title: The impact of Medicare Part D on medication treatment of hypertension.
abstract: OBJECTIVE
  To evaluate Medicare Part D's impact on use of antihypertensive medications among seniors with hypertension.
  
  
  METHODS
  Medicare-Advantage plan pharmacy data from January 1, 2004 to December 12, 2007 from three groups who before enrolling in Part D had no or limited drug benefits, and a comparison group with stable employer-based coverage.
  
  
  METHODS
  Pre-post intervention with a comparison group design was used to study likelihood of use, daily counts, and substitutions between angiotensin-converting enzyme inhibitors and angiotensin-II receptor blockers (ARBs).
  
  
  RESULTS
  Antihypertensive use increased most among those without prior drug coverage: likelihood of use increased (odds ratio = 1.40, 95 percent confidence interval [CI] 1.25-1.56), and daily counts increased 0.29 (95 percent CI 0.24-0.33). Proportion using ARBs increased from 40 to 46 percent.
  
  
  CONCLUSIONS
  Part D was associated with increased antihypertensive use and use of ARBs over less expensive alternatives.
authors.affiliation: Department of Health Policy and Management, University of Pittsburgh, 130 De Soto Street, Crabtree Hall A664, Pittsburgh, PA 15261, USA. ytzhang@pitt.edu
authors.forename: Yuting
authors.initials: Y
authors.lastname: Zhang
authors.forename: Julie M
authors.initials: JM
authors.lastname: Donohue
authors.forename: Judith R
authors.initials: JR
authors.lastname: Lave
authors.forename: Walid F
authors.initials: WF
authors.lastname: Gellad
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D047228:Angiotensin II Type 1 Receptor Blockers / Q000191:economics / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000191:economics / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000191:economics / Q000627:therapeutic use*; D004363:Drug Utilization; D005260:Female; D006296:Health Services / Q000706:statistics & numerical data; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D054524:Medicare Part D / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D014481:United States
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents