Abstract
Purpose: :
To characterize the magnitude and type of refractive change in a population-based sample of Latinos aged 40 years and older over a 4-year period.
Methods: :
A population-based cohort of 4568 self-identified Latinos from six census tracts in Los Angeles, California, underwent comprehensive ophthalmological examinations at baseline and at four year follow-up, including visual acuity measurements and automated and subjective non-cycloplegic refraction using standardized protocols. Subjects who were aphakic or pseudophakic on examination were excluded from this analysis. Data from one randomly selected eye from each participant were used in this analysis. Analysis of variance (ANOVA) and chi-square test were used to assess differences in the means and proportions between the groups.
Results: :
Of the 4568 participants who underwent both a baseline and a follow-up examination, 4066 were included in this analysis. Overall, 1119 of the 4066 participants (27.5%) had no change in their refractive error. The proportion of participants aged 40-49 years, 50-59 years, 60-69 years, 70-79 years and 80 years and older at baseline who had no change in their refractive error was 42.1%, 22%, 14.2%, 9.7%, and 5.7%, respectively (p-trend =< 0.001). The median (mean) change in spherical equivalent refractive error in diopters (D) in those aged 40-49 years, 50-59 years, 60-69 years, 70-79 years and 80 years and older at baseline was 0D (+0.1D), +0.25D (+0.26D), +0.13D (+0.04D), -0.13D (-0.27D) and -0.37D (-0.5D), respectively (p-trend =< 0.001). There were no gender-related differences within each age group. The proportion of participants aged 40-49 years, 50-59 years, 60-69 years, 70-79 years and 80 years and older at baseline who had a greater than or equal to -1D myopic change was 10.7%, 7.9%, 18.4%, 32.8%, and 45.7%, respectively.
Conclusions: :
In a population-based sample of Latinos, younger Latinos (40-69 years) have a hyperopic shift in their refractive error, which is followed by a myopic shift in those who are older (70 years and older). The tendency toward myopic shift in the older patients is most likely attributable to progressive lenticular changes.
Keywords: refractive error development • aging: visual performance • clinical (human) or epidemiologic studies: prevalence/incidence