Survival and major neurodevelopmental impairment in extremely low gestational age newborns born 1990–2000: a retrospective cohort study
Lisa K Washburn1, Robert G Dillard1, Donald J Goldstein1, Kurt L Klinepeter1, Raye-Ann deRegnier2 and Thomas Michael O'Shea1
1Department of Pediatrics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
2Department of Pediatrics, Northwestern University School of Medicine, Chicago, IL, USA
It is important to determine if rates of survival and major neurodevelopmental impairment in extremely low gestational age newborns (ELGANs; infants born at 23–27 weeks gestation) are changing over time.
Study infants were born at 23 to 27 weeks of gestation without congenital anomalies at a tertiary medical center between July 1, 1990 and June 30, 2000, to mothers residing in a thirteen-county region in North Carolina. Outcomes at one year adjusted age were compared for two epochs of birth: epoch 1, July 1, 1990 to June 30, 1995; epoch 2, July 1, 1995 to June 30, 2000. Major neurodevelopmental impairment was defined as cerebral palsy, Bayley Scales of Infant Development Mental Developmental Index more than two standard deviations below the mean, or blindness.
Survival of ELGANs, as a percentage of live births, was 67% [95% confidence interval: (61, 72)] in epoch 1 and 71% (65, 75) in epoch 2. Major neurodevelopmental impairment was present in 20% (15, 27) of survivors in epoch 1 and 14% (10, 20) in epoch 2. When adjusted for gestational age, survival increased [odds ratio 1.5 (1.0, 2.2), p = .03] and major neurodevelopmental impairment decreased [odds ratio 0.54 (0.31, 0.93), p = .02] from epoch 1 to epoch 2.
The probability of survival increased while that of major neurodevelopmental impairment decreased during the 1990's in this regionally based sample of ELGANs.
During the 1980's and early 1990's, improvements in perinatal care resulted in an increased rate of survival for extremely low gestational age newborns (ELGANs; infants 23–27 weeks) . Despite some evidence that increased survival of ELGANs may be accompanied by an increased rate of disability [2,3], most reports suggest that this is not the case [4-8]. Continuing increases in the rate of survival of extremely premature infants have been reported during the late 1990's [9,10], but more information is needed regarding changes in outcome related to improved survival.
The aim of the study was to investigate whether survival in a geographically based sample of ELGANs increased during the 1990's, and if so, whether this increase was accompanied by an increased rate of major neurodevelopmental impairments among survivors.
BMC Pediatrics 2007, 7:20. This is an Open Access article distributed under the terms of the Creative Commons Attribution License.