TABLE 5.
Risk of In-Hospital Morbidities for VLBW Infants in the NRN Cohort Born 1998–2007 With and Without a Major BD Who Survived > 3 Days
| Outcome, N (%)a | Infants With BDs | Infants Without BDs | Adjusted RR for Morbidity (95% CI) BD Versus No BDb | P b |
|---|---|---|---|---|
| Infants who survived > 3 d | N = 1315 | N = 32 065 | — | — |
| PDA | 686 (52) | 10 394 (32) | 2.01 (1.89–2.13) | <.001 |
| RDS | 1008 (77) | 24 266 (76) | 1.16 (1.13–1.20) | <.001 |
| NEC | 135 (10) | 2492 (8) | 1.59 (1.35–1.88) | <.001 |
| LOS | 375 (29) | 7609 (24) | 1.53 (1.41–1.67) | <.001 |
| Infants who had a cranial sonogram within 28 dc | N = 1196 | N = 30 094 | — | — |
| Severe ICH | 136 (11) | 3253 (11) | 1.41 (1.20–1.65) | <.001 |
| Infants with a cranial sonogram within 28 d and/or closest to 36 wk PMAd | N = 1220 | N = 30 351 | — | — |
| PVL | 67 (5) | 1163 (4) | 1.71 (1.35–2.17) | <.001 |
| Infants with sufficient information to include in analysise | N = 1194 | N = 30 078 | — | — |
| Severe ICH or PVL | 174 (15) | 3788 (13) | 1.50 (1.30–1.72) | <.001 |
| Infants still in the hospital at 28 d who had a ROP examination | N = 819 | N = 22 414 | — | — |
| ROP | 344 (42) | 10 519 (47) | 1.12 (1.04–1.21) | .003 |
| ROP stage 3 or higher | 78 (10) | 2563 (11) | 1.25 (1.02–1.53) | .05 |
| Infants born <36 wk GA who were evaluated for BPDf | N = 1016 | N = 29 241 | — | — |
| BPD | 463 (46) | 8185 (28) | 1.93 (1.79–2.08) | <.001 |
Information was missing for PDA: 9 infants; RDS: 45; NEC: 5; LOS: 32; ICH: 21; PVL: 12; ICH or PVL: 299; ROP: 4; ROP stage 3+: 16; BPD: 135 infants. The majority with missing information were infants with no major BD. One infant with a BD who died with unknown death date was excluded from survivors >3 d.
RRs, CIs, and P values by the Score test from modified Poisson regression models fit to each outcome that included study center, GA (<25, 25–28, 29–32, 33+), SGA, male gender, race (African American, non-African American), and the BD indicator. On rows showing numbers of infants, adjusted RRs and P values are not applicable and are not shown as indicated by dashes.
Severe ICH was defined as grade 3 or 4 and was diagnosed based on the cranial sonogram taken within 28 days of birth with the most severe results.
PVL was determined based on a sonogram taken within 28 days of birth and/or a sonogram taken closest to 36 weeks PMA (specified as after 28 days beginning in 2006).
Percents were based on infants with nonmissing ICH and PVL outcomes, except that a diagnosis of either condition was sufficient to set the outcome to yes. Thus, percents were based on a sonogram taken within 28 days of birth and/or a sonogram taken closest to 36 weeks PMA (specified as after 28 days beginning in 2006).
BPD was defined for infants born <36 weeks’ GA as the need for supplemental oxygen use at 36 weeks PMA. For infants discharged or transferred before 36 weeks PMA, BPD was defined based on oxygen use at 36 weeks if known, or oxygen use at the time of discharge or transfer.