Effect of alpha-tocopherol and beta-carotene supplementation on coronary heart disease during the 6-year post-trial follow-up in the ATBC study

Abstract

Aims: To evaluate the 6-year post-trial effects of alpha-tocopherol and beta-carotene supplementation on coronary heart disease (CHD) in the alpha-tocopherol, beta-carotene cancer prevention (ATBC) study.

Methods and results: 29,133 male smokers, aged 50-69 years were randomised to receive alpha-tocopherol 50 mg, or beta-carotene 20 mg, or both, or placebo daily for 5-8 years. At the beginning of the post-trial follow-up, 23,144 men were still at risk for a first-ever major coronary event (MCE), and 1255 men with pre-trial history of myocardial infarction (MI) were at risk for MCE. Post-trial risk for MCE (n=2059) was 0.95 (95% confidence interval 0.87-1.04) among alpha-tocopherol recipients compared with non-recipients, and 1.14 (1.04-1.24) among beta-carotene recipients compared with non-recipients. The risk for non-fatal MI (n=993) was 0.96 (0.85-1.09) and 1.16 (1.03-1.32), and for fatal CHD (n=1066) 0.94 (0.83-1.06) and 1.11 (0.99-1.25), respectively. Among men with pre-trial MI no effects were observed in post-trial risk of MCE (n=257).

Conclusion: beta-Carotene seemed to increase the post-trial risk of first-ever non-fatal MI but there is no plausible mechanism to support it. Our findings do not advocate the use of alpha-tocopherol or beta-carotene supplements in prevention of CHD among male smokers.