Hepatic fat content and bone mineral density in children with overweight/obesity

OBJECTIVES: To examine the influence of non-alcoholic fatty liver disease (NAFLD) and hepatic fat content on bone mineral density (BMD), and to investigate whether the relationship between NAFLD and BMD is independent of lifestyle factors related to BMD. METHODS: Hepatic fat content (magnetic resonance imaging), BMD, lean mass index, total and abdominal fat mass (dual-energy-X-ray absorptiometry), moderate to vigorous physical activity (MVPA) (accelerometry), and calcium and vitamin D intake (two 24 h recalls) were measured in 115 children with overweight/obesity aged 10.6 +/- 1.1 years old. RESULTS: Children with NAFLD had lower BMD than children without NAFLD regardless of sex, puberty stage, lean mass index, fat mass, MVPA, and calcium and vitamin D intake (0.89 +/- 0.01 vs. 0.93 +/- 0.01 g/cm(2) for NAFLD and non-NAFLD, respectively, P < 0.01). Higher hepatic fat content was significantly associated with lower BMD regardless of confounders (adjusted P < 0.05). CONCLUSIONS: Findings of the current study suggest that hepatic fat accumulation is associated with decreased BMD independently of adiposity, and regardless of those lifestyle factors closely related to bone mineral accrual in children. These results may have implication in the clinical management of children with overweight/obesity given the high prevalence of pediatric NAFLD.