title: Impact of Part D low-income subsidies on medication patterns for Medicare beneficiaries with diabetes.
abstract: BACKGROUND
  It is not known whether low-income subsidies (LIS) under Medicare Part D help beneficiaries overcome impediments to medication use associated with poor socioeconomic status and high disease burden.
  
  
  OBJECTIVE
  To compare Medicare beneficiaries with LIS and Medicaid (duals), LIS without dual eligibility, and non-LIS recipients on use of medications recommended in diabetes treatment.
  
  
  METHODS
  Fixed-effect comparisons among beneficiaries in the same Part D plans in 2006-2007.
  
  
  METHODS
  Nationally representative sample of enrollees in Part D prescription drug plans. A total of 109,292 beneficiaries were in 204 prescription drug plans; 47.5% non-LIS, 44.4% duals, and 8.1% nondual LIS recipients.
  
  
  METHODS
  Medications included antidiabetic agents, renin-angiotensin-aldosterone system inhibitors, and antihyperlipidemics. Drug use was measured by exposure, duration of therapy, and medication possession ratio.
  
  
  RESULTS
  The LIS dual cohort had significantly higher comorbidity compared with non-LIS comparisons, LIS nonduals were significantly more likely to take medications in all 3 drug classes compared with non-LIS recipients, but differences were small (between 2% and 4%; P<0.05). Non-LIS recipients and duals had equivalent exposure to any antidiabetic drug and antihyperlipidemics, but duals were 3% less likely to receive renin-angiotensin-aldosterone system inhibitors compared with non-LIS recipients (P<0.05). Small differences in adjusted values for duration of therapy and medication possession ratio among the 3 cohorts were also observed, none of which were clinically meaningful.
  
  
  CONCLUSIONS
  Similarities in medication utilization among Part D enrollees with and without LIS coverage supports the program objective of providing enhanced access to needed medications for diverse groups of Medicare beneficiaries.
authors.affiliation: Pharmaceutical Health Services Research Department, The Peter Lamy Center on Drug Therapy and Aging, University of Maryland School of Pharmacy, Baltimore, MD, USA.
authors.forename: Bruce
authors.initials: B
authors.lastname: Stuart
authors.forename: Xianghua
authors.initials: X
authors.lastname: Yin
authors.forename: Amy
authors.initials: A
authors.lastname: Davidoff
authors.forename: Linda
authors.initials: L
authors.lastname: Simoni-Wastila
authors.forename: Ilene
authors.initials: I
authors.lastname: Zuckerman
authors.forename: J Samantha
authors.initials: JS
authors.lastname: Shoemaker
authors.forename: Jalpa
authors.initials: J
authors.lastname: Doshi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000191:economics*; D008078:Cholesterol, LDL / Q000097:blood; D003920:Diabetes Mellitus / Q000188:drug therapy* / Q000453:epidemiology; D004363:Drug Utilization / Q000191:economics*; D005260:Female; D006442:Glycated Hemoglobin; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000191:economics*; D000960:Hypolipidemic Agents / Q000008:administration & dosage / Q000191:economics*; D008297:Male; D054524:Medicare Part D / Q000706:statistics & numerical data; D011203:Poverty / Q000706:statistics & numerical data; D011632:Public Assistance / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D014481:United States; D016903:Drug Monitoring
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D008078:Cholesterol, LDL; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D000960:Hypolipidemic Agents