Impact Of Obesity On Longitudinal Changes To Left Ventricular Structure And Function In Patients With Type 2 Diabetes Mellitus

Background:Type 2 diabetes mellitus(T2DM)is a common disease in clinical,and the cardiovascular complications are the main course of death.The early detection of abnormalities of cardiac structure and function is particularly important for patients with diabetes.In addition,the early detection and effective control of the clinical risk factors on the changes of cardiac structure and function can improve the quality of life and survival rate in patients with T2DM.Recently,the prevalence of obesity is steadily increased and obesity is one of the important risk factors to diabetes,and it also a risk factor that contribute to cardiovascular complications in patients with T2DM.Present study have demonstrated weight loss can reduce the health problem which resulted from obesity,and improve the clinical prognosis of these patients.Recently,most of the studies about the cardiac structure and function in patients with T2DM are cross-sectional studies,while the follow-up study is limited.The impact of obesity on short-term cardiac structural and functional changes in patients with T2DM has not been evaluated.Objective:To explore the clinical risk factors associated with cardiac structure and function abnormalities in patients with T2DM.And to explore the natural progression of left ventricular structure and function in patients with T2DM during a short-term follow-up and the impact of BMI on longitudinal cardiac structural and functional changes in patients with T2DM.Methods:(1)The study total enrolled 314 T2DM patients(mean age,62±11years;male,162 cases,female,152 cases),and enrolled 118 healthy controls(mean age,60±8 years;male,63 cases,female,55 cases).(2)All patients were performed echocardiographic examination,echocardiography parameters were measured including inter-ventricular septal dimension at end-diastole(IVSd),left ventricular posterior wall thickness at end-diastole(LVPWd),left ventricular ejection fraction(LVEF),peak early transmitral flow velocity(E),peak late transmitral flow velocity(A),peak early diastolic velocity of septal(e septal)and lateral(e lateral)mitral annular.Left ventricular mass index(LVMi),E/A ratio,average E/e ratio were calculated.(3)A total of 274 patients with T2DM were follow up after 12 to 48 months.Patients were divided into 3 groups according to baseline BMI:normal weight(BMI<23kg/m~2),overweight(23?BMI<27.5kg/m~2)and obesity(BMI?27.5kg/m~2).(4)274 patients were performed echocardiography at baseline and follow-up,echocardiography parameters were measured including IVSd,LVPWd,LVEF,E,A,e septal and e lateral.LVMi,E/A ratio and average E/e ratio were calculated.Left ventricular structure and diastolic function were classified according to the guideline of American society of echocardiography(ASE).Results:1.To explore the impact of T2DM on patients’cardiac structure and function and the correlative risk factors.(1)Compared with control group,patients with T2DM had higher IVSd,LVPWd and LVMi(P<0.01,P<0.05,P<0.05,respectively).A and average E/e were significantly higher than control group(P<0.01,P<0.05).On the contrary,e septal and e lateral were lower than control group(P<0.01,P<0.05,respectively).(2)Multiple liner regression indicated that age,systolic blood pressure(SBP)and BMI were independently associated with LVMi;age and SBP were independently associated with e septal;age was independently associated with e lateral;age,SBP and diastolic blood pressure(DBP)were independently associated with average E/e ratio.2.Impact of obesity on longitudinal changes to left ventricular structure and function in patients with type 2 diabetes.(1)The median follow-up was 24months(from 12 to 48 months).The entire corhort showed a significantly increased in left ventricular wall thickness and LVMi,and the prevalence of left ventricular concentric hypertrophy was increased from 19.6%to 27.3%.Further,LVEF was significantly decreased and diastolic dysfunction had deteriorated at follow-up assessment.The prevalence of diastolic dysfunction was increased from 35.0%to 42.8%.(2)The prevalence of normal weight,overweight and obesity was 22.3%,44.9%and 32.8%,respectively.LVMi was increased and LVEF decreased in these three groups,but the changed of LVMi and LVEF in obesity group was more significantly than normal weight and overweight groups(both P<0.05).Multiple liner regression demonstrated that BMI was the independent risk factor to the change of LVMi(β=0.21,P<0.01)and LVEF(β=-0.16,P<0.01).Conclusion:(1)The change of cardiac structure and diastolic function in patients with T2DM were significant.(2)Age and SBP were independently associated with cardiac structure and diastolic function in patients with T2DM.(3)BMI was the independent risk factor to the change of left ventricular structure and function.