Demographic characteristics of the study participants
| Characteristic | Control group (n = 97) |
Hydromorphone group (n = 96) | |
|---|---|---|---|
| Age (yr) | 66.6 ± 14.9 | 67.2 ± 9.6 | 0.501 |
| Sex | |||
| Male | 51 (52.6) | 46 (47.9) | 0.421 |
| Female | 46 (47.4) | 50 (52.1) | 0.413 |
| Localization | |||
| Head | 11 (11.3) | 13 (13.6) | 0.235 |
| Cervial | 15 (15.5) | 17 (17.7) | 0.322 |
| Thoracic | 45 (46.4) | 39 (40.6) | 0.438 |
| Lumbar | 26 (26.8) | 27 (28.1) | 0.193 |
| Duration of pain (mo) | 6.4 ± 14.8 | 5.0 ± 19.6 | 0.362 |
| Initial NRS | 6.5 ± 1.6 | 6.9 ± 1.5 | 0.471 |
Values are presented as mean ± standard deviation or number (%).
NRS: numerical rating scale.