The pathophysiology of osteoporosis complicating chronic liver disease is unknown. Some studies have found leptin to be a potent inhibitor of bone formation.

To investigate the relationship between leptin, osteocalcin and bone mineral density (BMD) in liver cirrhosis, sixty patients with liver cirrhosis were included in this study. They were classified into 3 groups; group I (20 premenopausal females), group II (20 postmenopausal females) and group III (20 males). Also, 21 age and sex matched healthy subjects (7 for each group) were included as control groups. The patients were classified also according to Child-Pugh classification into grade B (n=38) and grade C (n=22). Both patients and controls were subjected to: complete history, clinical examination, and calculation of body mass index. Serum osteocalcin, leptin and intact parathyroid hormone were measured; in addition to liver functions test, HBsAg, Anti-HCV, serum phosphorus, and calcium. BMD was measured by Calcaneal ultrasound.

            (BMD) was below normal in 86.6% of patients as a whole. The mean value of serum leptin was significantly elevated in all patient groups (I, II, III) when compared to their control group (P<0.01, P<0.001, and P<0.01 respectively). Also, it was significantly high in both female groups (I and II) versus males (group III), (P< 0.01 each). Also, mean values of BMD and serum osteocalcin were significantly decreased in each group compared to its control (P<0.001; P<0.01 in group I, P<0.05; P<0.001 in group II, and P<0.001; P<0.001 in group III respectively). In Child-Pugh grade C group, BMD and serum osteocalcin were significantly low (P<0.001, P<0.05 respectively), while serum leptin was significantly elevated (P<0.05), when compared to grade B group.

            Serum leptin was found to be negatively correlated with serum osteocalcin (r=-0.553; P<0.001), BMD (r=-0.229; P<0.05), albumin (r=-0.449; P<0.001), and A/G ratio (r=-0.661; P<0.001), while positive correlations were found between serum leptin with both AST(r=0.462; P<0.001), and ALT (r=0.483; P<0.001).

            Negative correlation between osteocalcin and intact parathyroid hormone (r=-0.370, P<0.001) was detected, while positive correlations were found between serum osteocalcin and BMD (r=0.418; P<0.001), albumin (r=0.659; P<0.001), and A/G ratio (r=0.444; P<0.001).

In conclusion: Serum leptin was elevated in cirrhotic patients in both gender but it is higher in females than males. There were inverse relationship between serum leptin and BMD and osteocalcin. Leptin may have a role in the pathogenesis of osteoporosis in liver cirrhosis.