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Anti-Epileptic Drugs Increase Bone Fracture Risk in Children

New research has shown evidence that anti-epileptic drugs (AEDs) reduce bone density in children and therefore lead to an increase in the number of fractures if used for more than a year. The study, published in Epilepsia (, has prompted experts to highlight the importance of considering side-effects when prescribing these drugs.

One in 150 children are diagnosed with epilepsy in the first decade of life in Australia, but there is currently very little paediatric data relating to the impact of AEDs on the health of their bones. Researchers from the Murdoch Children’s Research Institute in conjunction with the Royal Melbourne Hospital undertook a case-controlled study using 23 pairs of twins, non-twin siblings and first cousins – one with epilepsy and one without.

Those who were taking AEDs had an increased prevalence of bone fractures, with 15 fractures in eight subjects compared with only four fractures in those who didn’t take the medication. The study also analysed each subject’s bone density and found that one important measure of bone density was 14% lower in the group taking AEDs.

“We need further research to confirm our findings, but our preliminary study suggests that all young people on these agents should remain active wherever possible, and keep up their calcium intake and vitamin D levels,” said Dr Peter Simm of the Murdoch Children’s Research Institute.

There are greater long-term implications for growing children on AEDs, as the period between the age of 12 and the early twenties is a critical period for the accrual of bone to adult levels. Children currently on AEDs are being encouraged to take proactive steps towards countering its effects, such as nutrition, exercise and physiotherapy in severe cases to avoid ongoing problems later in life.

Researchers are still working to discover if it is the muscle or bones that are directly affected and cause these detrimental effects to bone health. Longitudinal studies are required to confirm these changes in the muscle–bone unit to determine the effect of individual AEDs on bone health and to further explore the clinical outcomes.