title: The cost-effectiveness of photodynamic therapy for fellow eyes with subfoveal choroidal neovascularization secondary to age-related macular degeneration.
abstract: OBJECTIVE
  Photodynamic therapy (PDT) has recently been demonstrated to be beneficial for the treatment of subfoveal choroidal neovascularization secondary to age-related macular degeneration (AMD). Herein, we determine the cost-effectiveness of PDT for the treatment of subfoveal choroidal neovascularization (CNV) in patients with disciform degeneration in one eye and whose second and better-seeing eye develops visual loss secondary to predominantly classic subfoveal CNV. The analysis was performed from the perspective of a for-profit third-party insurer.
  
  
  METHODS
  Cost-utility Markov models were created to determine the cost-effectiveness of PDT under two different scenarios, by using efficacy data derived from the Treatment of Age-Related Macular Degeneration with Photodynamic Therapy (TAP) Study and patient-based utilities.
  
  
  METHODS
  Decision analyses were performed by incorporating data from the TAP Study, expected longevity data, and patient-based utilities. Cost-effective models were then created by incorporating incremental medical costs. Various sensitivity analyses were carried out to determine the robustness of our models. A Monte Carlo simulation was also used to determine whether there was a significant difference in quality-of-life adjusted years (QALYs) gained between PDT therapy and the placebo.
  
  
  RESULTS
  For the hypothetical patient whose second and better-seeing eye becomes affected and who has 20/40 vision at baseline in this affected eye (base case 1), PDT was associated with a 10.7% relative increase in their quality-of-life (treatment conferred an additional undiscounted 0.1342 QALYs over a 2-year period). For the hypothetical patient whose second and better-seeing eye becomes affected and who has 20/200 vision at baseline in this affected eye (base case 2), PDT was associated with a 7.8% relative increase in their quality-of-life (treatment conferred an additional undiscounted 0.0669 QALYs over a 2-year period). Sensitivity analysis showed our models were robust and that PDT was usually the dominant treatment choice. Our cost-effective model demonstrated that the cost for a QALY was $86,721 (US dollars discounted at 3%) for base case 1, assuming 5.5 treatments; and $173,984 (USD discounted at 3%) for base case 2.
  
  
  CONCLUSIONS
  PDT will cost a third-party insurer $86,721 for an AMD patient with 20/40 vision in the better-seeing eye to obtain one QALY and $173,984 for an AMD patient with 20/200 vision in the better-seeing eye to obtain one QALY. PDT can be considered to be a treatment that is of only minimal cost-effectiveness for AMD patients who have subfoveal CNV in their second and better-seeing eyes and who have good presenting visual acuity at baseline. It is a cost-ineffective treatment for AMD patients who have poor visual acuities in their affected better-seeing eyes.
authors.affiliation: The Cost-Effective Ocular Health Policy Unit, Hotel Dieu Hospital, Queen's University, Kingston, Ontario, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Sharma
authors.forename: G C
authors.initials: GC
authors.lastname: Brown
authors.forename: M M
authors.initials: MM
authors.lastname: Brown
authors.forename: H
authors.initials: H
authors.lastname: Hollands
authors.forename: G K
authors.initials: GK
authors.lastname: Shah
mesh_terms: D000368:Aged; D020256:Choroidal Neovascularization / Q000188:drug therapy / Q000191:economics* / Q000209:etiology; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D005584:Fovea Centralis / Q000098:blood supply; D006801:Humans; D008268:Macular Degeneration / Q000150:complications / Q000191:economics*; D008390:Markov Chains; D017059:Models, Econometric; D009010:Monte Carlo Method; D010778:Photochemotherapy / Q000191:economics*; D017319:Photosensitizing Agents / Q000191:economics / Q000627:therapeutic use; D019057:Quality-Adjusted Life Years; D014792:Visual Acuity
chemical_list: D017319:Photosensitizing Agents