Topiramate in children with west syndrome: a retrospective multicenter evaluation of 100 patients

The aim of this study is to investigate the efficacy and tolerability of topiramate in a large number of children with West syndrome. The authors performed a retrospective, questionnaire-based data collection in specialized epilepsy units in Germany. Patients with West syndrome and hypsarrhythmia could be included if topiramate treatment had started at an age of < or =3 years. Data of 100 patients were evaluated. Nearly all patients were severely affected and had been treated with multiple antiepileptic drugs with insufficient effect. Topiramate was introduced at a median age of 11.9 months. The median starting dosage was 1.6 mg/kg body weight per day, increased to a median maximum dosage of 12.0 mg/kg. Sixty-one patients received between 1 and 3 antiepileptic drugs in addition to topiramate. The median daily dose considered by the attending physicians to be most effective regarding seizure reduction was 10 mg/kg. A significant reduction in the number of seizures per week was achieved. A total of 17.5% of patients became free of seizures, and in 47%, the seizure frequency decreased by at least 50%. Hypsarrhythmia or status-like electroencephalography patterns remitted in 18 of 83 cases. Side effects were reported in 25% of children and included mostly sedation, loss of appetite, weight loss, and metabolic acidosis. These side effects were statistically related to the number of additional antiepileptic drugs but not to the topiramate dosage. In 17% of patients, topiramate treatment was discontinued because of side effects and in a further 4% because of worsening of seizures. In 44% of patients, treatment was continued for more than 3 months. In conclusion, the data suggest that topiramate is a useful drug in treating West syndrome. However, because of the inherent limitations of the retrospective study design, future prospective controlled studies should be performed.