Influence of the weight status on hip bone mineral density in young males

Abstract

Objective The aim of this study was to explore the effects of being obese or overweight on bone mineral density (BMD) of proximal femur in a group of Lebanese adolescent boys and young men (aged 15 to 30 years). Material and methods This study included 128 adolescent boys and young men (34 obese, 54 overweight and 40 normal-weight). The three groups (obese, overweight and normal-weight) were matched for age. Body composition and proximal femur BMD were assessed by dual-energy X-ray absorptiometry (DXA). DXA scans were analyzed at the femoral neck (FN) by the hip structure analysis (HSA) program. Cross-sectional area (CSA), an index of axial compression strength, and section modulus (Z), an index of bending strength, were measured from hip bone mass scans. Daily calcium intake and physical activity were assessed using questionnaires. Results Body weight, lean mass, fat mass and BMI were significantly higher in obese and overweight subjects in comparison to normal-weight subjects (P < 0.05). After adjusting for age, whole body bone mineral content (WB BMC), total hip (TH) BMD, FN BMD, FN CSA and FN Z were significantly higher in obese and overweight subjects in comparison to normal-weight subjects (P < 0.05). After adjusting for weight, obese subjects displayed lower WB BMC, FN CSA and FN Z in comparison to normal-weight and overweight subjects (P < 0.05). In the whole population, weight, height, lean mass and physical activity were positively correlated to WB BMC, TH BMD, FN BMD, FN CSA and FN Z. Conclusion This study suggests that in obese adolescent boys and young men, WB BMC and indices of axial compression strength and bending strength at the FN are not adapted to the increased body weight.