Table 1.
Characteristics of the Infants at Baseline.*
| Characteristic | Hydrocortisone (N = 398) | Placebo (N = 402) |
|---|---|---|
| Maternal age — yr | 28.5±6.2 | 28.2±6.4 |
| Race — no./total no. (%)† | ||
| Black | 139/388 (35.8) | 168/391 (43.0) |
| White | 231/388 (59.5) | 206/391 (52.7) |
| Other | 18/388 (4.6) | 17/391 (4.3) |
| Hispanic or Latino ethnic group — no./total no. (%)† | 66/392 (16.8) | 60/397 (15.1) |
| Mother’s education — no./total no. (%) | ||
| Less than high school diploma | 68/396 (17.2) | 59/397 (14.9) |
| High school diploma | 101/396 (25.5) | 108/397 (27.2) |
| Partial college | 78/396 (19.7) | 85/397 (21.4) |
| College degree or more | 66/396 (16.7) | 69/397 (17.4) |
| Unknown | 83/396 (21.0) | 76/397 (19.1) |
| Received any antenatal glucocorticoids — no./total no. (%) | 343/395 (86.8) | 357/402 (88.8) |
| Birth weight — g | 710.3±162.7 | 720.4±171.8 |
| Gestational age — wk | 24.8±1.5 | 24.9±1.5 |
| Male sex — no (%) | 186 (46.7) | 235 (58.5) |
| Median 5-min Apgar score (5th to 95th percentile) | 6 (1–9) | 6 (2–9) |
| Small for gestational age — no. (%) | 46 (11.6) | 44 (10.9) |
| Multiple birth — no. (%) | 95 (23.9) | 102 (25.4) |
| 5-min Apgar score ≤5 — no./total no. (%) | 162/396 (40.9) | 155/397 (39.0) |
| Median no. of postnatal days at randomization (5th to 95th percentile) | 21 (14–28) | 21 (15–28) |
| Highest mode of support at trial entry — no./total no. (%) | ||
| High-frequency ventilator | 131/398 (32.9) | 119/401 (29.7) |
| Conventional ventilator | 265/398 (66.6) | 282/401 (70.3) |
| Nasal IPPV | 2/398 (0.5)‡ | 0/401 |
| Fio2 at trial entry | 0.52±0.21 | 0.50±0.20 |
| Respiratory index at trial entry§ | 596±350 | 569±319 |
*
Plus–minus values are means ±SD. Percentages may not total 100 because of rounding. Fio2 denotes fraction of inspired oxygen, and IPPV intermittent positive-pressure ventilation.
†
Race and ethnic group were reported by the parent or guardian.
‡
Infants were intubated at randomization but extubated before administration of hydrocortisone or placebo.
§
The respiratory index was calculated as mean airway pressure × Fio2 × 100.