title: Long-term medical management of primary open-angle glaucoma and ocular hypertension in the UK: optimizing cost-effectiveness and clinic resources by minimizing therapy switches.
abstract: OBJECTIVE
  The objective was to assess the long-term economic consequences of the medical management of glaucoma in the UK.
  
  
  METHODS
  The economic evaluation was conducted using the results from a 10-year Markov model based around 3 key triggers for a switch in medical therapy for glaucoma, namely: lack of tolerance (using hyperemia as a proxy); intraocular pressure (IOP) not meeting treatment benchmark; and glaucoma progression. Clinical data from a comprehensive systematic literature review and meta-analysis were used. Direct costs associated with glaucoma treatment are considered (at 2008/9 prices) from the perspective of the UK NHS as payer (outpatient/secondary care setting). Using this model, the economic consequences of 3 prostaglandin-based treatment sequences were compared.
  
  
  RESULTS
  Drug acquisition costs account for around 8% to 13% of the total cost of glaucoma and, if ophthalmologist visits are included, amount to approximately £0.80 to £0.90 per day of medical therapy. The total long-term costs of all prostaglandin strategies are similar because of a shift in resources: increased drug costs are offset by fewer clinic visits to instigate treatment switches, and by avoiding surgery or costs associated with managing low vision. Under the latanoprost-based strategy, patients would have longer intervals between the need to switch therapies, which is largely due to a reduction in hyperemia, seen as a proxy for tolerance. This leads to a delay in glaucoma progression of 12 to 13 months. For every 1000 clinic appointments, 719 patients can be managed for 1 year with a latanoprost-based strategy compared with 586 or 568 with a bimatoprost or travoprost-based strategy.
  
  
  CONCLUSIONS
  Drug acquisition costs are not a key driver of the total cost of glaucoma management and the cost of medical therapy is offset by avoiding the cost of managing low vision. Economic models of glaucoma should include the long-term consequences of treatment as these will affect cost-effectiveness. This analysis supports the hypothesis that the economic and clinical benefits can be optimized by minimizing therapy switches.
authors.affiliation: Abacus International, Bicester, Oxfordshire, UK.
authors.forename: Michelle
authors.initials: M
authors.lastname: Orme
authors.forename: Sarah
authors.initials: S
authors.lastname: Collins
authors.forename: Jane
authors.initials: J
authors.lastname: Loftus
mesh_terms: D000368:Aged; D000577:Amides / Q000191:economics / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000191:economics* / Q000627:therapeutic use; D000069580:Bimatoprost; D003008:Cloprostenol / Q000031:analogs & derivatives / Q000191:economics / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D016527:Drug Costs; D057915:Drug Substitution; D005260:Female; D005500:Follow-Up Studies; D005902:Glaucoma, Open-Angle / Q000188:drug therapy* / Q000191:economics*; D017048:Health Care Costs; D006295:Health Resources / Q000706:statistics & numerical data*; D006801:Humans; D007429:Intraocular Pressure; D000077338:Latanoprost; D008297:Male; D008390:Markov Chains; D018803:Models, Economic; D009798:Ocular Hypertension / Q000188:drug therapy / Q000191:economics; D011461:Prostaglandins F, Synthetic / Q000191:economics / Q000627:therapeutic use; D000069557:Travoprost; D006113:United Kingdom
chemical_list: D000577:Amides; D000959:Antihypertensive Agents; D011461:Prostaglandins F, Synthetic; D003008:Cloprostenol; D000077338:Latanoprost; D000069580:Bimatoprost; D000069557:Travoprost