Fig. 2
Metabolomic and lipidomic profiles and multivariate diagnostic model. A A PLS-DA model constructed from metabolomic and lipidomic profiling separated seropositive RA and seronegative RA patients from controls (NCs). B Volcano plot of metabolomic and lipidomic levels of RA versus NCs (x axis, fold change of RA to NCs; y axis, adjusted p value). Metabolites or lipids with VIPplsda > 1, fold change > 1.2, adjusted p-value < 0.05 are colored in red and those with VIPplsda > 1, fold change < 0.8, adjusted p-value < 0.05 in blue. C Metabolic pathway enrichment analysis of RA. D Metabolites and lipids with VIPplsda > 2 selected for building a multivariate classification model. E ROC analysis of the multivariate classification model