title: Refill Adherence in Relation to Substitution and the Use of Multiple Medications: A Nationwide Population Based Study on New ACE-Inhibitor Users.
abstract: Generic substitution has contributed to economic savings but switching products may affect patient adherence, particularly among those using multiple medications. The aim was to analyse if use of multiple medications influenced the association between switching products and refill adherence to angiotensin-converting-enzyme (ACE) inhibitors in Sweden.
  
  
  
  New users of ACE-inhibitors, starting between 1 July 2006 and 30 June 2007, were identified in the Swedish Prescribed Drug Register. Refill adherence was assessed using the continuous measure of medication acquisition (CMA) and analysed with linear regression and analysis of covariance.
  
  
  
  The study population included 42735 individuals whereof 51.2% were exposed to switching ACE-inhibitor and 39.6% used multiple medications. Refill adherence was higher among those exposed to switching products than those not, but did not vary depending on the use of multiple medications or among those not. Refill adherence varied with age, educational level, household income, country of birth, previous hospitalisation and previous cardiovascular diagnosis.
  
  
  
  The results indicate a positive association between refill adherence and switching products, mainly due to generic substitution, among new users of ACE-inhibitors in Sweden. This association was independent of use of multiple medications.
authors.affiliation: Nordic School of Public Health, Gothenburg, Sweden.|Unit for Social Epidemiology, Clinical Research Centre, Faculty of Medicine, Lund University, Lund, Sweden.
authors.forename: Pernilla J
authors.identifier: 0000-0003-4616-9525
authors.initials: PJ
authors.lastname: Bjerkeli
authors.affiliation: Department of Forensic Genetics and Forensic Toxicology, National Board Forensic Medicine, Linköping, Sweden.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Jönsson
authors.affiliation: Nordic Health Economics AB, Gothenburg, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Lesén
authors.affiliation: Research and Development, Sahlgrenska University Hospital, Gothenburg, Sweden.|Section for Epidemiology and Social Medicine, Department of Public Health and Community Medicine at Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Ann-Charlotte
authors.initials: AC
authors.lastname: Mårdby
authors.affiliation: Section for Epidemiology and Social Medicine, Department of Public Health and Community Medicine at Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Karolina Andersson
authors.initials: KA
authors.lastname: Sundell
mesh_terms: D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000188:drug therapy / Q000453:epidemiology; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D057915:Drug Substitution / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D013548:Sweden / Q000453:epidemiology; D016903:Drug Monitoring
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors