title: Impact of drug plans on adherence to and the cost of antihypertensive medications among patients covered by a universal drug insurance program.
abstract: BACKGROUND
  This study aimed to assess the impact of the type of drug plan on adherence to antihypertensive medication treatment as well as the cost of these medications within universal drug insurance programs.
  
  
  METHODS
  To compare adherence to antihypertensive medication treatment and the cost of antihypertensive medications between adults with public and private drug insurance in the province of Québec, Canada, we reconstructed a matched retrospective cohort by linking data recorded in 3 administrative databases between March 2008 and May 2010. The cohort included 186 privately and 1747 publicly insured patients aged 18-64 years who were treated with 1 or 2 antihypertensive medications. Adherence measured with the proportion of days covered (PDC) over 1 year and the cost of antihypertensive medications were evaluated for new and prevalent users separately.
  
  
  RESULTS
  More than 70% of patients were 50-64 years old and 90% of the publicly and 72% of the privately insured patients were using only 1 antihypertensive medication. The mean PDC among new users of 1 antihypertensive medication was 58.8% for privately insured patients and 65.0% for publicly insured patients, but the difference was not statistically significant. However, privately insured patients treated with 2 antihypertensive medications were more likely to be adherent (PDC-P, 15.0%; 95% confidence interval, 7.0-24.0). Privately insured patients (CAD$41.52) had to pay significantly more for their antihypertensive medications than did publicly insured patients (CAD$32.21).
  
  
  CONCLUSIONS
  The cost of antihypertensive medications was higher for patients with private drug insurance, although adherence was similar in both groups. The results may reflect regulation of dispensing fees for publicly insured patients.
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada.
authors.forename: François
authors.initials: F
authors.lastname: Després
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Perreault
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada.
authors.forename: Lyne
authors.initials: L
authors.lastname: Lalonde
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, Québec, Canada.
authors.forename: Amélie
authors.initials: A
authors.lastname: Forget
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, Québec, Canada.
authors.forename: Fatima-Zohra
authors.initials: FZ
authors.lastname: Kettani
authors.affiliation: Faculty of Pharmacy, Université de Montréal, Montreal, Québec, Canada; Research Center, Hôpital du Sacré-Coeur de Montréal, Montreal, Québec, Canada; Endowment Pharmaceutical Chair, AstraZeneca in Respiratory Health, Montreal, Québec, Canada. Electronic address: lucie.blais@umontreal.ca.
authors.forename: Lucie
authors.initials: L
authors.lastname: Blais
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000191:economics* / Q000627:therapeutic use; D016208:Databases, Factual; D016527:Drug Costs; D011307:Drug Prescriptions / Q000191:economics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000191:economics; D007356:Insurance, Pharmaceutical Services / Q000191:economics*; D008297:Male; D008875:Middle Aged; D009313:National Health Programs; D011792:Quebec; D012051:Reimbursement Mechanisms / Q000191:economics*; D012189:Retrospective Studies; D016903:Drug Monitoring
chemical_list: D000959:Antihypertensive Agents