BETHESDA, Md. A treatment commonly used to reduce the risk
of chronic lung disease in extremely premature infants does not reduce the risk
of death or chronic lung disease in these infants and may increase the risk for
perforation of the intestines, according to a new study.
In the largest, most comprehensive study of its kind, the
researchers concluded that early postnatal doses of dexamethasone are not
indicated to prevent lung disease in extremely low birth weight infants. The
study by the National Institute of Child Health and Human Development (NICHD)
Neonatal Research Network appeared recently in the New England Journal of
shows that early moderate doses of dexamethasone do not increase the survival
of preterm infants or prevent chronic lung disease and may actually endanger
their health, said NICHD Director, Duane Alexander, MD.
Approximately 70% of extremely low birth weight infants (weighing
<1 kg) survive to hospital discharge. Of these, about 30% develop chronic
lung disease requiring supplemental oxygen. The incompletely developed lungs of
these infants, most of whom are extremely premature, are easily injured by
mechanical ventilators, oxygen and infection.
In addition, there is preliminary evidence that these infants
have inadequate levels of the stress hormone cortisol, which may make them
susceptible to an exaggerated response to injury and infection. Cortisol plays
a role in switching off an immune response after an infection or
other threat has subsided.
Attempt to reduce chronic lung
Some studies have suggested that dexamethasone given from 24 to
48 hours after birth may reduce the risk for chronic lung disease. The
anti-inflammatory drug, dexamethasone is chemically resembles cortisol and is
often prescribed to dampen the inflammatory response that causes lung damage in
However, infants in these studies were typically given large
doses of the drug, which interfered with the infants growth and increased
their blood sugar and blood pressure.
In all, the researchers enrolled 220 infants from the 13 centers
taking part in the trial. Roughly half were treated with dexamethasone and half
with a placebo.
Fewer infants in the dexamethasone group needed oxygen therapy
after 28 days but this advantaged disappeared by 36 weeks of age. However,
significantly more infants in the dexamethasone group than the control group
(13% vs. 4%) developed spontaneous perforation of the intestines. After review
of the data by the trials data and safety monitoring committee, the
researchers terminated the trial early.
Given these serious complications and the lack of
discernible benefit, the researchers wrote, we think that early
dexamethasone treatment to prevent chronic lung disease in extremely low birth
weight infants is not indicated.
For more information:
- Stark AR, Carlo WA, Tyson JE, et al. Adverse effects of
early dexamethasone treatment in extremely-low-birth-weight infants. N
Engl J Med. 2001;344:95-101.