Visual impairment and mortality in patients with type 2 diabetes

Area of Science:

• Ophthalmology
• Diabetology
• Public Health

Background:

• Type 2 diabetes affects millions globally, with visual complications being a significant concern.
• Visual acuity impairment is a known complication of diabetes, but its independent impact on mortality requires further investigation.

Purpose of the Study:

• To determine if visual acuity impairment at the time of type 2 diabetes diagnosis independently predicts all-cause and diabetes-related mortality.
• To assess the association between visual acuity and mortality over a 19-year follow-up period.

Main Methods:

• A 19-year follow-up study of 1241 patients (aged ≥40) newly diagnosed with type 2 diabetes.
• Visual acuity (logMAR) measured by ophthalmologists at diagnosis and 6 years later.
• Multivariable Cox regression models adjusted for confounders and censored for mediators (fractures/trauma).

Main Results:

• Visual impairment at diagnosis strongly predicted all-cause mortality within 6 years (HR: 1.51).
• Reduced logMAR acuity was also associated with fractures/trauma (HR: 1.59).
• After censoring for fractures/trauma, visual acuity remained an independent predictor of all-cause mortality (HR: 1.68); no association with diabetes-related mortality was found.

Conclusions:

• Visual acuity impairment at type 2 diabetes diagnosis is an independent short-term predictor of all-cause mortality.
• Visual acuity measured later (6 years post-diagnosis) did not predict long-term mortality, suggesting confounding by comorbidity.