Table 2.
Plasma Glial Fibrillary Acidic Protein Autoantibody Levels in Patients with Traumatic Brain Injury*
| Acute TBI | Chronic TBI | |||||
|---|---|---|---|---|---|---|
| Post-injury time | N = 196 | N = 21 | ||||
| Mean ± SD | 10.6 ± 6.3 (h) | 176.4 ± 44.5 (days) | ||||
| Range | 0.5 to 23.9 (h) | 16.0 to 250.0 (days) | ||||
| GCS | N | Mean (SE) | Sig. (p) | N | Mean (SE) | Sig. (p) |
| 3–8 | 12 | 3.35 (0.87) | 0.136 | — | — | — |
| 9–12 | 6 | 4.37 (1.59) | — | — | ||
| 13–15 | 120 | 6.16 (0.72) | — | — | ||
| Unknown | 18 | 1.73 (2.35) | — | — | ||
| Previous TBI | N | Mean (SE) | Sig. (p) | N | Mean (SE) | Sig. (p) |
| None | 106 | 2.97 (0.37) [a] | <0.001 | 4 | 13.25 (2.43) | 0.956 |
| Yes, without LOC | 47 | 8.01 (1.80) [b] | 4 | 15.41 (6.56) | ||
| Yes, with LOC | 43 | 9.11 (1.42) [b] | 13 | 15.54 (4.18) | ||
| Admission head CT | N | Mean (SE) | Sig. (p) | N | Mean (SE) | Sig. (p) |
| Negative | 108 | 6.48 (0.87) | 0.197 | — | — | 0.168 |
| Extra-axial only | 22 | 5.02 (2.01) | 5 | 14.32 (6.01) | ||
| Intra-axial only | 24 | 5.72 (2.04) | 3 | 8.27 (2.88) | ||
| Extra- + intra-axial | 42 | 3.22 (0.49) | 3 | 13.82 (7.98) | ||
| Unknown | — | — | 10 | 13.07 (3.86) |
TBI, traumatic brain injury; SD, standard deviation; GCS, Glasgow Coma Scale; SE, standard error of the mean; LOC, loss of consciousness; CT, computed tomography;.
*
Blood draw for GFAP-AutoAb post-injury time calculated from time of injury. GCS data were unavailable for patients with chronic TBI. CT pathology was positive for all patients with chronic TBI with CT data. [a] and [b] denote statistically significant subgroups on the Tukey post hoc test.