The Correlation Of Abdomen Intracavity Fat And Insulin Resistance In Patients With Coronary Heart Disease

Objective: Obesity, particularly visceral obesity, is closed associatedwith the increased risks of cardiovascular morbidity and mortality. Uneven ofobesity and different distribution mode of body fat had particular influence tometabolic disease, cardiovascular disease.Research indicates that, it is thevisceral fat, but not the subcutaneous fat, which was closed associated withinsulin resistance(IR) and other cardiovascular risk factors. Some otherresearches showed that, fats in various region had different risk factors tometabolic disease.Visceral fat is the physiologically-active components ofbody adipose tissue,which secretes vasoactive vascular inflammatory factors.And it may be the only pathogenic adipose tissue which has extremely closerelationship with obesity-comorbidities,and is the independent risk factor ofIR of type2diabetes.The measurement of abdominal obesity also developedfrom some simple anthropometric measurements,such as waist cireumference(WC) and waist-hip ratio(WHpR), to some modern measurements with preciseinstrument, such as bioelectrical impedance analysis(BIA), ultrasonography(US),dual-energy X-ray absorptiometry (DEXA), computed tomography(CT),magnetic resonance imaging(MRI)and so on. The above methods havetheir own advantages and disadvantages. WC and WHpR are simple,and arewidely used,but they can't predict abdominal fat distribution quantitatively.DEXA and underwater weighing(UWW) can measure the percentage of bodyfat, but can not measure the local body fat. US and BIA had a bettercorrelation with CT. But US are subject to considerable between-examiner andwithin-examiner variation.While BIA has not been widely used in china. TheCT and MRI are the golden standard methods of quantitatively judging thedistribution of visceral fat.They can value the fat distribution of wholeabdomen only through a single scan, with high accuracy and good reproduc- ibility.In coronary heart disease (CHD) patient with or without diabetes, IR is aindependent risk factor for CHD and is closely correlated with the severity ofcoronary artery stenosis with unstable angina. Epidemiology data shows thatIR could have exist before exist before diabetes and cardiovascular disease,and is also the common pathophysiologic base of diabetes mellitus,hypertension, dyslipidemia, and cardiovascular disease risk factors. Therefore,it is quite meaningful to assess IR in the early stage of cardiovascular disease.At present,in the methods of evaluation of IR, homeostasis model assessment-insulin resistance (HOMA-IR) is not only technically simple and inexpensive,but also is closely correlated with the euglycemic clamp which is the goldenstandard methods of evaluation of IR.There were not so many correlational Studies about visceral fat and IR innon-diabetic CHD patients at present. In this research, the body fat parameterswere gotten through measuring patients' weight, WC, hip circumference (HC),WHpR, body mass index(BMI) and so on. The body fat distribution was gotby measuring visceral fat area(VFA) and subcutaneous fat area(SFA) throughslice CT scan at L4-L5. And HOMA-IR was used to evaluated IR.FinallyLinear multiple variable regression was used to analyze the relationshipbetween body fat distribution, index and HOMA-IR in non-diabetic patientswith CHD. So that we could provide evidence for risk estimating, prophylaxisand treatment of non-diabetic CHD patients in clinical works.Methods:80patients who were treated in the Cardiology Department ofHebei Medical University Second Hospital from December1st,2010toOctober1st,2011,and whose symptoms were in line with diagnostic criteria forCHD of WHO in1997were chosen as the sample group.48of them weremen,and others were women.Their age,weight,height,WC,HC were beenrecorded when they were checked into the hospital,together with the Fastingplasma glucose (FPG) and the Fasting serum insulin (FINS) detection fromulnar vein and the abdominal CT check on an empty stomach.All of thepatients were in line with the selection criteria.And theBMI,WHtR,WHpR, HOMA-IR were calculated. IS was also calculated using the HOMA IR Modelusing the formula:FINS(μIU/ml) X FPG(mmol/l)/22.5,and we defined thevalue greater than2.5as an IR state and the value less than2.5as aninsulin-sensitive(IS) state.All statistical analyses were performed using the SPSS13.0programpackage.Measurement data were expressed as the mean value±standarddeviation.Measurement data between two groups were compared by ttest.Analysis of risk factors was performed by multiple linear regressionanalysis.A P value of less than0.05was considered to be statisticallysignificant.Result: There were no significant difference in age between IS group andIR group (P＞0.05). The VFA,SFA, WHtR, WC,WHpR and BMI wassignificantly higher in IR group than IS group(P＜0.05).And the result ofmultiple linear regression analysis indicated that there was linear regressionbetween VFA,SFA,WC,WHtR,WHpR,BMI and lnHOMA-IR,and therespective standardized regression coefficient were0.488(P＜0.001),0.183(P＜0.001),0.171(P＜0.001),0.102(P=0.001),0.075(P＜0.001),0.012(P=0.015).Conclusion: There was no statistical implication for the difference of agebetween IS group and IR group.However,there was significant difference onVFA,SFA,WHtR,WC,WHpR and BMI between the two groups,and the IRgroup had much higher value for the six parameters than the IS group.If weused lnHOMA-IR as the dependent variable,meanwhile VFA,SFA,WHtR,WC,WHpR,BMI as independent variable,and after multiple linear regressionanalysis,we should get the conclusion that VFA,SFA,WHtR,WC,WHpR,BMIhad impacted on lnHOMA-IR,and VFA which reflected the adipose tissuedistribution of internal organs had played the most significant role.