title: A retrospective evaluation of retigabine in patients with cognitive impairment with highly drug-resistant epilepsy.
abstract: OBJECTIVE
  The purpose of this study was to evaluate retrospectively the efficacy and tolerability of retigabine (RTG) in residential patients of an epilepsy center.
  
  
  METHODS
  We used an industry-independent noninterventional retrospective evaluation on the basis of paper and electronic records plus interrogation of the treating neurologists. All patients (N=20; 7 females; mean age: 31.8, range: 18-54years) started on RTG between May 2011 and March 2012 were included. Evaluation was carried out after 6, 12, and 24months. Changes in seizure frequency were measured as the number of seizures during three months on RTG compared with a three-month baseline period. The Clinical Global Impression scale was applied to include qualitative changes in seizure severity. All but one patient had symptomatic (structural; one patient: metabolic) or cryptogenic focal or multifocal epilepsy. All had grade III drug-resistant epilepsy and cognitive deficits of different degrees.
  
  
  RESULTS
  The retention rates were 60% after 6months, 35% after 12months, and 20% after 24months. At 12months, there were 2 responders (10%): one had a >90% seizure reduction and the other had a >50% seizure reduction. Another 5 patients were still on RTG because of minor improvements. The reasons for discontinuation in 13 patients were adverse effects (6), lack of effect (6), and both (1). Cognitive or emotional changes were the side effects that most frequently led to discontinuation. Beyond the 12-month evaluation, 3 patients were discontinued as a consequence of the FDA warning regarding retinal pigmentation and discoloration of skin and nails in patients exposed to RTG. One patient had a moderate blue-gray finger coloring. Ophthalmological changes were not discovered.
  
  
  CONCLUSIONS
  Retigabine proved to be useful only for a small minority of patients in a sample of patients with particularly difficult-to-treat epilepsy.
authors.affiliation: Von Bodelschwinghsche Stiftungen Bethel, Bethel.regional, Ebenezerweg 18, 33617 Bielefeld, Germany. Electronic address: Bernd.Huber@Bethel.de.
authors.forename: Bernd
authors.initials: B
authors.lastname: Huber
authors.affiliation: Von Bodelschwinghsche Stiftungen Bethel, Bethel.regional, Ebenezerweg 18, 33617 Bielefeld, Germany. Electronic address: Michelina.Bocchicchio@Bethel.de.
authors.forename: Michelina
authors.initials: M
authors.lastname: Bocchicchio
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use*; D002219:Carbamates / Q000627:therapeutic use*; D003071:Cognition; D003072:Cognition Disorders / Q000150:complications*; D015331:Cohort Studies; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000150:complications*; D008297:Male; D008875:Middle Aged; D010655:Phenylenediamines / Q000627:therapeutic use*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D002219:Carbamates; D010655:Phenylenediamines; C101866:ezogabine
keywords: Cognitive deficit; Drug-resistant epilepsy; Partial epilepsy; Retigabine; Side effect