Deaths in preterm infants: changing pathology over 2 decades.

OBJECTIVE

To establish how cause of death for live-born preterm infants (24-31 weeks gestation) has changed in a single large UK population over 2 decades.

STUDY DESIGN

This was an interrogation of a population-based survey of >680, 000 live births (between 1988 and 2008) for deaths in the first postnatal year. We collected cause of death grouped into major etiologies: respiratory, infection, malformation, necrotizing enterocolitis (NEC), and other. Data were analyzed in three 7-year epochs and 2 gestational groups (<27 and 28-31 weeks). Numbers, rates per 1000 live births, and proportional contributions to each epoch were analyzed.

RESULTS

A total of 1504 deaths occurred. The infants who died had a median gestational age of 26 weeks (IQR, 25-28 weeks) and a median birth weight of 880 g (IQR, 700-1170 g). The number of deaths decreased with each later epoch (from 671 to 473 and then to 360), as did the proportion of deaths from respiratory causes (64% to 62% and then to 49%). The proportion of deaths occurring after 40 weeks postmenstrual age remained stable across the 3 epochs (8.8%, 8%, and 8%). Deaths from infection and NEC increased with time (from 11% to 13% and then to 21%), as did median time to death (from 2.7 to 3.8 days).

CONCLUSION

Infection and NEC are increasingly prevalent causes of death in preterm infants.