Study of visual acuity and contrast sensitivity in diabetic patients with and without non-proliferative diabetic retinopathy.

Purpose: To analyze high and low contrast visual acuity and contrast sensitivity in diabetic patients without clinically significant macular edema associated or not with non-proliferative diabetic retinopathy.

Methods: Cross-sectional study of 368 eyes of 368 patients classified into three groups: a) disease-free patients, b) patients with diabetes mellitus (DM) without diabetic retinopathy, c) DM patients with non-proliferative diabetic retinopathy. All patients underwent a complete ophthalmological examination that included high and low contrast visual acuity with 1.25%, 2.5% and 5% contrast chart and Pelli-Robson type contrast sensitivity test.

Results: We observed no statistically significant differences regarding age, intraocular pressure, duration of diabetes or high contrast visual acuity. The eyes of patients with non-proliferative diabetic retinopathy had worse contrast sensitivity (p = 0.03, in both cases) and low contrast visual acuity at 1.5% (p = 0.03 and p = 0.01), 2.5% (p = 0.01, in both cases) and 5% (p = 0.02 and p = 0.04) than patients free of disease or without diabetic retinopathy.

Conclusions: Analysis of contrast sensitivity and low contrast visual acuity could be considered as markers of visual function impairment in the eyes of patients with non-proliferative diabetic retinopathy.