Colour assessment in patients at risk of developing diabetes

Abstract

AbstractDiabetes has frequently been linked to loss of colour vision. A recent study has shown that over 70% of diabetics have significant loss of both Yellow/Blue (YB) and Red/Green (RG) colour vision (https://doi.org/10.1111/j.1755-3768.2012.f073.x), in the absence of clinical signs of retinopathy. This study also showed poor correlation between the severity of RG or YB loss and parameters such as duration of diabetes, age, HbA1c, body mass index, visual acuity or central retinal thickness. The aim of this study was to investigate whether clinically ‘normal’ subjects, who have been identified as being at ‘risk’ of developing diabetes, show significant changes in colour vision and rod and cone sensitivities.A ‘high‐risk’ group (n = 62) and subjects diagnosed with diabetes (n = 23) were recruited from a healthcare centre that offers diagnostic and screening services, including vision assessment. The inclusion criteria for ‘high‐risk’ group required 3 or more recognised risk factors for diabetes (e.g., age >45, HbA1C >5.7, high blood pressure, smoking history, high BMI, family history of diabetes, FPG levels >100 mg/dl). All subjects had full ophthalmic assessment and their RG and YB colour vision, Functional Contrast Sensitivity, Visual Acuity and Rod‐ and Cone‐mediated flicker sensitivity were measured using the Advanced Vision and Optometric Tests (AVOT) developed at City University (www.avot/city.ac.uk).Consistent with previous findings, the diabetic group show significant loss of both RG and YB colour vision. They also have higher thresholds for rod‐ and cone‐mediated vision. Surprisingly, the ‘high‐risk’ subject group who do not meet the clinical criteria for early diabetes also show significant loss of colour and rod and cone sensitivity. These findings suggest that accurate assessment of colour vision and rod and cone mediated thresholds can be used as early biomarkers in in prediabetic screening.