October 19, 2011

expert reaction to new research into the use of steroids to treat premature babies, as published in the journal Science Translational Medicine

New research assessed the value of using steroids to treat premature babies.

Simon Keady, Chair of the Neonatal and Paediatric Pharmacists Group, said:

“This paper reinforces the challenges faced by doctors treating premature babies in their first weeks of life. Immediate treatment decisions need to be made and whilst it is comforting to see that betamethasone has no impact on brain size, the effects of dexamethasone and hydrocortisone appear to have some effect on development. It is reassuring that the authors of the paper will undertake a physical follow up of these babies as they reach school age to show what the reduction in size of this part of the brain size actually means in real terms.

“The side effects of these drugs are known and form part of the decision that doctors have to make in order to try to aid survival. However, these drugs are only used for the shortest length of time and lowest doses necessary. It’s important there’s further research into more effective drugs which, whilst increasing the chances of a baby’s survival, reduce any long term side effects associated with their use.”

Prof David Edwards, Director, Centre for the Developing Brain, Imperial College London, said:

“This careful research adds to the evidence that babies who receive intensive care because of premature birth can have reduced brain growth, in this case in the cerebellum. It is now important to find out if this is associated with long-term problems because we already know that reduced growth in the cerebral cortex over this period predicts childhood abilities.”

Prof Andrew Whitelaw MD FRCPCH, Professor of Neonatal Medicine, University of Bristol, said:

“Hydrocortisone and dexamethasone are used to treat two life threatening complications of severe preterm birth, namely low blood pressure and chronic lung disease. We have known for a number of years that high dose dexamethasone can injure the brain and increased disability and neonatologists have avoided this in recent years. We had hoped that low dose dexamethasone and hydrocortisone would still be life-saving without increasing brain injury and both these drugs have been used in many UK neonatal intensive care units. When discussing possible use of dexamethasone with parents of babies who might die of lung disease we have always discussed a possible increase in brain injury and disability as an alternative to death.

“This new study by Dr Tam shows that even low dose dexamethasone and hydrocortisone reduce growth of the cerebellum but not of the brain as a whole. The cerebellum is important for cognition as well as control of movement and may be particularly vulnerable as it normally grows rapidly during the period when the steroids are given. We don’t yet know how much difference a 10 % decrease in cerebellum will make to the child’s later development but I think this is likely, based on our own and others’ research.

“The good news is that this study did not show any adverse effect when betamethasone was given to the mother shortly before premature delivery.

“I believe this new evidence will make neonatologists even more restrictive in the use of steroids for premature babies with life-threatening chronic lung disease and especially for treating low blood pressure where there are other treatments. In a few babies the baby’s own production of steroids fails and then steroid drugs have to be given as replacement just to restore normality.”

‘Preterm Cerebellar Growth Impairment After Postnatal Exposure to Glucocorticoids’, Tam et al, published in Science Translational Medicine on Weds 19 Oct.