title: Racial and Ethnic Differences in Initiation and Discontinuation of Antidementia Drugs by Medicare Beneficiaries.
abstract: To examine racial and ethnic differences in initiation and time to discontinuation of antidementia medication in Medicare beneficiaries.
  
  
  
  Retrospective cohort study.
  
  
  
  Secondary analysis of 2009-10 enrollment, claims, and Part D prescription data for a 10% national sample of U.S. Medicare fee-for-service beneficiaries.
  
  
  
  Beneficiaries aged 65 and older with Alzheimer's disease or related dementia (ADRD) before 2009 and no fills for antidementia medications in the first half of 2009 (N = 84,043).
  
  
  
  Initiation was defined as having one or more fills for antidementia medication in the second half of 2009 and discontinuation as a gap in coverage of 30 days or more during the year after initiation. The Andersen Behavioral Model was used to guide covariate selection.
  
  
  
  Overall, 3,481 (4.1%) of previous nonusers initiated antidementia medication in the second half of 2009. Of those initiating one drug class (acetylcholinesterase inhibitors (AChEIs) or memantine), 9% later added the other class, and 2% switched classes. Of initiators, 23% discontinued within 1 month, and 62% discontinued within 1 year. Hispanic beneficiaries were more likely than white beneficiaries to initiate (adjusted odds ratio = 1.25, 95% confidence interval (CI) = 1.10-1.41). Black and white beneficiaries did not differ in likelihood of initiation. Hispanic (adjusted hazard ratio (aHR) = 1.56, 95% CI = 1.34-1.82) and black (aHR = 1.25, 95% CI = 1.08-1.44) beneficiaries discontinued at a faster rate than white beneficiaries.
  
  
  
  Initiation of antidementia medications was no different in black and white beneficiaries and more likely in Hispanic beneficiaries; black and Hispanic beneficiaries discontinued at a faster rate. More research into reasons explaining these differences is needed.
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania. ctthorpe@pitt.edu.|Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania. ctthorpe@pitt.edu.
authors.forename: Carolyn T
authors.initials: CT
authors.lastname: Thorpe
authors.affiliation: School of Medicine and Center for Aging Research, Indiana University, Indianapolis, Indiana.|Center for Health Innovation and Implementation, Regenstrief Institute, Inc., Indianapolis, Indiana.
authors.forename: Nicole R
authors.initials: NR
authors.lastname: Fowler
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Katherine
authors.initials: K
authors.lastname: Harrigan
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.|Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.|Division of Geriatric Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Division of Geriatric Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Yihuang
authors.initials: Y
authors.lastname: Kang
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.|Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.|Division of Geriatric Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Hanlon
authors.affiliation: Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.|Division of General Internal Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Walid F
authors.initials: WF
authors.lastname: Gellad
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.|Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.
authors.forename: Loren J
authors.initials: LJ
authors.lastname: Schleiden
authors.affiliation: Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.|Center for Health Equity Research and Promotion, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Thorpe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000188:drug therapy* / Q000453:epidemiology / Q000208:ethnology*; D044383:Black People / Q000706:statistics & numerical data*; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D003431:Cross-Cultural Comparison; D057915:Drug Substitution / Q000706:statistics & numerical data; D004359:Drug Therapy, Combination / Q000706:statistics & numerical data; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data*; D055118:Medication Adherence / Q000208:ethnology*; D008559:Memantine / Q000627:therapeutic use; D018697:Nootropic Agents / Q000627:therapeutic use*; D016017:Odds Ratio; D012189:Retrospective Studies; D014481:United States; D044465:White People / Q000706:statistics & numerical data*; D001741:Black or African American; D016903:Drug Monitoring
chemical_list: D002800:Cholinesterase Inhibitors; D018697:Nootropic Agents; D008559:Memantine
keywords: Medicare; antidementia medications; dementia; health disparities; medication discontinuation