Interpretation
Antenatal corticosteroids for preterm birth have shown to reduce
neonatal morbidity and
mortality10 are
cost-effective85, and
are routinely recommended
worldwide.7,86,87The Cochrane review,10and our review are aligned with these studies and recommendations.
The other Cochrane
review,9 comparing both
corticosteroids, did not include recent evidence. The new trial
ASTEROID12, almost
doubled the number of included women under direct comparisons, provided
information for our main outcomes, improved the precision for
neurosensory disability estimates, and unlike that it was believed it
found that dexamethasone may have a beneficial effect on
chorioamnionitis.
The potential beneficial effect of dexamethasone on IVH suggested by
very low-CE, was reduced with the inclusion of the ASTEROID
trial12 and completely
disappeared when excluding Elimian
2007.46 This post-hoc
sensitivity analysis, based on the very high risk of attrition bias of
this study, provided more consistent results with the indirect evidence.
Additionally, a meta-analyses found an increased risk of
neurodevelopmental impairment in children with
periventricular/intraventricular
haemorrhage88, mainly
driven by cerebral
palsy89. Since we did
not find a differential effect of dexamethasone on neurosensory
disability it would be unlikely a favourable effect on IVH.
Additionally, even if a reduction in IVH was true, it is more important
the observed absence of differences on long-term disability for the
quality of life of
survivors.90
Roberts 200611 assessed
indirect estimations favouring betamethasone for chorioamnionitis. This
was consistent with our indirect estimation but opposite to the ASTEROID
trial12 findings that
were considered the most reliable estimation for this outcome.
Our NMA improved the precision and certainty of most previous
estimations. We identified a another NMA that evaluated antenatal
maternal administration dexamethasone, betamethasone and ambroxol to
prevent RDS.91 Compared
with placebo, all interventions reduced RDS and neonatal death, but no
significant difference in the incidence of bronchopulmonary dysplasia.
They also suggest that ambroxol seems to be the most effective treatment
for reducing the incidence of RDS and neonatal death based on its SUCRA
values. This conclusion was not consistent with a Cochrane
review92 or the
relevant preterm birth management
guidelines.7,86
A wise choice should consider all factors besides evidence, including
local availability, costs and
cost-utility.93,94A full course of betamethasone costs around US$35 while dexamethasone
$1 (3% of the cost of
betamethasone).94 The
cost-effectiveness of the administration of betamethasone based in
individual trials is controversial, and it should be based in the best
estimation of
effectiveness.95,96Mainly LMICs still have significant challenges to provide safe and
effective antenatal corticosteroid use, including ensuring accurate
gestational age determination, establishing clear treatment guidelines,
strengthening provider capacity, incorporating corticosteroid in
national essential medicines lists, and monitoring use and
outcomes.97