title: Influence of socioeconomic status on drug selection for the elderly in Canada.
abstract: OBJECTIVE
  To examine the association between socioeconomic status, as indicated by neighborhood median income levels, and physician drug selection between older, less expensive generic drugs and newer, more expensive brand-name drugs for elderly patients initiating drug therapy in a universal healthcare system.
  
  
  METHODS
  We conducted a population-based, retrospective, cross-sectional study. Using healthcare administrative databases, we assessed the medication profiles of 128 314 patients from more than 1.4 million residents of Ontario > or =65 years old initiating antipsychotic, hydroxymethylglutaryl-coenzyme A reductase inhibitor (statin), or ocular beta-blocker drug therapy from January 1, 1998, through December 31, 1999. We examined the selection of older generic drugs relative to newer brand-name agents for patients in each of 5 income quintiles.
  
  
  RESULTS
  Overall, brand-name drug prescribing modestly increased with increasing income quintile after adjusting for patient age and gender (61.2% in the lowest income quintile vs. 64.1% in the highest income quintile; p value for trend < 0.001). Significant risk ratios comparing the highest with the lowest income-quintile patients were observed for selection of newer, brand-name antipsychotics (RR 1.14; 95% CI 1.06 to 1.23), older generic statins (RR 0.86; 95% CI 0.77 to 0.95), and newer, brand-name ocular beta-blockers (RR 1.13; 95% CI 1.02 to 1.25).
  
  
  CONCLUSIONS
  This study suggests that income-related differences in treatment selection by physicians may exist. The reasons for these differences and subsequent impact on health outcomes warrant further investigation.
authors.affiliation: Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue-G215, Toronto, Ontario M4N 3M5, Canada. muhammad.mamdani@ices.on.ca
authors.forename: Muhammad M
authors.initials: MM
authors.lastname: Mamdani
authors.forename: Karen
authors.initials: K
authors.lastname: Tu
authors.forename: Peter C
authors.initials: PC
authors.lastname: Austin
authors.forename: David A
authors.initials: DA
authors.lastname: Alter
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D014150:Antipsychotic Agents / Q000627:therapeutic use; D002170:Canada; D003430:Cross-Sectional Studies; D016208:Databases, Factual; D011307:Drug Prescriptions / Q000191:economics / Q000706:statistics & numerical data*; D004358:Drug Therapy / Q000191:economics / Q000706:statistics & numerical data*; D016568:Drugs, Generic / Q000627:therapeutic use; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D008297:Male; D012189:Retrospective Studies; D012923:Social Class; D019472:Universal Health Insurance / Q000191:economics / Q000706:statistics & numerical data
chemical_list: D000319:Adrenergic beta-Antagonists; D014150:Antipsychotic Agents; D016568:Drugs, Generic; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors