RESUMO
OBJECTIVE: The aim of this study was to evaluate the effects of the classic ketogenic diet (KD) on low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subfractions in children and adolescents with refractory epilepsy. METHODS: This prospective study recruited children and adolescents of either sex, whose epilepsy was refractory to treatment with multiple drugs. To be included, the patient had to have an indication for treatment with the KD and be treated as an outpatient. At baseline and after 3 and 6 mo of the KD, lipid profile (total cholesterol [TC], triacylglycerols [TG], LDL cholesterol [LDL-C], and HDL cholesterol [HDL-C]), apolipoproteins (apoA-I and apoB), 10 subfractions of HDL, 7 subfractions of LDL, LDL phenotype, and LDL size were analyzed using the Lipoprint system. RESULTS: The lipid profile components (TC, TG, LDL-C, HDL-C, apoA-I, and apoB) increased during the 3-mo follow-up, and remained consistent after 6 mo of treatment. Similarly, non-HDL-C, TC/HDL-C, LDL-C/HDL-C, and apoB/apoA-I ratios, representing atherogenic particles, significantly increased. In contrast, qualitative lipoprotein characteristics progressively changed during the follow-up period. Small LDL subfractions increased, and this profile was related with reduced LDL size (27.3 nm to 26.7 nm). The LDL phenotype became worse; 52.1% of the patients had a non-A phenotype after 6 mo of the KD. Small HDL subfractions decreased only after 6 mo of the KD. CONCLUSIONS: KD treatment promotes negative changes in lipoprotein size and phenotype, contributing to atherogenic risk in these patients.