alpha-Tocopherol (vitamin E) and beta-carotene supplementation does not affect the risk for large abdominal aortic aneurysm in a controlled trial

Antioxidants may retard atherogenesis and limit inflammatory processes invo lved in aneurysm formation. We evaluated effects of alpha -tocopherol and b eta -carotene supplementation on incidence of large abdominal aortic aneury sm (AAA) in a randomised, double-blind, placebo-controlled trial. Subjects (n = 29 133) were 5069-years-old male smokers, participants: in the Finnish alpha -Tocopherol. beta -Carotene Cancer Prevention (ATBC) Study. They wer e randomised to receive either 50 mg/day of alpha -tocopherol, or 20 mg/day of beta -carotene, or both, or placebo in a 2 x 2 design. Incidence of AAA was: evaluated from mortality and hospital registers. During 5.8 years of follow-up, 181 men were diagnosed with either ruptured AAA (n = 77) or nonr uptured large AAA treated with aneurysmectomy (n = 104). Relative risk (RR) for AAA was 0.83 (95% confidence interval [CI] 0.62 1.11) among men receiv ing a-tocopherol compared with those who did not, and 0.93 (95% CI 0.69-1.2 4) among men receiving beta -carotene compared with those who did not. A mo dest though nonsignificant decrease in risk for nonruptured AAA was observe d among sc-tocopherol supplemented men (RR 0.71, 95% CI 0.48-1.04) compared with men not receiving alpha -tocopherol. For beta -carotene, RR for nonru ptured AAA was 0.86 (95% CI 0.59 1.27) compared with men not receiving beta -carotene. Neither antioxidant affected risk for ruptured AAA. In conclusi on, long-term supplementation with alpha -tocopherol or beta -carotene had no preventive effect on large AAA among male smokers. (C) 2001 Elsevier Sci ence Ireland Ltd. All rights reserved.