Preemies exposed to some glucocorticoids have smaller cerebellar volumes

Glucocorticoids may affect cerebellar development in preterm newborns and thus should be used with caution in this population, say researchers in a new study of glucocorticoid exposure in neonates.

The American Academy of Pediatrics already recommends against the use of high-dose dexamethasone in neonates, but it has not issued a recommendation on the use of hydrocortisone.

Antenatal treatment with the glucocorticoid betamethasone is used routinely to enhance preterm lung maturation, and hydrocortisone and dexamethasone often are used postnatally for the treatment of persistent hypotension.

A decrease in cerebellar growth was associated with glucocorticoid use. On average, those neonates treated with hydrocortisone had a cerebellum that was 1.88 cm³ smaller and those treated with dexamethasone had a cerebellum that was 2.31 cm³ smaller by 40 weeks of postmenstrual age than those not exposed to glucocorticoids. Cerebellar volume was not associated with antenatal betamethasone exposure.

Among the study patients, 85% of preterm newborns were exposed to glucocorticoids antenatally, and 21% were exposed postnatally. "Clinicians caring for preterm newborns may need to weigh the benefits of using glucocorticoids for hypotension and prolonged intubation with these findings of associated impaired cerebellar growth," researchers write.

Tam EW, Chau V, Ferriero DM, et al. Preterm cerebellar growth impairment after postnatal exposure to glucocorticoids. Sci Transl Med. 2011;3(105):105ra105.