Fig. 2

Differences in serum metabolome profiles between type 2 diabetic patients with and without the incidence of 1-year MACEs after PCI in the discovery and internal validation sets. A and B The OPLS-DA scatter plot. Each dot and square represents the serum metabolomic profile of a single participant in a 2-dimensional space. The ellipses represent 95% confidence intervals. Cross-validation plot with 200 permutations in the discovery (C) and internal validation sets (D). The volcano plot of differential metabolites in the discovery (E) and internal validation sets (F). The vertical dashed lines indicate the threshold of fold changes > 4/3 or < 3/4. The horizontal dashed line indicates the threshold of FDR < 0.05. G The pathway enrichment analysis of all differential metabolites. The horizontal dashed line indicates the threshold of FDR < 0.05. H The Venn diagram. MACEs major adverse cardiovascular events; FDR false discovery rate; FC fold change; VIP variable importance in the projection