Table 1.
Patient demographics
| Demographic data | Unadjusted cohort comparison | Matched cohort comparison | ||||
|---|---|---|---|---|---|---|
| OA | FNF | p value | OA | FNF | p value | |
| Number | 41,739 | 953 | – | 953 | 953 | – |
| Age (years) | 65 | 73.4 | < 0.001* | 73 | 73 | 0.748 |
| Female | 55% | 68.3% | < 0.001* | 70% | 68% | 0.428 |
| Medical comorbidities | ||||||
| ASA | ||||||
| 1 | 4% | 3% | 0.041* | 3% | 3% | 0.782 |
| 2 | 56% | 32% | < 0.001* | 32% | 32% | 0.883 |
| 3 | 39% | 54% | < 0.001* | 54% | 54% | 0.890 |
| 4 | 2% | 11% | < 0.001* | 11% | 11% | 0.885 |
| Number of comorbidities | 1 | 2 | < 0.001* | 2 | 2 | 0.332 |
| Obesity BMI 30–34.9 kg/m2 | 25% | 11% | < 0.001* | 11% | 11% | 0.885 |
| Obesity BMI 35–39.9 kg/m2 | 12% | 3% | < 0.001* | 3% | 3% | 1.000 |
| Obesity BMI ≥ 40 kg/m2 | 8% | 7% | 0.580 | 6% | 7% | 0.166 |
| CHF | 0% | 2% | < 0.001* | 3% | 2% | 0.452 |
| Myocardial infarction | 0% | 1% | < 0.001* | 0% | 1% | 0.483 |
| Cardiac surgery | 1% | 2% | 0.003 | 2% | 2% | 0.248 |
| PCI | 2% | 2% | 0.081 | 2% | 2% | 0.328 |
| Angina | 0% | 0% | 0.961 | 0% | 0% | 0.571 |
| COPD | 4% | 9% | < 0.001* | 8% | 9% | 0.743 |
| Renal failure | 0% | 0% | 0.416 | 0% | 0% | 0.571 |
| Alcohol use | 1% | 1% | 0.564 | 1% | 1% | 0.796 |
| PVD | 0% | 0% | 0.263 | 0% | 0% | 0.214 |
| Dialysis | 0% | 1% | < 0.001 | 1% | 1% | 0.834 |
| Stroke—with deficit | 0% | 1% | < 0.001* | 1% | 1% | 0.512 |
| Stroke—no deficit | 0% | 2% | < 0.001* | 2% | 2% | 0.871 |
| Metastatic cancer | 0% | 1% | < 0.001* | 1% | 1% | 0.277 |
| Steroid use | 3% | 8% | < 0.001* | 6% | 8% | 0.155 |
| Weight loss | 0% | 1% | < 0.001* | 0% | 1% | 0.176 |
| Bleeding disorder | 3% | 14% | < 0.001* | 15% | 4% | 0.435 |
| Recent operation | 0% | 0% | 0.079 | 0% | 0% | 0.571 |
| Hypertension | 58% | 59% | 0.412 | 59% | 59% | 1.000 |
| TIA | 1% | 4% | < 0.001* | 4% | 4% | 0.727 |
| Smoking | 13% | 15% | 0.272 | 15% | 15% | 0.652 |
| Diabetes | 11% | 15% | < 0.001* | 14% | 15% | 0.362 |
| Race | ||||||
| White | 81% | 84% | 0.007* | 83% | 84% | 0.577 |
| Black | 6% | 5% | 0.063 | 6% | 5% | 0.470 |
| Asian | 1% | 2% | 0.145 | 2% | 2% | 0.737 |
| Other | 12% | 9% | 0.013* | 9% | 9% | 0.752 |
| Preoperative laboratory values | ||||||
| Creatinine (mg/dL) | 0.9 | 1.0 | 0.004* | 1.0 | 1.0 | 0.576 |
| Albumin (g/dL) | 4.1 | 3.6 | < 0.001* | 4.0 | 3.6 | <0.001* |
| WBC count (109 cells/L) | 7 | 10 | < 0.001* | 7 | 10 | <0.001* |
| Hematocrit (%) | 41 | 37 | < 0.001* | 39 | 37 | <0.001* |
| Platelets (109/L) | 248 | 215 | < 0.001* | 243 | 215 | < 0.001* |
| INR | 1.0 | 1.1 | < 0.001* | 1.1 | 1.1 | 0.022 |
| BUN (mg/dL) | 18 | 19 | 0.001* | 20 | 19 | 0.076 |
| Time to OR (days) | 0 | 2 | < 0.001* | 0 | 2 | < 0.001* |
| Intraoperative data | ||||||
| Anesthesia | ||||||
| General | 61% | 78% | < 0.001* | 62% | 78% | < 0.001* |
| Spinal | 39% | 22% | < 0.001* | 38% | 22% | < 0.001* |
| Operative time (minutes) | 95 | 98 | 0.018* | 92 | 98 | 0.015* |
* Probability values < 0.05; OA = osteoarthritis; FNF = femoral neck fracture; ASA = American Society of Anesthesiologists physical status; BMI = body mass index; CHF = congestive heart failure; PCI = percutaneous coronary intervention; COPD = chronic obstructive pulmonary disease; PVD = peripheral vascular disease; TIA = transient ischemic attack; WBC = white blood cell; INR = international normalized ratio; BUN = blood urea nitrogen; OR = operating room.