Apolipoprotein E gene and early age-related maculopathy: the Atherosclerosis Risk in Communities Study.

Kleins Lab // Publications // Feb 01 2006

PubMed ID: 16406547

Author(s): Wong TY, Shankar A, Klein R, Bray MS, Couper DJ, Klein BE, Sharrett AR, Folsom AR. Apolipoprotein E gene and early age-related maculopathy: the Atherosclerosis Risk in Communities Study. Ophthalmology. 2006 Feb;113(2):255-9. Epub 2006 Jan 10. PMID 16406547

Journal: Ophthalmology, Volume 113, Issue 2, Feb 2006

OBJECTIVE To examine the association between the apolipoprotein E (APOE) gene and early age-related maculopathy (ARM) in middle-aged persons.

DESIGN Population-based cross-sectional study.

PARTICIPANTS Participants from the Atherosclerosis Risk in Communities Study (n = 10139; age range, 49-73 years).

METHODS Retinal photography was performed on 1 randomly selected eye, and grading for presence of ARM was carried out using a modification of the Wisconsin ARM Grading System. Early ARM was defined as the presence of either soft drusen alone, retinal pigment epithelial depigmentation alone, or a combination of soft drusen with increased retinal pigment and/or depigmentation. DNA extracted from blood samples of participants were analyzed for common allelic variants of the APOE gene (epsilon2, epsilon3, and epsilon4).

MAIN OUTCOME MEASURES Presence of early ARM on retinal photographs.

RESULTS The prevalence of early ARM was similar in participants with different APOE genotypes: epsilon2/epsilon2 (5.9%), epsilon2/epsilon3 (5.2%), epsilon2/epsilon4 (3.2%), epsilon3/epsilon3 (5.2%), epsilon3/epsilon4 (4.9%), and epsilon4/epsilon4 (4.1%). After controlling for age, gender, race, cigarette smoking, and other factors, early ARM was not associated with APOE genotypes, with an odds ratio (OR) of 1.35 (95% confidence interval [CI], 0.54-3.38) for epsilon2/epsilon2 genotype, an OR of 1.06 (95% CI, 0.80-1.40) for epsilon2/epsilon3 genotype, an OR of 0.63 (95% CI, 0.32-1.24) for epsilon2/epsilon4 genotype, an OR of 0.99 (95% CI, 0.80-1.24) for epsilon3/epsilon4 genotype, and an OR of 0.88 (95% CI, 0.47-1.63) for epsilon4/epsilon4 genotype, as compared with epsilon3/epsilon3 genotype (reference). No associations were found for specific early ARM signs or in analyses stratified by age, gender, race, or cigarette smoking status.

CONCLUSIONS These data provide no evidence of a strong association between the APOE gene and early ARM in middle-aged persons. This suggests that APOE is not likely a major determinant of the early stages of ARM in younger people. However, our study does not exclude the possibility of a weaker association or that APOE may influence only the development of late ARM in older populations, as reported in other studies.