Table 3: Multiple stepwise regression and principal component regression of Ln(ACR) and related factors.

Standard errorStandard regression coefficient

Principal Component 1.0380.0520.59220.031<0.001

Since the values of HIF-1α, VEGF, vWF, and IGF-1 were correlated, their unique principal component was substituted for them in the model and the principal component = 0.803 HIF-1α + 0.864 VEGF + 0.929 IGF-1 + 0.725 vWf (HIF-1α: hypoxia-inducible factor-1α; VEGF: vascular endothelial growth factor; IGF-1: insulin-like growth factor-1; vWf: von Willebrand factor). In the formula, each variable was no longer the original variable but standardized variable and the coefficients before the standardized variables represented the correlation coefficients of principal component and the corresponding original variables. Since only one principal component was extracted among the four serum factors and the correlation coefficients were all close to 1, it showed that the four factors were highly correlated and the component could almost contain all the information of the four variables.
UA: uric acid; BUN: blood urea nitrogen; eGFR: estimated glomerular filtration rate; TG: triglyceride; 25(OH)VD3: 25-hydroxy vitamin D3; LDL: low-density lipoprotein.