Progressive visual loss in subfoveal exudation in age-related macular degeneration: a meta-analysis using Lineweaver-Burke plots.
OBJECTIVE
To analyze the randomized clinical trials in exudative age-related macular degeneration (AMD) to reveal apparent differences in the behavior of untreated control eyes among these trials. Herein we test the hypothesis that the behavior of untreated control eyes is actually the same in all studies, with apparent differences arising from differences in the time of entry of eyes into clinical trials.


METHODS
Retrospective meta-analysis of prior clinical trials.


METHODS
Control eye data from six AMD studies (Macular Photocoagulation Study, Subfoveal Surgery Trial, Photodynamic Therapy [TAP] With Visudyne, pegaptanib trial for neovascular AMD, anecortave acetate trial, and 360 degree Macular Translocation Study) were plotted on a double reciprocal plot of 1/(Letters Lost) vs 1/(Months After Enrollment). To account for differences in time of entry into clinical trials, we introduced a horizontal translation factor to shift each data subset horizontally to maximize r(2) for the cumulative trend line.


RESULTS
Cumulative data for untreated control eyes fits a straight line on a double reciprocal plot (r(2) = .9521); an untreated eye would eventually deteriorate to a final vision of 20/640. The slope of the line predicts that patients would experience half of the maximum final vision within 10.88 months after exudation onset.


CONCLUSIONS
The pattern of vision loss experienced in AMD eyes with subfoveal neovascularization is uniform across a wide range of clinical trials, with apparent differences arising from differences in the time of entry of patients into clinical trials.
Shah
Ankoor R
AR
Department of Ophthalmology, Columbia University, 635 West 165th Street, New York, NY 10032, USA.
Del Priore
Lucian V
LV
D020533:Angiogenesis Inhibitors / Q000627:therapeutic use; D052157:Aptamers, Nucleotide / Q000627:therapeutic use; D001766:Blindness / Q000503:physiopathology*; D020256:Choroidal Neovascularization / Q000503:physiopathology* / Q000628:therapy; D018450:Disease Progression; D005122:Exudates and Transudates; D006801:Humans; D008266:Macula Lutea / Q000637:transplantation; D008268:Macular Degeneration / Q000503:physiopathology* / Q000628:therapy; D010778:Photochemotherapy; D011244:Pregnadienediols / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D014792:Visual Acuity / Q000502:physiology
D020533:Angiogenesis Inhibitors; D052157:Aptamers, Nucleotide; D011244:Pregnadienediols; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C495058:pegaptanib; C418047:anecortave acetate