Relationships between serum adipocyte hormones (adiponectin, leptin, resistin), bone mineral density and bone metabolic markers in osteoporosis patients

The purpose of this study was to investigate the relationship between fasting serum leptin, adiponectin and resistin levels and bone mineral density (BMD) in osteoporosis patients and a non-osteoporosis control group. We studied 81 non-diabetic osteoporosis patients (92 % female, 8 % male; mean age 54.5 +/- A 15.5 years and body mass index [BMI] 28.2 +/- A 4.6) and 120 non-diabetic individuals with normal BMD as controls (86 % female, 14 % male; mean age 39.7 +/- A 10.4 years and BMI 28.8 +/- A 4.4). BMD was studied by dual-energy X-ray absorptiometry from the lumbar spine (L1-L4) and femoral neck and fasting blood samples were taken for biochemical measurement of fasting blood glucose, leptin, adiponectin and resistin. Fasting levels of plasma adiponectin had a significant negative correlation with BMD of the femoral neck and lumbar spine in the osteoporosis group (r = -0.478, P = 0.003, r = -0.513, P = 0.023) but not in the non-osteoporosis group (r = -0.158, P = 0.057, r = -0.23, P = 0.465). Fasting plasma levels of resistin were significantly correlated only with femur BMD in the osteoporosis group, and not significantly correlated with lumbar spine BMD (r = -0.244, P = 0.048 vs r = 0.276, P = 0.56). Leptin did not have a significant correlation with BMD in either the osteoporosis or non-osteoporosis groups (P > 0.05). Adiponectin had a significant negative correlation with BMD of the lumbar spine and femoral neck. The correlation between leptin and resistin are not inconclusive.