ABSTRACT
The pathophysiology of osteoporosis in complicated liver cirrhosis is unknown. Some studies have found leptin to be a potent inhibitor of bone formation. The study was performed to investigate the relationship between leptin, osteocalcin and bone mineral density in liver cirrhosis. Sixty patients with liver cirrhosis classified into 3 groups were included in this study. Group I included 20 premenopausal females, group II included 20 postmenopausal females and group III included 20 males. 30 healthy subjects with age and sex matched [10 for each group] were the control of this study. The patients and controls were subjected to history, clinical examination and measurements of body mass index [BMI]. The following investigations were performed; serum osteocalcin, leptin and intact parathyroid hormone in addition to liver function tests, liver biopsies, HBs-AG, HCV-Ab, serum phosphorus, and calcium and measurements of bone mineral density [BMD] by Calcaneal ultrasound. BMD was below normal in 86.6% of patients as a whole, their values were significantly lower in each group when compared to their controls [p<0.01, for all] and significantly lower in-group I than group II and in-group III than group II [p<0.01, for all]. Serum levels of leptin were significantly increased in each group when compared to their controls [p<0.01, for all] and significantly lower in-group III [males] than other groups [females] [p<0.01]. Serum osteocalcin levels were significantly lower in each group when compared to their controls [p<0.01, for all], but no significant differences were found among all three groups. Serum iPTH levels were elevated above normal range in 55% of patients but there was no significant difference between patient groups and their controls, and their levels were significantly lower in-group I when compared to other groups [p<0.01, for all]. There were no significant differences in serum levels of calcium and phosphorus between patient groups and their controls and among patient groups. In Child-Pugh's classification, BMD and serum osteocalcin were significantly lower in grade C than grade B [p<0.01], while serum leptin was significantly higher in grade C than grade B [p<0.01], but no significant differences in serum levels of iPTH, calcium and phosphorous were found between grade C and grade B. Serum levels of osteocalcin correlated with iPTH [r= -0.530], serum leptin [r=-0.654], BMD [r=0.580], serum calcium [r=0.530] and serum albumin [r=0.547]. Serum leptin correlated with osteocalcin [r=-0.654], BMD [r=-0.586] and serum albumin [r=-0.560].Serum leptin was elevated in cirrhotic patients in both genders, 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