Optical coherence tomography distribution patterns of diabetic macular edema and its correlations with diabetic retinopathy stages and systemic factors

Abstract

Objective To investigate the distribution patterns of diabetic macular edema (DME) based on optical coherence tomography (OCT), and explore its correlation with diabetic retinopathy (DR) stages and systemic factors. Methods A total of 135 patients (242 eyes) with type 2 diabetes were included in this retrospective study. There were 75 males (138 eyes) and 60 females (104 eyes), the ages were from 29 to 83 years, with an average age of (58.8±11.1) years. The general information such as height, weight, smoking history and blood glucose [such as glycosylated hemoglobin (HbA1c)], blood pressure, blood lipid, 24 hours urine protein and other examinations were collected. The diagnosis of DR and DME were made, and the staging of DR and typing of DME were performed based on fundus color imaging and OCT. DR were divided into mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR and proliferative DR (PDR). DME were categorized into 4 types including sponge-like retinal swelling (SME), cystoid macular edema (CME), serous retinal detachment (SRD) and posterior hyaloid traction (PHT). The correlation between DME types and DR staging were analyzed by χ2 test and Fisher exact test. Multivariate logistic regression analysis was used to analyze the correlation between DME types and systemic factors. Results In 242 DR eyes the proportions of mild, moderate, severe NPDR and PDR were 30.99%, 32.64%, 23.14% and 13.23%, respectively. There were 199 eyes (82.23%) with DME. There were statistically significant differences in the proportion of DME in different stages of DR (χ2=21.077, P<0.01). In the 199 eyes with DME, There were 165 eyes (68.18%) of SME, 22 eyes (9.09%) of CME, 7 eyes (2.89%) of SRD and 5 eyes (2.07%) of PHT. The distribution of DME patterns in different stages of DR was statistically significant (χ2=156.273, P<0.01). Logistic regression analysis showed that the duration of diabetes, HbA1c and macroalbuminuria were independent risk factors for DME [odds ratio (OR)= 1.090, 1.510, 4.123; P<0.05], and were also independent for SME (OR=1.092, 1.445, 3.942; P<0.05); HbA1c was an independent risk factor for SRD (OR=2.337, P<0.05). Conclusions There are differences in the distribution of different DME types in each stage of DR. The duration of diabetes, HbA1c and macroalbuminuria were independent risk factors for DME and SME, and macroalbuminuria and HbA1c for CME and SRD. Key words: Macular edema/diagnosis; Risk factors; Diabetic retinopathy/diagnosis; Tomography, optical coherence