Purpose
To assess the association between early age-related macular degeneration (AMD) and ocular/general parameters.
Methods
In 2008-2010 a total of 12,902 randomly selected national representative participants of the Korea National Health and Nutrition Examination Survey underwent additional ophthalmologic examinations by the Korean Ophthalmologic Society. The digital fundus images obtained by a digital fundus camera were graded twice using the grading protocol of the International Age-related Maculopathy Epidemiological Study Group. The independent variables were divided into five categories: 1) socio-demographic factors, 2) health examination variables, 3) Cormobidities, 4) health behavioral risk factors, and 5) variables of eyes. The risk factors for early AMD were identified using multivariate logistic regression analysis.
Results
Subjects with 5.2-12.6 g/dL of Hb(1st quintile) were more likely to have an early AMD compared to the subjects with 13.5-14.2 g/dL of Hb (3rd quintile) as a reference group (aOR=1.5, 95% CI, 1.1-2.1). In terms of spherical equivalent (SE), subjects with -22.75<SE≤-1.5 D (first quintile) were less likely to have an early AMD compared to the subjects with -0.5<SE≤0.0 D (3rd quintile) as a reference group (aOR=0.5, 95% CI, 0.3-0.8). In order to further support the result, patients with anisometric refractive error were examined. The adjusted proportion of early AMD in the right eye was lower in subjects with SE ≤-1.5D of the right eye and >-1.5D of the left eye, compared to subjects with SE >-1.5D of the right eye and ≤-1.5D of the left eye (1.6% vs 2.3%). The result was the same for subjects who develop early AMD in the left eye.
Conclusions
Age is the most important risk factor in developing an early AMD. Interestingly, positive association was found between an early AMD and anemia. Also, myopic eye is less likely to develop an early AMD.
Keywords: 412 age-related macular degeneration •
464 clinical (human) or epidemiologic studies: risk factor assessment