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When do seizures usually improve with the ketogenic diet?
Eric H Kossoff1, Linda C Laux, Robyn Blackford
1Department of Neurology, The Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA. ekossoff@jhmi.edu
Insights
The ketogenic diet (KD) often improves seizures within 1-2 weeks for children. If no seizure reduction occurs after 2 months, discontinuing the KD may be considered. Fasting at onset may speed initial results.
Area of Science:
- Pediatric Neurology
- Dietary Therapies
Background:
- Parents anticipate rapid seizure control with the ketogenic diet (KD) in children.
- Understanding the timeline for KD effectiveness is crucial for managing expectations and treatment duration.
Purpose of the Study:
- To determine the typical time to seizure reduction in children starting the KD.
- To establish a timeframe beyond which the KD is unlikely to be effective.
Main Methods:
- Retrospective review of 118 children initiated on the KD at two major hospitals.
- Data collection focused on the date of documented seizure improvement.
Main Results:
- 84% of children experienced seizure reduction, with a median time to improvement of 5 days.
- 75% of children showed improvement within 14 days.
- Fasting prior to KD initiation correlated with quicker initial seizure reduction (median 5 vs. 14 days).
Conclusions:
- The ketogenic diet, when effective, typically shows results within 1-2 weeks.
- Fasting may accelerate initial seizure reduction but does not alter long-term outcomes.
- Discontinuation of the KD can be considered if no seizure reduction is observed within 2 months.
Purpose:
Parents often expect immediate seizure improvement after starting the ketogenic diet (KD) for their children. The purpose of this study was to determine the typical time to seizure reduction as well as the time after which it was unlikely to be helpful in those children started on the KD.
Methods:
Records of all children started on the KD at Johns Hopkins Hospital, Baltimore (n = 83) and Children's Memorial Hospital, Chicago (n = 35) from November 2003 to December 2006 were examined to determine the first day in which seizures were reportedly improved.
Results:
Of the 118 children started on the KD, 99 (84%) had documented seizure reduction. The overall median time to first improvement was 5 days (range: 1-65 days). Seventy-five percent of children improved within 14 days. In those children who were fasted at KD onset, the time to improvement was quicker (median 5 vs. 14 days, p < 0.01) with a higher percentage improving within 5 days (60% vs. 31%, p = 0.01). No difference was identified between fasting and nonfasting in regards to long-term outcomes, however.
Discussion:
The KD works quickly when effective, typically within the first 1-2 weeks. Starting the KD after a fasting period may lead to a more rapid, but equivalent long-term seizure reduction, confirming prior reports. If the KD has not led to seizure reduction after 2 months, it can probably be discontinued.
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