Refractive error and age-related maculopathy: the Blue Mountains Eye Study

Abstract

Purpose: To assess associations between refractive error (hyperopia, myopia, and spherical equivalent [SEq]) and age-related maculopathy (ARM) in an older population.

Methods: A population-based survey examined 3654 people aged 49 years or older, 82% of whom were permanent residents in an area west of Sydney, Australia. Participants had a detailed eye examination, including standardized refraction and stereo macular photographs. ARM was diagnosed from blinded photographic grading. Autorefractor measurements and subjective refraction were used to assess SEq refractive error for each eye in diopters. Mean SEq of the two eyes was used to define emmetropia, myopia, and hyperopia in each person.

Results: After known ARM risk factors (age, sex, ARM family history, current smoking) had been adjusted for, no association was found between mean SEq (two eyes) and late ARM (odds ratio [OR], 1.0; 95% confidence interval [CI], 0.9-1.1). However, a statistically significant increased risk of early ARM was found for each diopter of increase in mean SEq (OR, 1.1; CI, 1.0-1.2). In logistic regression models, moderate to high hyperopia was significantly associated with increased early ARM risk (OR, 2.0; CI, 1.2-3.4). When a generalized estimating equation model (GEE), which assessed the relationship at eye level while accounting for the correlation between the two eyes, was used, this association was marginally insignificant (OR, 1.3; CI, 0.9-1.9). No significant associations were found between myopia and any ARM stage with either model.

Conclusions: These population-based data suggest a weak association between hyperopia and early ARM.