# Risk of visual impairment according to the comorbidity of systemic and ocular diseases

## TL;DR

This study examines how systemic and eye diseases like hypertension, diabetes, and glaucoma affect the risk of visual impairment.

## Contribution

The study identifies how combinations of diseases influence visual impairment risk, including a surprising negative correlation for glaucoma in some groups.

## Key findings

- Hypertension, diabetes, and diabetic retinopathy significantly increase the risk of visual impairment.
- Glaucoma increases VI risk when combined with diabetic retinopathy but shows a negative correlation in other groups.
- Periodic eye exams for glaucoma may help prevent VI caused by other diseases.

## Abstract

To investigate the risk of visual impairment (VI) based on the presence or absence of four diseases: hypertension (HTN), diabetes mellitus (DM), glaucoma, and diabetic retinopathy (DR).

This retrospective population-based study included 1,000,000 randomly selected participants from the National Health Checkup Program database between 2015 and 2016. VI was defined as a presenting visual acuity ≤ 0.5 in the better eye. The participants were divided into 12 groups according to the presence or absence of disease. Adjusting for age and sex, the risk of VI in each disease group was analyzed and compared with the others.

Among the 1,000,000 participants, 88,931 (8.89%) had VI. The odds ratios (ORs) of age, male sex, HTN, DM, glaucoma, and DR for VI were 1.06 (95% CI, 1.05–1.06), 0.52 (95% CI, 0.52–0.53), 1.11 (95% CI, 1.09–1.13), 1.07 (95% CI, 1.05–1.09), 0.92 (95% CI, 0.90–0.74), and 1.29 (95% CI, 1.25–1.34), respectively (all P < 0.001). The group with HTN, DM, glaucoma, and DR had the highest OR of 1.98 (P < 0.001) compared to the healthy group. HTN, DM, and DR were positively correlated with VI in all groups. Glaucoma was positively correlated in the group with DM and DR and in the group with HTN, DM, and DR (ORs 1.18, 1.11, all P < 0.05); however, it demonstrated a negative correlation in the other groups (ORs 0.85–0.93, all P < 0.05).

HTN, DM, and DR, either alone or in combination, increase the risk of VI. Glaucoma also increases the risk when combined with DR; however, it has a negative correlation with VI in the absence of DR. Periodic ophthalmologic examinations for glaucoma, which primarily affects the peripheral visual field and not central visual acuity, might help prevent VI caused by other diseases.