Macular Choroidal Thickness May Be the Earliest Determiner to Detect the Onset of Diabetic Retinopathy in Patients with Prediabetes: A Prospective and Comparative Study

Abstract

Purpose: To evaluate the macular and peripapillary choroidal thickness and retinal volume in prediabetes.Material and Methods: This prospective comparative study included 53 patients with prediabetes and 53 age- and sex-matched healthy subjects. Only right eyes were selected. Choroidal thicknesses (CT) and retinal volume were measured by optical coherence tomography. Macular CT was measured at the seven points including macular center, 1, 2, and 3 mm distances along the temporal and nasal scans. Peripapillary CT was measured at the eight points of the optic disk area. Systemic and laboratory findings of the subjects were also recorded.Results: There were no significant differences in blood pressures, ocular findings including intraocular pressure, visual acuity, and refractive powers, and macular volumes between the two groups (p > 0.005). Macular and peripapillary CT at all measuring points, body mass index (BMI), fasting blood glucose (FBG), hemoglobinA1C, and lipid profile were significantly higher in prediabetic patients (p < 0.05). There was a significant positive correlation between all points of macular choroidal thicknesses with BMI, FBG, and hemoglobin A1C (p < 0.05).Conclusion: Prediabetic factors including impaired FBG, increased hemoglobinA1C, and BMI are independent risk factors for increase in choroidal thickness. Increased macular choroidal thickness may be the earliest determiner to detect the onset of diabetic retinopathy in prediabetes.