[Oxidant stress and cardiovascular absolute risk in Tunisian type 2 diabetes]

cardiovascular diseases constitute the most hefty complications in diabetes. Absolute cardiovascular risk (ACVR) can be estimated by many equations that are continuously criticised. The aim is, in one hand, to evaluate ACVR in type 2 diabetes and, in the other hand, is to establish correlations between ACVR and oxidant-antioxidant status.

183 type 2 diabetes and 200 controls were admitted. ACVR assessment was calculated following Laurier equation. Oxidant status was evaluated by the measure of homocysteine, hydrogen peroxide (H2O2) and LDL thiobarbituric reactive oxygen substances (LDL-TBARS). Antioxidant status was evaluated by the measure of superoxide dismutase (SOD) activity, glutathione peroxidase (GPx), total antioxidant status (TAS) vitamins A, E and zinc. Glycated haemoglobin (HbA1c) and microalbuminuria were assessed by turbidimetry.

ninety percent of diabetes belonged to moderate and high ACVR groups. In diabetic men ACVR was doubled each elevation of 4 micromol/L homocysteine, of 50 micromol/L of H2O2 and of 20 mg/L of microalbuminuria. High risk ACVR group showed the lowest SOD activity, zincemia and the highest HbA1c. No significant difference was found in LDL-TBARS, TAS, GPx, vitamins A, E between the different ACVR groups. The strong relation between homocysteine and ACVR confirms homocysteine atherosclerotic role. Homocysteine auto-oxidation produces H2O2 leading to LDL-TBARS increase. Microalbuminuria-ACVR association verifies its vasculopathy predictor role. Urinary albumin leakage may be consequent to the hyperhomocysteinemia found in diabetes.

homocysteine introduction in ACVR assessment equation may ameliorate this estimation.