Table 1.
Characteristics of the total population and comparison between infants with moderate–severe BPD and infants with mild or no moderate–severe BPD.
| Total Population n = 4341 | Moderate–Severe BPD n = 1897/4341 (43.7%) | No Moderate–Severe BPD n = 2444/4341 (56.3%) | p | OR (95% CI) | |
|---|---|---|---|---|---|
| Gestational age (weeks) | 25.7 (0.84) | 25.5 (0.900) | 25.8 (0.85) | <0.001 | |
| Birth weight (g) | 812.58 (151.004) | 773.69 (145.975) | 842.77 (148.007) | <0.001 | |
| Male sex | 2262/4341 (52.1) | 1072/1897 (56.5) | 1190 /2444 (48.7)) | <0.001 | 1.369 (1.214–1.545) |
| Multiple birth | 1188/4341 (27.4) | 548/1897 (28.9) | 640/2444 (26.2) | 0.048 | 1.145 (1.001–1.309) |
| IVF | 793/4046 (19.6) | 357/1783 (20.0) | 436/2263 (19.3) | 0.548 | 1.049 (0.897–1.226) |
| Antenatal steroids | 3889/4341 (89.6) | 1694/1897 (89.3) | 2195 /2444 (89.8) | 0.583 | 0.947 (0.778–1.151) |
| Complete antenatal steroids | 2846/4341 (65.6) | 1242/1897 (65.5) | 1604/2444 (65.6) | 0.877 | |
| Outborn | 195/4341 (4.5) | 95/1897 (5) | 100/2444 (4.1) | 0.148 | 1.232 (0.967–1.647) |
| Caesarean section | 2343/4341 (54) | 1043/1897 (55) | 1300 /2444 (53.2) | 0.241 | 1.075 (0.953–1.212) |
| Chorioamnionitis | 1215/3078 (39.5) | 562/1397 (40.3) | 653/1681 (38.8) | 0.437 | 1.032 (0.954–1.117) |
| Maternal hypertensive disorder | 279/3085 (9) | 136/1394 (9.8) | 143/1691 (8.5) | 0.21 | 1.170 (0.915–1.497) |
| 1 min Apgar score | 5 (4–7) a | 5 (4–7) b | 6 (4–7) c | <0.001 | |
| 5 min Apgar score | 8 (7–9) d | 8 (6–8) e | 8 (7–9) f | <0.001 | |
| CRIB score | 4 (2–7) g | 5 (4–8) h | 4 (2–6) i | <0.001 | |
| iMV | 3746/4341 (86.3) | 1753/1897 (92.4) | 1993/2444 (81.5) | <0.001 | 2.755 (2.259–3.359) |
| HFOV | 1209/4321 (28) | 856/1888 (45.3) | 353/2433 (14.5) | <0.001 | 4.887 (4.229–5.6489 |
| Duration of iMV (hours) | 440.73 (554.78) | 699.02 (677.1) | 242.42 (318.42) | <0.001 | |
| nCPAP | 3863/4333 (89.2) | 1670/1893 (88.2) | 2194/2440 (89.9) | 0.074 | 0.840 (0.693–1.017) |
| nIPPV | 2002/3473 (57.6)) | 922/1521 (60.6) | 1080/1953 (55.3) | 0.002 | 1.244 (1.086–1.426) |
| iNO | 317/4136 (7.7%) | 253/1803 (14) | 64/2333 (2.7) | <0.001 | 5.787 (4.366–7.670) |
| Surfactant therapy | 3440/4333 (79.4) | 1624/1896 (85.7) | 1816/2437 (74.5) | <0.001 | 2.042 (1.744–2.390) |
| Prophylactic indomethacin | 286/4335 (6.6) | 74/1983 (3.9) | 212/2442 (8.7) | <0.001 | 0.428 (0.326–0.562) |
| Postnatal systemic steroids | 1177/4324 (27.2) | 851/1892 (45.0) | 326/2432 (13.4) | <0.001 | 5.281 (4.556–6.122) |
| Early onset sepsis | 295/4326 (6.8) | 121/1887 (6.4) | 174/2439 (7.1) | 0.35 | 0.892 (0.701–1.134) |
| Late onset sepsis | 2773/4339 (63) | 1405/1896 (74.1) | 1328/2443 (54.4) | <0.001 | 2.403 (2.110–2.736) |
| Inotropic therapy | 1808/4139 (43.7) | 1016/1808 (56.3) | 792/2334(33.9) | <0.001 | 2.507 (2.209–2.845) |
| NEC | 513/4341 (11.8) | 277/1897 (14.6) | 236/2444 (9.7) | <0.001 | 1.600 (1.329–1.925) |
| NEC surgery | 379/4335 (8.7) | 209/1895 (11) | 170/2440 (7) | <0.001 | 1.655 (1.339–2.046) |
| PDA medical/surgical treatment | 2576/4268 (60.35) | 1336/1869 (71.5) | 1240/2399 (51.7) | <0.001 | 2.343 (2.060–2.664) |
| Major cerebral lesion | 872/4341 (20.1) | 483/1897 (25.5) | 389/2444 (15.9) | <0.001 | 1.805 (1.554–2.096) |
| ROP surgery | 674/4341 (15.5) | 405/1897 (21.3) | 269/2444 (11) | <0.001 | 2.195 (1.856–2.595) |
| ROP grade 3 or more | 685/4244 (16.1) | 428/1856 (23.1) | 257/2388 (10.8) | <0.001 | 2.485 (2.100–2.942) |
| Duration of admission in NICU (days) | 99 (30) j | 114 (32) k | 87 (22) l | <0.001 | |
| Exclusive HM feeding at discharge | 1493/4222 (35.2) | 559/1851 (30.2) | 934/2391 (39.1) | <0.001 | 0.675 (0.593–0.768) |
| Any amount of HM feeding at discharge | 2474/4242 (58.3) | 953/1851 (58.3) | 1521/2391 (63.6) | <0.001 | 0.607 (0.537–0.698) |
Qualitative variables expressed by n (%) and p value was calculated via chi-square test. Quantitative variables expressed by mean (SD) and p value was calculated using t-test. Ordinal variables (scores) expressed by median (range) and p value was calculated using Mann–Whitney test. col %, column percent. a. Data obtained in 4286/4341; b. data obtained in 1873/1897; c. data obtained in 2413/2444; d. data obtained in 4214/4341; e. data obtained in 1837/1897; f. data obtained in 2377/2444; g. data obtained in 3766/4341; h. data obtained in 1637/1897; i. data obtained in 2129/2444; j. data obtained in 4314/4341; k. data obtained in 1884/1897; l. data obtained in 2430/2444. Abbreviations. IVF: in vitro fertilization, CRIB: clinical index risk for babies; HFOV: high-frequency oscillatory ventilation, nCPAP: nasal continuous positive pressure, nIPPV: nasal intermittent positive pressure, INO: inhaled nitric oxide, NEC: necrotizing enterocolitis, PDA: patent ductus arteriosus, ROP: retinopathy of prematurity, NICU: neonatal intensive care unit, HM: human milk.