In the multivariate Cox model, after adjusting for age, sex, diabetes duration, diabetic retinopathy, serum albumin, proteinuria, eGFR, and ACEI/ARB treatment, the HRs for classes IIb, III, and IV (IIa as the reference) and glomerular C3 deposition were 3.29 (95% CI, 0.99–10.98; p = 0.05), 3.96 (95% CI, 1.23–12.79; p = 0.021), 5.37 (95% CI, 1.52–18.90; p = 0.009), and 1.82 (95% CI, 1.23–2.68; p = 0.002), respectively (Table 4). This evidence concerns the gene C3 and diabetes mellitus.