Incidence and predictors of vision loss complicating type 2 diabetes: The Fremantle Diabetes Study Phase II

Background and purpose: Although diabetes is associated with multiple ocular complications, there are limited data on the incidence and predictors of visual acuity (VA) loss in type 2 diabetes. The aim of this study was to determine the 4-year cumulative incidence of visual impairment and blindness, and the predictors of vision loss, in a representative community-based cohort.

Methods: The longitudinal Fremantle Diabetes Study Phase II recruited 1551 participants with type 2 diabetes between 2008 and 2011. Participants attended biennial face-to-face assessments including VA measurement. Multivariable logistic regression was used to determine the predictors of vision loss (defined as a decrease in VA by >10 letters at the Year 4 assessment), excluding those with visual impairment (VA >6/19 and ≤6/48) and blindness (VA >6/48) at baseline.

Results: 882 participants with normal/near normal vision at baseline had VA data at Year 4 available. During a median [interquartile range] 4.1 [4.0-4.4] years of follow-up, the cumulative incidences of visual impairment and vision loss were 0.9% (n = 8) and 2.9% (n = 26), respectively. No participants developed blindness and 1.9% (n = 17) improved their VA. Multivariable logistic regression showed baseline smoking (OR: 3.17 (95% CI: 1.15-8.76)), prior severe hypoglycemia (5.59 (1.32-23.61)) and urinary albumin:creatinine ratio (uACR) (1.42 (1.09-1.84) for an increase of 1 in ln(uACR)) had higher odds of vision loss during follow-up.

Conclusions: Smoking cessation and management strategies that avoid severe hypoglycemia and preserve kidney function may potentially prevent vision loss in people with type 2 diabetes.