Table 2.
The quality and performance of the PLS-DA model fitted to the complete data are summarized for comparing five study groups pairwise
| Group | Reference | Profile | N (S) | N (M) | N (C) | R2X | R2Y | Q2 | Se | Sp | AUROC | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Metabolomic deviation of a patient group from non-ARDS ventilated ICU control | |||||||||||||
| H1N1/A | CTL | Complete | 50 | 131 | 2 | 0.30 | 0.84 | 0.70 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 46 | 3 | 0.49 | 0.92 | 0.78 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 2 | 2 | 1.00 | 0.80 | 0.78 | 1.00 | 1.00 | 1.00 | ||||
| PNA/A | CTL | Complete | 50 | 131 | 2 | 0.27 | 0.77 | 0.63 | 1.00 | 0.96 | 0.99 | ||
| Signature | 50 | 43 | 3 | 0.46 | 0.79 | 0.71 | 0.96 | 0.96 | 0.99 | ||||
| Biomarkers | 50 | 8 | 1 | 0.66 | 0.53 | 0.51 | 0.88 | 1.00 | 0.97 | ||||
| C19/A | CTL | Complete | 50 | 131 | 2 | 0.22 | 0.96 | 0.85 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 47 | 2 | 0.41 | 0.95 | 0.92 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 4 | 1 | 0.71 | 0.82 | 0.81 | 1.00 | 1.00 | 1.00 | ||||
| Metabolomic difference of ARDS patient groups | |||||||||||||
| PNA/A | H1N1/A | Complete | 50 | 131 | 4 | 0.43 | 0.98 | 0.77 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 41 | 3 | 0.53 | 0.95 | 0.87 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 3 | 2 | 0.97 | 0.66 | 0.62 | 0.92 | 0.92 | 0.98 | ||||
| C19/A | H1N1/A | Complete | 50 | 131 | 3 | 0.40 | 0.90 | 0.74 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 45 | 3 | 0.54 | 0.90 | 0.79 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 7 | 1 | 0.61 | 0.67 | 0.66 | 1.00 | 1.00 | 1.00 | ||||
| C19/A | PNA/A | Complete | 50 | 131 | 2 | 0.33 | 0.92 | 0.82 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 41 | 2 | 0.50 | 0.94 | 0.90 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 11 | 2 | 0.76 | 0.89 | 0.87 | 1.00 | 1.00 | 1.00 | ||||
| Metabolomic comparison between ARDS ICU and non-ICU patients | |||||||||||||
| C19/A | C19/P | Complete | 50 | 131 | 3 | 0.35 | 0.86 | 0.62 | 1.00 | 1.00 | 1.00 | ||
| Signature | 50 | 36 | 3 | 0.47 | 0.83 | 0.66 | 1.00 | 1.00 | 1.00 | ||||
| Biomarkers | 50 | 1 | 1 | 1.00 | 0.30 | 0.28 | 0.72 | 0.72 | 0.81 | ||||
Three different profiles are displayed: (1) Complete = profile consisting of all metabolites, (2) Signature = profile consisting of metabolites in which the score of variable importance on projection is greater than 1, and (3) Biomarkers = metabolites found by our selection method over 1,000 bootstrap samples with favorable metric to highlight differences between cohorts
CTL: non-ARDS ventilated control patients admitted to ICU, H1N1/A = H1N1-induced ARDS patients admitted to ICU, PNA/A = bacterial pneumonia-induced ARDS patients admitted to ICU, C19/A = SARS-CoV-2-induced ARDS patients admitted to ICU, C19/P = SARS-CoV-2 patients admitted to hospital but not sick enough to be admitted to ICU
N(S) = number of samples, N(M) = number of metabolites, N(C) = number of components