Univariate associations between antenatal factors and the risk of chronic lung disease
| Respiratory pattern | |||||
|---|---|---|---|---|---|
| Antenatal factors | Low FiO2 | PD | EPPD | Row N | |
| Gestational age (weeks) | 23–24 | 30 | 76 | 85 | 250 |
| 25–26 | 19 | 57 | 64 | 560 | |
| 27 | 15 | 33 | 62 | 394 | |
| Birth weight (g) | ≤750 | 41 | 74 | 81 | 461 |
| 751–1000 | 14 | 43 | 58 | 512 | |
| >1000 | 11 | 29 | 51 | 231 | |
| Birth weight z score | <−2 | 70 | 68 | 86 | 75 |
| ≥−2 to −1 | 38 | 70 | 80 | 163 | |
| ≥−1 | 13 | 47 | 65 | 966 | |
| Sex | Male | 18 | 56 | 69 | 638 |
| Female | 16 | 47 | 69 | 566 | |
| Antenatal steroids | Complete | 17 | 50 | 71 | 767 |
| Partial | 16 | 56 | 67 | 316 | |
| None | 21 | 53 | 64 | 117 | |
| Number of fetuses | Single | 18 | 53 | 69 | 819 |
| Multiple | 16 | 50 | 69 | 385 | |
| Caesarean delivery | Yes | 16 | 54 | 70 | 804 |
| No | 24 | 48 | 68 | 400 | |
| Delivery indication | PTL | 15 | 49 | 67 | 526 |
| pPROM | 12 | 52 | 67 | 265 | |
| Preeclampsia | 40 | 64 | 74 | 163 | |
| Abruption | 19 | 48 | 73 | 126 | |
| Cervical insufficiency | 13 | 45 | 57 | 72 | |
| Fetal indication | 10 | 67 | 85 | 52 | |
| Per cent CLD | 17 | 52 | 69 | 52 | |
| Maximum column N | 240 | 456 | 508 | 1204 | |
The right-most column gives the maximum number of infants with the attribute listed in each row; any differences are due to missing data. All other data are the percentage of infants with CLD among those infants with the attribute listed in the two left columns and the respiratory patterns listed as column headings. For example, among infants with a gestational age of 23–24 weeks who had the Low FiO2 respiratory pattern, the prevalence of CLD was 30%.
CLD, chronic lung disease; EPPD, early and persistent lung dysfunction; FiO2, fraction of inspired oxygen; PD, pulmonary deterioration; pPROM, prolonged, premature rupture of membranes; PTL, preterm labour.