Einstein International Journal Organization(EIJO)

Abstract

Background: Diabetes mellitus is a chronic metabolic disorder associated with multiple ocular complications, including diabetic retinopathy. Increasing evidence suggests that functional retinal abnormalities may occur before clinically detectable structural changes. Among these, impairment of color vision has been reported as an early indicator of retinal neurodegeneration in diabetic patients. Evaluating color vision may therefore provide a simple and non-invasive method for detecting early retinal dysfunction.

Objective: To evaluate color vision changes in patients with diabetes mellitus and to assess their association with the presence and severity of diabetic retinopathy.

Methods: This cross-sectional observational study was conducted in the Department of Ophthalmology at RKDF Medical College Hospital and Research Centre, Bhopal, India, for a duration of 4 months. A total of 40 patients diagnosed with Type 1 or Type 2 diabetes mellitus aged ≥18 years were included. All participants underwent detailed ophthalmic evaluation including best corrected visual acuity, slit-lamp examination, intraocular pressure measurement, and dilated fundus examination. Diabetic retinopathy was graded according to the Early Treatment Diabetic Retinopathy Study (ETDRS) classification. Color vision was assessed using Ishihara pseudoisochromatic plates under standardized illumination. Data were analyzed using SPSS software. Descriptive statistics, chi-square test, and logistic regression analysis were performed, and p < 0.05 was considered statistically significant.

Results: Among the 40 participants, 22 (55%) had normal color vision and 18 (45%) demonstrated color vision defects. Color vision abnormalities were more frequently observed in patients with moderate and severe non-proliferative diabetic retinopathy and proliferative diabetic retinopathy. Chi-square analysis showed no statistically significant association between retinopathy grade and color vision defect (p = 0.8172). Logistic regression suggested a positive association between duration of diabetes and likelihood of color vision impairment. Receiver operating characteristic (ROC) analysis showed an area under the curve (AUC) of 0.888, indicating good diagnostic performance of color vision testing.

Conclusion: Color vision abnormalities are relatively common in diabetic patients and tend to increase with the severity and duration of diabetes. Although statistical significance was limited by small sample size, color vision testing may serve as a useful adjunctive tool for detecting early retinal dysfunction in diabetic individuals.

Keywords: Diabetes Mellitus, Color Vision, Ishihara Test, Diabetic Retinopathy, Retinal Neurodegeneration, Visual Function.

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