Vitamin D abnormalities and bone turn over analysis in children with epilepsy in the Western Cape of South Africa.

Affiliation

Department of Paediatric Neurology, Red Cross War Memorial Children's Hospital, Neuroscience Institute, University of Cape Town, South Africa; Department of Paediatrics and Child Health, Muhimbili University of Health and Allied Sciences, Dar Es Salaam, Tanzania. Electronic address: [Email]

Abstract

OBJECTIVE : The effects of antiseizure medications (ASMs) on bone metabolism is inconsistent. Most studies are in high income settings and none from sub-Saharan Africa.
METHODS : A hospital based cross-sectional study in a paediatric epilepsy service with a comparison group assessed vitamin D metabolism.
RESULTS : Seventy-five children with epilepsy and 75 comparison group were recruited. Median age for children with epilepsy was 9 years (range 1-17 years) and controls 3 years (range 1-12 years). Vitamin D deficiency occurred in 11(16.2%) children with epilepsy versus 6 (8.8%) control group (p = 0.29). Vitamin D insufficiency occurred in 30 (44.1%) children with epilepsy compared to 27(39.7%) control group. Children on ASMs had lower mean vitamin D levels than the control group (p = 0.02). Children on enzyme-inducing ASMs had lower mean vitamin D levels (p = 0.08), vitaminD2 (p = 0.0018), vitaminD3 (p = 0.004), serum phosphate levels (p = 0.000), and higher mean parathyroid hormone levels (p = 0.03) compared to controls. There was no difference in dietary intake and ancestry, although the dietary content of both groups was low in vitamin D products.
CONCLUSIONS : Low vitamin D levels were common in children from both groups, but statistically lower for the children on ASMs. Children on enzyme-inducing ASMs need screening for vitamin D deficiency. The literature supports extending this for all children on ASMs. This is the first study to report that children on enzyme-inducing ASMs have lower levels of Vitamin D2 and D3 levels, probably as result of increased destruction of vitamin D. Improved vitamin D intake for children in vulnerable settings is important.

Keywords

Africa,Antiseizure medications,Bone mineral metabolism,Children,Epilepsy,Vitamin D,