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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Neurodevelopmental outcomes of extremely low birth weight infants <32 weeks' gestation between 1993 and 1998
Betty R Vohr1, Linda L Wright, W Kenneth Poole
1Department of Pediatrics, Women and Infants Hospital, Providence, RI 02905, USA. Betty_Vohr@brown.edu
Insights
Improvements in perinatal care over three epochs (1993-1998) enhanced survival for extremely low birth weight infants. Antenatal steroids were linked to better neurodevelopmental outcomes, reducing impairment rates.
Area of Science:
- Neonatalogy
- Perinatal Medicine
- Developmental Pediatrics
Background:
- Extremely low birth weight (ELBW) infants face significant risks for neurodevelopmental impairment (NDI).
- Changes in perinatal management protocols may influence ELBW infant outcomes.
- The Neonatal Research Network tracked ELBW infant outcomes across distinct care epochs.
Purpose of the Study:
- To evaluate the impact of evolving perinatal management on NDI in ELBW infants.
- To assess outcomes for both low (22-26 weeks) and higher (27-32 weeks) gestation ELBW infants.
- To determine if outcomes improved across three study epochs (1993-1998).
Main Methods:
- A multicenter cohort study of 3785 ELBW infants assessed at 18-22 months corrected age.
- Regression analyses examined epoch effects, gestational age, and intervention impacts.
- Key interventions analyzed included antenatal steroids, high-frequency ventilation, nutritional intake markers, and postnatal steroids.
Main Results:
- Infant survival improved across epochs for both gestational age groups.
- Epoch 2 showed reduced risk for adverse outcomes, including low Bayley Mental Development Index (MDI) and NDI, compared to Epoch 1.
- Antenatal steroids were associated with decreased risk of cerebral palsy (CP) and low Bayley Psychomotor Development Index; postnatal steroids were linked to increased NDI.
Conclusions:
- ELBW infant survival and neurodevelopmental outcomes improved between 1993 and 1998.
- While some outcomes remained stable, rates of low MDI scores and NDI decreased.
- Antenatal steroid administration emerged as the sole intervention significantly associated with improved outcomes.
Objective:
This study evaluated the impact of changes in perinatal management on neurodevelopmental impairment (NDI) at 18 to 22 months' corrected age of low gestation (22-26 weeks) and higher gestation (27-32 weeks) extremely low birth weight infants (401-1000 g birth weight) who were cared for in the National Institute of Child Health and Human Development Neonatal Research Network during 3 epochs (1993-1994, 1995-1996, and 1997-1998). It was hypothesized that outcomes would improve over the 3 epochs.
Methods:
A multicenter cohort study was conducted of the outcomes of 3785 infants with assessments at 18 to 22 months' corrected age. Regression analyses were completed to evaluate for epoch effects, gestational age effects, and time plus gestational age interaction. Regression analyses were also performed to identify the independent associations of epoch and 4 study perinatal interventions: antenatal steroids (yes, no), high-frequency ventilation (yes, no), number of days to regain birth weight as a marker of nutritional intake, and postnatal steroids for treatment of bronchopulmonary dysplasia (yes, no) with outcomes.
Results:
Survival improved for both the low (55%-61%) and higher (82%-86%) gestational age groups during the 3 epochs. Regression analyses indicated that the decreased risk for adverse outcome was significantly lower in epoch 2 compared with epoch 1 with decreased rates of low Bayley Mental Development Index (MDI) and neurodevelopmental impairment (NDI). Antenatal steroids were associated with decreased risk for moderate to severe cerebral palsy (CP) and low Bayley Psychomotor Development Index. High-frequency ventilation was associated with a low Bayley MDI and NDI, and postnatal steroids were associated with moderate to severe CP, any CP, low Bayley MDI, low Bayley Psychomotor Development Index, and increased NDI.
Conclusion:
Survival of extremely low birth weight infants improved between 1993 and 1998. Although some outcomes remained unchanged, the rates of low Bayley MDI scores and NDI improved. Antenatal steroid administration was the only study intervention associated with improved outcomes.
