A 5-year prospective study of type 2 diabetes patients in Shanghai Xinjing Community 3.The regression and promoting factors of diabetic retinopathy and diabetic macular edema in Chinese type 2 diabetes patients

Abstract

Background Long-term study on type 2 diabetes discovered that some patients with diabetic retinopathy (DR) or diabetic macular edema (DME) appear regression of lesions without invasive ocular intervention but only systemic medication.These mechanisms remain unclear. Objective This study was to survey the regression rate and relevant factors of DR and DME in type 2 diabetic patients. Methods A prospectively observational study was performed.Totally 778 patients who met the inclusion criteria participated in this consecutive 5-year survey.The demographic information of the patients was collected, and the systemic and ophthalmological examinations were carried out, and the fundus photography was identified by 2 doctors by blind method.DR was graded into non-, mild-, moderate-, severe-nonproliferation DR and proliferative DR based on international clinical classification, and DME was graded into non-, mild-, moderate-and severe-DME.DR improvement and DME regression were served as the outcome variables and defined as the grading of DR or DME in lateral eyes lowering by at least 1 grade and without development of DR or DME in fellow eyes.The influences of age, gender, education level, diabetes onset age, diabetes course, obesity and serum creatinine, triacylglycerol, total cholesterol and glycosylated hemoglobin levels were evaluated by Logistic regression analysis. Results Four hundred and fifty-six patients appeared DR in the initial examination, of which 139 patients appeared regression of DR severity with the regression rate of 30.48%.Both low blood glucose level and low serum creatinine level at initial examination were independent risk factors associated with DR regression (blood glucose level: odds ratio(OR)=0.53, 95% confidence interval [CI]: 0.45-0.63, P<0.01; serum creatinine level: OR=0.98, 95%CI: 0.97-0.99, P<0.01). One hundred and fifty-eight patients were found to have DME at the initial examination, of which 20 had a regression of DME severity throughout the follow-up duration, with the regression rate 12.66%.High baseline blood glucose level was found to be the only independent risk factor associated with DME regression (OR=1.47, 95%CI: 1.14-1.91, P<0.01). Conclusions Effective control of blood glucose and serum creatinine levels is a favorable factor for the regression of DR, and the rapid drop of blood glucose level is beneficial to the regression of DME. Key words: Diabetes, type 2/complications; Retinopathy, diabetic; Macular edema, diabetic