Table 2. Clinical characteristics.
| Characteristics | Group 1 (n = 1288) | Group 2 (n = 673) | p-value |
|---|---|---|---|
| Probiotics | |||
| Probiotic treatment | 0 (0) | 626 (93) | NA |
| duration (days) | NA | 11 (4–30) | NA |
| NEC and sepsis | |||
| NEC ≥ stage 2 | 101 (8) | 34 (5) | 0.02 |
| Surgical NEC | 58 (5) | 19 (3) | 0.07 |
| Age at diagnosis of NEC (days) | 12 (7–19) | 11 (6–23) | 0.59 |
| NEC after transfer | 25 (2) | 10 (2) | 0.59 |
| NEC related mortality | 35 (3) | 15 (2) | 0.52 |
| Any abdominal surgery | 104 (8) | 54 (8) | 0.97 |
| Suspected late onset sepsis | 569 (44) | 270 (40) | 0.09 |
| Blood culture-proven sepsis | 264 (21) | 126 (19) | 0.35 |
| Any IV antibiotic treatment | 1218 (95) | 624 (93) | 0.10 |
| Respiratory support | |||
| Surfactant | 610 (47) | 345 (51) | 0.10 |
| Endotracheal mechanical ventilation | 781 (61) | 353 (53) | <0.001 |
| duration of ventilation (days) | 2 (0–8) | 1 (0–6) | <0.01 |
| CPAP or non-invasive ventilation | 1084 (84) | 579 (86) | 0.27 |
| Nutrition and growth | |||
| Parenteral nutrition | 1271 (99) | 664 (99) | 0.97 |
| Reached full enteral feeding at NICU | 646 (50) | 257 (38) | <0.001 |
| at day | 12 (9–18) | 13 (9–20) | 0.14 |
| Maximum weight loss (% of birth weight) | 8 (3–11) | 8 (4–11) | 0.05 |
| at day | 3 (2–4) | 3 (2–4) | 0.20 |
| Birth weight regained at NICU | 737 (57) | 378 (56) | 0.66 |
| at day | 8 (6–11) | 8 (5–10) | 0.21 |
| Other | |||
| Length of NICU stay (days) | 10 (4–26) | 9 (4–25) | 0.64 |
| Umbilical artery catheter placed | 384 (30) | 137 (28) | 0.46 |
| Inotropic treatment | 298 (23) | 166 (25) | 0.45 |
| Red blood cell transfusion | 586 (46) | 206 (31) | <0.001 |
| PDA treatment, medical surgical | 305 (24) | 143 (21) | 0.22 |
| 95 (7) | 55 (8) | 0.53 | |
| Intraventricular haemorrhage | 196 (15) | 82 (12) | 0.07 |
Shown are numbers (%) for categorical variables and medians (interquartile range) for continuous variables for patients born before (group 1) and after (group 2) introduction of routine probiotic treatment, and p-values.
Data on NEC mortality were collected until day 120 (including time after NICU discharge), all other data shown relate to the NICU admission with a maximum of 120 days. NEC related mortality based on death certificates and medical records. Full enteral feeding was defined as an enteral milk intake of 150 ml*kg-1*day-1. No data were missing.
Abbreviations: CI, confidence interval; CPAP, continuous positive airway pressure; IV, intravenous; NA, not applicable; NEC, necrotising enterocolitis; NICU, neonatal intensive care unit; PDA, patent ductus arteriosus.