title: Osteoporosis medication prescribing in British Columbia and Ontario: impact of public drug coverage.
abstract: We compared the patterns of osteoporosis medication prescribing between two provinces in Canada with different public drug coverage policies. Oral bisphosphonates were the primary drugs used, yet access to the second-generation oral bisphosphonates (alendronate, risedronate) was limited in one region. Implications of differential access to oral bisphosphonates warrants further study.
  
  
  BACKGROUND
  Approved therapies for treating osteoporosis in Canada include bisphosphonates, calcitonin, denosumab, raloxifene, and teriparatide. However, significant variation in access to these medications through public drug coverage exists across Canada. We sought to compare patterns of osteoporosis medication prescribing between British Columbia (BC) and Ontario.
  
  
  METHODS
  Using dispensing data from BC (PharmaNet) and Ontario (Ontario Drug Benefits), we identified all new users of osteoporosis medications aged 66 or more years from 1995/1996 to 2008/2009. We summarized the number of new users by fiscal year, sex, and index drug for each province. BC data were also stratified by whether drugs were dispensed within or outside public PharmaCare.
  
  
  RESULTS
  We identified 578,254 (n = 122,653 BC) eligible new users. Overall patterns were similar between provinces: (1) most patients received an oral bisphosphonate (93% in BC and 99% in Ontario); (2) etidronate prescribing declined after 2001/2002, reaching a low of 41% in BC and 10% in Ontario in 2008/2009; and (3) the proportion of males treated increased over time, from 7% in 1996/1997 to 25% in 2008/2009. However, we note major differences within versus outside the BC PharmaCare system. In particular, <2% of drugs dispensed within PharmaCare compared to 79% of drugs dispensed outside PharmaCare were for a second-generation bisphosphonate (alendronate or risedronate).
  
  
  CONCLUSIONS
  Oral bisphosphonates are the primary drugs used to treat osteoporosis in Canada. Prescribing practices changed over time as newer medications came to market, yet access to second-generation bisphosphonates through BC PharmaCare was limited. Implications of differential access to oral bisphosphonates warrants further study.
authors: Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, M5S 3M2, ON, Canada. s.cadarette@utoronto.ca
authors: S M
authors: SM
authors: Cadarette
authors: G
authors: G
authors: Carney
authors: D
authors: D
authors: Baek
authors: N
authors: N
authors: Gunraj
authors: J M
authors: JM
authors: Paterson
authors: C R
authors: CR
authors: Dormuth
mesh_terms: D000368:Aged; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D001955:British Columbia; D004164:Diphosphonates / Q000627:therapeutic use; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D004363:Drug Utilization / Q000706:statistics & numerical data / Q000639:trends; D005260:Female; D006801:Humans; D019458:Insurance Coverage; D008297:Male; D009864:Ontario; D010024:Osteoporosis / Q000188:drug therapy*; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data* / Q000639:trends; D012737:Sex Factors; D013222:State Medicine / Q000706:statistics & numerical data
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates