Estimating the prevalence of visual impairment in the Netherlands, with forecasts up to 2050: a meta-analysis of national databases

<h2>Summary</h2><h3>Background</h3> Current prevalence estimates of visual impairment (i.e., low vision and blindness) in the Netherlands are lacking. Based on representative databases, we aimed to estimate the prevalence of visual impairment among Dutch adults and to forecast estimates to 2050. <h3>Methods</h3> We undertook a meta-analysis of national databases. Databases were primarily identified through expert consultation and included when representative of the Dutch population and containing recent (≥2010) data on vision (visual acuity <6/18, self-reported visual functioning, or relevant International Classification of Primary Care [ICPC] codes). We classified self-reported visual functioning according to four definitions: A) only near vision difficulties; B) only distance vision difficulties; C) both near and distance vision difficulties; D) any vision difficulties (combining A–C). Population-based prevalences were calculated and pooled using four meta-analyses, including heterogeneity assessment and subgroup analyses. Age-effects were modelled using logistic mixed-effects models. <h3>Findings</h3> We included eight databases with data collected data between 2010 and 2024, accounting for 1,814,716 individuals (894,541 males and 920,175 females). Five databases were prospective population-based cohort studies, two were periodically administered cross-sectional health surveys, and one contained registrations from general practices. Five databases had self-reported data on visual functioning, two had data on best-corrected distance visual acuity, and one included ICPC codes. There was substantial heterogeneity with assessment method as moderator (i.e., self-reported vs. visual acuity vs. ICPC; I² statistic >98%, p < 0.0001). The pooled prevalence of visual impairment was 0.28% (95% CI: 0.11–0.73) for visual acuity (2 databases), whereas it was 0.51% (95% CI: 0.50–0.52) for ICPC (1 database). The prevalence for self-report (five databases) depended on the definition. For only near vision difficulties (A), prevalence was 1.81% (95% CI: 1.01–3.21); for only distance vision difficulties (B), prevalence was 0.63% (95% CI: 0.50–0.80); for both near and vision difficulties (C), prevalence was 0.51% (95% CI: 0.31–0.83); and for any vision difficulties (D), prevalence was 3.21% (95% CI: 2.15–4.77). After applying age-specific and assessment-specific prevalence estimates to projected population structures, we estimate that 39,100–406,400 Dutch adults have visual impairment in 2025, and this is estimated to increase to 48,800–489,100 by 2050 owing to population growth and ageing, depending on definitions. <h3>Interpretation</h3> Despite inherent limitations (including databases mostly containing self-reported data on visual functioning) and substantial uncertainty in estimates, this study provides population-level estimates of visual impairment in the Netherlands. Although these estimates span a wide range of values, they reveal trends and plausible uncertainty intervals, illustrating the potential magnitude of the current and future burden of visual impairment. <h3>Funding</h3> Dutch Eye Foundation (Oogfonds).