Color vision impairment in type 2 diabetes assessed by the D‐15d test and the Cambridge Colour Test

Abstract

Color vision impairment emerges at early stages of diabetes mellitus type 2 (DM2) and may precede diabetic retinopathy or the appearance of vascular alterations in the retina. The aim of the present study was to compare the evaluation of the color vision with two different tests - the Lanthony desaturated D-15d test (a traditional color arrangement test), and the Cambridge Colour Test (CCT) (a computerized color discrimination test) - in patients diagnosed with DM2 without clinical signs of diabetic retinopathy (DR), and in sex- and age-matched control groups. Both color tests revealed statistically significant differences between the controls and the worst eyes of the DM2 patients. In addition, the degree of color vision impairment diagnosed by both tests correlated with the disease duration. The D-15d outcomes indicated solely tritan losses. In comparison, CCT outcomes revealed diffuse losses in color discrimination: 13.3% for best eyes and 29% for worst eyes. In addition, elevation of tritan thresholds in the DM2 patients, as detected by the Trivector subtest of the CCT, was found to correlate with the level of glycated hemoglobin. Outcomes of both tests confirm that subclinical losses of color vision are present in DM2 patients at an early stage of the disease, prior to signs of retinopathy. Considering the advantages of the CCT test compared to the D-15d test, further studies should attempt to verify and/or improve the efficiency of the CCT test.

Color vision changes in normal aging

“…Such losses can reflect reduced inner retinal and choroidal blood circulation (Hirata and Nishiwaki, 2006), changes in the retinal pigment epithelium (Panda-Jonas et al, 1996), damage to photoreceptors, and accelerated loss of RGC bodies and axons as reported in Alzheimer's disease (Curcio and Drucker, 1993) or glaucoma (Marvasti et al, 2013;Tatham et al, 2014). Less well-defined, neural and vascular changes can cause vision degradation and loss of chromatic sensitivity in patients with systemic disease such as diabetes (Bronson-Castain et al, 2012;Calkins, 2013;Feitosa-Santana et al 2010;Harrison et al, 2012;Tam et al, 2012). Accurate measurements of RG and YB color thresholds coupled with reliable age-related, upper-threshold limits are of great clinical interest as the means to detect the earliest signs of disease.…”

Further Observations on Visual Perception: The Influence of Pathologies Upon the Absorption of Light and Emission of Bioluminescence

“…The loss of blue-yellow colour vision has been shown to be an indicator of the onset of type 1 diabetes mellitus [112,[114][115][116][117][118][119][120][121][122]. The loss of other colours in the visual spectrum are associated with coronary heart disease [123], migraine [124][125][126] and may also be implicated in the diagnosis of other heart conditions [127][128][129].…”

Development of a new test to diagnose and determine the degree of color vision disorders

“…Diversos testes para avaliar a sensibilidade cromática têm sido desenvolvidos ao longo dos anos: Ishihara, Hardy-Rand-Rittler, City University, Farnsworth-Munsell 100-Hue e o Farnsworth D15. Dentre eles, o Cambridge Colour Test já tem sido aplicado em estudos científicos utilizando-se do computador 10,11,12 . Apesar da diversidade de testes existentes, nenhum é considerado completo, pois apresentam limitações no que se refere à degradação e modificação dos tons pelo tempo, à variabilidade de tons em função da luz, além da dificuldade de instruir o paciente quanto ao uso 12 .…”