Table 2 Clinical and demographic characteristics of preterm infants with or without BPD*P < 0.05
|  | BPD I group 345 (56.2) | BPD II group 174 (28.3) | BPD III group 89 (14.5) | Non-BPD group 672 (52.3) | Z/χ2 | P value |
|---|---|---|---|---|---|---|
GA, weeks, median (IQR) | 29 (27,30) | 28 (27,29) | 28 (27,29.3) | 29 (28.0,30.0) | 87.324 | < 0.001* |
BW, grams, median (IQR) | 1185 (950,1463) | 1070 (908,1293) | 1045 (888,1243) | 1340 (1100,1530) | 112.246 | < 0.001* |
Male sex, n (%) | 205 (59.4) | 96 (55.2) | 54 (60.7) | 383 (57.1) | 1.302 | 0.729 |
Apgar score at 5 min, score, n (%) | 43.417 | < 0.001* | ||||
<7 | 56 (16.2) | 35 (20.1) | 31 (34.8) | 69 (10.3) | Â | Â |
≥7 | 289 (83.8) | 139 (79.9) | 58 (65.2) | 603 (89.7) |  |  |
Maternal diabetes, N (%) | 67 (19.4) | 38 (21.8) | 17 (19.1) | 139 (20.7) | 0.552 | 0.907 |
Maternal hypertension, N (%) | 90 (26.1) | 44 (25.3) | 16 (18.0) | 144 (21.4) | 4.579 | 0.205 |
Assisted reproduction, N (%) | 65 (19.0) | 56 (32.2) | 23 (25.8) | 150 (22.4) | 11.915 | 0.008* |
PROM > 18 h,N (%) | 87 (25.2) | 35 (20.1) | 17 (19.1) | 183 (27.2) | 5.621 | 0.132 |
IUGR, N (%) | 25 (7.2) | 15 (8.6) | 11 (12.4) | 47 (7.0) | 3.512 | 0.319 |
Respiratory distress score at admission, score |  |  |  |  | 59.890 | < 0.001* |
5–8, N (%) | 311 (90.1) | 150 (86.2) | 72 (80.9) | 658 (97.8) |  |  |
> 8, N (%) | 34 (9.9) | 24 (13.8) | 17 (19.1) | 15 (2.2) |  |  |
Surfactant, N (%) | 272 (78.8) | 160 (92) | 83 (93.3) | 414 (61.6) | 99.386 | < 0.001* |
Mechanical ventilation, N (%) | 201 (58.3) | 139 (79.9) | 76 (85.4) | 281 (41.8) | 125.018 | < 0.001* |
Ventilator days, ds, median (IQR) | 6.0 (3.0,13.4) | 9.6 (4.0,22.0) | 21.3 (8.0,38.1) | 3.0 (1.2,7.3) | 241.258 | < 0.001* |
hsPDA, N (%) | 106 (30.7) | 59 (33.9) | 38 (42.7) | 115 (17.1) | 50.748 | < 0.001* |
NEC(Stage ≥ 2), N (%) | 38 (11.0) | 33 (19.0) | 20 (22.5) | 41 (6.1) | 41.383 | < 0.001* |
LOS, ds, median (IQR) | 56 (44,73) | 68 (54,86) | 78 (60,106) | 46 (35,59) | 295.460 | < 0.001* |