Table 5.
Subject Characteristics by Respiratory Diagnosis Status
| No Respiratory Diagnosis (n = 152) | Respiratory Diagnosis (n = 372) | P Value | |
|---|---|---|---|
| Birth weight, g | 970.5 (815 to 1,092.5) | 910 (756 to 1,085) | 0.14 |
| Birth weight z-score | −0.399 (−1.04 to 0.24) | −0.215 (−0.76 to 0.29) | 0.06 |
| Birth weight strata, g | |||
| 500–749 | 29 (19.1%) | 87 (23.4%) | 0.28 |
| 750–999 | 57 (37.5%) | 140 (37.6%) | 0.98 |
| 1,000–1,250 | 66 (43.4%) | 145 (39.0%) | 0.35 |
| Small for gestational age | 52 (34.2%) | 89 (23.9%) | 0.02 |
| Birth length, cm | 35.45 (33 to 37) | 35 (32 to 37) | 0.03 |
| Birth head circumference, cm | 25 (23.5 to 26.5) | 24.5 (23 to 26) | <0.01 |
| Gestational age, wk | 27 (26 to 29) | 27 (25 to 28) | <0.01 |
| Maternal age, yr | 29 (25 to 33) | 28 (22 to 32) | 0.01 |
| Male sex | 71 (46.7%) | 192 (51.6%) | 0.31 |
| Maternal race | |||
| Asian | 3 (2.0%) | 4 (1.1%) | 0.42 |
| Black or African American | 18 (11.8%) | 92 (24.7%) | <0.01 |
| Hawaiian or Pacific Islander | 0 (0%) | 0 (0%) | — |
| White | 130 (85.5%) | 273 (73.4%) | <0.01 |
| Other | 0 (0%) | 1 (0.3%) | — |
| Unknown | 1 (0.7%) | 2 (0.5%) | 0.868 |
| Maternal ethnicity | |||
| Hispanic or Latino | 30 (19.7%) | 69 (18.5%) | 0.75 |
| Not Hispanic or Latino | 122 (80.3%) | 302 (81.2%) | 0.81 |
| Multiple gestations | 37 (24.3%) | 98 (26.3%) | 0.63 |
| Antenatal corticosteroids | 124 (81.6%) | 312 (83.9%) | 0.75 |
| Cesarean section delivery | 104 (68.4%) | 262 (70.4%) | 0.65 |
| Intubated in delivery room | 85 (55.9%) | 239 (64.2%) | 0.06 |
| Intubated in NICU | 34 (22.4%) | 76 (20.4%) | 0.87 |
| Surfactant in delivery room | 103 (67.8%) | 308 (82.8%) | <0.01 |
| PDA medical treatment | 62 (40.8%) | 149 (40.1%) | 0.92 |
| PDA surgical ligation | 16 (10.5%) | 48 (12.9%) | 0.23 |
| IVH grade 3 or 4 | 6 (3.9%) | 15 (4.0%) | 0.96 |
| Threshold ROP | 4 (2.6%) | 37 (9.9%) | 0.01 |
| BPD severity | |||
| None or mild | 105 (69.1%) | 205 (55.1%) | <0.01 |
| Moderate or severe | 47 (30.9%) | 167 (44.9%) | <0.01 |
| Oxygen use at discharge, yes (%) | 90 (59.2%) | 209 (56.2%) | 0.53 |
Definition of abbreviations: BPD = bronchopulmonary dysplasia; IVH = intraventricular hemorrhage; NICU = neonatal intensive care unit; PDA = patent ductus arteriosus; ROP = retinopathy of prematurity.
Descriptive statistics [count (percent) or median (interquartile range)] and univariate comparisons for the study demographics, stratified by respiratory diagnosis over the first 2 years of life.