PURPOSE: To examine the association between retinal vessel diameters and retinopathy in participants with and without type 2 diabetes in a Danish population-based cohort.

METHODS: The study included 878 persons aged 30 to 60 years from the Inter99 Eye Study. Retinopathy was defined as a presence of one or more retinal hemorrhages or one or more microaneurysms. Vessel diameters were expressed as central retinal artery equivalent diameter (CRAE) and central retinal vein equivalent diameter (CRVE). Multiple linear regression analyses were performed.

RESULTS: Among participants with diabetes, CRAE was 6.3 µm (CI 95%: 1.0 to 11.6, p = 0.020) wider and CRVE was 7.9 µm (CI 95%: 0.7 to 15.2, p = 0.030) wider in those with retinopathy compared to those without retinopathy, after adjusting for age, gender, HbA1c, blood pressure, smoking, serum total and HDL cholesterol. In all participants, CRAE increased with presence of retinopathy (p = 0.005) and with smoking (p = 0.001), and CRAE decreased with hypertension (p < 0.001), high HDL cholesterol (p = 0.016) and age (p < 0.001). Central retinal vein equivalent diameter increased with presence of retinopathy (p = 0.022) and with smoking (p < 0.001), and decreased with higher HDL cholesterol (p < 0.001) and age (p = 0.015). Female gender was associated with wider CRVE (p = 0.029).

CONCLUSIONS: Wider retinal vessel diameters were associated with the presence of retinopathy in participants with diabetes, but not in participants without diabetes. The associations between retinal vessel diameters and known retinopathy risk factors were confirmed. These results suggest that information obtained by non-invasive imaging of the interior of the eye can contribute to a better understanding of systemic disease processes.