Logistic models showed that increasing FCP was a risk factor for DKD (OR 1.350, 95% CI 1.189-1.532; P < 0.05), and increasing C2/C0 was a protective factor for both DKD (OR 0.894, 95% CI 0.833-0.959; P < 0.05) and DR (OR 0.851, 95% CI 0.787-0.919; P < 0.05), even after adjusting for all potential confounders (age, sex, SBP, HbA1c, TC, TG, LDL, HDL, smoking history, education, duration of diabetes, ever insulin use, and BMI). Here, INS is linked to diabetic kidney disease.