Table 2. Demographics and outcomes by BMI category (normal weight, overweight, obese/superobese).
| Normal weight | Overweight | Obese | p-value | p-value (normal weight vs obese) | |
|---|---|---|---|---|---|
| N=160 (42%) | N=120 (32%) | N=97 (26%) | |||
| Age (years) | 34 (24-51) | 33 (26-47) | 33 (24-45) | 0.6642 | 0.3493 |
| Male gender | 78% | 85% | 84% | 0.2380 | 0.2660 |
| BMI (kg/m2) | 22.5 (20.9-23.8) | 27.1 (25.9-28.3) | 33.0 (31.3-36.1) | 0.0001 | 0.0001 |
| Blunt injury rate | 72% | 51% | 55% | 0.0010 | 0.0070 |
| ISS | 18 +/- 15 | 18 +/- 15 | 17 +/- 15 | 0.6313 | 0.3022 |
| ED arrival GCS | 13 (7-15) | 14 (8-15) | 14 (7-15) | 0.1480 | 0.1514 |
| AIS-head | 2 (0-4.5) | 0 (0-3.5) | 0 (0-3) | 0.0129 | 0.0083 |
| Prehospital crystalloid (mL) | 50 (0-250) | 100 (0-250) | 100 (0-250) | 0.4915 | 0.4282 |
| ED admit temperature (°) | 36.1 +/- 0.9 | 36.2 +/- 0.9 | 36.3 +/- 1.0 | 0.6560 | 0.3774 |
| Admit pH | 7.31 +/- 0.12 | 7.31 +/- 0.11 | 7.29 +/- 0.15 | 0.3640 | 0.2349 |
| Admit base excess | -2.4 +/- 5.5 | -3.2 +/- 4.6 | -3.7 +/- 6.5 | 0.2872 | 0.1494 |
| Admit INR | 1.1 (1.1-1.2) | 1.1 (1-1.2) | 1.1 (1-1.2) | 0.3063 | 0.2687 |
| Admit PTT (s) | 28 (26-32) | 28 (26-31) | 28 (26-30) | 0.4731 | 0.2448 |
| Admit platelet count (× 109/L) | 269+/- 83 | 283 +/- 80 | 303 +/- 101 | 0.0105 | 0.0038 |
| Admit fibrinogen (mg/dL) | 230 +/- 94 | 210 +/- 100 | 243 +/- 95 | 0.2050 | 0.4233 |
| Admit Factor II (% activity) | 76 +/- 18 | 72 +/- 25 | 77 +/- 23 | 0.4983 | 0.8298 |
| Admit Factor V (% activity) | 39 (23-58) | 41 (19-53) | 41 (28-61) | 0.3127 | 0.4349 |
| Admit Factor VII (% activity) | 82 (63-107) | 79 (55-100) | 77 (62-111) | 0.4481 | 0.6201 |
| Admit Factor VIII (% activity) | 156 (89-268) | 176 (108-298) | 147 (74-263) | 0.5145 | 0.7304 |
| Admit Factor IX (% activity) | 119 +/- 39 | 118 +/- 46 | 134 +/- 48 | 0.0942 | 0.0416 |
| Admit Factor × (% activity) | 78 +/- 18 | 75 +/- 26 | 81 +/- 24 | 0.3473 | 0.3694 |
| Admit ATIII (% activity) | 79 +/- 26 | 68 +/- 24 | 72 +/- 30 | 0.0711 | 0.3573 |
| Admit protein C (% activity) | 79 +/- 27 | 84 +/- 26 | 84 +/- 31 | 0.5522 | 0.1289 |
| Admit D-dimer (ug/mL) | 4.00 (1.13-7.70) | 2.67 (0.44-6.29) | 1.88 (0.45-4.00) | 0.0128 | 0.0039 |
| Admit CK R-time (min) | 4.4 +/- 1.4 | 4.6 +/- 1.5 | 4.7 +/- 1.3 | 0.2835 | 0.1036 |
| Admit CK K-time (min) | 1.3 (1.2-1.6) | 1.4 (1.2-1.8) | 1.3 (1.2-1.7) | 0.8687 | 0.8955 |
| Admit CK alpha angle (°) | 69.3 +/- 6.4 | 69.2 +/- 5.9 | 69.4 +/- 6.1 | 0.7850 | 0.8857 |
| Admit CK MA (mm) | 63.4 +/- 6.1 | 64.5 +/- 5.0 | 65.7 +/- 6.1 | 0.0374 | 0.0157 |
| Admit CK LY30 (%) | 1.0 (0.1-2.5) | 0.9 (0.1-2.8) | 0.6 (0.1-2.7) | 0.9524 | 0.9456 |
| Admit FLEV (mg/dL) | 351 +/- 84 | 358 +/- 70 | 407 +/- 105 | 0.0670 | 0.0077 |
| pRBC 0-24 hours (units) | 0 (0-2.5) | 0 (0-3.5) | 0 (0-2) | 0.6480 | 0.7743 |
| FFP 0-24 hours (units) | 0 (0-1) | 0 (0-2) | 0 (0-1) | 0.1300 | 0.9672 |
| PLTS 0-24 hours (units) | 0 (0-0) | 0 (0-0) | 0 (0-0) | 0.6655 | 0.5200 |
| MT in 24 hours | 12% | 18% | 5% | 0.2870 | 0.5270 |
| Total hospital days | 7 (3-15) | 7 (2-20) | 6 (3-18) | 0.7482 | 0.4431 |
| Ventilator free days | 26 (21-28) | 27 (19-28) | 27 (20-28) | 0.8412 | 0.6154 |
| VAP rate | 0% | 2% | 0% | 0.1620 | n/d |
| ARDS rate | 12% | 12% | 8% | 0.7330 | 0.2880 |
| MOF rate | 9% | 8% | 9% | 0.9730 | 1.0000 |
| Mortality rate at 6 hours | 1% | 1% | 0% | 0.7900 | 0.5280 |
| Mortality rate at 24 hours | 2% | 3% | 3% | 0.7160 | 0.6760 |
| Mortality rate at discharge | 15% | 9% | 10% | 0.3080 | 0.3440 |
| TE complication rate | 4% | 4% | 9% | 0.2410 | 0.1810 |
Comparisons of the normal weight, overweight, and obese groups. Data are mean +/- SD, median (inter-quartile range), or n (%) as indicated. Data for skewed variables reported as median with inter-quartile ranges. p-value bolded if <0.0167 as corrected for multiple comparisons. BMI=body mass index. ED=emergency department. GCS=Glascow Coma Scale. ISS=injury severity score. AIS=abbreviated injury score. INR=international normalized ratio. PTT=partial thromboplastic time. ATIII=antithrombin III. CK=citrated kaolin. R-time=reaction time. MA=maximum amplitude. LY30=lysis at 30 min. FLEV=functional fibrinogen level. pRBC=packed red blood cell units. FFP=fresh frozen plasma units. PLTS=platelet units. MT=massive transfusion. Ventilator free days, counted for the first 28 days of hospitalization. Patients who expired received 0 ventilator free days. VAP=ventilator associated pneumonia. ARDS=acute respiratory distress syndrome by Berlin criteria. MOF=multiple organ failure. TE=thromboembolic