Demographic and preoperative risk factor variables of patients with and without surgical site infection
| Variable | Group; no. (%) of patients* | p value | |
|---|---|---|---|
| No SSI n = 282 | SSI n = 55 | ||
| Age, yr, median (IQR) | 40 (31–52) | 54 (43–61) | < 0.001† |
| Sex | |||
| Male | 104 (36.9) | 40 (73) | < 0.001‡ |
| Female | 178 (63.1) | 15 (27) | |
| Body mass index, median (IQR) | 29 (25–36) | 27 (25–31) | 0.02† |
| ASA score | < 0.001‡ | ||
| 1 | 143 (50.7) | 16 (29) | |
| 2 | 107 (37.9) | 13 (24) | |
| 3 | 31 (11.0) | 18 (33) | |
| 4 | 1 (0.4) | 6 (11) | |
| 5 | 0 (0.0) | 2 (4) | |
| Diabetic | 52 (18.4) | 18 (33) | 0.02‡ |
| Smoking status | 0.004‡ | ||
| Smoker | 36 (12.8) | 5 (9) | |
| Former smoker | 8 (2.8) | 5 (9) | |
| Nonsmoker | 216 (76.6) | 34 (62) | |
| Unknown | 22 (7.8) | 11 (20) | |
| Steroid use | 11 (3.9) | 4 (7) | 0.3‡ |
| Chemotherapy | 6 (2.1) | 4 (7) | 0.04‡ |
| Preoperative hemoglobin level, g/L, median (IQR) | 13 (12–14) | 12 (11–14) | 0.1† |
| Preoperative albumin level, g/L, median (IQR) | 36 (33–38) | 31 (26–35) | < 0.001† |
| Benign disease | 267 (94.7) | 33 (60) | < 0.001‡ |