Evaluation Of The Therapeutic Effect Of Liraglutide On Epicardial Adipose Tissue In Patients With Obese Type 2 Diabetes Mellitus By Echocardiography

Objective:Liraglutide,as a new type of drug to improve blood glucose,has been gradually used for the treatment of patients with type 2 diabetes mellitus(T2DM).The effect of the drug is not only significant to regulate blood glucose,but also can apparently reduce weight of patients with T2DM.The purpose of this study was to evaluate the therapeutic effect of liraglutide on epicardial adipose tissue(EAT)in patients with obese T2DM by transthoracic two-dimensional echocardiography.Methods:According to diagnostic criteria for diabetes mellitus issued by American Diabetes Association in 2016,thirty-six patients,diagnosed with obese T2DM in the second affiliated Hospital of Dalian Medical University,from March 2016 to August2019,were recruited for the study.In our study,all selected patients must meet the following inclusion criteria:newly diagnosed as T2DM,body mass index(BMI)>25kg/m~2,waist circumference(WC)levels for female and male separately were>80cm and>90cm,and hemoglobin A1c(Hb A1c)levels>6.5%.Exclusion criteria are as follows:patients with liraglutide taboos,such as allergy and severe gastrointestinal reactions;women who were pregnant or breastfeeding;subjects with heart,hepatic,renal,and other important organic injuries or lesions;thyroid diseases,Cushing syndrome and other endocrine diseases;T2DM with acute complications(such as diabetic ketoacidosis)or severe infection,and severe benign and malignant tumors,etc.Appropriate diet guidance and exercise management were carried out for all participants during the study period.The patients were given a single dose of liraglutide by subcutaneous injection every day to control the level of blood glucose.Liraglutide was administered with initial dosage of 0.6mg once daily,and added to 1.2mg once daily after1 week.If blood glucose levels in some patients were poorly controlled at the dosage of1.2mg once daily,and they could tolerate more medication without performing serious adverse reactions(allergies,severe nausea and vomiting),we would consider subsequent increments to 1.8mg once daily.All patients were treated with liraglutide monotherapy for continuous 3 months.Sex,age,anthropometrics and blood biochemical characteristics of all participants were collected and recorded before treatment with liraglutide.Anthropometrics included weight,height,hip circumference(HC)and WC,and BMI was calculated.Biochemical characteristics included fasting blood glucose(FBG),Hb1Ac,C-peptide,fasting insulin(FINS),homeostasis model assessment of insulin resistance(HOMA-IR),total cholesterol(TC),high-density lipoprotein cholesterol(HDL-C),triglyceride(TG),spartate aminotransferases(AST),alanine aminotransferases(ALT),low-density lipoprotein cholesterol(LDL-C)and urinary albumin.Conventional transthoracic two-dimensional echocardiography,using a GE Vivid E9 Color Doppler echocardiography scanner equipped with M5S probe(1.7～3.3MHz),was performed to quantitatively analyze the thickness of EAT in all patients.After 3 months of continuous treatment,the above indicators were detected repeatedly and their changes were analyzed for all the patients.Results:1.Biochemical characteristicsCompared with pre-study,FBG,Hb A1c,C-peptide,insulin,AST,ALT,urinary albumin,TC and HOMA-IR all obviously varied(all p<0.05).Although TG,HDL-C and LDL-C levels were improved,the changes were not statistically significant(all p>0.05).2.Anthropometric characteristicsAfter three months of treatment,weight,BMI,WC and HC performed highlysignificant decreases,the changes were statistically significant(all p<0.05).3.EAT thicknessEAT thickness was(9.14±2.39)mm and(6.42±1.48)mm,respectively before and after treatment,the difference is statistically significant(p=0.001).After Pearson correlation analysis,we found that there were obvious correlation between the variation of EAT thickness and the variations of WC,the variations of HC,the variations of BMI(r was0.878、0.899 and 0.846,respectively).Conclusion:1.Liraglutide not only could effectively improve blood glucose of patients with obese T2DM,but also helps to reduce EAT accumulation.2.Transthoracic two-dimensional echocardiography is an effective and convenient method for quantitative analysis of EAT thickness in obese patients with T2DM.