Serum Calcium, Vitamin D3 and Bone Specific Alkaline Phosphatase Levels in Nigerian Children Treated with Antiepileptic Drugs: A Comparative Study

Background and Aim of the Study: Studies have shown that serum 25-hydroxycholecalciferol, calcium and bone-specific alkaline phosphatase (B-ALP) are altered in children on antiepileptic drugs (AEDs), and these could result in poor bone mineralization. The study aimed to determine the serum 25-hydroxycholecalciferol, calcium, and B-ALP levels among children on AEDs attending the paediatric neurology clinic of the University of Port Harcourt Teaching Hospital (UPTH).

Methods: This cross-sectional analytical study was carried out from January 2018 to April 2019 on 100 children on AEDs and 100 age- and gender-matched healthy controls, aged 1.5 - 17 years. Data on socio-demography, AED regimen, and clinical examination findings of the subjects, their serum 25-hydroxycholecalciferol, calcium, and B-ALP levels were obtained and entered into a proforma. Data obtained were analysed using IBM SPSS version 20. Statistical significance was set at p-value of < 0.05.

Results: The subjects had significantly lower mean serum 25-hydroxycholecalciferol and calcium and higher mean serum B-ALP levels than the controls, respectively. The mean serum 25-hydroxycholecalciferol was significantly lower in children on AED polytherapy. There was negative correlation between the duration of drug therapy and all serum biochemical indices but this was only significant for serum 25-hydroxycholecalciferol level (p = 0.027). Age significantly impacted negatively on serum 25-hydroxycholecalciferol, p = 0.036 and calcium levels, p = 0.009, but not on B-ALP (p = 0.392).

Conclusion: Children on antiepileptic drugs in UPTH had lower mean serum 25-hydroxycholecalciferol and calcium levels but higher mean serum BALP level than healthy controls, as well as inverse relationship between duration of AED therapy and 25, hydroxycholecalciferol, calcium and B-ALP. We therefore recommend children with epilepsy on antiepileptic drugs have their serum 25-hydroxycholecalciferol, calcium and B-ALP levels monitored to enable early detection of any abnormalities.