title: Are older Western Australians exposed to potentially inappropriate medications according to the Beers Criteria? A 13-year prevalence study.
abstract: OBJECTIVE
  To examine time trends and factors associated with exposure to potentially inappropriate medications (PIMs) by the Beers Criteria.
  
  
  METHODS
  PIM consumption days accumulated from the pharmaceutical claims of 251 305 Western Australians aged ≥65 years (1993-2005) and person follow-up times produced counts/rates. Logistic/Poisson regression generated odds/rate ratios.
  
  
  RESULTS
  A total of 187 616 participants (74.7%) took ≥1 PIM (1993-2005), the cohort consuming 109 415 PIM daily doses/1000 person-years. Annual exposure decreased from 45-47% to 40%, and annual consumption rate declined from 117 836 to 90 364 daily doses/1000 person-years. Temazepam had the highest exposures (>17 000 daily doses/1000 person-years). Number of medications taken (OR 35.03; 95% CI 34.37-35.71 for ≥10 vs. 0-2 drugs), annual drug intake (2.08; 2.04-2.12 for highest vs. lowest quartile), and high-level residential aged care (1.96; 1.91-2.01) were most predictive of PIM exposure.
  
  
  CONCLUSIONS
  PIM exposure remains high in older Western Australians. Our findings identify patients most at risk and medications to consider on Australia-specific PIM lists.
authors.affiliation: School of Population Health, The University of Western Australia, Perth, Australia.
authors.forename: Sylvie D
authors.initials: SD
authors.lastname: Price
authors.forename: C D'Arcy J
authors.initials: CD
authors.lastname: Holman
authors.forename: Frank M
authors.initials: FM
authors.lastname: Sanfilippo
authors.forename: Jon D
authors.initials: JD
authors.lastname: Emery
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D004347:Drug Interactions; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects; D057970:Inappropriate Prescribing / Q000639:trends*; D007356:Insurance, Pharmaceutical Services; D016015:Logistic Models; D008297:Male; D008508:Medication Errors / Q000639:trends*; D015999:Multivariate Analysis; D016017:Odds Ratio; D019338:Polypharmacy; D012307:Risk Factors; D013693:Temazepam / Q000009:adverse effects; D013997:Time Factors; D014904:Western Australia
chemical_list: D006993:Hypnotics and Sedatives; D013693:Temazepam
keywords: Western Australia; aged; inappropriate prescribing; prevalence; risk factor