CST3 and diabetes mellitus: At baseline, the mean diabetes duration was 18.4 ± 8.80 years, glycated hemoglobin (Hgb) was 7.0 ± 1.05, and eGFR was 40.3 ± 9.35 ml/min per 1.73 m2 using the 2012 CKD-EPI cystatin C and sCr formulas.