Iris pigmentation and extent of disease in patients with neovascular age-related macular degeneration

To determine whether the extent of disease in age-related macular degeneration (AMD) varies with iris pigmentation. The authors assessed visual function and macular appearance in the fellow eye or both eyes of 132 white patients with unilateral neovascular AMD. All patients had a visual acuity of 20/60 or better in the fellow eye. Eighty-nine of the patients were coded as having light irides (blue, green, or hazel) and 43 were coded as having dark irides (brown); the two groups of patients had comparable mean ages. By the Mann-Whitney test for differences in mean rank, fellow eyes with light irides showed a marginally worse visual acuity (P = .156) but significantly more visual field impairment by letter recognition perimetry (P = .011) and the macular threshold test of the Humphrey Field Analyzer (P = .043), and more retinal pigment epithelial atrophy (P = .017) and focal areas of hyperpigmentation (P = .002) than fellow eyes with dark irides. For eyes with a choroidal neovascular membrane (CNVM), those with light irides had significantly lower visual acuities (P = .006) and larger scars (P = .006) than eyes with dark irides. In addition, extent of disease in the eye with a CNVM was positively correlated with extent of disease in the fellow eye for most comparisons. These observations suggest that light iris pigmentation is associated with more extensive retinal disease in patients with unilateral neovascular AMD. Furthermore, in such patients, those with worse disease in the eye with a CNVM may tend to have more extensive atrophic disease in the fellow eye.