Abstract
OBJECTIVE: The aim of the study was to compare the prevalence of metabolic syndrome (MS) and its components in patients treated with valproic acid (VPA) to the general population. BACKGROUND: There are no studies that explored the prevalence of MS in people with epilepsy treated with VPA at the population based level. DESIGN/METHODS: Using drug prescription database, 118 (63 male and 55 female) adult patients with epilepsy receiving VPA monotherapy for at least 3 months were included in the study to evaluate the presence of MS. All patients were interviewed and clinically examined, blood samples were obtained after an overnight fast. Insulin resistance was estimated using the homeostasis model assessment (HOMA-IR). MS was diagnosed according to National Cholesterol Education Programm Adult Treatment Panel III criteria. Data was compared to the results of a population-based study on the prevalence of metabolic disorders conducted in the same geographical region earlier. RESULTS: The prevalence of MS in patients on VPA monotherapy was 25.8%, which was similar to the prevalence of MS in control group (27.9%). Multiple logistic regressioon analysis showed a positive correlation between the developement of MS and body mass index (BMI), OR=1.47 (95% CI 1.25-1.73) and VPA medication duration, OR=1.01 (95% CI 1.0-1.02). However, there was no correlation between developement of MS, VPA dosage and HOMA-IR. Comparison of BMI and HOMA-IR as markers for MS in both cohorts indicated, that in the control subjects both parameters similarly predicted the occurence of MS. However, in the VPA-treated patients the predictive ability of HOMA-IR comparing to the BMI was significantly lower, with the areas under the receiver operating characteristic curves 0.808 and 0.897 (P=0.05), respectively. CONCLUSIONS: The prevalence of MS in patients with epilepsy on VPA treatment is not more common than in the general population. HOMA-IR is not so good predictor of MS in patients receiving VPA treatment as in general population.