title: VHA pharmacy use in veterans with Medicare drug coverage.
abstract: OBJECTIVE
  To determine how Medicare benefits affect veterans' use of Veterans Health Administration (VHA) pharmacy services.
  
  
  METHODS
  Retrospective analysis of veterans dually enrolled in the Veterans Health Administration and Medicare healthcare systems.
  
  
  METHODS
  We used VHA and Medicare administrative data for calendar year 2002 to examine the effect of Medicare HMO pharmacy benefit levels on VHA pharmacy use.
  
  
  RESULTS
  In 2002, 64% of the VHA and Medicare dually enrolled veterans in our study sample received medications from the VHA. Use of VHA pharmacy services varied monotonically by the level of pharmacy benefits among Medicare HMO enrollees, with veterans enrolled in plans with both low and high pharmacy benefit levels significantly less likely to use VHA pharmacy services than veterans in plans with no pharmacy benefits (odds ratios = .83 and .53, respectively, versus plans with no benefits). Among VHA pharmacy users, enrollment in plans with high levels of benefits was associated with significantly lower annual pharmacy costs than enrollment in plans with no benefits or enrollment in traditional Medicare.
  
  
  CONCLUSIONS
  Our findings indicate that non-VHA pharmacy benefits affect both the likelihood and magnitude of VHA pharmacy use. This suggests that Medicare pharmacy coverage (Part D) may significantly reduce the demand for VHA pharmacy services, particularly in geographic regions previously underserved by Medicare managed care plans.
authors.affiliation: Division of Management, Policy, and Community Health, University of Texas School of Public Health, Houston, TX, USA. robert.o.morgan@uth.tmc.edu.
authors.forename: Robert O
authors.initials: RO
authors.lastname: Morgan
authors.forename: Laura A
authors.initials: LA
authors.lastname: Petersen
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Hasche
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Davila
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Byrne
authors.forename: Nora I
authors.initials: NI
authors.lastname: Osemene
authors.forename: Iris I
authors.initials: II
authors.lastname: Wei
authors.forename: Michael L
authors.initials: ML
authors.lastname: Johnson
mesh_terms: D000368:Aged; D005260:Female; D006279:Health Maintenance Organizations; D006801:Humans; D008297:Male; D020398:Medicare Part C / Q000706:statistics & numerical data; D054524:Medicare Part D / Q000706:statistics & numerical data*; D008875:Middle Aged; D015999:Multivariate Analysis; D010593:Pharmaceutical Services / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D014481:United States; D014493:United States Department of Veterans Affairs / Q000706:statistics & numerical data*; D014728:Veterans / Q000706:statistics & numerical data*