Uncorrected refractive error in older British adults: the EPIC-Norfolk Eye Study

Aim To investigate the prevalence of, and demographic associations with, uncorrected refractive error (URE) in an older British population. Methods Data from 4428 participants, aged 48-89 years, who attended an eye examination in the third health check of the European Prospective Investigation into Cancer-Norfolk study and had also undergone an ophthalmic examination were assessed. URE was defined as >= 1 line improvement of visual acuity with pinhole-correction in the better eye in participants with LogMar presenting visual acuity (PVA) <0.3 (PVA <6/12). Refractive error was measured using an autorefractor without cycloplegia. Myopia was defined as spherical equivalent <=-0.5 dioptre, and hypermetropia >= 0.5 dioptre. Results Adjusted to the 2010 midyear British population, the prevalence of URE in this Norfolk population was 1.9% (95% CI 0.6% to 3.1%). Lower self-rated distance vision was correlated with higher prevalence of URE (p(trend)<0.001). In a multivariate logistic regression model adjusting for age, gender, retirement status, educational level and social class, independent significant associations with URE were increasing age (p(trend)<0.001) and having hypermetropic or myopic refractive error. Wearing distance spectacles was inversely associated with URE (OR 0.34, 95% CI 0.21 to 0.55, p<0.001). There were 3063 people (69.2%) who wore spectacles/contact lenses for distance vision. Spectacle wear differed according to type of refractive error (p<0.001), and use rose with increasing severity of refractive error (p(trend)<0.001). Conclusion Although refractive error is common, the prevalence of URE was found to be low in this population reflecting a low prevalence of PVA<0.3.