Improvement in quality of life from photodynamic therapy: a Canadian perspective.
BACKGROUND
The Treatment of Age-Related Macular Degeneration with Photodynamic Therapy (TAP) Study showed that at 1 year, photodynamic therapy significantly reduced the chances of severe visual loss (15 letters or greater) compared with placebo treatment in patients with "predominantly classic" subfoveal choroidal neovascularization (CNV). We performed a study to determine the expected gain in quality of life associated with photodynamic therapy for the treatment of subfoveal CNV in a Canadian cohort of patients with age-related macular degeneration.


METHODS
We created a decision analysis model to determine the incremental gain in quality-adjusted life years (QALYs) associated with photodynamic therapy over placebo over a 2-year period. The analysis was conducted using efficacy data derived from the TAP Study and patient-based utilities collected by means of the time trade-off technique. We conducted one-way and two-way sensitivity analyses to determine the robustness of our model. A Monte Carlo simulation was used to determine whether the observed gain in QALYs with photodynamic therapy was significant.


RESULTS
Photodynamic therapy was associated with a relative increase in QALYs of 11.3% compared with placebo. In one-way and two-way sensitivity analyses, the relative increase in quality of life associated with photodynamic therapy ranged from 4.2% to 25.7%. The Monte Carlo simulation showed that the gain in QALYs conferred from photodynamic therapy was statistically significant (p < 0.001).


CONCLUSIONS
Photodynamic therapy improves the quality of life of Canadians with predominantly classic subfoveal CNV secondary to age-related macular degeneration.
Sharma
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S
Cost-Effective Ocular Health Policy Unit, Queens's University, Kingston, Ont. sanjay_sharma60@hotmail.com
Hollands
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Brown
G C
GC
Brown
M M
MM
Shah
G K
GK
Sharma
S M
SM
D002170:Canada; D020256:Choroidal Neovascularization / Q000188:drug therapy* / Q000209:etiology; D015331:Cohort Studies; D003661:Decision Support Techniques; D006801:Humans; D008268:Macular Degeneration / Q000150:complications; D009010:Monte Carlo Method; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D011166:Porphyrins / Q000627:therapeutic use*; D011788:Quality of Life; D000077362:Verteporfin; D014792:Visual Acuity
D017319:Photosensitizing Agents; D011166:Porphyrins; D000077362:Verteporfin