Short-term effects of sevelamer-carbonate on fibroblast growth factor 23 and pulse wave velocity in patients with normophosphataemic chronic kidney disease Stage 3.

backgroundHigh concentrations of both phosphate and fibroblast growth factor 23 (FGF23) observed in chronic kidney disease (CKD) are associated with an increased risk of cardiovascular morbidity and mortality. Pulse wave velocity (PWV) is a surrogate marker for cardiovascular events and all-cause mortality. It is not known whether a reduction of FGF23 or phosphate alters cardiovascular risk. Sevelamer has shown to have the ability to reduce both phosphate and FGF23 concentrations. Furthermore, reduction of PWV is reported with sevelamer use as well, but it is unclear if this is mediated by decline of phosphate or FGF23. We investigated if sevelamer induced a decline in PWV and if this was associated with a reduction in FGF23.

methodsIn all, 24 normophosphataemic CKD Stage 3 patients started treatment with a fixed dose of sevelamer-carbonate (Renvela

resultsA total of 18 patients completed 8 weeks of treatment with sevelamer and were analysed. Overall, treatment with sevelamer did not induce a significant reduction of PWV (β = -0.36, P = 0.12). However, in patients with less vascular calcification (lower KI score), there was a statistically significant reduction of PWV, adjusted for mean arterial pressure, after treatment (β = 0.63, P = 0.02). Addition of FGF23 to the model did not alter this association. Mediation analysis yielded similar results. FGF23 did not decrease during treatment with sevelamer.

conclusionIn this short-term pilot study in normophosphataemic CKD patients, treatment with sevelamer did not improve PWV. In subgroup analysis, however, PWV improved in patients with no or limited abdominal aorta calcifications. This was not associated with a decline of FGF23.