The effect of alpha-tocopherol and beta-carotene supplementation on symptoms and progression of intermittent claudication in a controlled trial.

We evaluated the effect of long-term supplementation with vitamin E (alpha-tocopherol) and beta-carotene on occurrence of claudication symptoms and risk for peripheral vascular surgery among men with intermittent claudication. Subjects, 50-69-year old male smokers, were participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, who reported intermittent claudication through a structured questionnaire (Rose) at study entry (n=1484). They were randomly assigned 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. During follow-up, claudication was evaluated by repeating use of the questionnaire once a year. Information on peripheral vascular surgery came from the National Hospital Discharge Register. We observed no effect of alpha-tocopherol and beta-carotene supplementation on claudication during a mean follow-up of 3.7 years. A slightly increased risk (odds ratio (OR) 1.60, 95% confidence interval (CI) 1.05-2.44) for vascular surgery was observed among beta-carotene supplemented men compared to those who did not receive beta-carotene. Alpha-tocopherol supplementation had no effect. In conclusion, long-term supplementation with alpha-tocopherol and beta-carotene showed no beneficial effect on symptoms and progression of intermittent claudication.