The Study
Özdemir et al. (2015) studied the effects of a one-year ketogenic diet (KD), including the ones related to the serum lipid levels and to the structure and functions of the vascular system, in children suffering from epilepsy that do not respond to the standard pharmacological treatments. It is interesting to note that the actual effects of the KD on the vascular system are controversial and it is thought that KD could lead to dyslipidemia, which is an abnormal amount of blood lipids, a known risk factor of developing atherosclerosis, consisting in a thickening of the artery wall.

Methods
Sixty-five children suffering from different forms of epilepsy refractory to pharmacological treatments and aged between 12 months and 18 years were enrolled in this study. Patients suffering from another disease affecting the cardiovascular system were excluded from this study. Enrolled patients followed a complex protocol of KD consisting of a ratio fat to carbohydrates of 3:1 plus protein constantly adjusted until the blood ketone levels was stable around 4-5 mmol/L. The daily caloric intake was also adjusted according to the weight, the height, the ideal body weight and the physical activity level of each child. The main source of polyunsaturated fat used in this study was olive oil. This KD protocol was observed for one year and follow-up exams were performed at baseline and after 1, 3, 6 and 12 months of the KD protocol.

Results
Fifty-two patients followed the KD protocol for the entire one-year period and were then included in the study, implying that thirteen patients discontinued the KD before the end of the one-year period. Among them, six presented a lack of seizure control, four presented a gastrointestinal intolerance to the KD and three presented a lack of compliance to the KD protocol.

On average, patients that completed the study were taking three antiepileptic drugs at the beginning of the study and only one at the end of the one-year KD protocol. Furthermore, 21 patients at the third month and 25 patients after one year did not have seizure anymore. Another three patients at the sixth month and five patients after one year had a reduction of more than 90 % of their seizure frequency. At the end of the one-year KD protocol, serum levels of total cholesterol, of LDL-cholesterol (the so-called “bad” cholesterol), and triglycerides were significantly increased compared to the baseline, while the serum levels of HDL-cholesterol (the so-called “good” cholesterol) remain unchanged. However, all the assessed parameters involved in the structure of the vascular system were not changed after the one-year KD protocol.

Conclusion
The one-year KD protocol used in this study had beneficial effects on the seizure frequency in more than half of all the enrolled children suffering from pharmacological treatment-resistant epilepsy, although the KD has been associated with an increase of lipid serum levels in these patients.

In this study, the authors state that “we observed no statistically significant detrimental effects of a 12-month long KD on cIMT (carotid intima-media thickness), the elastic properties of the aorta and the carotid artery in epileptic children, despite increased concentrations of serum lipids.

The authors suggest that the use of olive oil, a lipid source known for its cardioprotective effects, might be the main reason explaining the absence of adverse effects on the structure of the vascular system in the enrolled children.

Study Editor

Marie-Christine Brotherton holds a Ph.D. in Cellular and Molecular Biology with specific expertise in Parasitology, Proteomics, Drug Resistance and Genomics. She also holds a MBA with a major in Corporate Social and Environmental Responsibility. She has strong experience with the scientific publication process, including author guidelines requirements, as well as with the medical and social/environmental fields. She can be reached by email at marie-christine.brotherton.1@ulaval.ca

Citation

Özdemir, R., Güzel, O., Küçük, M., Karadeniz, C., Katipoglu, N., Yılmaz, Ü., … & Meşe, T. (2015). The Effect of the Ketogenic Diet on the Vascular Structure and Functions in Children With Intractable Epilepsy. Pediatric Neurology, 56, 30-34.