Effect of oxcarbazepine on bone mineral density and biochemical markers of bone metabolism in patients with epilepsy

Purpose: Antiepileptic drugs (AEDs) may cause adverse effects on bone metabolism and bone mineral density (BMD). The aim of this study is to determine the effect of oxcarbazepine (OXC) monotherapy on biochemical markers of bone metabolism and BMD in epilepsy patients. Methods: Forty-one new onset drug naïve epilepsy patients were recruited (19 females, 22 males; mean age: 28.2. ±. 8.4 years). We measured biochemical markers of bone metabolism (serum calcium, phosphate, bone alkaline phosphatase, parathyroid hormone, osteocalcin, insulin-like growth factor (IGF)-1, C-telopeptide, Vitamin D3 levels) and BMD by DEXA (dual energy X-ray absorptiometry) method in all patients before and after a long-term OXC monotherapy. Results: Most of biochemical markers were not changed significantly, but serum calcium (p= 0.0087) and bone specific ALP was reduced (p= 0.0499) significantly after OXC monotherapy in epilepsy patients. BMD at the lumbar spine (L2 to L4) was significantly increased after OXC monotherapy (p= 0.0001), revealed by repeated measures ANOVA with Bonferroni's correction of confounders including sex, age, average dose, and treatment duration. However, BMD at the lumbar spine (L2 to L4) was significantly increased (p= 0.012) only in female patients in each gender analysis. Conclusions: This study demonstrates that a long-term OXC monotherapy does not appear to have harmful effect on bone health in drug naïve epilepsy patients.