title: Increased mortality persists in an adult drug-resistant epilepsy prevalence cohort.
abstract: OBJECTIVE
  To investigate the cumulative probability of death and the standardised mortality ratio (SMR) in an adult drug-resistant epilepsy (DRE) population.
  
  
  METHODS
  In two separate centres during 2003-2006, we identified a total of 433 patients with DRE defined as at least one seizure per month and failure of at least two antiepileptic drugs. These patients were subsequently followed for a total follow-up of 6 years. We examined the cumulative probability of death, using Kaplan-Meier methodology, and the SMR based on mortality data from the Social Security Death Index. Clinical predictors of death were evaluated using Cox regression analysis.
  
  
  RESULTS
  The cumulative probability of death was 8.7% (95% CI 6.2% to 12.1%) at 6 years. The overall SMR was 2.4 (95% CI 1.7 to 3.3). It was 3.1; 95% CI 2.0 to 4.6 in subjects with remote or progressive aetiology and 1.7; 95% CI 0.8 to 2.8 in subjects with unknown aetiology. The SMR was significantly increased in those with a known remote aetiology (2.5; 95% CI (1.4 to 3.8)). Older age at enrolment and symptomatic generalised epilepsy syndrome were significant predictors of death.
  
  
  CONCLUSIONS
  Mortality is increased in this drug-resistant population; largely driven by those with a known epilepsy aetiology. The increased mortality remains even after exclusion of those with a progressive aetiology. Previous studies of incident epilepsy cohorts revealed increased mortality that declines to near-normal levels after the first several years, but in our DRE cohort, mortality remains elevated despite a median duration of epilepsy of 25 years at study entry.
authors.affiliation: Department of Neurology, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Callaghan
authors.affiliation: Columbia University, New York, New York, USA.
authors.forename: Hyunmi
authors.initials: H
authors.lastname: Choi
authors.affiliation: Columbia University, New York, New York, USA.
authors.forename: Malka
authors.initials: M
authors.lastname: Schlesinger
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: William
authors.initials: W
authors.lastname: Rodemer
authors.affiliation: Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: John
authors.initials: J
authors.lastname: Pollard
authors.affiliation: Columbia University, New York, New York, USA.
authors.forename: Dale C
authors.initials: DC
authors.lastname: Hesdorffer
authors.affiliation: Columbia University, New York, New York, USA.
authors.forename: W Allen
authors.initials: WA
authors.lastname: Hauser
authors.affiliation: New York University, New York, New York, USA.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: French
mesh_terms: D000328:Adult; D000367:Age Factors; D002423:Cause of Death; D015331:Cohort Studies; D004351:Drug Resistance; D004827:Epilepsy / Q000209:etiology / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015995:Prevalence
keywords: Anticonvulsants; Epilepsy; Neuroepidemiology