Relationship between the extent of coronary artery disease and indicators of free radical activity

Clinical studies have demonstrated that patients with coronary artery disease (CAD) have markers suggestive of increased free radical (FR) activity when compared with normal subjects; however, the relationship between the extent of CAD and level of FR markers is not known. The following indices of FR activity, plasma malondialdehyde (MDA), plasma thiols (PSH), red blood cell (RBC) glutathione (GSH), and RBC superoxide dismutase (SOD) were measured in 58 patients admitted for coronary angiography and in 50 matched controls. Regression analysis demonstrated no significant correlation between MDA, PSH, GSH, or SOD, and the angiographic grade which indicated the severity of the CAD. Patients with angiographically proven CAD (median 7.9 nmol/ml IQR 6.9–9.2) and patients with a history suggestive of angina pectoris but normal coronary angiograms (median 8.4 nmol/ml IQR 7.4–9.9) had significantly raised MDA levels compared with the controls (median 6.85 nmol/ml IQR 6.1–7.4), p