and LS BMC/BMD, in both sexes [15, 17]. In older pubertal children, inverse correlations between serum OC or CTX and BMD were disclosed [9, 15], which is expected because, during puberty, bone turnover decreases with advancing sexual maturation while, at the same time, bone mass accrual continues up to peak bone mass [7].…”

The impact of excess body fat on bone remodeling in adolescents

“…The results confirmed data in the literature on this bone marker [24] obtained for Korean children, showing that the higher the excess weight, the lower the level of osteocalcin. The significant and negative correlations between FM and the three bone biomarkers found in the present study in girls may reflect the complex interaction between bone biomarkers, bone mass and gonadal steroids during puberty [25]. These authors observed differences in the association between bone mass and osteocalcin when the pre-and mid-pubertal periods were compared, with the observation of an inverse relationship only in mid-puberty.…”

“…These authors observed differences in the association between bone mass and osteocalcin when the pre-and mid-pubertal periods were compared, with the observation of an inverse relationship only in mid-puberty. Another interesting result was related to the strength of the correlation between osteocalcin and total body bone mass, with an r value of −0.60 in eutrophic girls, while eutrophic boys had a correlation of −0.07 [25]. These results indicate differences in the magnitude of the impact of bone mass between sexes.…”