Association among serum fetuin-A level, coronary artery calcification, and bone mineral densitometry in maintenance hemodialysis patients.

Patients with end-stage renal disease have a very high prevalence and extent of arterial calcification. A number of studies suggest that similar pathophysiologic mechanisms are responsible for development and progression of calcification of atherosclerotic plaque and bone formation. Fetuin-A is a potent calcification inhibitor and is expressed in bone, with not-yet well-defined functions. The aim of this study was to investigate the relation between bone mineral densitometry parameters, coronary artery calcification, and serum fetuin-A levels. In a cross-sectional design, we included 72 maintenance hemodialysis (HD) patients and 30 age- and gender-matched healthy controls. Serum fetuin-A levels were studied both in maintenance HD patients and healthy controls. Maintenance HD patients had radius, hip, and lumbar spine bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry and coronary artery calcification score (CACS) measured by electron-beam computed tomography. The associations between site-specific BMD parameters, CACS, and serum fetuin-A levels were studied in maintenance HD patients. CACS, mass, and volume of plaques in coronary arteries were significantly higher in patients with a T-score below -2.5 than above in the proximal region of the radius, neck and trochanter of the femur, and the lumbar spine. Mean serum fetuin-A concentration was 0.636 +/- 0.118 g/L in maintenance HD patients and it was less than healthy controls (0.829 +/- 0.100 g/L, P < 0.0001). CACS, mass, and volume of plaques in coronary arteries correlated significantly with the serum fetuin-A levels. Moreover, significant positive correlations were shown between the serum fetuin-A levels, BMD values, and T-scores of proximal radius, neck, and trochanter of the femur, but not with the lumbar spine. The present study demonstrates an association between serum fetuin-A levels, coronary artery calcification, and bone mineral densities--except for the lumbar spine, in maintenance HD patients. However, the results should be interpreted with caution because of the cross-sectional design of the study.