GDF15 and chronic kidney disease: The addition of GDF-15 to model 0 improved C-statistics for predicting 1-, 2-, and 3-year risk of CKD progression at borderline significance (95% CI: −0.001 to 0.02, 95% CI: −0.001 to 0.01 and 95% CI: −0.001 to 0.01 at 1, 2, and 3 years respectively) (Table 3).