Abstracts

Rationale: In this retrospective Cohort-study, the aim was to evaluate the prevalence and risk factors of vitamin D deficiency and the changes of vitamin D level among children with epilepsy on antiepileptic drugs (AEDs) treated in South Korea. Methods: In the children with epilepsy taking AEDs in a tertiary center, the levels of serum 25-hydroxy vitamin D (25-OHD) were measured at the start of AEDs and at 6-12 months intervals. Vitamin D deficiency was defined as 25-OHD levels <20 ng/mL, and insufficiency between 21 and 29 ng/mL. Potential risk factors were investigate as followings: sex, age, etiologies, seizure types, seizure outcomes, number of AEDs, ambulation, mental retardation, tubal feeding, and body mass index (BMI). Results: One-hundred and twenty children (88 boys, 32 girls) with mean age 7.48 5.20 years were included. Mean follow-up duration of 25-OHD was 1.73 0.80 years. At the start of AEDs and the last follow-up, Vitamin D deficiency or insufficiency was recognized in 56.7% (68 of 120) vs 78.3% (94 of 120), respectively (p=0.0003). The mean value of initial 25-OHD was 31.3 14.9 ng/mL, and of last checked 25-OHD significantly decreased to 20.1 14.5 ng/mL (p<0.0001). The mean value of difference between the initial and last follow-up 25-OHD (D-25-OHD) was -11.2 15.1 ng/mL. Non-ambulatory children (D-25-OHD; -17.7 11.9 ng/mL, p=0.0049), children on tubal feeding (D-25-OHD; -19.1 14.0 ng/mL, p=0.0197), under polytherpy (D-25-OHD; -16.0 14.1 ng/mL, p=0.0012), with uncontrolled seizures (D-25-OHD; -14.2 12.8 ng/mL, p=0.0233), and with elevated BMI (D-25-OHD; -17.8 12.5 ng/mL, p=0.0003) were at increased risk for more significantly decreased 25-OHD. Gender, age, mental retardation, etiologies and seizure types did not affect. Conclusions: High proportion of these children on AEDs had vitamin D deficiency or insufficiency, and significant difference between the initial and last follow-up 25-OHD. Non-ambulation, tubal feeding, polytherapy, uncontrolled seizures, and elevated BMI were significant risk factors for lower 25-OHD levels.