Bone Abstracts

Leptin and adiponectin have an opposing relationship in circulation; leptin is higher and adiponectin lower in overweight/obese individuals, and vice versa. Studies showed that both leptin and adiponectin can be either beneficial or harmful to bone depending on the mode of action. The objective was to investigate the association of serum leptin:adiponectin ratio (L:A) with BMD of various skeletal sites and markers of bone turnover in overweight and obese postmenopausal women. Participants included (n=184) healthy Caucasian women (BMI range=25.0–40.0 kg/m², age=55.7±4.4 years, mean±S.D.). BMD was assessed by iDXA. Serum leptin, adiponectin and bone markers (osteocalcin, serum NTx and urine CTx) were analyzed with immunoassay kits. The data were analyzed by SPSS, calculating Pearson’s correlations and multiple regression models controlling for multiple confounders, including age, physical activity, years since menopause, dietary calcium and vitamin D intake, as well as lean, fat tissue and/or BMI. Results showed that serum L:A was significantly positively correlated with BMD at femoral neck, total femur and forearm before and after controlling for the above confounders. Multiple regression, with serum L:A as independent variable, revealed that it is positively related to both femoral neck and total femur BMD (before and after controlling for above confounders). There was no significant relationship between L:A and any of the bone markers. In conclusion, higher L:A affects BMD at some skeletal sites. The influence may be site-specific and probably driven by the higher leptin levels reflecting higher overweight status.