Fibroblast Growth Factor-23 and Carotid Artery Intima Media Thickness in Chronic Kidney Disease

BACKGROUND The cause of early-accelerated atherosclerosis development observed in Chronic Kidney Disease (CKD) is not fully understood. The determination of the relationship between the levels of fibroblast growth factor 23 (FGF-23) and the development of endothelial dysfunction, left ventricular hypertrophy, and myocardial infarction lends support to the possibility that FGF-23 plays a role in the development of atherosclerosis in CKD. Only a few studies, however, have been conducted that analyze the relationship between FGF-23 levels in the progression of CKD and the development of atherosclerosis, and these studies have generally been limited to those patients receiving dialysis therapy due to end stage renal disease (ESRD). METHODS In the present study, carotid artery intima-media thicknesses (IMT) were measured ultrasonically as a marker of atherosclerosis in 91 patients with CKD stage 3 - 4 (61 female and 30 male, age between 19 - 65 years, glomerular filtration rate [GFR] 15 - 60 mL/min 1.73 m2, CKD was not related to diabetes mellitus, and without cardiovascular-cerebral disease) in contrast to 36 healthy volunteers (26 female and 10 male, age between 19 - 65 years, GFR > 90 mL/min 1.73 m2, and without any diagnoses of acute or chronic disease), and a possible role of FGF-23 on atherosclerosis was analyzed. RESULTS Patients were similar to controls with respect to age, gender, smoking status, body mass index, and plasma glucose and lipid profile. On the other hand, IMT measurements (p < 0.00001) and FGF-23 levels (p = 0.00012) were significantly higher in patients than controls. IMT was measured above the subclinical atherosclerosis limit of 0.750 mm in 54% of the patients. Multivariate regression analysis showed that patients' age, high sensitive c-reactive protein (hsCRP), and FGF-23 levels were independent predictors of IMT (p < 0.00001, r = 0.559). Independent of other variables, every 1 μmol/L increase in FGF-23 levels resulted in 0.444 mm increase of IMT measurements in patients with CKD. CONCLUSIONS Our findings suggest that monitoring serum FGF-23 may be useful as a non-invasive indicator of subclinical atherosclerosis in patients with chronic kidney disease.