Table 2.
Associations between Plasma Markers of Endothelial Activation and Blood-Brain Barrier Injury and Delirium
| Percentile | Adjusted Differencea | |||
|---|---|---|---|---|
| Biomarker | 25th | 75th | Estimate (95% CI) | P Value |
| Associations with delirium/coma-free days among all patients (N=134) | ||||
| PAI-1(ng/mL) | 74.3 | 171.5 | −1.72 (−2.65, −0.79)b | 0.002 |
| E-selectin(ng/mL) | 9.8 | 29.8 | 0.24 (−0.62, 1.10)b | 0.02 |
| Ang-2(pg/mL) | 9639 | 26369 | −0.25 (−1.32, 0.82) | 0.64 |
| S100B(pg/mL) | 38.4 | 128.7 | −1.70 (−2.66, −0.74) | <0.001 |
| RHI | 1.21 | 1.76 | 1.09 (0.50, 1.68) | <0.001 |
| Associations with delirium days among survivors (N=113) | ||||
| PAI-1(ng/mL) | 74.3 | 171.5 | 0.83 (0.25, 1.40)b | 0.007 |
| E-selectin(ng/mL) | 9.8 | 29.8 | 0.28 (−0.26, 0.83)b | 0.12 |
| Ang-2(pg/mL) | 9639 | 26369 | 0.22 (−0.54, 0.99) | 0.57 |
| S100B(pg/mL) | 38.4 | 128.7 | 0.93 (0.23, 1.63) | 0.01 |
| RHI | 1.21 | 1.76 | −0.63 (−1.15, −0.12) | 0.02 |
Results, which were determined using multiple linear regression, show the adjusted difference (and 95% confidence intervals) in delirium/coma-free days or delirium days when the specified biomarker of endothelial activation or blood-brain barrier injury increased from the 25th percentile value to the 75th percentile value. In the delirium/coma-free days models, a negative adjusted difference indicates that higher biomarker concentrations were associated with worse cognitive outcomes, i.e., fewer days without delirium or coma. Alternatively, in the delirium duration model, a positive adjusted difference indicates that higher biomarker concentrations were associated with worse cognitive outcomes, i.e., more days of delirium. Adjusted differences, however, may vary depending on comparators in nonlinear associations and are best represented graphically (Figure 1 and 2).
Indicates the association was nonlinear.
Abbreviations: Ang-2, angiopoietin-2; PAI-1, plasminogen activator inhibitor-1; RHI, reactive hyperemia index