Study On Factors Influencing Type2Diabetic Retinopathy

Objective: With developing and improving of people's living standardsin China, diabetes and its complications has emerged as a major threat tohuman health. Most diabetic patients are complicated with varying degrees ofdiabetic retinopathy(DR), which is one of the most common microangiopathiccomplications of diabetes. The occurrence and development of DR is not onlyassociated with metabolic syndrome (MS) that is comprised of a variety ofmetabolic diseases such as hypertension, obesity, hyperglycemia anddyslipidemia, but also associated with an increasing level of retinol bindingprotein4(RBP4).In this study, RBP4was compared with other DR influencing factors inT2DM patients with and without DR, including blood pressure (BP), durationof diabetes, glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose(FPG), Fasting insulin (FINS), homeostasis model assessment-insulinresistance (HOMA-IR), triglyceride (TG), totalcholesterol (TC), high-densitylipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C),visceral fat area (VA) and subcutaneous fat area (SA).By analyzingrelevant intensity and linear relationship between RBP4and these factors, thestudy was to expound the possible pathogenesis of DR, thus provided aprobable indicator for the early dignosis, prevention and treatment in DR.Methods:87cases of T2DM patients who were hospitalized atdepartment of Endocrinology, the Third Affiliated Hospital of Hebei MedicalUniversity were recruited from September2010to September2011, of which49were males and38were females. The diagnosis of DM was based on thecriteria of the WHO(1999). According to the six-level staging system ofretinopathy adopted by China's Third National Ocular Fundus DiseaseDiscussion in1985and by Chinese Ophthalmological Society in1987,87cases were divided into DR group and NDR group based on with or without DR. Clinical data of each patient was recorded in detail,including SEX, Age,Height, Weight, calculated body mass index (BMI), systolic blood pressure(SBP), diastolic blood pressure (DBP), medical history, duration ofdiabetes(DUR), cigarettes or alcohol addict, as well as other medical historysuch as coronary heart disease and hypertension. Venous blood samples werecollected to measure TG, TC, HDL-C, LDL-C, FPG and FINS. HbA1c wasmeasured using a DCA2000analyzer (Bayer Medical, Germany) andHOMA-IR was obtained by calculation. RBP4was determined by ELISAmethod. VA and SA were measured by computed tomography (CT). Mydriaticfundus photography was used as a method to identify diabetic retinopathy.Quantitative data were expressed as means±SD. Associations between thegroups were examined using the analysis of student's t-test or χ2test.Correlation analysis was used for univariate analysis, and multiple regressionanalysis for multivariate analysis. Statistical analyses were done by SPSSSoftware (V13.0, SPSS Inc., USA). P values <0.05were consideredstatistically significant.Results:1There were no significant difference in the weight, height and BMI betweenthe two groups (P>0.05). Compared with the NDR group, the factors of DUR,Age, SBP and DBP were significantly increased in the DR group (P<0.01).2The levels of TC, TG, FPG, lnHOMA-IR and HbA1c were significantlyhigher in the DR group than that of the NDR group (P<0.01), whereas therewere no differences in LDL-C and FINS between the two groups (P>0.05). Inthe NDR group, the HDL-C level was higher than that of the DR group(P<0.01) while in the DR group, the RBP4level was significantly higher thanthat of the NDR group (P<0.01).3VA and SA of DR group were significantly higher than that of the NDRgroup (P<0.01).4The Simple linear correlation analysis showed that, DR was positivelycorrelated with DUR, Age, SBP, DBP, TC, TG, RBP4, FPG, HbA1c,lnHOMA-IR, VA, SA and negatively correlated with HDL-C(P<0.01). Using DR as the dependent variable, multiple regression analysis showed that DUR,RBP4and HDL-C were the independent influencing factors of DR.5The Simple linear correlation analysis showed that, RBP4was positivelycorrelated with DUR, Age, SBP, DBP, lnHOMA-IR, TC, TG, FPG, HbA1c, VA,SA and negatively correlated with HDL-C(P<0.05). Using RBP4as thedependent variable, multiple regression analysis showed that DUR andHDL-C were the independent influencing factors of RBP4.Conclusion:1The risk of DR was increasing as the duration of disease extended.Hypertension, hyperglycemia and dyslipidemia may be risk factors of DR,while HDL-C was a protective factor of DR.2RBP4and insulin resistance(IR)may contribute to the occurrence andprogress of DR. RBP4may be a risk factor for the prediction of DR.