title: Did Medicare Part D reduce disparities?
abstract: OBJECTIVE
  We assessed whether Medicare Part D reduced disparities in access to medication.
  
  
  METHODS
  Secondary data analysis of a 20% sample of Medicare beneficiaries, using Parts A and B medical claims from 2002 to 2008 and Part D drug claims from 2006 to 2008.
  
  
  METHODS
  We analyzed the medication use of Hispanic, black, and white beneficiaries with diabetes before and after reaching the Part D coverage gap, and compared their use with that of race-specific reference groups not exposed to the loss in coverage. Unadjusted difference-in-difference results were validated with multivariate regression models adjusted for demographics, comorbidities, and zip code-level household income used as a proxy for socioeconomic status.
  
  
  RESULTS
  The rate at which Hispanics reduced use of diabetes-related medications in the coverage gap was twice as high as whites, while blacks decreased their use of diabetes-related medications by 33% more than whites. The reduction in medication use was correlated with drug price. Hispanics and blacks were more likely than whites to discontinue a therapy after reaching the coverage gap but more likely to resume once coverage restarted. Hispanics without subsidies and living in low-income areas reduced medication use more than similar blacks and whites in the coverage gap.
  
  
  CONCLUSIONS
  We found that the Part D coverage gap is particularly disruptive to minorities and those living in low-income areas. The implications of this work suggest that protecting the health of vulnerable groups requires more than premium subsidies. Patient education may be a first step, but more substantive improvements in adherence may require changes in healthcare delivery.
authors.affiliation: Schaeffer Center for Health Policy and Economics, University of Southern California, 635 Downey Way, Los Angeles, CA 90089-3331.Tel: 213-821-7947; Fax: 213-740-3460. E-mail: zissimop@usc.edu.
authors.forename: Julie
authors.initials: J
authors.lastname: Zissimopoulos
authors.forename: Geoffrey F
authors.initials: GF
authors.lastname: Joyce
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Scarpati
authors.forename: Dana P
authors.initials: DP
authors.lastname: Goldman
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D016208:Databases, Factual; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000188:drug therapy* / Q000191:economics; D005260:Female; D054625:Healthcare Disparities / Q000208:ethnology* / Q000706:statistics & numerical data*; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D007004:Hypoglycemic Agents / Q000191:economics / Q000627:therapeutic use; D008297:Male; D054524:Medicare Part D / Q000191:economics* / Q000706:statistics & numerical data; D055118:Medication Adherence / Q000208:ethnology*; D015999:Multivariate Analysis; D011203:Poverty; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D014481:United States; D044465:White People / Q000706:statistics & numerical data; D016903:Drug Monitoring
chemical_list: D007004:Hypoglycemic Agents