Abstracts

Rationale: High-fat diets have historically been found to produce significant increases in the atherogenic apoB containing lipoproteins and a decrease in the antiatherogenic HDL cholesterol. The ketogenic diet (KD) may contain a total of 71% - >90% of calories derived from fat. There are no long-term studies that address the effect of the KD on children with hyperlipidemia prior to treatment. The objective of this study is to assess the change in lipid status of children who had hyperlipidemia prior to starting either the classic KD or medium-chain triglyceride (MCT) KD over a 12 month period.Methods: Twelve children, age 0.6-8 years (mean SD=3.5 2.9), were treated with a KD from 9/2000 to 5/2011. Fasting serum lipid levels including total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), high-density lipoprotein (HDL), total cholesterol/HDL (TC/HDL) were measured prior to diet commencement and at 3, 6 and 12 months after diet initiation. The following laboratory reference ranges were used: TC: 3.2-4.4 mmol/L; LDL: 0.98-3.62 mmol/L; TG: 0.4-1.30 mmol/L; HDL: 0.6-1.81 mmol/L; healthy levels of TC/HDL: <4.11. Paired t-tests were performed to compare lipid levels and TC/HDL ratio of children treated with the KD at diet initiation, with levels at 3, 6 and 12 months of dietary treatment. Results: Prior to diet initiation, the mean lipid levels were: TC: mean SD=5.5 0.9, LDL: mean SD=3.3 1, TG: mean SD=1.7 1.8, HDL: mean SD=1.5 0.5 and TC/HDL: mean SD=4.1 1.6. After treatment with the KD, the mean lipid levels at 3, 6 and 12 months respectively for each parameter were: TC: mean SD=4.4 0.5; 4.3 0.8; 3.7 0.9; LDL: mean SD=2.3 0.5; 2.5 1; 1.9 0.7; TG: mean SD=1.9 1.7; 1.3 0.8; 0.9 0.2; and TC/HDL: mean SD=4.1 1.7; 4.7 3.4; 3.1 1.2. These results revealed a decreasing trend for lipid parameters. The HDL remained the same with mean SD=1.3 0.5; 1.2 0.5; 1.3 0.5. Paired t-tests were used to compare lipid and TC/HDL ratio levels from prior to diet treatment with the levels at 3, 6 and 12 months. A significant decrease was seen in TC levels between pre-diet and at 3 (p<0.01), 6 (p<0.05) and 12 months (p<0.01). The LDL levels decreased significantly between baseline and 3 (p<0.01) and 12 months (p<0.01). There was no significant difference between baseline LDL levels and at 6 months. For the TC/HDL, there was significant decrease between baseline and at 12 months (p<0.01). The KD had no significant effect on HDL and TG levels at 3, 6 or 12 months. Conclusions: In this cohort of children with hyperlipidemia prior to starting the KD, TC and LDL decreased to within normal reference ranges while treated with the KD. There was also a decrease in the TC/HDL ratio and no significant decrease in HDL. The dietitians monitored lipid levels closely and increased the intake of poly and monounsaturated fats while decreasing transfat, saturated fat and cholesterol in order to achieve healthy lipid levels. Further studies are needed in order to determine longer-term outcomes in a larger population of patients.