The Effect of Ketogenic Diet on Serum Selenium Levels in Patients with Intractable Epilepsy.

Abstract

The aim of the present study was to evaluate serum selenium levels in children receiving olive oil-based ketogenic diet (KD) for intractable seizures for at least 1year. Out of 320 patients who were initiated on KD, patients who continued receiving KD for at least 12months were enrolled. Sixteen patients who had selenium deficiency at the time of starting KD were excluded. Finally, a total of 110 patients (mean age 7.3±4.2years) were included. Serum selenium levels were measured at baseline and at 3, 6, and 12months after treatment initiation by using atomic absorption spectroscopy. Selenium deficiency was defined as a serum selenium level <48μg/L at each visit. Repeated measure ANOVA with post hoc Bonferroni correction was used for data analysis. Mean duration of KD was 15.3±4.3months. Mean serum selenium levels were significantly lower at 6 and 12months of KD treatment (66.2±23.3 and 57.2±16.2μg/L, respectively) compared to pre-treatment levels (79.3±25.7μg/L) (p=0.001). On the other hand, selenium levels did not show any significant difference at 3months of KD treatment (70.0±21.2μg/L) compared to baseline levels (p=0.076). A total of 54 patients (49.1%) were diagnosed with selenium deficiency, and oral selenium medication was initiated for these patients. No relevant clinical findings were detected, and echocardiographic findings were normal in all patients. The decline of the serum selenium concentrations after 6 and 12months of ketogenic diet suggests that patients on this highly prescriptive dietary treatment need close monitoring of this trace element.