长期强化控制血糖对新发糖尿病视网膜病变的影响

目的 探讨长期强化控制血糖对新发糖尿病视网膜病变（DR）的影响.方法 将2002年在我院门诊就诊的49例2型糖尿病患者,随机分为强化降糖组（24例）和标准降糖组（25例）,进行为期5年的分组血糖管理,强化降糖组的糖化血红蛋白（HbA1c）控制目标为≤6.5％,标准降糖组进行一般降糖治疗,HbA1 c控制目标为≤7.0％.由同一位眼科医生定期对患者进行眼底检查并做眼底照相,评估有无新发DR（微动脉瘤、眼底出血、黄斑水肿、糖尿病性失明、视力下降2行及以上、视网膜激光光凝治疗）.在分组血糖控制5年后,两组再进行开放式血糖控制2年.之后再次对两组患者进行眼底检查和眼底照相,分析比较长期强化与标准血糖控制对新发糖尿病视网膜病变的后续作用.结果 ①分组血糖控制中,强化降糖组的HbA1c水平从第2年开始明显低于标准降糖组[（6.3±0.6）％与（7.1±2.0）％,t=2.09,P＜0.05],并一直维持了4年.②分组血糖控制5年间,强化降糖组无新发眼底出血和糖尿病性失明;发生微动脉瘤、黄斑水肿的例次数较标准降糖组少（分别为5例次比10例次,1例次比3例次）,视网膜激光光凝治疗及视力下降2行及以上的例次数较标准降糖组明显减少（分别为4例次比23例次,15例次比25例次,Z=-4.459,P＜0.05）.③开放式血糖控制后半年,强化降糖组患者血糖水平上升达到与原标准降糖组相似的水平[HbA1c分别为（7.2±1.1）％比（7.3±1.3）％,=0.25,P=0.806],并维持到末次随访时（2009年11月）.④开放式血糖控制2年期间,两组均无黄斑水肿、糖尿病性失明的发生.强化降糖组新发微动脉瘤、眼底出血、视网膜激光光凝治疗、视力下降2行及以上较标准降糖组明显减少（3例次比14例次,1例次比7例次,2例次比4例次,3例次比11例次,合计9例次比36例次,x2=4.719,P＜0.05）.结论 对2型糖尿病患者进行5年严格强化血糖控制,对降低DR发生风险的“后遗效应”可持续到开放式血糖控制后2年.

Long-term effect of intensive glucose control on diabetic retinopathy in type 2 diabetes patients

Objective To observe the effect of long-term intensive glucose control therapy on diabetic retinopathy in outpatients with type 2 diabetes mellitus.Methods Forty-nine patients with type 2 diabetes mellitus were randomly assigned to participate in the trial from 2002 to 2007,receiving either intensive （24 cases） or standard glucose control （25 cases）.The patients were examined by the same ophthalmologists to identify any new diabetic retinopathy （DR）.After 5 years of intensive glucose control,all of the patients were asked to attend our clinic every 6 months,but no attempts were made to maintain their previously assigned therapies.Hemoglobin A1c （HbA1 c） was measured regularly.In November of 2009,a retinal examination was carried out by the same ophthalmologist who worked in the trial.The visual acuity,lens,vitreous body and fundus were examined after pupil dilation to identify diabetic retinopathy （DR）.Fundus fluorescein angiography and retinal laser photocoagulation were carried out when necessary.Results In the second year after enrollment in the trail,the median HbA1c level of the intensive-therapy group was significantly lower than that of the standard-therapy group [（6.3 ± 0.6） ％ vs.（7.2 ± 1.2） ％,t =2.09,P ＜ 0.05],and was maintained in a controlled level throughout the following 4 years.During the post-trial monitoring,no new case of of macula edema or diabetic associated blindness occurred in either intensive or standard-therapy group,the whole occurrence of micro-aneurysms,fundus hemorrhage,as well as those who needed retinal laser photocoagnlation and lowering in visual acuity in intensive-therapy group was lower than that in the standard-therapy group （3 vs.14,1 vs.7,2 vs.4,3 vs.11,respectively ;9 vs.36,totally,x2 =4.719,P ＜ 0.05）.During the first post-trial monitoring,there was no difference in median HbAlc level between intensive-therapy group and standard-therapy group [（7.2 ± 1.1） ％ vs.（7.3 ± 1.3） ％,t =0.25,P =0.806],which was sustained in the following years.In the trail,no new case of fundus hemorrhage or diabetic associated blindness occurred in intensive-therapy group during the five-year period of therapy.Number of new episodes of micro-aneurysm,macula edema were less in intensive-therapy group than that in standard-therapy group,number of new episodes of lowering in visual acuity,and those who needed retinal laser photocoagnlation,were significantly less in intensive-therapy group than that in standardtherapy group（15 vs.25,4 vs.23,Z =-4.459,P ＜ 0.05） during five-year follow-up.Conclusions The benefit of reduced incidence of diabetic retinopathy in intensive glucose can be maintained because of the legacy effect.