Table 3: Multivariable analysis of risk factors for removal of an uninflamed appendix in patients who had appendectomy for suspected acute appendicitis.
| No. (col%) N = 1140 | No. (row%) uninflamed appendix | Unadjusted odds ratio | p-value | Adjusted odds ratio | p-value | |
|---|---|---|---|---|---|---|
| Gender | ||||||
| Male | 604 (53.0) | 58 (9.6) | 1 | 1 | ||
| Female | 536 (47.0) | 78 (14.6) | 1.60 (1.12 to 2.30) | 0.011 | 1.58 (1.06 to 2.35) | 0.025 |
| Age | ||||||
| < 15 years | 208 (18.2) | 27 (13.0) | 1 | 1 | ||
| 15-39 years | 605 (53.1) | 77 (12.7) | 0.98 (0.61 to 1.56) | 0.93 | 1.35 (0.78 to 2.32) | 0.28 |
| 40+ years | 327 (28.7) | 8 (9.8) | 0.73 (0.42 to 1.25) | 0.25 | 0.94 (0.51 to 1.75) | 0.86 |
| Temperature | ||||||
| < 37.8 ℃ | 599 (52.5) | 70 (11.7) | 1 | 1 | ||
| 37.8-38.4 ℃ | 323 (28.3) | 40 (12.4) | 1.07 (0.71 to 1.62) | 0.76 | 1.08 (0.68 to 1.71) | 0.74 |
| 38.5+ ℃ | 218 (19.1) | 26 (11.9) | 1.02 (0.63 to 1.65) | 0.93 | 1.06 (0.60 to 1.86) | 0.84 |
| Leucocyte count | ||||||
| < 10.0*109/l | 208 (18.2) | 56 (26.9) | 1 | 1 | ||
| 10.0-14.9*109/l | 495 (43.4) | 49 (9.9) | 0.30 (0.20 to 0.46) | < 0.001 | 0.26 (0.16 to 0.41) | < 0.001 |
| 15.0+ *109/l | 437 (38.3) | 31 (7.1) | 0.21 (0.13 to 0.33) | < 0.001 | 0.16 (0.09 to 0.26) | < 0.001 |
| C-reactive protein | ||||||
| < 20 | 377 (33.1) | 56 (14.9) | 1 | 0.073 | 1 | |
| 20-39 | 193 (16.9) | 14 (7.3) | 0.45 (0.24 to 0.83) | 0.01 | 0.36 (0.18 to 0.70) | 0.002 |
| 40-99 | 332 (29.1) | 38 (11.4) | 0.74 (0.48 to 1.15) | 0.18 | 0.70 (0.43 to 1.14) | 0.15 |
| 100+ | 238 (20.9) | 28 (11.8) | 0.76 (0.47 to 1.24) | 0.76 | 0.77 (0.44 to 1.35) | 0.36 |
| Ultrasound and/or CT examination | ||||||
| Not performed | 667 (58.5) | 82 (12.3) | 1 | 1 | ||
| Direct signs of appendicitis | 375 (32.9) | 22 (5.9) | 0.45 (0.27 to 0.73) | 0.001 | 0.46 (0.27 to 0.79) | 0.004 |
| Indirect signs of appendicitis | 26 (2.3) | 8 (30.8) | 3.17 (1.34 to 7.53) | 0.009 | 3.53 (1.38 to 9.04) | 0.008 |
| Inconclusive examination | 72 (6.3) | 24 (33.3) | 3.57 (2.08 to 6.13) | < 0.001 | 3.87 (2.11 to 9.10) | < 0.001 |
| Type of operation | ||||||
| Laparoscopy* | 291 (25.5) | 24 (8.2) | 1 | 1 | ||
| Open | 849 (74.5) | 112 (13.2) | 1.69 (1.07 to 2.69) | 0.026 | 2.06 (1.20 to 3.53) | 0.009 |