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Actuarial survival in the premature infant less than 30 weeks' gestation
T R Cooper1, C L Berseth, J M Adams
1Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA.
Insights
Actuarial survival for premature infants (<30 weeks gestation) significantly improves in the first days and weeks of life. However, the smallest premature infants still face a notable risk of late death.
Area of Science:
- Neonatalogy
- Perinatology
- Pediatric Survival Analysis
Background:
- Current survival metrics for premature neonates (<30 weeks gestation) do not adequately inform about long-term life expectancy.
- Actuarial survival, representing future life expectancy from a specific postnatal age, offers a more comprehensive outlook.
Purpose of the Study:
- To characterize the actuarial survival rates in a large cohort of inborn premature infants.
- To provide better data for parents and physicians regarding the future life expectancy of premature neonates.
Main Methods:
- A retrospective analysis of 1925 inborn infants (23-29 weeks gestation) admitted between July 1986 and December 1994.
- Data were stratified by 100-g birth weight intervals and 1-week gestational age intervals.
- Daily actuarial survival was calculated for each stratum.
Main Results:
- In the 501-600g birth weight group, actuarial survival increased from 31% at birth to 61% by day 7 and 75% by day 28.
- In the 901-1000g birth weight group, survival improved from 88% at birth to 94% by day 7 and 98% by day 28.
- Similar positive trends in survival were observed when data were stratified by gestational age.
Conclusions:
- Actuarial survival shows dramatic improvement in the initial days of life for the smallest premature infants.
- Despite improvements, a significant risk of late death persists for the most premature neonates.
- These findings highlight the need for continued monitoring and care for extremely preterm infants.
Objective:
Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation.
Study Design:
We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals.
Results:
In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age.
Conclusions:
Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants.
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