CST3 and Insulin resistance: Multivariate logistic regression analysis demonstrated that postprandial glucose/C-peptide (OR = 0.747; P=0.004), insulin resistance index (OR = 0.072; P=0.012), serum cystatin C (OR = 0.023; P=0.020), and uric acid (OR = 0.967; P=0.039) were independent risk factors for the risk of disease progression in diabetic nephropathy patients.