#1514 Elevated FGF23 increases systolic, and diastolic blood pressure, and pulse pressure in non-dialysis CKD patients

Abstract

Abstract Background and Aims Arterial stiffness is associated with high blood pressure. Elevated fibroblast growth factor 23 (FGF23) has been shown to produce changes in the phenotype of vascular smooth muscle cells that may cause an increase in arterial stiffness and an impairment of vascular function. Thus, we aimed to evaluate whether, in g5 non-dialysis CKD patients, higher concentration FGF23 is associated with elevated systolic (SBP), diastolic blood pressure (DBP), and pulse pressure (PP). Method We included 159 g5 non-dialysis CKD patients. Generalized additive models analyzed the association between intact FGF23, SBP, DBP, and PP. The body composition measurement was used to evaluate overhydration (OH). Given the potential non-linear relationship between iFGF23, with the other variables, iFGF23 was categorized into tertiles (T1 ≤ 389 pg/ml, T2 = 389—517 pg/ml, and T3 = >517 pg/ml). Results The mean age was 65.2 ± 14.7 years. 46% (n = 73) were female. The mean values of SBP and DBP were 158.8 ± 21.3 mmHg, and 87.2 ± 12.3 mmHg respectively, and the PP was 76.6 ± 20 mmHg. The median concentration of iFGF23 was 468.3 (268.8—904.9) pg/ml. It was observed a positive correlation between iFGF23 tertiles and SBP (p < 0.001), DBP (<0.01), PP (p = 0.02), and OH (p < 0.01) (Fig. 1). Multivariate generalized additive models showed an independent association of iFGF23 with SBP (Beta 5.16, CI 34-68), DBP (Beta 38.7, CI 24-53), and PP (Beta 36.3, CI 22.2-50.4). This association was not influenced by OH (%). Residual diuresis did not attenuate the association of iFGF23 with SBP, DBP, and PP. Conclusion Elevated FGF23 was associated with higher SBP, DBP, and PP in g5 non-dialysis CKD patients. This association was not modified by OH and residual diuresis.