Plasma levels of antioxidant vitamins and oxidative stress in patients with acute myocardial infarction.

Of 138 patients with suspected acute myocardial infarction (AMI), 29 were excluded. Remaining 109 patients and 182 healthy controls of similar age and sex and same population were studied in detail for demographic variables, clinical and biochemical data for comparison. Mean age, sex, body weight, body mass index and blood pressures were comparable in the two groups whereas blood lipids, blood glucose and cardiac enzymes were raised in AMI patients compared to controls. Mean levels of vitamin C, E, A and beta-carotene were significantly less in AMI patients than controls whereas the lipid peroxides were significantly higher in AMI patients. The reduction in vitamin C and beta-carotene was more marked than decrease in other vitamins. With in AMI patients, those 28 patients who had cardiac arrhythmias showed greater decrease in vitamins compared to rest of the patients. Within both groups, smokers and diabetes patients had greater reduction in vitamin C and beta-carotene than other patients and subjects without confounding factors. Smokers also had higher lipid peroxides level than non-smokers. The inverse relation between AMI and low plasma vitamin levels remained significant after exclusion of patients with smoking and diabetes. These findings suggest that vitamin deficiency may be a risk factor of AMI and these patients may benefit by administration of these antioxidant vitamins for primary and secondary prevention of coronary artery disease.