Related Experiment Video
Updated: Aug 11, 2026
Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats
Published on: November 20, 2015
Increasing illness severity in very low birth weight infants over a 9-year period
David A Paul1, Kathleen H Leef, Robert G Locke
1Department of Pediatrics, Christiana Care Health Services, Newark, DE, USA. paul.d@christianacare.org
Insights
Illness severity in very low birth weight (VLBW) infants increased from 1993-2002, leading to more deaths and severe intraventricular hemorrhage (IVH). This suggests a shift in care towards more compromised neonates surviving fetal development.
Area of Science:
- Neonatalogy
- Perinatal Medicine
- Pediatric Critical Care
Background:
- Survival rates for preterm infants plateaued in the 1990s.
- Investigated temporal changes in illness severity for very low birth weight (VLBW) infants.
Purpose of the Study:
- To determine changes in VLBW infant illness severity over time.
- To correlate illness severity with outcomes of death and/or severe intraventricular hemorrhage (IVH).
Main Methods:
- A cohort study of 1414 VLBW infants from 1993-2002.
- Illness severity measured by Score for Neonatal Acute Physiology (SNAP) and total thyroxine (T4).
- Analyzed death before discharge and severe IVH in relation to illness severity.
Main Results:
- Illness severity (SNAP, T4) increased steadily from 1993-2002.
- Increased severity correlated with higher rates of severe IVH and combined death/severe IVH.
- Fetal death rate decreased significantly over the study period.
Conclusions:
- Progressive increase in VLBW infant illness severity is linked to increased death and/or severe IVH.
- This may indicate a shift of more compromised infants surviving fetal development into neonatal care.
- Neonatal intensive care units may be seeing an influx of higher-risk VLBW infants.
Background:
Recent reports have documented a leveling-off of survival rates in preterm infants through the 1990's. The objective of this study was to determine temporal changes in illness severity in very low birth weight (VLBW) infants in relationship to the outcomes of death and/or severe IVH.
Methods:
Cohort study of 1414 VLBW infants cared for in a single level III neonatal intensive care unit in Delaware from 1993-2002. Infants were divided into consecutive 3-year cohorts. Illness severity was measured by two objective methods: the Score for Neonatal Acute Physiology (SNAP), based on data from the 1st day of life, and total thyroxine (T4), measured on the 5th day of life. Death before hospital discharge and severe intraventricular hemorrhage (IVH) were investigated in the study sample in relation to illness severity. The fetal death rate was also investigated. Statistical analyses included both univariate and multivariate analysis.
Results:
Illness severity, as measured by SNAP and T4, increased steadily over the 9-year study period with an associated increase in severe IVH and the combined outcome of death and/or severe IVH. During the final 3 years of the study, the observed increase in illness severity accounted for 86% (95% CI 57-116%) of the variability in the increase in death and/or severe IVH. The fetal death rate dropped from 7.8/1000 (1993-1996) to 5.3/1000 (1999-2002, p = .01) over the course of the study.
Conclusion:
These data demonstrate a progressive increase in illness in VLBW infants over time, associated with an increase in death and/or severe IVH. We speculate that the observed decrease in fetal death, and the increase in neonatal illness, mortality and/or severe IVH over time represent a shift of severely compromised patients that now survive the fetal time period and are presented for care in the neonatal unit.
Related Concept Videos
01:30Development of Human Microbiota
01:18Factors Affecting Illness
For instance, risk factors are connected to illness, disability,...