United States Population Disparities in Ophthalmic Care: Blindness and Visual Impairment in the IRIS® Registry (Intelligent Research in Sight)

Abstract

Purpose: To evaluate associations of patient characteristics with United States eye care use and likelihood of blindness.

Design: Retrospective observational study.

Participants: Patients (19 546 016) with 2018 visual acuity (VA) records in the American Academy of Ophthalmology's IRIS® Registry (Intelligent Research in Sight).

Methods: Legal blindness (20/200 or worse) and visual impairment (VI; worse than 20/40) were identified from corrected distance acuity in the better-seeing eye and stratified by patient characteristics. Multivariable logistic regressions evaluated associations with blindness and VI. Blindness was mapped by state and compared with population characteristics. Eye care use was analyzed by comparing population demographics with United States Census estimates and proportional demographic representation among blind patients versus a nationally representative US population sample (National Health and Nutritional Examination Survey [NHANES]).

Main outcome measures: Prevalence and odds ratios for VI and blindness; proportional representation in the IRIS® Registry, Census, and NHANES by patient demographics.

Results: Visual impairment was present in 6.98% (n = 1 364 935) and blindness in 0.98% (n = 190 817) of IRIS patients. Adjusted odds of blindness were highest among patients ≥ 85 years old (odds ratio [OR], 11.85; 95% confidence interval [CI], 10.33-13.59 vs. those 0-17 years old). Blindness also was associated positively with rural location and Medicaid, Medicare, or no insurance vs. commercial insurance. Hispanic (OR, 1.59; 95% CI, 1.46-1.74) and Black (OR, 1.73; 95% CI, 1.63-1.84) patients showed a higher odds of blindness versus White non-Hispanic patients. Proportional representation in IRIS Registry relative to the Census was higher for White than Hispanic (2- to 4-fold) or Black (11%-85%) patients (P < 0.001). Blindness overall was less prevalent in NHANES than IRIS Registry; however, prevalence in adults aged 60+ was lowest among Black participants in the NHANES (0.54%) and second highest among comparable Black adults in IRIS (1.57%).

Conclusions: Legal blindness from low VA was present in 0.98% of IRIS patients and associated with rural location, public or no insurance, and older age. Compared with US Census estimates, minorities may be underrepresented among ophthalmology patients, and compared with NHANES population estimates, Black individuals may be overrepresented among blind IRIS Registry patients. These findings provide a snapshot of US ophthalmic care and highlight the need for initiatives to address disparities in use and blindness.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Keywords: Blindness; Health care disparities; IRIS Registry.

Figure 1:. Visual Acuity Distribution in 2018 American Academy of Ophthalmology IRIS^® Registry (Intelligent Research In Sight)¹

IRIS = Intelligent Research In Sight clinical data registry ¹ Visual acuity reported in logMAR, determined based on each patients’ better-seeing eye, using the mean of all visual acuity measurements (excluding uncorrected and near visual acuity) for each eye in 2018, and selecting the better of the two eyes’ mean visual acuity. Modified logMAR and Snellen equivalents presented in Supplemental Table 17.

Figure 2:. 2018 American Academy of Ophthalmology IRIS^® Registry (Intelligent Research In Sight) Prevalence and Odds Ratios for Blindness by US State

A. Prevalence of Blindness per State (% of IRIS population) B. Adjusted Odds of Blindness per US State^1,2 IRIS = Intelligent Research In Sight clinical data registry ¹ Logistic regression models adjusted for age, sex, race/ethnicity, insurance, and smoking. Geographic region and population density were not adjusted for due to collinearity. ² N=13,443,951 after excluding patients with missing sex, smoking, geographical, age, race, density, or insurance data. Sex had 33,806 (<1%), smoking had 867,712 (<5%), geographical region had 3,896,141 (approximately 20%), age had 40,332 (<1%), race had 0 (0%), density had 4,587,142 (approximately 23.5%), and insurance had 0 (0%) missing.