Visual impairment among adolescents attending rural and urban schools in Peru

Visual acuity plays an important role in adolescent learning, and visual impairment may go unnoticed, affecting reading, attention, and academic performance. This study compared the visual acuity of secondary school students from a rural and an urban school in Peru's Amazonas region. In this cross-sectional comparative study, 243 students selected through stratified probability sampling were assessed monocularly with the Snellen chart, and overall visual acuity was defined by the worse eye. Associations were evaluated with Pearson's chi-square and Kruskal–Wallis tests; the rural–urban difference was expressed as prevalence ratios (PR) with 95% confidence intervals (CI), stratified by sex and age group with the Mantel-Haenszel method, and adjusted for age and sex through Poisson regression with robust variance. The results showed that 66.7% of students had normal vision, whereas 24.7% had mild visual impairment, 7.0% had moderate visual impairment, and 1.6% had severe visual impairment. The prevalence of visual impairment was 33.3% (95% CI: 27.7–39.5) based on the worse eye and 24.7% (95% CI: 19.7–30.5) based on the better eye, as recommended by the WHO, and was higher in the urban school with both criteria ( p = 0.003 and p = 0.042, respectively). Visual acuity was associated with school location ( χ 2 = 10.0058; p = 0.0185), grade level ( χ 2 = 26.5902; p = 0.0088), and age (H = 9.2753; p = 0.0258). The prevalence of visual impairment was 38.8% in the urban school and 18.5% in the rural school (PR = 2.10; 95% CI: 1.22–3.61). In the multivariable model, school location was the only factor independently associated with visual impairment (adjusted PR = 2.09; 95% CI: 1.20–3.61), whereas age and sex were not. These findings point to an unmet eye-health need in this population that warrants comprehensive eye examinations to establish its causes and the most appropriate interventions.