Table 1. Baseline Characteristics of Patients.
| Characteristic | Patients, No. (%) (N = 698) | |
|---|---|---|
| Single-dose antibiotics (n = 345) | Multiple-dose antibiotics (n = 353) | |
| Participating site | ||
| Department of Reconstructive Plastic Surgery, Karolinska University Hospital | 141 (40.9) | 137 (38.8) |
| Department of Breast Surgery, Karolinska University Hospital | 81 (23.5) | 87 (24.6) |
| South General Hospital Stockholm | 51 (14.8) | 61 (17.3) |
| Capio St Göran’s Hospital | 35 (10.1) | 32 (9.0) |
| Danderyd Hospital | 12 (3.5) | 12 (3.4) |
| Halland Hospital, Halmstad | 14 (4.0) | 13 (3.7) |
| Uppsala University Hospital | 9 (2.6) | 9 (2.5) |
| Umeå University Hospital | 2 (0.6) | 2 (0.6) |
| Age at surgery, median (range), y | 46 (25-76) | 47 (19-78) |
| Body mass index, median (range)a | 23 (17-38) | 23 (17-38) |
| <20 | 38 (11.0) | 33 (9.8) |
| 20-26 | 202 (58.6) | 209 (59.2) |
| 25-30 | 89 (25.8) | 92 (26.1) |
| >30 | 16 (4.6) | 19 (5.4) |
| Missing | 0 | 0 |
| Nicotine use (current smoker or moist powder tobacco user) | ||
| No | 323 (93.6) | 336 (95.2) |
| Yes | 22 (6.4) | 17 (4.8) |
| Missing | 0 | 0 |
| Diabetes type 1 or 2 | ||
| No | 341 (98.8) | 349 (98.9) |
| Yes | 4 (1.2) | 4 (1.1) |
| Missing | 0 | 0 |
| Radiation therapy (previous or adjuvant) | ||
| No | 222 (64.3) | 225 (63.7) |
| Yes | 123 (35.7) | 128 (36.3) |
| Missing | 0 | 0 |
| Indication for mastectomy | ||
| Therapeutic | 207 (60.0) | 220 (62.3) |
| Risk-reducing | 113 (32.8) | 109 (30.9) |
| Both therapeutic and risk-reducing | 25 (7.2) | 24 (6.8) |
| Missing | 0 | 0 |
| Type of reconstruction | ||
| Therapeutic mastectomy (immediate or delayed reconstruction) | 207 (60.0) | 220 (62.3) |
| Immediate reconstruction | 161 (46.6) | 170 (48.1) |
| Delayed reconstruction (previous therapeutic mastectomy) | 46 (13.3) | 50 (14.2) |
| Bilateral RRM, no cancer diagnosis | 113 (32.8) | 109 (30.9) |
| Immediate reconstruction | 113 (32.8) | 109 (30.9) |
| Delayed reconstruction | 0 | 0 |
| Therapeutic and contralateral RRM | 25 (7.2) | 24 (6.8) |
| Therapeutic and contralateral RRM bilateral immediate reconstruction | 14 (4.1) | 16 (4.5) |
| Delayed reconstruction following previous therapeutic, and contralateral RRM with immediate reconstruction | 11 (3.2) | 8 (2.3) |
| Missing | 0 | 0 |
| Bilateral reconstruction | ||
| No | 217 (62.9) | 224 (63.5) |
| Yes | 128 (37.1) | 129 (36.5) |
| Missing | 0 | 0 |
| Axillary surgery | ||
| None | 190 (55.1) | 193 (54.8) |
| Yes | 155 (44.9) | 159 (45.2) |
| Sentinel lymph node biopsy | 110 (31.9) | 102 (29.0) |
| Axillary lymph node dissection | 45 (13.0) | 57 (16.2) |
| Missing | 0 | 1 (0.3) |
| Type of implant | ||
| Permanent implant | 110 (32.1) | 112 (31.7) |
| Tissue expander | 230 (67.1) | 239 (67.7) |
| Permanent and tissue expander (bilateral case) | 3 (0.9) | 2 (0.6) |
| Missing | 2 (0.6) | 0 |
| Chemotherapy | ||
| None | 239 (69.4) | 235 (66.6) |
| Neoadjuvant | 33 (9.6) | 41 (11.6) |
| Adjuvant | 59 (17.1) | 64 (18.1) |
| Neoadjuvant and adjuvant | 14 (4.1) | 13 (3.7) |
| Missing | 2 (0.6) | 0 |
| Type of antibiotic prophylaxis | ||
| Cloxacillin | 321 (93.0) | 322 (91.2) |
| Clindamycin | 22 (6.4) | 31 (8.8) |
| Different antibiotic than study drugs | 1 (0.3) | 0 |
| Missing | 1 (0.3) | 0 |
| Adverse events | ||
| No | 308 (89.3) | 295 (83.6) |
| Yes | 37 (10.7) | 58 (16.4) |
| Missing | 0 | 0 |
Abbreviation: RRM, risk-reducing mastectomy.
a
Body mass index is calculated as weight in kilograms divided by height in meters squared.