Plasma coenzyme Q(10) concentrations are not decreased in male patients with coronary atherosclerosis

Coenzyme Q(10) (CoQ(10)) is an important mitochondrial electron transfer co mponent and has been postulated to function as a powerful antioxidant prote cting LDL from oxidative damage. It could thus reduce the risk of cardiovas cular disease. Thus far, beneficial effects of supplementation with CoQ(10) have been reported. To study the relation between unsupplemented concentra tions of plasma CoQ(10) and coronary atherosclerosis, we performed a case-c ontrol study among 71 male cases with angiographically documented severe co ronary atherosclerosis and 69 healthy male controls free from symptomatic c ardiovascular disease and without atherosclerotic plaques in the carotid ar tery. Plasma CoQ(10) concentrations (mean +/- SE) were 0.86 +/- 0.04 vs. 0.83 +/- 0.04 mu mol/l for cases and controls, respectively. The CoQ(10)/LDL-choles terol ratio (mu mol/mmol) was slightly lower in cases than in controls (0.2 2 +/- 0.01 vs. 0.26 +/- 0.03). Differences in CoQ(10) concentrations and Co Q(10)/LDL-cholesterol ratio did not reach significance. The odds ratios (95 % confidence interval) for the risk of coronary atherosclerosis calculated per mu mol/l increase of CoQ(10) was 1.12 (0.28-4.43) after adjustment for age, smoking habits, total cholesterol and diastolic blood pressure. We conclude that an unsupplemented plasma CoQ(10) concentration is not rela ted to risk of coronary atherosclerosis.