Early postnatal dexamethasone may reduce poor respiratory outcomes in preterm infants

Key takeaways:

• Receiving dexamethasone after 5 weeks of age raised the odds for death and/or severe bronchopulmonary dysplasia.
• These infants were ventilated for longer vs. those who received treatment at 2 to 3 weeks old.

The odds for death and/or severe bronchopulmonary dysplasia went up in preterm infants who received postnatal dexamethasone after 5 weeks of age vs. at 2 to 3 weeks old, according to results published in European Respiratory Journal.

“This [study] provides a true reflection of current practices and valuable data for health care professionals caring for these infants during the neonatal stay and those in the post-discharge phase, including respiratory specialists,” T’ng Chang Kwok, BMedSci, BMBS, neonatal clinical research fellow in the division of child health, obstetrics and gynecology at University of Nottingham and Action Medical Research training fellow at The Alan Turing Institute, and colleagues wrote.

In a retrospective cohort study, Kwok and colleagues assessed 3,469 infants (median gestation at birth, 25 weeks; 60% boys) born before 32 weeks’ gestation in England and Wales between 2010 and 2020 who received postnatal dexamethasone to determine how the timing of the treatment impacts mortality and severe bronchopulmonary dysplasia (BPD) development.

A majority of the population (81%; n = 2,827) experienced the composite outcome of death and/or severe BPD, with 2,928 infants surviving to discharge. Respiratory support at discharge was necessary in 69% of these infants, according to researchers.

From 2010 to 2020, researchers found that postnatal dexamethasone was given at younger ages as time progressed (median, 28 days vs. 24 days; P < .001) and that more infants received multiple courses of this treatment (25% vs. 34%; P = .04).

Using propensity score weighting analysis (n = 3,032), researchers evaluated outcomes according to whether infants received postnatal dexamethasone at 2 to 3 weeks old (n = 1,098), 4 to 5 weeks old (n = 1,298) or after 5 weeks old (n = 636).

Researchers found similar odds for BPD between the three groups, but infants who received the treatment after age 5 weeks vs. at age 2 to 3 weeks faced greater odds for severe BPD (OR = 2.05; 95% CI, 1.55-2.71), death and/or developing severe BPD (OR = 1.68; 95% CI, 1.28-2.21) and had an increasing trend for needing respiratory support when discharged (OR = 1.34; 95% CI, 1.06-1.7).

Between these two age groups, researchers also observed that the group that received the treatment at an older age was ventilated for longer (mean difference, 17.5 days; 95% CI, 15.3-19.7 days) and underwent extubation at a later postmenstrual age (mean difference, 3.1 weeks; 95% CI, 2.9-3.4 weeks).

In contrast to these poor outcomes, infants who received postnatal dexamethasone after 5 weeks of age showed reduced odds for mortality before discharge vs. those who received the treatment at 2 to 3 weeks of age (OR = 0.38; 95% CI, 0.29-0.51).

Also, infants given dexamethasone at an age older than at 2 to 3 weeks had greater odds for extubation within 14 days of treatment (4-5 weeks, OR = 2; 95% CI, 1.6-2.4; after 5 weeks, OR = 2.6; 95% CI, 2-3.3).

Unlike treatment initiation after 5 weeks of age, researchers did not find links between postnatal dexamethasone given at 4 to 5 weeks old and severe BPD or discharge respiratory support.

“Although our study suggests that the optimal window for [postnatal dexamethasone] use was between 8 and 35 days chronological age, which is in line with previous smaller studies, residual confounding and survival bias cannot be excluded,” Kwok and colleagues wrote. “This highlights a need for both a definitive adequately powered clinical trial, including long-term outcomes, on the optimal timing for [postnatal dexamethasone] use and objective measures to support the early identification of high-risk infants for timely [postnatal dexamethasone] treatment.”