Positive Health Online

Abstract

TORNWALL and colleagues, ATBC Study, Department of Nutrition, National Public Health Institute, Mannerheimintie 166, 00300, Helsinki, Finland, markareetta.tornwall@ktl.fi evaluated the effects of long-term vitamin E (alpha-tocopherol) supplementation on male smokers with intermittent claudication.

Background

Methodology

Study subjects (n=1,484) – male smokers aged 50-69 years – were participants in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study who reported intermittent claudication in a structured (Rose) questionnaire at entry to the study. They were assigned randomly to receive: a) 50 mg/day alpha-tocopherol; b) 20 mg/day beta-carotene; c) both of these supplements; or d) placebo in a 2 x 2 study design. During follow-up, claudication was evaluated by repeating use of the questionnaire once a year. Information about subjects who underwent peripheral vascular surgery was obtained from the National Hospital Discharge Register.

Results

No effect of alpha-tocopherol or beta-carotene supplementation on claudication was seen during a mean follow-up of 3.7 years. Men who received beta-carotene had a slightly increased risk for vascular surgery (odds ratio (OR) 1.60), compared to those who did not receive beta-carotene. Alpha-tocopherol supplementation had no effect on the risk for vascular surgery.

Conclusion

Long-term supplementation with alpha-tocopherol and/or beta-carotene showed no beneficial effect on the symptoms or progression of intermittent claudication.

References

Tornwall ME et al. The effect of alpha-tocopherol and beta-carotene supplementation on symptoms and progression of intermittent claudication in a controlled trial. Atherosclerosis 147 (1): 193-7. Nov 1999.

Comment

The participants in the above study were from the famous (or should I say infamous) Finnish Beta-Carotene smokers trial, in which heavy smokers (35 cigarettes/day) who had primarily also worked with asbestos were given a number of nutritional supplements, including beta-carotene, in order to assess beta-carotene’s potential cancer-preventive effects. The trial received headline news several years ago when the beta-carotene group actually had a slightly higher rate of lung cancer than the controls. (See also www.positivehealth.com, Reviews, Items of Interest, for a fuller discussion of this trial.) There are two points of potential criticism in the above assessment of vitamin E and beta-carotene for claudication: 1) that the amounts given were insufficient; and 2) that after a lifetime of smoking, which would wreak havoc on the circulatory system, a token supplementation with vitamins for a few years would never be expected to exert a therapeutic effect.