Association of Circulating FGF-23 and Klotho with Cardiovascular Disease in Patients with Chronic Kidney Disease

Abs tractAim: Chronic kidney disease (CKD) contributes to an increased risk of cardiovascular disease (CVD) beyond traditional risk factors, partly through the fibroblast growth factor 23 (FGF-23) and Klotho pathways.This study examined the association between circulating FGF-23 and Klotho levels and CVD in individuals with CKD.Methods: This cross-sectional study included 110 patients with CKD treated at University of Health Sciences Türkiye, Istanbul Haseki Training and Research Hospital.Patients were classified into CVD-positive (n=56) and CVD-negative (n=54) groups according to the presence of CVD, defined as coronary artery disease, ischaemic stroke, or peripheral arterial disease.Serum FGF-23 and Klotho levels were quantified using enzyme-linked immunosorbent assay, and routine biochemical and hormonal parameters were simultaneously assessed.Statistical analyses included group comparisons, correlation analyses, and binary logistic regression.Results: Patients with CVD had higher serum FGF-23 levels than those without CVD (p=0.022),whereas Klotho levels did not differ between the groups.Multivariate regression analyses showed that FGF-23 was associated with CVD [odds ratio =1.0026 (1.0002-1.0049),p=0.032] after adjusting for estimated glomerular filtration rate, age, sex, diabetes mellitus, and hypertension.Klotho showed inverse correlations with creatinine (r=-0.297,p=0.029) in CVD-negative patients and with glucose (r=-0.299,p=0.025) in CVD-positive patients and was positively associated with FGF-23 (r=0.558,p<0.001) in CVD-positive patients.Conclusion: Elevated FGF-23 levels were associated with CVD in patients with CKD, whereas Klotho levels did not distinguish patients with CVD.These findings suggest a possible relationship between FGF-23 and CVD in CKD; however, further studies are required.