Aims To evaluate retinal arterial wall thickness (WT) using high-resolution retinal imaging in patients with type 2 diabetes and assess its correlation with risk factors for arteriosclerosis.

Methods Outer diameter, inner diameter and WT of the retinal artery were measured using adaptive optics scanning laser ophthalmoscopy in 28 patients with type 2 diabetes without clinically apparent diabetic retinopathy and normal volunteers. Laboratory values and intima-media thickness (IMT) in the common carotid artery were measured.

Results Retinal arterial WT was significantly greater in patients with type 2 diabetes than in controls (p=0.02). There was a significant correlation of retinal artery WT with IMT in patients with diabetes (r=0.40, p=0.04). WT in patients with diabetes was positively correlated with haemoglobin A1c (HbA1c) (r=0.49, p=0.001), total cholesterol (r=0.47, p=0.002) and low-density lipoprotein cholesterol (r=0.47, p=0.003).

Conclusions Microvasuclar thickness was greater in patients with diabetes than in controls. Furthermore, WT was positively correlated with HbA1c, total cholesterol and low-density lipoprotein cholesterol levels and IMT in the diabetic group. These results suggest that retinal artery wall measurements can be potential surrogate markers of early diabetic microangiopathy.