Study: A multicenter, randomized, double-blind, placebo-controlled trial.
Subjects: Neonates 3 to 14 days old, with gestational age < 33 weeks
and birthweight less than 1250 grams and need for mechanical ventilation.
Criteria: Evidence of sepsis, glucose intolerance, hypertension, necrotizing
enterocolitis, renal insufficiency, abnormal liver function, major congenital
anomalies, or prior systemic glucocorticoid therapy.
Methods: Beclovent (beclomethasone dipropionate) and placebo metered
dose inhalers were used with Aerochamber device delivered via endotracheal
tube. The dose was decreased gradually over four weeks from 40 mcg/kg/day
to 5 mcg/kg/day. Systemic glucocorticoids could be initiated at the
discretion of the attending physician if the neonate had increasing
oxygen requirements for at least 5 days and received the study drug
at least 7 days.
Main Results: By 28 days or 36 weeks corrected gestational age in neonates
who took inhaled beclomethasone, there was no difference in mortality
or frequency of BPD, but fewer infants were receiving systemic glucocorticoids,
and there was a 50% reduction in systemic steroid use after confounding
factors were considered (gestational age, antenatal steroid use, or
oxygenation index) (1).
Validity: This was a well designed study with many patients, and statistical
analyses accounted for many potentially confounding variables. Yet a
major confounder-the frequency of use of systemic glucocorticoids-was
not accounted for in the ultimate results of the study. Because more
of the placebo group received the systemic steroids, those patients
were then less likely to be diagnosed with BPD.