42-PUB: Income-Related Inequalities in Self-Reported Vision Problems among U.S. Adults, 1999–2018

Introduction & Objective: Research has shown that the prevalence of vision problems is higher among U.S. adults with low income. Recent changes in income-related inequalities (IRI) in the prevalence of vision problems are unknown. We aim to examine trends in IRI in vision problems and to identify the relative contribution of determining factors.

Methods: We estimated annual IRI in vision problems in 1999−2018 among US adults aged ≥18 years using data from the National Health Interview Survey. Vision problems are defined as an affirmative response to the question: “Do you have trouble seeing, even when wearing glasses or contact lenses?”. We used the concentration index (CI) to measure IRI and quantified the extent to which the prevalence of vision problems concentrates in lower income versus higher income groups. We used the Wagstaff decomposition method to decompose CI into contributors. We examined trends from 1999−2018 in vision problems inequality and contributors to those trends over time.

Results: Between 1999−2018, the CIs were below 0, signifying that vision problems were more concentrated among individuals with lower incomes. The degree of IRI in vision problems increased from 1999−2018 (annual percent change=0.6, p=0.03). IRI in vision problems was greater among adults aged 45-64 years than other age groups. Decomposition analysis revealed that poverty-to-income ratio and public health insurance coverage were the largest contributors to IRI in vision problems, with smaller contributions made by smoking, physical inactivity, and female sex. Among all variables, non-White race/ethnicity, lower physical activity, and poverty-to-income ratio were the main factors explaining trends in vision problems inequality over time.

Conclusion: Self-reported vision problems were more prevalent in low-income populations, and IRI widened over time. The sustained growth in income inequality may lead to a larger population burden of vision problems.