Univariate associations with delirium
| Covariate, % (n) | Delirium (n=28) | No delirium* (n=489) | P value |
| Age, mean (SE) | 77.7 (1.5) | 75.7 (0.4) | 0.19 |
| Female sex | 67.9% (19) | 65.2% (318) | 0.77 |
| White race | 85.7% (24) | 93.7% (458) | 0.11 |
| ISS >9 (other minor injury) | 32.1% (9) | 29.1% (142) | 0.73 |
| Fall cause of injury | 100% (28) | 95.1% (466) | 0.63 |
| ASA score ≥III | 85.7% (24) | 66.3% (324) | 0.03 |
| Any comorbidity† | 96.4% (27) | 80.2% (392) | 0.03 |
| Hypertension | 67.9% (19) | 56.4% (276) | 0.24 |
| Diabetes | 25.0% (7) | 16.8% (82) | 0.30 |
| Dependent | 28.6% (8) | 17.2% (84) | 0.13 |
| COPD | 21.4% (6) | 13.3% (65) | 0.25 |
| Smoker | 25.0% (7) | 9.8% (48) | 0.02 |
| Anticoagulant | 17.9% (5) | 18.8% (92) | 0.90 |
| Advanced directive | 21.4% (6) | 11.4% (56) | 0.13 |
| Fracture type‡ | 0.70 | ||
| Head or neck | 57.1% (16) | 55.3% (268) | |
| Intertrochanteric | 42.9% (12) | 42.3% (205) | |
| Subtrochanteric | 0% | 2.5% (12) | |
| Surgical information | |||
| Hip replacement (vs repair) | 50.0% (14) | 38.7% (189) | 0.23 |
| General anesthesia | 82.1% (23) | 86.7% (424) | 0.57 |
| Delayed surgery >24 hours | 35.7% (10) | 20.9% (102) | 0.06 |
| Hours to surgery, median (IQR) | 20.4 (18–27) | 18.1 (10–23) | 0.006 |
| Outcomes: median (IQR) OME and mean (SE) pain NRS score | |||
| Preoperative OME | 40.5 (19–78) | 30.0 (12–59) | 0.16 |
| Postoperative OME | 40.9 (12–89) | 40.0 (15–92) | 0.96 |
| Preoperative pain | 3.6 (0.54) | 4.1 (0.12) | 0.35 |
| Postoperative pain | 2.6 (0.55) | 3.1 (0.11) | 0.38 |
bold values denote statistical significance p<0.05.
*Delirium from arrival through 48 hours postoperatively. No delirium group included seven patients with delirium >48 hours postoperatively.
†Individual comorbidities tabulated if they occurred in at least 10% of patients.
‡Four patients with ‘other’ or ‘unspecified’; these are later coded as not head/neck.
ASA, American Society of Anesthesiologist; COPD, chronic obstructive pulmonary disease; ISS, injury severity score; NRS, numeric rating scale; OME, oral morphine equivalents.