Unilateral Visual Impairment and Increased Mortality: The UK Biobank Cohort Study

The purpose of this study was to investigate the association between the full spectrum of visual acuity categories and risks of all-cause, cardiovascular disease (CVD)-related, cancer-related mortality in the UK Biobank study.

A total of 131,468 participants (aged 40-79 years) with visual acuity measurement from the UK Biobank prospective cohort were included. Visual acuities of both eyes were used to assign each participant into one of the following groups: bilateral normal, unilateral near normal, bilateral near normal, unilateral visual impairment (VI), mild VI, and low vision. Cox proportional hazards multivariable regression models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the risks of all-cause, CVD-related, and cancer-related mortality.

Over a median follow-up of 13.49 years, a total of 9372 deaths were recorded, including 4682 cancer-related deaths and 1926 CVD-related deaths. Compared with the bilateral normal group, participants with decreased visual acuity had increased risks of all-cause and CVD-related mortality with dose-response-type gradients, but no elevated risk of cancer-related mortality was observed. Decreased unilateral visual acuity but not bilateral near normal vision was associated with increased risks for all-cause and CVD-related mortality. For all-cause and CVD-related mortality, the adjusted HRs were 1.17 (95% CI = 1.09-1.25) and 1.24 (95% CI = 1.07-1.44) for the unilateral near normal group, and 1.20 (95% CI = 1.14-1.27) and 1.26 (95% CI = 1.12-1.42) for the unilateral VI group.

Decreased unilateral visual acuity was associated with increased all-cause and CVD-related mortality risks among participants without VI in the UK Biobank.

Achieving bilateral vision balance may contribute to reducing the mortality risk of individuals with decreased unilateral visual acuity.