Predicting Survival Without Disability Among Preterm Infants

A recent article (J Bourke et al. .J Pediatr 2019; 215: 90-7) made me wonder if my outlook on disability-free survival of preterm infants has been skewed by the population that I encounter.  That is, the outcomes from this large Australia study were better than I would have guessed.

This retrospective cohort study identified 720.091 live births from 1983-2010; in this group, 12,083 were diagnosed with a disability and 5,662 died. The authors sought to determine rates of intellectual disability or autism as identified by the IDEA (Intellectual Disability Exploring Answers) database.  Because this is a retrospective study, it did not capture milder and more common neurodevelopmental disorders like attention deficit hyperactivity disorder.

Key findings:

The probability of disability-free survival to 25 years was the following:

  • 4.1% for those born at 22 weeks gestation
  • 19.7% for those born at 23 weeks gestation
  • 42.4% for those born at 24 weeks gestation
  • 53.0% for those born at 25 weeks gestation
  • 78.3% for those born at 28 weeks gestation
  • 97.2% for those born full term (39-41 weeks)

Risk factors for lower rates of disability-free survival:

  • Aboriginal population (instead of Caucasian), low Apgar score, male sex, low socioeconomic status, and remote region of residence

My take: This data shows the marked improvement in outcomes with longer gestation age.