CST4 and diabetic kidney disease: Multivariate logistic regression model analysis results concluded that postprandial glucose/C-peptide, insulin resistance index, serum cystatin, and uric acid were independent risk factors for the risk of disease progression in patients with diabetic nephropathy, indicating that postprandial glucose/C-peptide, insulin resistance index, serum cystatin C, and uric acid can affect the risk of disease progression in patients with diabetic nephropathy to a certain extent.