Retinal Vessel Caliber and Peripheral Neuropathy in Diabetic Participants

Abstract

Retinal vascular caliber changes predict diabetic microvascular complications such as retinopathy, and nephropathy. However, the association between retinal vasculature and peripheral neuropathy is not well studied. We evaluated the association between retinal vascular caliber and peripheral neuropathy in a multi-ethnic Asian population with diabetes (n = 423) in Singapore. Retinal arteriolar and venular caliber was measured from digital retinal photographs and summarized as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent. Peripheral neuropathy was defined from neurothesiometer or monofilament sensory testing. Larger CRAE was positively associated with peripheral neuropathy independent of age, sex, ethnicity, current smoking, alcohol consumption, body mass index, total cholesterol, systolic blood pressure, and duration of diabetes. The multivariable odds ratio (OR) [95% confidence interval (CI)] of peripheral neuropathy was 2.81 (1.38-5.73) comparing highest vs. lower three quartiles of CRAE. This association was consistently present in analyses stratified by age, sex and ethnicity. Retinal venular caliber was not associated with peripheral neuropathy. These data suggest that larger retinal arteriolar diameters are associated with peripheral neuropathy independent of major risk factors.