Fibroblast Growth Factor 23 and Fetuin A are Independent Predictors for the Coronary Artery Disease Extent in Mild Chronic Kidney Disease

BACKGROUND AND OBJECTIVES: Cardiovascular disease in chronic kidney disease (CKD) is explained in part by traditional cardiovascular risk factors; by uremia-specific factors; and by abnormalities of mineral metabolism, factors involved in its regulation, and in the vascular calcification process. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In an unselected population of 177 patients with calculated GFR (eGFR) between 90 and 30 ml/min per 1.73 m(2), the link between the mineral metabolism abnormalities (calcium, phosphorus, calcium-phosphorus product), regulatory factors (parathyroid hormone [PTH], intact PTH [iPTH], vitamin D, fibroblast growth factor 23 [FGF 23], and fetuin A), and the severity of coronary artery disease (CAD) assessed by coronary angiography were evaluated in three subgroups defined by tertiles of Gensini lesion severity score. RESULTS: The mean serum values for FGF 23 in the entire study population was 28.1 ± 17.3 RU/ml and for fetuin A was 473.1 ± 156.2 μg/ml. Patients with eGFR < 60 ml/min per 1.73 m(2) had significantly higher values of FGF 23 compared with patients with eGFR > 60 ml/min per 1.73 m(2). The Gensini score values significantly correlated with gender; arterial hypertension; and HDL cholesterol, eGFR, iPTH, FGF 23, and fetuin A levels. After the adjustments for traditional and uremia-related cardiovascular risk factors, the FGF 23 and fetuin A remained significant predictors of the Gensini score. CONCLUSIONS: This study suggests that in a relatively young population with mild-to-moderate alteration of kidney function and with less traditional cardiovascular risk factors, anomalies of the serum FGF 23 and fetuin A levels appear early in the course of disease and are independent major predictors for extent of CAD.