Risk factors for valproic acid resistance in childhood absence epilepsy.

Abstract

AIMS:

Valproic acid (VPA) is reported to be effective for the control of absence seizures in 75% of children. The aim of this study was to determine the clinical and socio-demographic factors associated with VPA response in newly diagnosed childhood absence epilepsy (CAE) and to determine if these factors also influence the chances of achieving long-term seizure freedom.

METHODS:

Medical charts of 180 children with CAE were retrospectively reviewed. Clinical, electroencephalographic and imaging findings were recorded to correlate with complete VPA response and long-term epilepsy outcome. Factors associated with non-responsiveness were identified individually and in a multivariable logistic regression analysis.

RESULTS:

Treatment was successful in 112 (58.3%) children. More children that were non-responsive to VPA experienced generalized tonic clonic seizures (GTCS) (33.8% vs. 13.4% for responders; p=0.001) and 52.9% had a pre-treatment seizure frequency greater than 10/day (vs. 27.0% for responders; p<0.001). Finally, responders were older at time of diagnosis versus non-responders (p=0.001). Absence of long-term seizure freedom was linked to the presence of GTCS, the absence of initial response and the need for multiple AEDs to control seizures.

INTERPRETATION:

Our results suggest that clinical phenotypes are associated with reduced response rates to VPA. This should be taken into account when counselling families of children with newly diagnosed absence epilepsy.

• Authors: May Lissa Ollivier, Marie France Dubois, Maja Krajinovic, Patrick Cossette, Lionel Carmant
• Journal: Seizure (Seizure) Vol. 18 Issue 10 Pg. 690-4 (Dec 2009) ISSN: 1532-2688 [Electronic] England
• PMID: 19836978 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anticonvulsants
• Valproic Acid

Topics

• Adolescent
• Age of Onset
• Anticonvulsants (adverse effects, therapeutic use)
• Child
• Child, Preschool
• Electroencephalography
• Epilepsy, Absence (chemically induced, drug therapy)
• Female
• Humans
• Infant
• Longitudinal Studies
• Male
• Predictive Value of Tests
• Risk Factors
• Treatment Outcome
• Valproic Acid (adverse effects, therapeutic use)