The ketogenic diet can be a very effective long-term treatment for children with epilepsy despite the potential adverse effects and challenges in following the diet, according to a study presented by Darcy Groesbeck at this year’s 58th annual meeting of the American Academy of Neurology, held in San Diego.

Groesbeck and her colleagues Renee Bluml, M.S., R.D., L.D., a nutritionist, and Eric Kossoff, M.D., a pediatric neurologist, all from Johns Hopkins Medical Institutions, Baltimore, M.D., reviewed the charts of 28 children (15 boys, 13 girls) who had remained on the ketogenic diet for 6-12 years for the treatment of epilepsy. Three children (11%) became seizure-free, seizures in another 21 were greater than 90% improved, and 4 had 50-90% improvement in seizure frequency. In addition, 9 were able to discontinue all antiepileptic drugs. Overall, medications decreased from an average of 2.1 to 1.3 per child.

“If you put kids on the diet, efficacy can be maintained for a long time” observed Groesbeck. She also noted that, “The diet may require a lot of tweaking in the early stages to make it work.”

Of the 28 children, 9 were maintained on a 4:1 ratio of fats to carbohydrates and proteins, while the remainder of the children followed a 3:1 or less restrictive regimen. Feedback from the parents revealed that 21 (91%) found the diet easy to maintain on a long-term basis.

Adverse Effects of the Ketogenic Diet"

Growth

Although the ketogenic diet is supposed to be calorie-adjusted to allow normal growth, significant adverse effects on growth were observed. At the onset of the diet 14/28 (50%) of the children were below the 10th percentile for weight, which increased to 23 (82%) children at the final follow-up visit (p=0.01). For height 10/28 (36%) of the children were below the 10th percentile when they started the diet, which increased significantly to 23 children at the final follow-up visit.

Kidney Stones

In addition, 7 of the children developed kidney stones. “Of the 7 children who developed kidney stones, only 1 was taking Polycitra-K (citric acid; potassium citrate) at that time. When it was started in the others, there were no recurrences of kidney stones”, Groesbeck said. Jeannie Burns, M.S., R.D., L.D., a pediatric and metabolic dietician at Rhode Island and Hasbro Children’s Hospitals, Providence, RI, commented, “Parents can buy home testing strips to test for blood in the urine, an early sign of kidney stones. Also, some facilities, such as Massachusetts General Hospital, Boston, MA, are not restricting fluids and still having success with the ketogenic diet.

Cholesterol

Cholesterol increased from a baseline of 178 mg/dl (112-268) to 201 mg/dl (94-383). HDL was 52 mg/dl (16-165) at baseline and 54 mg/dl (25-103) when last measured. LDL increased from 103 mg/dl (52-180) to 129 mg/dl (46-306). Triglycerides were 120 mg/dl (50-538) at baseline and decreased to 97 mg/dl (36-237). “Dyslipidemia (an alteration of fats in the blood) did not seem to occur overall in children on the ketogenic diet long-term,” said Groesbeck.

Bone Fractures

Although all of the children were prescribed calcium supplementation, 6 (21%) had bone fractures. “We haven’t routinely been getting bone (DEXA) scans,” acknowledged Groesbeck, “but we should consider long-term bone density monitoring.” David Mandelbaum, M.D., Ph.D., a pediatric neurologist at Brown Medical School, Providence, RI, also believes that “in order to reduce the risk of bone fractures, it is important to supplement with multivitamins, which should include vitamin D.”

Other Low-Carbohydrate Diets: Alternatives to Ketogenic Diet

“There is some interesting data on the Atkins diet type regimen and the South Beach diet type regimen showing efficacy in seizure reduction; both are much easier to administer than the ketogenic diet,” said Mandelbaum. “We have recently been implementing these types of diets as outpatients while waiting to admit the child to hospital to start the ketogenic diet with the idea that maybe a good response to the easier diet will not require a more rigorous diet. If the child doesn’t respond, then we initiate the traditional ketogenic diet.”

Jeannie Burns, MS, RD, LD, a pediatric and metabolic dietitian who works with Dr. Mandelbaum, added, “Another diet that is similar to the South Beach or Atkins Diet is the Low Glycemic Index Treatment Diet, which restricts carbohydrate, but not as much as the ketogenic diet and also involves use of foods with a low glycemic index to keep blood glucose constant.”

Groesbeck concluded, “Many parents are happy with the diet, even in the children who still have a few seizures. Parents should try the diet for at least 3 months before giving up.”

References

Groesbeck DK, Bluml RM, Kossoff EH. Long-term use of the ketogenic diet: Outcomes of 28 children with over 6 years diet duration. Neurology 2006;66(Suppl 2):A41