Abstract
Purpose::
To determine the risk factors for the 2-year incidence and progression of age-related macular degeneration (AMD) in a racially heterogeneous, older population.
Methods::
A total of 2240 subjects underwent baseline examination and follow-up 2 years later. Fundus photography was performed at both sessions and was graded by trained, masked readers. Multivariate logistic regression models adjusting for age, sex, race, and clustering between eyes were used to determine risk factors for AMD progression.
Results::
Current smoking was a strong, dose dependent, risk factor for progression from medium-sized drusen to large drusen or pigmentary abnormalities within the central 1500 micron perimacular zone. Smoking was not associated with the progression from central large drusen or pigmentary abnormalities to foveal geographic atrophy (GA) or choroidal neovascularization (CNV). Caucasians were significantly more likely than African-Americans to develop large central drusen, develop central pigmentary abnormalities, and progress from medium-sized drusen to large drusen or pigmentary abnormalities within the central 1500 micron macular zone. However, Caucasians did not have an increased risk of progression from large drusen or pigmentary abnormalities within the central 1500 micron perimacular zone to foveal GA or CNV.
Conclusions::
Smoking and race are important risk factors in the progression from medium-sized drusen to large drusen or pigmentary abnormalities within the central 1500 micron macular zone. However, it is unclear whether smoking and race may have less of an impact on the ultimate progression to foveal GA or CNV once central large drusen or pigmentary abnormalities are present.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: risk factor assessment