Study On The Detection Value Of HbA1c In Type 2 Diabetic Kidney Disease

Background:Diabetic kidney disease（DKD）is one of the common and serious microvascular complications of diabetes mellitus（DM）,and also one of the main causes of death and disability of diabetic patients.In recent years,the prevalence of diabetes in China has been increasing year by year,and so has the prevalence of DKD.Patients with DKD also have an increased risk of developing cardiovascular disease,end-stage renal disease（ESRD）,and even death.When the body is in a state of hyperglycemia for a long time,the risk of complicated microvascular diseases and macrovascular diseases,including diabetic kidney disease and retinopathy,will be greatly increased.Therefore,the effective control of blood glucose in diabetic patients and the early detection of abnormal blood glucose levels are very important for the early screening and diagnosis of DKD and the determination of intervention measures to prevent or slow down the progress of DKD.Objective:This paper studies the detection value of HbA1c in type 2 diabetic kidney disease by exploring the relationship between HbA1c and glomerular filtration rate（GFR）and the difference of HbA1c in the accuracy of reflecting blood glucose control in DM patients and DKD patients.Methods:From January 2019 to June 2020,122 patients with type 2 diabetic kidney disease without renal replacement therapy and 122 patients with type 2 diabetic mellitus alone admitted to the Second Department of the First Hospital of Jilin University during the same period were retrospectively studied as study group（DKD group）and control group（DM group）.Collection of two groups of patients with gender,age,height,weight,duration of diabetes,such as general clinical data,fasting glucose,HbA1c,serum creatinine,urea,cystatin C,triglycerides,total cholesterol,high density lipoprotein,low density lipoprotein,laboratory indexes such as renal ultrasound,imaging results such as fundus examination,and whether the data,such as high blood pressure,diabetes complications.Body mass index was calculated by the formula,and serum creatinine was substituted into CKD-EPI formula to obtain GFR.IBM SPSS 20.0 software was used for data analysis and processing of the above statistical data.For normal distribution or similar to normal distribution of measurement data to mean+/-standard deviation（（?）±s）said,mean comparison between the two groups using the t test.Measurement data of skewness distribution were expressed as median（lower quartile-upper quartile）.Comparison between two groups was performed by Mann-Whitney U test,and comparison between multiple groups was performed by Kruskal-Wallis H test.Enumeration data were expressed as frequency（constituent ratio）,and the chi-square test was used for comparison between groups.Spearman rank correlation was used to analyze the correlation between the two variables.P<0.05 was considered statistically significant.Results:（1）Among the 122 DKD patients enrolled,12（9.8%）,33（27%）,18（14.8%）,18（14.8%）,and 41（33.6%）patients were enrolled in chronic kidney disease stage 1 to 5,respectively,according to the KDOQI guidelines formulated by the American Kidney Foundation,11（9.01%）patients were enrolled in middle CKD3 stage 3A,and 7（5.74%）patients were enrolled in stage 3B.Abnormal results in 122 patients with DKD renal ultrasound（double kidney size,shape,structure,or reduce the blood flow）of 54 cases（44.3%）,hypertension disease in 63 patients（51.6%）,merging in 84 patients（68.9%）of diabetic retinopathy,retinopathy merged in 84 patients of lower limb arteriosclerosis in 6 cases（7.1%）,merging in 2 cases of diabetic peripheral neuropathy（2.4%）,the merger of the diabetic foot in 2 cases（2.4%）.（2）Compared with DM group,DKD group had higher age,duration of diabetes,serum creatinine,urea and cystatin C,and lower fasting blood glucose,glycated hemoglobin and glomerular filtration rate,with statistical significance（P<0.05）.There were no significant differences in gender,body mass index,triglycerides,total cholesterol,high-density lipoprotein,low-density lipoprotein and other indexes between the two groups（P>0.05）.（3）Spearman rank correlation was used to conduct correlation analysis,and the results showed that HbA1c was positively correlated with GFR,fasting blood glucose and TG（P<0.05）,and negatively correlated with serum creatinine,urea and cystatin C（P<0.05）.GFR was negatively correlated with urea,cystatin C and diabetes course（P<0.05）,but had no significant correlation with TG（P>0.05）.（4）Patients in DKD group and DM group were divided into H₁（HbA1c<6.5%）,H₂（6.5≤HbA1c<8%）and H₃（HbA1c≥8%）groups according to the different levels of HbA1c,and the differences of glomerular filtration rate（GFR）levels among the three groups were analyzed and compared.The results showed that the GFR value of DKD group was lower than that of DM group at different HbA1c levels,and the difference of GFR between the two groups was statistically significant（P<0.05）.Kruskal-Wallis H test was used to make pairwise comparison between DKD group and DM group.The comparison results showed that there was no significant difference in GFR among the three groups in DM group（P>0.05）.There were statistically significant differences in GFR among the three groups in DKD group（P>0.05）,and with the increase of HbA1c level in the group,the GFR of the three groups increased successively,H₁<H₂<H₃.The GFR of the H₁and H₂groups was compared with that of the H₃group,respectively,and the difference was statistically significant（P<0.05）.The GFR of the H₁group and the H₂group showed no statistically significant difference（P>0.05）.（5）When fasting blood glucose>6.1 mmol/L,the positive rate of HbA1c≥6.5%in the DKD group was 70.37%,which was lower than that of the DM group（96.46%）.The difference of positive rate between the two groups was statistically significant（P<0.05）.Conclusions:（1）The level of HbA1c was positively correlated with glomerular filtration rate in diabetic kidney disease.（2）HbA1c can reflect early renal injury to a certain extent and assist in the diagnosis of early DKD.（3）There are differences in the accuracy of HbA1c in reflecting the blood glucose control of diabetes mellitus and diabetic kidney disease.The accuracy of HbA1c in reflecting the blood glucose of DKD patients in the late stage of renal disease is not accurate and the reliability is low.