Analysis Of The Effect Of HbA1c Variability On Type 2 Diabetic Retinopathy

BackgroundDiabetes is a systemic disease that progresses relatively slowly.In the past decade,the global prevalence of diabetes is still high and rising.The prevalence and number of diabetes patients in China are among the highest in the world,and the situation is not optimistic.Type 2 diabetes is the main disease in China.With the increase of the number of patients with diabetes,the number of patients with chronic complications of diabetes is also increasing,which has a serious negative impact on both individuals and society.Diabetic retinopathy(DR)is common in clinical practice,and is the leading cause of visual impairment and even blindness in diabetic patients.The pathogenesis and cause of DR are still unclear,so we need to explore the factors affecting DR.A number of previous studies have confirmed that glycosylated hemoglobin(HbAlc)is an important parameter to evaluate whether blood glucose is well controlled or not,and can be used as one of the main predictors of diabetes and its complications.However,the evaluation of HbAlc alone has some limitations.It is currently believed that one of the major risk factors for the occurrence of DR is the variability of blood glucose control,including "glucose variability" and "HbA1c variability".HbA1c variability is thought to predict the occurrence and development of DR in type 1 diabetes mellitus(T1DM).However,there is no clear evidence that HbAlc variability affects DR in type 2 diabetes mellitus(T2DM).In addition,the influencing factors of HbAlc variability are not clear.Therefore,this study discusses this issue.ObjectiveTo investigate the influencing factors of HbAlc variability in type 2 diabetes mellitus.To evaluate the effect of HbAlc variability on DR in patients with type 2 diabetes mellitus.MethodsA total of 206 patients with type 2 diabetes who visited the Department of Endocrinology and Metabolism of the First Affiliated Hospital of Zhengzhou University from January 2019 to March 2021 were selected as subjects.Their medical history and clinical data were collected and analyzed,and follow-up was conducted.The patients were divided into two groups according to whether there was retinopathy or not:96 patients without retinopathy(NDR)and 110 patients with retinopathy(DR).HbAlc-Mean and HbA1c-SD were calculated according to the recorded HbAlc values of each study object.Based on both results,the patients were divided into four groups:Q1 group(HbAlc-Mean<7.0%,HbAlc-SD<0.89%);Q2 group(HbAlcMean<7.0%,HbAlc-SD≥0.89%);Q3 group(HbAlc-Mean≥7.0%,HbAlc-SD<0.89%);Q4 group(HbAlc-Mean≥7.0%,HbAlc-SD≥0.89%).ROC curve was drawn to evaluate the value of HbA1c variability in early diagnosis of DR.ResultsLogistic regression analysis showed that HbAlc-SD was independent risk factors for DR in patients with type 2 diabetes.Stratification showed that Q4 group had the highest risk of DR(OR=2.793,P<0.05).Multiple linear regression results showed that insulin treatment significantly increased HbA1c variability(P<0.01),while age,gender,course of disease,alcohol consumption and other factors had no statistical significance on HbAlc variability(P>0.05).ROC curve analysis showed that the area under the variability curve(AUC)of HbAlc was 0.590(95%CI:0.510-0.670).The optimal critical value of HbAlc variability for the diagnosis of DR was 0.625(the sensitivity:0.673,and the specificity:0.573).Conclusion1.HbA1c variability is an independent risk factor for DR in patients with type 2 diabetes.2.The optimal critical value of Hba1C-SD for early diagnosis of DR was 0.625.