Numerous population-based epidemiologic studies1- 3 have reported on the prevalence, incidence, and risk factors of age-related macular degeneration (AMD) in the United States and globally. One such study1 suggests that 6% to 8% of adults 40 years and older have signs of early-stage AMD. However, few patients develop late AMD, the most sight-threatening stage of AMD, which includes neovascular AMD and geographic atrophy; the 5-year incidence of advanced or late AMD has been reported to be 0.6% to 1.1% among adults 40 years and older.1,2 The ability to identify this group of high-risk individuals is important for patient counseling and monitoring and will be even more crucial as new therapies that aim to slow the progression to late AMD enter into clinical trials. In this regard, older age and cigarette smoking are the 2 most consistent systemic predictors associated with increased risk of development of incident late AMD.1- 3 In contrast to systemic factors, the ocular phenotype based on drusen characteristics and pigmentary abnormalities has a much stronger predictive power of progression to advanced AMD, with 5-year rates ranging from less than 1% in patients with mild changes to as high as 50% in patients with large drusen and pigmentary changes bilaterally.2 These data underlie the need to develop a risk score of AMD based on assessment of the ocular phenotype.
Cheung CMG, Wong TY. Clinical Relevance and Application of the Age-Related Eye Disease Study Severity Scale for Age-Related Macular Degeneration. JAMA Ophthalmol. 2016;134(9):1047-1048. doi:10.1001/jamaophthalmol.2016.2407