Dexamethasone safer than betamethasone for preterm neonates?

According to the results of a trial published in Obstetrics and Gynecology, the use of antenatal dexamethasone is associated with a lower rate of neonatal intraventricular haemorrhage than betamethasone, although both agents are effective at reducing overall neonatal morbidity and mortality.

In the double-blind Antenatal Betamethasone Compared with Dexamethasone (Betacode) trial, investigators randomised women at risk for preterm delivery to treatment with antenatal betamethasone (n=100) or dexamethasone (n=105). Exclusion criteria included clinical chorioamnionitis, foetal structural and chromosomal abnormalities, prior antenatal steroid exposure, and steroid use for other indications.

The main results were as follows:

• There were no significant differences between the groups in rate of respiratory distress syndrome, need for vasopressor therapy, necrotising enterocolitis, retinopathy of prematurity, patent ductus arteriosus, neonatal sepsis, and neonatal mortality
• There were 6 cases of intraventricular haemorrhage in infants of the 105 women randomised to dexamethasone (5.7%) compared with 17 cases among infants of the 100 women treated with antenatal betamethasone (17.0%) (RR 2.97, 95% CI 1.22-7.24, P=0.02). Dexamethasone was therefore associated with an absolute risk reduction in the rate of intraventricular haemorrhage of 11.3 % (95% CI 2.7-11.9%), with a number needed to treat of 9 (95% CI 5-37).
• There were 6 brain lesions of any kind (6.7%) in infants of women receiving dexamethasone and 18 cases of any type of brain lesion in the infants of women receiving betamethasone (18.0%) (RR 2.7, 95% CI 1.18-6.19, P=0.02)

The authors state that their study "largely supports the continuing use of both betamethasone and dexamethasone in the treatment of women at risk of preterm delivery…However, dexamethasone seems to be more effective in reducing the rate of intraventricular haemorrhage compared with betamethasone”.

An accompanying editorial discusses the study.

[Editor's note: this summary was taken from the abstract only, as the full text was not accessible at the time of posting]

Obstet Gynecol 2007; 110: 26-30 (link to abstract) Obstet Gynecol 2007; 110: 7-9 (editorial; link to full text, available to subscribers only)