title: Risk of seizure recurrence after achieving initial seizure freedom on the ketogenic diet.
abstract: OBJECTIVE
  Few studies have examined the long-term sustainability of complete seizure freedom on the ketogenic diet (KD). The purpose of this study was to describe the risk of seizure recurrence in children who achieved at least 1 month of seizure freedom on the KD, and to assess clinical features associated with sustained seizure freedom.
  
  
  METHODS
  Records of patients initiated on the KD at The Children's Hospital of Philadelphia (CHOP) from 1991 to 2009 were reviewed. Subjects who attained seizure freedom for at least 1 month within 2 years were included in the study. Seizure frequency was recorded based on caregiver-reported seizure diaries as unchanged, improved, or worse compared to baseline. Those patients with seizure freedom ≥1 year were compared to those with seizure freedom <1 year in terms of demographics, age of seizure onset, number of antiepileptic drugs (AEDs) prior to KD, and epilepsy classification.
  
  
  RESULTS
  Of 276 patients initiated on the KD, 65 patients (24%) attained seizure freedom for a minimum of 1 month. The majority of these patients had daily seizures. The median time to seizure freedom after KD initiation was 1.5 months. Seizures recurred in 53 patients (82%), with a median time to seizure recurrence of 3 months. However, seizure frequency after initial recurrence remained far less than baseline. No clinical features were identified as risk factors for seizure recurrence.
  
  
  CONCLUSIONS
  Seizure recurrence on the KD after 1 month of seizure freedom most often occurred as occasional breakthrough seizures and not a return to baseline seizure frequency. This study provides evidence to support the continued use of the KD in patients with initial seizure freedom even after breakthrough seizures. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.
authors.affiliation: Division of Neurology, Departments of Pediatrics and Neurology, The Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A.
authors.forename: Katherine S
authors.initials: KS
authors.lastname: Taub
authors.forename: Sudha Kilaru
authors.initials: SK
authors.lastname: Kessler
authors.forename: A G Christina
authors.initials: AG
authors.lastname: Bergqvist
mesh_terms: D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D055423:Diet, Ketogenic / Q000379:methods* / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D055502:Secondary Prevention; D012640:Seizures / Q000175:diagnosis* / Q000178:diet therapy* / Q000503:physiopathology
keywords: Children; Ketogenic diet; Medication-resistant epilepsy; Seizure freedom