Adolescent obesity, bone mass, and cardiometabolic risk factors

Abstract

Objective: To compare bone mass between overweight adolescents with and without cardiometabolic risk factors (CMR). Associations of bone mass with CMR and adiposity were also determined. Study design: Adolescents (aged 14 to 18 years) who were overweight were classified as healthy (n = 55), having one CMR (1CMR; n = 46), or having two or more CMR (≥2CMR; n = 42). CMRs were measured with standard methods and defined according to pediatric definitions of metabolic syndrome. Total body bone mass, fat mass, and fat-free soft tissue mass were measured with dual-energy X-ray absorptiometry. Visceral adipose tissue and subcutaneous abdominal adipose tissue were assessed with magnetic resonance imaging. Results: After controlling for age, sex, race, height, and fat-free soft tissue mass, the healthy group had 5.4% and 6.3% greater bone mass than the 1CMR and ≥2CMR groups, respectively (both P values <.04). With multiple linear regression, adjusting for the same co-variates, visceral adipose tissue (β = -0.22), waist circumference (β = -0.23), homeostasis model assessment of insulin resistance (β = -0.23), and high-density lipoprotein cholesterol level (β = 0.22) were revealed to be associated with bone mass (all P values <.04). There was a trend toward a significant inverse association between bone mass and fasting glucose level (P = .056). No relations were found between bone mass and fat mass, subcutaneous abdominal adipose tissue, blood pressure, or triglyceride level. Conclusion: Being overweight with metabolic abnormalities, particularly insulin resistance, low high-density lipoprotein cholesterol level, and visceral adiposity, may adversely influence adolescent bone mass.