title: Changes in utilisation of antiepileptic drugs in epilepsy and non-epilepsy disorders-a pharmacoepidemiological study and clinical implications.
abstract: OBJECTIVE
  The purpose of this study was to investigate changes in utilisation of antiepileptic drugs (AEDs) in epilepsy and non-epilepsy disorders in Norway and furthermore to study the retention rates of the most commonly used AEDs in these indications in long-term use.
  
  
  METHODS
  The data consisted of all prescriptions of AEDs from Norwegian pharmacies in the Norwegian Prescription Database (NorPD) (2004-2012). Variables included anonymous data regarding age, gender, diagnosis specific reimbursement codes and utilisation of AEDs.
  
  
  RESULTS
  In recent years (2008-2012), the utilisation of AEDs in non-epilepsy disorders accounted for 45-53 % of the total use. In epilepsy, the most commonly used AED was lamotrigine, followed by levetiracetam, carbamazepine and valproate. Lamotrigine was also the predominant AED used in psychiatry, while pregabalin and gabapentin were mostly used in neuropathic pain. In migraine, topiramate predominated but accounted for <1 % of the total utilisation of AEDs. The majority of prescriptions were by general practitioners and only 20 % by specialists. Regardless of indication, newer AEDs had higher retention rates (34-48 %) and were used for a longer period before discontinuation.
  
  
  CONCLUSIONS
  The use of AEDs in non-epilepsy disorders is increasing and accounted for 53 % in 2012. Newer AEDs were predominantly used and demonstrated higher retention rates than older AEDs in all indications. This nationwide study demonstrates an increased exposure to AEDs in new patient groups, and details in prescription patterns and clinical and safety considerations should be closely monitored. This contributes to long-term post-marketing data of AED and accordingly improved pharmacovigilance.
authors.affiliation: Programme for Pharmacy, Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Arton
authors.initials: A
authors.lastname: Baftiu
authors.affiliation: Programme for Pharmacy, Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway. cecilie.landmark@hioa.no.|The National Center for Epilepsy, Sandvika, Oslo University Hospital, Oslo, Norway. cecilie.landmark@hioa.no.|Department of Pharmacology, Oslo University Hospital, Oslo, Norway. cecilie.landmark@hioa.no.
authors.forename: Cecilie
authors.initials: C
authors.lastname: Johannessen Landmark
authors.affiliation: Programme for Pharmacy, Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Ida Rudberg
authors.initials: IR
authors.lastname: Rusten
authors.affiliation: Programme for Pharmacy, Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Silje Andrea
authors.initials: SA
authors.lastname: Feet
authors.affiliation: The National Center for Epilepsy, Sandvika, Oslo University Hospital, Oslo, Norway.|Department of Pharmacology, Oslo University Hospital, Oslo, Norway.
authors.forename: Svein I
authors.initials: SI
authors.lastname: Johannessen
authors.affiliation: Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.
authors.forename: Pål G
authors.initials: PG
authors.lastname: Larsson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000927:Anticonvulsants / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004363:Drug Utilization / Q000706:statistics & numerical data*; D004827:Epilepsy / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D055118:Medication Adherence; D001523:Mental Disorders / Q000188:drug therapy; D008875:Middle Aged; D008881:Migraine Disorders / Q000188:drug therapy*; D009437:Neuralgia / Q000188:drug therapy*; D009664:Norway; D017891:Pharmacoepidemiology; D010818:Practice Patterns, Physicians'; D055815:Young Adult
chemical_list: D000927:Anticonvulsants
keywords: Antiepileptic drugs; Epilepsy; Non-epilepsy indications; Norwegian Prescription Database (NorPD); Pharmacoepidemiology; Pharmacovigilance; Retention rates