When the researchers followed those patients for a median of 29 months, NAPCR was significantly associated with an annual decline in eGFR and remained statistically associated in the multivariate regression analysis, even after adjusting for UACR, baseline eGFR, and cystatin C. In the subgroup analysis, the predictive power of NAPCR to DKD progression remained statistically significant in patients with normo-albuminuria or eGFR ≥ 60 mL/min/1.73 m2, suggesting that NAPCR had prognostic values for early stage DKD. This evidence concerns the gene CST3 and diabetic kidney disease.