Table 2.
Outcomes and Other Neonatal Morbidities in Survivors Only
| Variable | Combined Population | Primary Favorable Outcome | Primary Unfavorable Outcome |
|---|---|---|---|
| Favorable primary outcome | |||
| Only on respiratory medications at discharge <40 wk PMA, % (n/N) | 1.5% (11/717) | 0% (0/385) | 3.3% (11/332) |
| Only on respiratory support at discharge <40 wk PMA, % (n/N) | 0.7% (5/717) | 0% (0/385) | 1.5% (5/332) |
| On respiratory medications and respiratory support at discharge <40 wk PMA, % (n/N) | 0.8% (6/717) | 0% (0/385) | 1.8% (6/332) |
| Only on respiratory medications as inpatient at 40 wk PMA, % (n/N) | 3.1% (22/717) | 0% (0/385) | 6.6% (22/332) |
| Only on respiratory support as inpatient at 40 wk PMA, % (n/N) | 11.6% (83/717) | 0% (0/385) | 25.0% (83/332) |
| On respiratory medications and respiratory support as inpatient at 40 wk PMA, % (n/N) | 19.2% (138/717) | 0% (0/385) | 41.6% (138/332) |
| Death ⩽40 wk PMA, % (n/N) | 9.3% (67/717) | 0% (0/385) | 20.2% (67/332) |
| Discharged alive on no respiratory medications or respiratory support <40 wk PMA, % (n/N) | 33.5% (240/717) | 62.3% (240/385) | 0% (0/332) |
| Alive on no respiratory medications or respiratory support as inpatient at 40 wk PMA, % (n/N) | 20.2% (145/717) | 37.7% (145/385) | 0% (0/332) |
| Secondary outcomes | |||
| Moderate BPD (NICHD definition, % (n/N) Need for any oxygen at 36 wk PMA or discharge, whichever comes first; 36 wk survivors only |
44% (288/654) | 17.4% (67/385) | 82.2% (221/269) |
| Severe BPD (NICHD definition), % (n/N) Need for ⩾30% oxygen and/or positive pressure (PPV or NCPAP) at 36 wk PMA or discharge, whichever comes first; infants alive at 36 wk PMA |
31.2% (204/654) | 7.0% (27/385) | 65.8% (177/269) |
| Severe BPD, % (n/N) On invasive mechanical ventilation at 36 wk PMA; infants alive at 36 wk PMA |
9.9% (65/654) | 0.5% (2/385) | 23.4% (63/269) |
| Highly unfavorable outcome: death or IMV at 40 wk PMA, % (n/N) | 15.8% (113/717) | 0% (0/385) | 34.0% (113/332) |
| Moderately unfavorable outcome: noninvasive positive pressure at 40 wk PMA, % (n/N) | 6.0% (43/717) | 0% (0/385) | 13.0% (43/332) |
| Mildly unfavorable outcome: nasal cannula or only medications at 40 wk PMA or discharged home on medications or oxygen before 40 wk, % (n/N) | 24.5% (176/717) | 0% (0/385) | 53.0% (176/332) |
| Duration of respiratory support (IMV or CPAP or O2), d, mean ± SD; median, 25th–75th, n through discharge, up to 40 wk (infants alive at 40 wk PMA) | 57.79 ± 33.21; 59, 28.25–88; n = 651 | 38.88 ± 25.53; 36; 16–58; n = 385 | 85.16 ± 22.12; 90; 75–101; n = 266 |
| Duration of mechanical ventilation, d, mean ± SD; median, 25th–75th, n through discharge, up to 40 wk; 40 wk survivors only | 21.57 ± 28.01; 7; 1–35.75, n = 651 | 7.94 ± 13.2; 2; 0–9.25; n = 385 | 41.28 ± 31.83; 38; 10–65; n = 266 |
| Pulmonary hypertension diagnosis >34 wk (echocardiography proven), % (n/N) through discharge up to 40 wk; 40 wk survivors only | 9.4% (61/650) | 0.5% (2/385) | 22.3% (59/265) |
| Other morbidity in 40 wk survivors | |||
| Any intraventricular hemorrhage (grades 1–4) through exit or 36 wk PMA, % (n/N) | 30.3% (197/651) | 22.9% (88/385) | 41% (109/266) |
| Severe intraventricular hemorrhage (grade 3 or 4) through exit or 36 wk PMA, % (n/N) | 10.0% (65/651) | 5.7% (22/385) | 16.2% (43/266) |
| Periventricular leukomalacia through exit or 36 wk PMA, % (n/N) | 4.1% (27/651) | 2.3% (9/385) | 6.8% (18/266) |
| Posthemorrhagic hydrocephalus through exit or 36 wk PMA, % (n/N) | 9.4% (61/651) | 4.7% (18/385) | 16.2% (43/266) |
| Early-onset septicemia (blood culture positive before 72 h of age), % (n/N) | 2.51% (18/717) | 0.52% (2/385) | 4.82% (16/332) |
| Late-onset septicemia (blood culture positive beyond 3 d of age) through exit up to 40 wk, % (n/N) | 20.39% (145/711) | 10.9% (42/385) | 31.60% (103/326) |
| Antibiotic courses of ⩾5 d duration without positive cultures through exit up to 40 wk, % (n/N) | 0.14%(1/717) | 0% (0/385) | 0.30% (1/332) |
| Retinopathy of prematurity (ROP): any stage/zone through exit up to 52 wk (of infants who received an ROP exam), % (n/N) |
57.1% (358/627) | 41.4% (154/372) | 80.0% (204/255) |
| Retinopathy of prematurity (ROP): severe (needing laser/bevacizumab/surgery) through exit up to 40 wk, % (n/N) | 7.9% (50/634) | 1.6% (6/372) | 16.8% (44/262) |
| Patent ductus arteriosus: any (diagnosed on echocardiography) through exit up to 40 wk, % (n/N) | 40.5% (263/650) | 31.2% (120/385) | 54.0% (143/265) |
| Patent ductus arteriosus: diagnosed through exit up to 40w and medically treated with indomethacin/ibuprofen/acetaminophen through exit up to 52 wk, % (n/N) | 26.9% (175/650) | 19.0 (73/385) | 38.5% (102/265) |
| Patent ductus arteriosus: surgically ligated or cardiac catheter closure through exit up to 40 wk, % (n/N) | 4.6% (30/650) | 1.0% (4/385) | 9.8% (26/265) |
| Necrotizing enterocolitis: medical (stage II or III) through exit up to 40 wk, % (n/N) | 4.8% (31/650) | 3.6% (14/385) | 6.4% (17/265) |
| Necrotizing enterocolitis: surgical (stage II or III) through exit up to 40 wk, % (n/N) | 3.4% (22/650) | 1.0% (4/385) | 6.8% (18/265) |
| Spontaneous intestinal perforation through exit up to 40 wk, % (n/N) | 3.1% (20/650) | 1.3% (5/385) | 5.7% (15/265) |
| Discharge weight, g, at exit up to 52 wk, mean ± SD; median; 25th–75th, n | 3,506.03 ± 1,162; 3,230; 2,611–4,125; n = 649 | 2,946.26 ± 706; 2,855; 2,390–351; n = 385 | 4,322.36 ± 1,213; 4,177.5; 3,347.5–5,120; n = 364 |
| Discharge weight percentile for PMA at exit up to 52 wk, mean ± SD; median; 25th–75th, n | 50.5 ± 28.6; 50.4; 25.5–75.2; n = 649 | 36.6 ± 23.5; 34.4; 16.4–55.2; n = 385 | 70.6 ± 22.9; 76.6; 55.2–89.2; n = 264 |
| Discharge length, cm, mean ± SD; median; range, n at exit up to 52 wk | 48.77 ± 4.67; 48; 45.5–51.50; n = 649 | 47.07 ± 3.63; 46.5; 44.5–49.50, n = 385 | 51.26 ± 4.9; 51; 48.0–54.5; n = 264 |
| Discharge length percentile for PMA, mean ± SD; median; 25th–75th, n at exit up to 52 wk | 50.6 ± 28.6; 48; 25.8– 75.2; n = 649 | 39.9 ± 25.2; 35.8; 17.3–59.9; n = 385 | 66.2 ± 26.0; 71.6; 48.0–88.3; n = 264 |
| Discharge head circumference, cm, at exit up to 52 wk, mean ± SD; median; 25th–75th, n | 34.57 ± 2.99; 34.5; 32.94–36.13; n = 649 | 33.35 ± 2.34; 33.5; 32–34.5; n = 385 | 36.34 ± 2.94; 36.0; 34.5–38.0; n = 264 |
| Discharge head circumference percentile for PMA at exit up to 52 wk, mean ± SD; median; 25th–75th, n | 50.4 ± 28.6; 53.5; 28.6–73.7; n = 649 | 38.6 ± 24.7; 37.0; 19.1–53.5; n = 385 | 67.7 ± 24.8; 72.5; 53.5–88.0, n = 264 |
| Hospital length of stay, d, mean ± SD; median; 25th–75th, n | 111 ± 44;199; 76–138; n = 649 | 86 ± 26; 83; 67–100; n = 385 | 148 ± 40; 145; 119–182; n = 264 |
Definition of abbreviations: BPD = bronchopulmonary dysplasia; CPAP = continuous positive airway pressure; IMV = invasive mechanical ventilation; NCPAP = nasal continuous positive airway pressure; NICHD = Eunice Kennedy Shriver National Institute of Child Health and Human Development; PMA = postmenstrual age; PPV = positive pressure ventilation.