Prevalence and Risk Factors of Refractive Errors and Effective Spectacle Coverage in Emiratis and Non-Emiratis Aged 40 Years or Older: the Dubai Eye Health Survey

Abstract

Purpose: The aim was to investigate the prevalence and risk factors of refractive errors (REs) and the effective spectacle coverage in Emiratis and non-Emiratis in Dubai. Design: The Dubai Eye Health Survey was a population-based cross-sectional study of participants aged 40 years or older. Methods: Distance and near visual acuity (VA), and noncycloplegic automated refraction were tested according to a standardized protocol. Distance VA was tested using the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart at 3 m and near VA was measured using the near vision logMAR chart at 40 cm under ambient lighting. Myopia was defined as spherical equivalent of refraction of less than –0.50 diopters (D), and hypermetropia as spherical equivalent of more than +0.50 D. Astigmatism was defined as cylinder power of 0.5 D or greater. Effective spectacle coverage for distance vision was computed as met need/(met need+unmet need+under-met need)×100%. Multivariable logistic regression models were used to examine associations between sociodemographic factors and RE. Results: The authors included 892 participants (446 Emiratis and 446 non-Emiratis) in the analysis. The prevalence of hypermetropia was 20.4% [95% confidence interval (CI): 16.8%–24.4%] in Emiratis and 20.6% (95% CI: 20.0%–24.7%) in non-Emiratis. The prevalence of myopia and high myopia was 27.4% (95% CI: 23.3%–31.7%) and 1.8% (95% CI: 0.8%–3.5%) in Emiratis, and 19.5% (95% CI: 15.9%–23.5%) and 0.9% (95% CI: 0.2%–2.3%) in non-Emiratis, respectively. High education (P=0.02) and not currently working (P=0.002) were risk factors of myopia in non-Emiratis only. The prevalence of astigmatism was 7.4% (95% CI: 5.1%–10.2%) in Emiratis and 1.6% (95% CI: 0.6%–3.2%) in non-Emiratis. This prevalence was higher in individuals aged over 60 years (P<0.001) and men (P=0.014) among Emiratis. The prevalence of anisometropia and uncorrected presbyopia was 11.4% (95% CI: 8.6%–14.8%) and 0.7% (95% CI: 0.1%–2.0%) in Emiratis, and 9.2% (95% CI: 6.7%–12.3%) and 0.4% (95% CI: 0.05%–1.6%) in non-Emiratis, respectively. The effective spectacle coverage was 62.3% (95% CI: 54.0%–70.6%) and 69% (95% CI: 60.5%–77.5%) in Emiratis and non-Emiratis, respectively. Conclusions: A high proportion of Emiratis and non-Emiratis was affected by RE without optimal effective spectacle coverage, highlighting the imperativeness of intervention to alleviate the burden. The findings may help facilitate evidence-based policymaking concerning the delivery of eye care services and allocation of medical resources in Dubai.