糖化血红蛋白与糖尿病视网膜病变的关系：北京社区糖尿病研究 18

目的 探讨糖化血红蛋白（HbA1c）与糖尿病视网膜病变（DR）的关系及其诊断阈值。设计 以社区人群为基础的横断面研究。研究对象 北京社区糖尿病研究中2642例20~80岁已确诊的2型糖尿病患者，其中2007例（76.0％）受试者（1199例女性）参与研究，平均年龄（64.1±9.0）岁。方法 全体参与医师经过专门培训，按照统一要求调查并填写调查表，同时对患者进行体格检查及相关的实验室检查，HbA1c用美国伯乐公司高压液相仪测定，并对所有患者用45°免散瞳彩色眼底照相机留取后极部眼底照片一张。DR的严重程度参照Airlie House分级法。采用 ROC 曲线分析HbA1c诊断DR的最佳阈值。主要指标 HbA1c在DR中的诊断阈值（敏感性、特异性、AUC）。结果 本人群中DR患病率为（24.7±1.0）％（95％CI，22.8~26.6）。在二元逻辑回归分析中，DR的出现与较高的HbA1c浓度（OR=1.23；95％CI，1.14~1.33）有关，随着HbA1c增高，DR患病率呈上升趋势。当HbA1c≥6.5%时，诊断DR的ROC曲线下面积最大（59.2%），且敏感性（75.1%）和特异性（43.4%）高。在二元逻辑回归分析中，DR还与其他方面有关：较轻的年龄（OR=0.97；95％CI，0.95~0.98）、较长的糖尿病病程（OR=1.10；95％CI，1.08~1.12）、较高的收缩压（OR=1.01；95％CI，1.01~1.02）、较低的体重指数（OR=0.95；95％CI，0.92~0.98）和升高的血尿素氮浓度（OR=1.01；95％CI，1.00~1.01）。结论 当糖化血红蛋白≥6.5%时与糖尿病视网膜病变显著相关，提示糖化血红蛋白为6.5%或许可以作为筛查糖尿病视网膜病变的阈值。（眼科，2016，25： 321-325）

Influence of glycosylated hemoglobin on diabetic retinopathy--Beijing Community Diabetes Study 18

Objective We aimed to provide updated data for the relation between Glycosylated hemoglobin(HbA1c) and diabetic retinopathy(DR), and to estimate cut-off of HbA1c for DR. Design Community-based cross-sectional investigation. Participants The community health care center-based study included 2642 subjects with diabetes mellitus and an age of 20 years to 80 years, who were recruited from 15 community health centers in urban Beijing. Of 2642 eligible patients, 2007 (76.0%) subjects (1199 women) with a mean age of 64.1±9.0 years participated. Methods A cluster sampling technique was used to identify and include patients with type 2 diabetes mellitus from urban Beijing communities. HbA1c was measured by the liquid chromatography technique. Fundus photographs were graded using the modified Airlie House classification system. The area under the receiver operating characteristic (ROC) curve was used to determine the diagnostic value of HbA1c between the study groups. Main Outcome Measures Sensitivity, specificity, area under the curve(AUC). Results The overall prevalence of DR was (24.7±1.0)% (95% confidence interval [CI], 22.8~26.6). In binary logistic regression analysis, presence of DR was associated with higher concentration of HbA1c (OR=1.23; 95%CI, 1.14~1.33). With the increase of HbA1c, the prevalence of DR showed an increasing trend. The Receiver Operating Characteristic analysis showed that the cut-off value of 6.5% had 75.1% sensitivity and 43.4% specificity with 59.2% maximum. In binary logistic regression analysis, presence of DR was also associated with younger age (OR=0.97; 95%CI, 0.95~0.98), longer duration of diabetes (OR=1.10; 95%CI, 1.08~1.12), higher systolic blood pressure (OR=1.01; 95%CI, 1.01~1.02), lower body mass index (OR=0.95; 95%CI, 0.92~0.98), and elevated blood urea concentration (OR=1.01; 95%CI, 1.00~1.01). Conclusions HbA1c value ≥6.5% is significantly related with DR and PDR. In a screening program, the cut-off value of HbA1c≥6.5% may provide a maximum yield of DR. (Ophthalmol CHN, 2016, 25: 321-325)