Trends in Myopia and High Myopia from 1966 to 2019 in Olmsted County, Minnesota

Abstract

PurposeTo investigate the prevalence of myopia and high myopia in Olmsted County, Minnesota from 1966-2019. DesignRetrospective cross-sectional, trend study using a random population-based sample in Olmsted County, Minnesota from 1966-2019. MethodsManifest refractions or lens prescription were converted to spherical equivalent (SE) to estimate prevalence of adult myopia and high myopia. Age, sex, race, and visual acuity were recorded. Subjects with SE ≤-0.5 diopters (D) were considered myopic; ≤-6.0 D were considered high myopia. Exclusion criteria included visually significant cataract, pseudophakia, prior refractive surgery, or age <18 years-old. ResultsAmong 81,706 sampled subjects, myopia prevalence increased from 33.9% (95% CI 31.1-36.8) in 1960s to 57.1% (95% CI, 56.6-57.6) in 2010s (p<0.001). High myopia prevalence increased from 2.8% (95% CI, 1.95-3.98) in 1960s to 8.3% (95% CI, 8.08-8.62) in 2010s (p<0.001). Both males (32.0%-55.1%, p<.001) and females (40.6%-58.5%, p<.001) experienced increasing myopia prevalence from 1960s-2010s while males (2.6%-7.4%, p<.001) and females (3.4%-9.1%, p<.001) also had higher high myopia prevalence rates from 1960s through 2010s. Increasing myopia and high myopia prevalence was detected by decade in nearly all age groups (excluding 18-24-year-old high myopia subjects). White and Asian subjects had the highest myopia prevalence while Black subjects had the lowest. From the 2000s-2010s, White (53.3%-57.0%, p<0.001) and Black (41.0%-47.0%, p=0.001) subjects had significant increases in myopia prevalence. Mean SE decreased from the 1960s (-0.42 D; 95% CI -0.59-+2.49) to 2010s (-1.85 D; 95% CI, -1.88-+2.96) (p<0.001). ConclusionsFrom 1966-2019 in Olmsted County, Minnesota, there was a 68% and 199% increase in myopia and high myopia prevalence, respectively.