Is there any association between leptin levels and bone mineral density in haemophiliac men?

Conflicting data exist regarding the role of leptin in bone metabolism. The purpose of the present study was to investigate serum leptin concentrations in male patients with haemophilia A and B, a disease known to be associated with low bone mass. Eighty-one male patients, aged 45.4 ±15 years, were screened. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) in lumbar spine (LS), femoral neck (FN) and total hip (TH). Low bone mass was diagnosed in 20 patients (24.7%). Serum leptin concentrations were strongly associated with body weight (r s = 0.457, p = 0.0001) and body mass index (BMI) (r s = 0.491, p = 0.0001). In unadjusted analysis leptin was inversely associated with BMD in LS (r s = -0.255, p = 0.023), but not in FN and TH (r s = -0.205, p = 0.068 and r s = -0.191, p = 0.090, respectively). However, after adjusting for BMI and body weight, leptin was inversely associated with BMD in FN (F 1,76 = 7.727, p = 0.007, β = -0.371, ΔR (2) = 0.089) and TH (F 1,76 = 4.533, p = 0.036, β = -0.290, ΔR (2) = 0.054), but not in LS (F 1,75 = 2.076, p = 0.154, β = -0.202, ΔR (2) = 0.026). No association was found between age, presence of HBV, HCV or HIV infection or alkaline phosphatase and leptin levels. Our study showed a negative association between circulating leptin levels and bone mass in males, independently of body weight and BMI.