Characteristics and perioperative variables between patients who stopped or continued to use opioids 6 weeks following total knee arthroplasty
| Not using opioid at 6 weeks | Using opioid at 6 weeks | P value | |
| Sample size, n (%) | 290 (82.6) | 61 (17.4) | |
| Sociodemographic characteristics | |||
| Mean age (SD) in years | 68.4 (8.2) | 67.5 (7.9) | 0.46 |
| Sex, n (%) | 0.96 | ||
| Female | 175 (60.4) | 37 (60.7) | |
| Male | 115 (39.7) | 24 (39.3) | |
| Race, n (%) | 0.86 | ||
| White | 275 (94.8) | 60 (98.4) | |
| Black | 3 (1.0) | 0 (0.0) | |
| Other | 12 (4.2) | 1 (1.6) | |
| Comorbidities | |||
| ASA classification, n (%) | 0.03* | ||
| 1 or 2 | 181 (62.4) | 29 (47.5) | |
| 3 or 4 | 109 (37.6) | 32 (52.5) | |
| Active antidepressant prescription, n (%) | 60 (20.7) | 19 (31.2) | 0.08 |
| Active benzodiazepine prescription, n (%) | 40 (13.8) | 12 (19.7) | 0.24 |
| History of alcohol abuse, n (%) | 4 (1.4) | 6 (9.8) | <0.01* |
| Active tobacco or marijuana use, n (%) | 15 (5.2) | 7 (11.5) | 0.72 |
| Hospital course | |||
| Median length of stay (IQR) in days | 3 (2 to 3) | 3 (2 to 3) | 0.10 |
| Disposition, n (%) | 0.86 | ||
| Home | 245 (84.5) | 51 (83.6) | |
| Rehabilitation facility | 45 (15.5) | 10 (16.4) | |
| Top quartile for average hourly inpatient opioid consumption, n (%) | 66 (22.8) | 20 (32.8) | 0.10 |
| Top quartile for discharge prescription size, n (%) | 67 (23.1 | 16 (26.2) | 0.60 |
*Indicates statistical significance (p<0.05).
ASA, American Society of Anesthesiologists.