Inverse relationship between circulating levels of leptin and bone mineral density in chronic liver disease.

Background and Aim: The pathophysiology of osteoporosis complicating chronic liver disease is unknown. Recent animal studies have found leptin to be a potent inhibitor of bone formation. The aim of this study was to investigate the relationship between serum leptin levels and bone mineral density in patients with chronic liver disease. Methods: Fifty-eight patients, 39 females and 19 males, and age- and gender-matched controls were included. Bone mineral density was measured by using dual energy X-ray absorptiometry. Serum leptin was measured by using a radioimmunoassay. Results: The mean serum leptin concentration was 10.4+/-11.3 and 15.2+/-17.9 ng/mL; P=0.11, in the patients and controls, respectively. Leptin correlated positively with body mass index in patients (r=0.40; P=0.003) and in controls (r=0.55; P<0.0001). In patients classified as Child-Pugh grade B and C, serum leptin correlated negatively with bone mineral density in females at both the lumbar spine and the femoral neck (r=-0.78; P=0.04 and r=-0.86; P=0.03, respectively). In male patients, the correlation was only significant at the lumbar spine (r=-0.99; P=0.002 and r=-0.86; P=0.06, at the lumbar spine and femoral neck, respectively). No correlation was found between serum leptin and bone mineral density in the controls. Conclusion: An inverse relationship between serum leptin and bone mineral density was found in patients with advanced chronic liver disease. The reasons for these findings are uncertain, but a pathophysiological role of circulating leptin in osteoporosis in chronic liver disease is possible. (C) 2001 Blackwell Science Asia Pty Ltd.