Table 4.
Cox Model of BDNF Gene Risk Score (GRS)
| Variable | Parameter Estimate |
Standard Error |
Chi- Square |
p value |
Hazard Ratio |
95% Hazard Ratio CI# |
|---|---|---|---|---|---|---|
| A. BDNF GRS predicting time until death, 0–7d post-injury (n=279, 33 events) | ||||||
| Age | 0.02419 | 0.01118 | 4.681 | 0.031 | 1.024 | (1.002 – 1.047) |
| GCS* | −0.35982 | 0.08939 | 16.204 | <0.001 | 0.698 | (0.586–0.831) |
| NBS¥ | 0.47135 | 0.23476 | 4.031 | 0.045 | 1.602 | (1.011–2.538) |
| Pulmonary Complication |
−2.16656 | 0.43392 | 24.930 | <0.001 | 0.115 | (0.049–0.268) |
| Cardiac Complication |
1.69773 | 0.59712 | 8.083 | 0.005 | 5.462 | (1.695–17.603) |
| GRS (1 risk SNP)** | −1.04771 | 0.41069 | 6.508 | 0.011 | 0.351 | (0.157–0.784) |
| GRS (2 risk SNP)** | −1.05395 | 0.48134 | 4.794 | 0.029 | 0.349 | (0.136–0.895) |
| B. BDNF GRS predicting time until death, 8–-365d post-injury (n=246, 39 events) | ||||||
|---|---|---|---|---|---|---|
| Age | 0.07065 | 0.01109 | 40.594 | <0.001 | 1.073 | (1.050–1.097) |
| GCS* | −0.30681 | 0.07779 | 15.556 | <0.001 | 0.736 | (0.632–0.857) |
| Acute PTS | 0.74307 | 0.59263 | 1.572 | 0.210 | 2.102 | (0.658–6.717) |
| Intracranial Hemorrhage |
−0.74676 | 0.36615 | 4.160 | 0.041 | 0.474 | (0.231–0.971) |
| Wound Complication |
0.95654 | 0.46986 | 4.144 | 0.042 | 2.603 | (1.036–6.537) |
| GRS 1** | 0.38055 | 0.48137 | 0.625 | 0.429 | 1.463 | (0.570–3.758) |
| GRS 2** | 0.28517 | 0.52061 | 0.300 | 0.584 | 1.330 | (0.479–3.690) |
| C. BDNF GRS x Age interaction predicting time until death, 8–365d post-injury (n=246, with 39 events) | ||||||
|---|---|---|---|---|---|---|
| Age | 0.15128 | 0.02536 | 35.5716 | <.0001 | 1.163 | (1.107–1.223) |
| GCS* | 0.29814 | 0.07504 | 15.7837 | <.0001 | 0.742 | (0.641–0.860) |
| Acute PTS | 1.44824 | 0.61090 | 5.6202 | 0.0178 | 4.256 | (1.285–14.092) |
| Intracranial Hemorrhage |
−0.59617 | 0.36387 | 2.6845 | 0.1013 | 0.551 | (0.270–1.124) |
| Wound Complication |
1.10612 | 0.47471 | 5.4293 | 0.0198 | 3.023 | (1.192–7.664) |
| GRS 1** | 3.42870 | 1.07292 | 10.2123 | 0.0014 | 30.836 | (3.765–252.542) |
| GRS 2** | 6.25552 | 1.77560 | 12.4119 | 0.0004 | 520.881 | (16.05–16909.54) |
| GRS x Age Interaction |
−0.06964 | 0.01912 | 13.2643 | 0.0003 | 0.933 | (0.898–0.968) |
*
GCS (Glasgow Coma Scale, Best in 24 hours)
¥
Neurological Burden Score
**
GRS (0 risk SNP) was the reference category
#
CI: Confidence Interval