Progression from intermediate to neovascular age-related macular degeneration according to drusen subtypes: Bundang AMD cohort study report 3.

PURPOSE To investigate the ophthalmic risk factors related to neovascular change and the subtype-wise incidence of progression from intermediate to neovascular age-related macular degeneration (AMD). METHODS In this retrospective cohort study, 632 eyes with intermediate AMD from 418 patients (older than 50 years) were enrolled. The systemic factors and ophthalmic factors were statistically analysed with respect to neovascular change. RESULTS The 5-year cumulative incidence of progression to neovascular AMD (nAMD) from intermediate AMD was 17.8% and 17.0% in eyes with soft drusen and pachydrusen (p = 0.316). Older age (p = 0.025), preexisting nAMD in the fellow eye (p < 0.001), and reticular pseudodrusen (RPD; p = 0.007) were associated with the risk of progression to nAMD. In reference to soft drusen, pachydrusen was associated with progression to polypoidal choroidal vasculopathy (PCV; p < 0.001) and not to typical nAMD (p = 0.064). CONCLUSIONS The ophthalmic risk factors related to the progression of nAMD from intermediate AMD were found to be preexisting nAMD in the fellow eye and RPD. Pachydrusen showed a similar incidence of neovascular change with soft drusen, and was associated with the progression to PCV but not to typical nAMD.