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Background: Enhanced oxidative stress has been associated with atherosclerosis and coronary artery disease (CAD). However, the predictive value of circulating oxidative stress biomarkers for cardiovascular events (CE) in patients with CAD has remained poorly understood. Aim: To assess the prognostic signifi cance of reactive oxygen metabolites, estimated as index of oxidative stress in serum samples by means of a commercial kit (ROMs, Diacron, Italy) on the rate of mortality and major adverse CE (MACE) in CAD. Methods: A study of 93 consecutive patients with angiographically documented CAD (75 males, age: 68 ± 10 years, mean ± SD) was made during a mean follow-up of 66 months until the occurrence of one of the following CE: cardiac and all cause death, non-fatal myocardial infarction and coronary revascularization [percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG)]. Patient data were retrospectively collected from the Institute ’ s electronic databank that saves demographic, clinical, instrumental and follow-up data of all patients admitted to our department. Results: The Kaplan-Meier survival estimates showed a signifi cantly worst outcome in patients presenting elevated ROM level ( > 75th percentile, corresponding to 481 AU) (log rank = 11, 7.5, 5.1; p < 0.001, p < 0.01, p < 0.05 for cardiac and all cause death and MACEs, respectively). In a multivariate Cox regression model, elevated oxidative stress remained a signifi cant predictor of cardiac and all cause death [hazard ratio (HR) 3.9, 95 % confi dence interval, 95 % (CI) 1.4 ‐ 11.1, p = 0.01; HR = 2.6, 95 % CI 1.1 ‐ 6.2, p = 0.02) and MACE (HR = 1.8, 95 % CI 1.1 ‐ 3.1, p = 0.03)]. Conclusions: The estimation of ROMs may represent an additional prognostic tool in the assessment of CE in CAD patients.

Several methods to assess the total antioxidant capacity (TAC) are available. However, the final value of measured TAC in the sample depends on the procedure used in every specific assay. This makes crucial the comparison of different analytical methods. The aim of our study was to evaluate analytical characteristics and laboratory reliability of two different assays: the ferric-reducing ability (FRAP) assay and a new spectrophotometric test (OXY-adsorbent test, Diacron, Italy).Unselected outpatients referred to the Institute of Clinical Physiology were studied (n=187, 58 females, 129 males, mean age: 65±13 years). All blood samples were maintained on ice, centrifuged within 15 minutes after blood collection and then stored at −80°C until performance of assay procedures.OXY assay: The lower limit of sensitivity was 6 μmol HClO/ml. The assay was found to be linear up to 440 μmol HClO/ml (r=−0.99, pFRAP assay: The lower limit of sensitivity was 15 μmol/l. Linearity was observed up to 1000 μmol/l (r=−0.998, pFRAP vs. OXY: A significant direct relationship was observed when comparing FRAP with OXY levels in the whole population (r=0.22, pNeither of the methods are expensive and they are speedy and simple to perform. Values are reproducible and linearly correlated to the concentration of antioxidants present in the samples. For this reason, these methods may be considered practicable indicators of total antioxidant capacity, for routinely potential use in every laboratory and useful in all the studies concerning the evaluation of oxidative stress.

The aim of this study was to evaluate the analytical performance and clinical usefulness of spectrophotometric assays for the measurement of the plasma levels of nitrite plus nitrate (NOx), and malondialdehyde (MDA), as an index of nitric oxide release and lipid peroxidation, respectively. We studied 30 healthy sedentary volunteers, 12 endurance athletes and 12 regular heavy smokers. The lower limit of quantification for plasma NOx concentration was 1 µmol/l, and linearity was observed from 1 to 40 µmol/l of NOx concentration. Variation in replicate samples within or between days was always below 5%. NOx levels were significantly higher in athletes compared to both control subjects and smokers (p