To assess the association between correction of myopia, hyperopia and astigmatism with self-reported near and distance visual function.
Population based, cross-sectional study.
A random sample of 4272 Latinos over 40 years old from Arizona with both ophthalmic exam and questionnaire data, including answers to the NEI VFQ-25.
Cases of refractive error (RE) were defined as subjects who met at least one of the following criteria in both eyes: myopia, sphere ≤-0.5 diopters (D); hyperopia, sphere ≥1.0D; astigmatism, cylinder≥0.75D. Uncorrected refractive error (URE) was defined as having RE and achieving ≥2 line improvement in visual acuity in both eyes after refraction. The association between RE category and near and distance vision difficulty (as measured by the National Eye Institute Visual Functioning Questionnare-25 near and distance vision subscores) was modeled with ordinal logistic regression, adjusting for age, sex, diabetes, hypertension, income, education and acculturation.
Main Outcome Measures
Association between RE correction and near and distance vision difficulty by type of RE (myopia, hyperopia, and astigmatism).
Of 4272 participants, 54% had RE. 48% of these had myopia, 41% hyperopia, and 11% astigmatism. 14% of myopes, 21% of hyperopes, and 22% of astigmatics had URE. Subjects with myopia, astigmatism, and hyperopia were significantly more likely to report more distance vision difficulty than subjects without RE, whether or not they had correction (Odds Ratios (OR) from 1.7-3.7; p<0.005 for all). Subjects with corrected myopia reported less near vision difficulty than subjects without RE (OR 0.8, Confidence Interval (CI) 0.7-0.9). Subjects with uncorrected hyperopia and uncorrected astigmatism reported more near vision difficulty than those without RE (OR 1.6, CI 1.2-2.2 and OR 1.7, CI 1.0-3.0, respectively). Self reported distance and near visual function scores were sensitive to non-vision variables; namely, age, sex, diabetes, high blood pressure, acculturation score, income, and education.
in our population, correction of any type of RE is not entirely sufficient to restore distance visual function to the level of those without RE. More research is necessary to determine the reasons for this shortcoming.