The Study On The Correlation Among Basal Levels Of GIP,Diabetic Microvascular Complications And Other Influence Factor

Objective1.To investigate the correlation between the levels of basal glucose-dependent insulinotropic polypeptide(GIP)and microvascular complications in type 2 diabetes mellitus(T2DM).2.To explore the impacting factors of basal GIP levels in T2 DM.MethodA cross-sectional study was performed in 295 T2 DM patients who were hospitalized in our endocrine ward during the period from July 1,2019 to December 31,2019.Firstly,the levels of basal GIP were measured using enzyme-linked immunosorbent assays(ELISA)methods.Next,fundus were examined using retinal camera by an ophthalmologist to further assess the severity of it.Subsequently,we collected basic information and clinical parameters such as gender,age,duration of T2 DM,the levels of microalbuminuria and urinary creatinine,glycosylated hemoglobin A1c(Hb A1c),fasting plasma glucose(FPG),total cholesterol(TC),triglyceride(TG)and uric acid(UA)from the medical record system of our hospital.Finally,statistical methods were used to analyze the correlation between the levels of basic GIP levels and microvascular complications,and multiple stepwise regression analysis was performed to evaluate the independent relationship among the levels of basic GIP,diabetic microangiopathy and other clinical parameters.Results1.The morbidity of diabetic retinopathy(DR)were significantly higher in low levels of basal GIP group compared with those in high levels of basal GIP group in T2DM(46.26% versus 31.08%,P=0.007)and the levels of basal GIP were higher in T2 DM patients without DR than those with DR(440.99pg/ml versus 405.90pg/ml,P=0.019).2.The levels of basal GIP of T2 DM patients without both DR and diabetic nephropathy(DN)were higher in contrast to those with both DR and DN(441.54pg/ml versus 403.85pg/ml,P=0.046)and those with DR along(441.54pg/ml versus 417.57pg/ml,P=0.052).3.Morbidity of DR was independently and negatively correlated with the levels of basal GIP in T2DM(β=-0.279,95%CI:-0.512～-0.047,P=0.019).4.No differences were observed on fasting serum GIP between non-proliferative diabetic retinopathy(NPDR)and proliferative diabetic retinopathy(PDR)(P=0.971).5.We did not find any association between the levels of basal GIP and morbidity of DN.ConclusionsOur finding concluded that prevalence of DR was independently and negatively correlated with fasting serum GIP in T2 DM,indicating that elevated levels of basal GIP were protective factors for DR and low levels of basal GIP were associated with a significantly increased risk of DR in T2 DM,which mechanism and clinical significance need to be further discussed.