Spanish population‐study shows that healthy late preterm infants had worse outcomes one year after discharge than term‐born infants

Aim This study assessed the risks associated with healthy late preterm infants and healthy term‐born infants using national hospital discharge records. Method We used the minimum basic data set of the Spanish hospital discharge records database for 2012–2013 to analyse the hospitalisation of newborn infants. The outcomes were in‐hospital mortality and hospital re‐admissions at 30 days and one year after their first discharge. Results Of the 95 011 newborn infants who were discharged, 2940 were healthy late preterm infants, born at 34 + 0–36 + 6 weeks, and 18 197 were healthy term‐born infants. The mean and standard deviation (SD) length of hospital stay were 6.0 (4.5) days in late preterm infants versus 2.8 (1.3) days in term‐born infants (p < 0.001). Re‐admissions were also higher in the late preterm group at 30 days (9.0% versus 4.4%) and one year (22.0% versus 12.4) (p < 0.001). The relative risk for death at one year was 4.9 in the late preterm group, when compared to the term‐born infants (p = 0.026). Conclusion The hospital discharge codes for otherwise healthy newborn preterm infants were associated with significantly worse 30‐day and one‐year outcomes when their re‐admission and mortality rates were compared with healthy term‐born newborn infants.