The relationship of insulin resistance and low adiponectine levels with severity of coronary artery disease

Assessment and elimination of risk factors is mandatory to prevent the development ofcoronary heart disease in healthy individuals and recurrence of coronary accidents in patientswith coronary disease. Hypertension, family history of coronary disease, cigarette smoking,Diabetes mellitus, and dyslipidemia are considered as major risk factors. The role of insulinresistance in the onset and development of coronary disease is not elucidated. The syndromeof insulin resistance is a broad clinical spectrum, which includes obesity, glucose intolerance,diabetes, and the metabolic syndrome, as well as an extreme insulin-resistant state. The overtdiabetes stage is preceded by a prediabetic state characterized by insulin-resistance. Increaseof cardiac mortality and morbidity had been reported in the prediabetic stage usuallyaccompanied with cardiac risk factors such as obesity, hypertension and dyslipidemia. It?s notclear whether the insulin resistance and the resulting hyperinsulinemia are independentcoronary risk factors.Adinopectin is a plasma protein synthesized by adipose tissue of 30 kDA. Reavendescribed in 1988 the syndrome of insulin resistance. He stated a clear relationship betweencardiovascular and metabolic risk factors and the development and progression of CVD anddiabetes. Obesity, particularly central obesity, is an independent risk factor for thedevelopment of CVD and diabetes. Weight gain in adulthood is associated with rising rates ofmultiple cardiovascular and metabolic risk factors and an increased risk of chronic diseases,including diabetes, CHD, hypertension. The relation between diabetes mellitus hypertensionand cardiac mortality deserves more attention. Adiponectin exerts anti-atherogenic effects, bytargeting vascular endothelial cells, Clinical studies revealed decline of adenopectin levels inthe onset of obesity, diabetes mellitus and coronary heart disease.In our study we evaluated the relation between the insulin resistance coronary heartdisease evaluated by coronary angiography.160 patients aged 30-75 years (mean age 59.6+11.4) had been enrolled in our study. Patientswere allocated in three groups according to blood glucose levels: normoglycemics (fastingglucose levels<100mg/dL, n= 54) Impaired glucose tolerance ((fasting glucose levels 120-126mg/dl, n=53) Diabetes Mellitus (fasting glucose levels >126mg/dL, n=53) All patients hadweight height and their belly contour measured at the moment of enrollment. Cardiac riskVIIIfactors, insulinemia, lipid profile and Adiponectin levels were evaluated .The insulinresistance was evaluated . using the homeostasis model assessment insulin resistance FormulaHOMA-IR= basal insulin (mU) x Plasma glucose (mmol/lt) /22.5 HOMA > 2.7 wasconsidered as insulin resistance..All patients had coronary angiography and had Gensini scoring fort he assessment ofseverity of atherosclerosis. The angiographies were classified as normal, obstructive and nonobstructive coronary disease. SPSS 10.0 had been used for statistical analysis.There was no significant difference on insulin levels between the three groups. TheHOMA- IR level representing the insulin resistance was significantly higher in the diabeticgroup. Similarly the highest Gensini scores were found on diabetics. Our results are inagreement with previous studies as diabetes mellitus is considered as equivalent of coronarydisease. But contrary to the previous studious, the adiponectin was significantly higher indiabetic group compared to the two other groups. This may be related to the use of metforminand insulin sensitizing drugs used by our patients.Our study revealed increased insulin resistance and the significance or coronaryatherosclerosis by increasing blood glucose levels. But the adiponectin levels were not lowerin diabetics. We found only weak negative correlation between insulin resistance and Gensiniscores.We conclude that the insulin resistance can be used to predict the coronaryatherosclerosis before it becomes clinically evident. We think that life style modifications,insulin sensitizing drugs and other new treatment strategies can delay the appearance ofdiabetes mellitus and be used in prognosis studies of coronary heart disease.. We could onlyfind a weak negative correlation between adiponectine and Gensini scoring. The mechanismof action of adinopectine and its effect on cardiovascular system is not clear. We don?t knowwhether it?s the cause or the end result of coronary disease. Larger scales studies arenecessary to elucidate these issues.Key Words: Coronary artery disease of severity, insulin resistance, adiponectine