Purpose:
To compare retinal vessel calibre in persons with and without diabetes.
Methods:
Participants were recruited from the population-based cross-sectional 6th survey of the Tromsø Study, northern Norway, conducted in 2007/2008. All subjects with self-reported diabetes and retinal photos of sufficient quality (164 women and 153 men), and 638 controls matched by age and gender were included. Retinal vessel calibre was measured computer-assisted on digital retinal images of one eye and summarized as central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) by using Knudtson’s revised formulae. Retinal vessel calibres were compared using multivariable linear regression analysis, correcting for age, gender and the opposite vessel equivalent.
Results:
Mean age was 66 years (SD 8,3, range 46-87 years). Median duration of diabetes (reported by 71% of the participants) was 6 years in both women (SD 7,4, range 0-42 years) and men (SD 9,0, range 0-64 years). Mean CRAE in controls was 140.2 µm (women 140.6 µm, men 139.9 µm) and in patients with diabetes 141.0 (women 141.4 µm, men 140.6 µm). Mean CRVE in controls was 210.8 µm (women 210.4 µm, men 211.2 µm) and in patients with diabetes 209.6 (women 207.4 µm, men 211.9 µm). After adjustment for age and CRAE, diabetes was significantly associated with a reduction of CRVE in women (β-coefficient -3.62 µm, 95% CI -6.73 – -0.50, p=0.02), but not in men (β-coefficient 0.11 µm, 95% CI -3.15 – 3.37, p=0.9). Diabetes was not significantly associated with CRAE neither in women nor men.
Conclusions:
Our results indicate that diabetes is associated with reduced retinal venular calibre in women, but not in men.