Table 1.
Clinical population characteristics
| Severe ROP(n = 8) | No or mild ROP (n = 217) | p value | |
|---|---|---|---|
| Maternal and gestational characteristics | |||
| Multiple gestation | 2 (25) | 53 (24) | 0.970 |
| Maternal PE ± HELLP syndrome | 1 (13) | 31 (14) | 0.887 |
| Antenatal MgSO4 | 5 (63) | 157 (75) | 0.421 |
| Histologic chorioamnionitis | 1 (14) | 85 (44) | 0.116 |
| Delivery by caesarian section | 6 (75) | 107 (49) | 0.154 |
| Neonatal characteristics | |||
| Gender, male | 4 (50) | 101 (47) | 0.847 |
| Gestational age, weeks | 26.5 [25.3 to 28.1] | 28.0 [26.7 to 29.0] | 0.083** |
| Birth weight, g | 745 [620 to 773] | 1,000 [800 to 1,300] | 0.002* |
| Birth weight (z-score) | −1.49 [–5.02 to −0.47] | −0.89 [–1.93 to −0.15] | 0.155 |
| Small-for-gestational age | 3 (38) | 52 (24) | 0.382 |
| Head circumference, cm | 23 [22 to 24] | 26 [24 to 27] | 0.002* |
| Head circumference (z-score) | −1.29 [–3.12 to −0.06] | −0.70 [–1.36 to −0.07] | 0.282 |
| Apgar score at 5 min | 7 [6 to 8] | 7 [6 to 8] | 0.883 |
| Mechanical ventilation | 8 (100) | 163 (75) | 0.106 |
| Duration of mechanical ventilation, days | 18 [7 to 26] | 2 [1 to 10] | 0.006* |
| hsPDA | 3 (38) | 90 (42) | 0.823 |
| Necrotizing enterocolitis | 3 (38) | 31 (14) | 0.072** |
| Sepsis | 1 (13) | 72 (33) | 0.220 |
| RBC transfusions | 7 (88) | 142 (66) | 0.200 |
| Intraventricular hemorrhage | |||
| Grade I/II | 2 (25) | 55 (25) | 0.982 |
| Grade III/IV | 0 (0) | 9 (4) | 0.557 |
| BPD | 6 (75) | 81 (37) | 0.032* |
| Dexamethasone treatment | 4 (50) | 31 (14) | 0.006* |
| Death before discharge | 0 (0) | 6 (3) | 0.634 |
Data are presented as medians [interquartile range] or absolute numbers (percentages). BPD, bronchopulmonary dysplasia (defined as the need for oxygen ≥21% for ≥28 days at 36 weeks postmenstrual age or discharge); HELLP, Hemolysis, Elevated Liver enzymes (>70 iU/L) and Low Platelets (<100 × 106); hsPDA, hemodynamically significant (i.e., treatment-requiring) patent ductus arteriosus; MgSO4, magnesium sulfate; RBC, red blood cell; ROP, retinopathy of prematurity; PE, preeclampsia (defined as pregnancy induced hypertension with proteinuria [protein to creatinine ratio ≥0.3 g/10 mmol or 0.3 g in 24-h urine]).
and
Difference between infants with and without severe ROP at the 5 and 10% significance level, respectively, as tested with Mann-Whitney U or t test.