One-Time FGF23 Level Predicts Cardiovascular Risk in CKD

A single measurement of fibroblast growth factor-23 (FGF23) predicts the risk of cardiovascular events in patients with chronic kidney disease (CKD), reports Nephrology Dialysis Transplantation.

The study included 439 adults with CKD whose median estimated GFR was 36 mL/min per 1.73 m2, drawn from a larger randomized trial. All had paired samples for measurement of FGF23 over 2 years. Changes in FGF23 and time-averaged FGF23 were compared with one-time values as predictors of clinical events.

Both one-time and time-averaged FGF23 were positively associated with a primary composite outcome of myocardial infarction, stroke, and cardiovascular mortality. There were also significant associations for overall mortality, start of renal replacement therapy, and congestive heart failure.

One-time and time-averaged FGF23 had similar predictive value: adjusted hazard ratio 1.71 and 1.91 for the composite outcome, respectively. Change in FGF23 over time was associated only with the start of renal replacement therapy. The median FGF23 value increased from 109 to 149 U/mL over 2 years.

Fibroblast growth factor-23 increases with progression of CKD and is an independent predictor of adverse clinical events. This prospective study confirms that FGF23 is a cardiovascular risk factor in CKD, and it shows that two measurements do not improve the predictive value over a one-time FGF23 value. The authors note that their study included relatively short follow-up times and did not specifically target FGF23 levels [Bouma-de Krijger A, et al. Time-averaged level of fibroblast growth factor-23 and clinical events in chronic kidney disease. Nephrol Dial Transplant 2014; 29:88–97].

March 2014 (Vol. 6, Number 3)