Impact Of Insulin Resisitance On The Risk Factors Of Coronary Artery Disease And Coronary Artery Lesion Severity

Objective: In order to demonstrate the impacts of insulin resisitance, this research isto discuss the relationship between common risk factors of coronary heart disease,characteristics of injured coronary artery and insulin resisitance which may be the riskfactor for coronary heart disease further for prevention and treatment of coronaryheart disease.Methods: By retrospective case analysis, we studied 273 coronary artery diseasecases admitted in cardiology department and operated on coronary angiography fromApr.1.2005 to Aug.20.2006. The severity of coronary artery stenosis was measuredthough angiography image system. Coronary stenosis≥50% diagnosed in coronaryartery disease. According to the Gensini's method, the severity of lesion wasevaluated. According to the luminar diameter of coronary artery, 50%-75%, 76%-90%,91%-100% were defined as low-grade, middle-grade, high-grade stenosis respectively.According to the number of suffered coronary artery, single-vessel, double-vessel andmulti-vessel groups were defined. According to ACC/AHA classification scheme, A,B, and C types were defined. HOMA-IR≥2.8 enrolled in IR group, HOMA-IR＜2.8enrolled in IS group. Patients' preprandial blood was examed by routine assay.Results:1. Age and IR Mean age was 61.57±9.47 years in IR group, 63.36±8.57 years inIS group. The latter's age was older than the former's, but there was no significantdifference between IR and IS groups. Single-vessel group's mean age wasyoungest, and multiple-vessel group's mean age was oldest. It indicated thatcoronary lesion range became larger with the increase of age.2. Gender and IR The proportion of sex wasn't significantly different between IRand IS groups(P=0.861) and among different lesion range groups (P=0.354).3. Smoking and IR Smoking wasn't significantly different between IR and ISgroups (P=0.431). The proportions of smoking in multiple-vessel and double-vessel groups were higher than in single-vessel group respectively (P＜0.01or P＜0.05).4. Blood pressure and IR The differences in the proportion of hypertensionbetween IR and IS groups and among different lesion range groups werestatistically significant(P=0.000). There were significant differences in meansystolic blood pressure between IR and IS groups and among different lesionrange groups(P=0.048 or P=0.003). Mean diastolic blood pressure was nosignificantly different.5. BMI and IR BMI in IR group was higher than in IS group(P=0.031). Thedifference in BMI among different lesion range groups was statisticallysignificant(P=0.042).6. Blood lipid and IR The levels of TC, TG, and LDL-C in IR group were higherthan in IS group(P=0.311,P=0.027,P=0.16). The level of HDL-C in IR group waslower than in IS group(P=0.000). The levels of TG and LDL-C in multiple-vesseland double-vessel groups were higher than in single-vessel group respectively(P＜0.01 or P＜0.05). The level of HDL-C in single-vessel group was higher than inother groups (P＜0.05). The difference in TC among different lesion range groupswasn't statistically significant(P=0.067).7. FPG, FINS and IR The levels of FPG and FINS in IR group were higher than inIS group(P=0.000). The level of FPG in multiple-vessel group was higher than inother groups(P＜0.01). The levels of FINS in double-vessel and multiple-vesselgroups were higher than in single-vessel group(P＜0.05 or P＜0.01).8. Serum creatinine and IR The level of creatinine in IR group was higher than inIS group(P=0.085). The difference in Cr among different lesion range groupswasn't statistically significant(P=0.228).9. Serum uric acid and IR The level of UA in IR group is higher than in ISgroup(P=0.000). The levels of UA in multiple-vessel and double-vessel groupswere higher than in single-vessel group respectively (P＜0.01 or P＜0.05).10. HOMA-IR and coronary lesion The levels of HOMA-IR in multiple-vessel anddouble-vessel groups were higher than in single-vessel group respectively (P＜0.01 or P＜0.05).11. Correlation analysis between HOMA-IR and the risk factors of coronary heartdisease and multiple linear regression analysis of risk factors and coronary arterylesion Gensini score. Positive correlations were found between HOMA-IR andhypertension, systolic blood hypertension, TG, FINS, FPG, BMI, UA, Gensiniscore (r=0.283～0.937, P=0.000～0.037), a negative correlation betweenHOMA-IR and HDL-C(r=-0.455, P=0.007) by Spearman correlation analysis. Itindicated by multiple linear regression analysis HDL-C was a independentprotecting factor for coronary artery lesion, and systolic blood pressure, LDL-C,UA, HOMA-IR were independentrisk factors.12. IR and coronary artery lesions The incidences of multi-vessel lesion,high-grade lesion, complex lesion, diffuse lesion, C type lesion in IR group werehigher than in IS group(P=0.000). The levels of Gensini score, lesion vesselamount, and lesion amount were higher than in IS group(P=0.000).Conclusions:1. Positive correlations between HOMA-IR and hypertension, systolic bloodhypertension, TG, FINS, FPG, BMI, and UA, the negative correlation betweenHOMA-IR and HDL-C.2. IR may be a risk factor for coronary artery disease, and HOMA-IR may indicatethe coronary artery lesion severity.3. The IR patients have often accompanied with hypertension, obesity, blood lipidmetabolic dysfunction, glucose and insulin metabolic dysfunction, larger coronarylesion range, higher incidence of diffuse and complex lesions.