MRC/BHF Heart Protection Study of antioxidant vitamin supplementation in 20,536 high-risk individuals: a randomised placebo-controlled trial

Lancet. 2002 Jul 6;360(9326):23-33. doi: 10.1016/S0140-6736(02)09328-5.

Abstract

Background: It has been suggested that increased intake of various antioxidant vitamins reduces the incidence rates of vascular disease, cancer, and other adverse outcomes.

Methods: 20,536 UK adults (aged 40-80) with coronary disease, other occlusive arterial disease, or diabetes were randomly allocated to receive antioxidant vitamin supplementation (600 mg vitamin E, 250 mg vitamin C, and 20 mg beta-carotene daily) or matching placebo. Intention-to-treat comparisons of outcome were conducted between all vitamin-allocated and all placebo-allocated participants. An average of 83% of participants in each treatment group remained compliant during the scheduled 5-year treatment period. Allocation to this vitamin regimen approximately doubled the plasma concentration of alpha-tocopherol, increased that of vitamin C by one-third, and quadrupled that of beta-carotene. Primary outcomes were major coronary events (for overall analyses) and fatal or non-fatal vascular events (for subcategory analyses), with subsidiary assessments of cancer and of other major morbidity.

Findings: There were no significant differences in all-cause mortality (1446 [14.1%] vitamin-allocated vs 1389 [13.5%] placebo-allocated), or in deaths due to vascular (878 [8.6%] vs 840 [8.2%]) or non-vascular (568 [5.5%] vs 549 [5.3%]) causes. Nor were there any significant differences in the numbers of participants having non-fatal myocardial infarction or coronary death (1063 [10.4%] vs 1047 [10.2%]), non-fatal or fatal stroke (511 [5.0%] vs 518 [5.0%]), or coronary or non-coronary revascularisation (1058 [10.3%] vs 1086 [10.6%]). For the first occurrence of any of these "major vascular events", there were no material differences either overall (2306 [22.5%] vs 2312 [22.5%]; event rate ratio 1.00 [95% CI 0.94-1.06]) or in any of the various subcategories considered. There were no significant effects on cancer incidence or on hospitalisation for any other non-vascular cause.

Interpretation: Among the high-risk individuals that were studied, these antioxidant vitamins appeared to be safe. But, although this regimen increased blood vitamin concentrations substantially, it did not produce any significant reductions in the 5-year mortality from, or incidence of, any type of vascular disease, cancer, or other major outcome.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antioxidants / therapeutic use*
  • Ascorbic Acid / blood
  • Ascorbic Acid / therapeutic use*
  • Cardiovascular Diseases / mortality
  • Cardiovascular Diseases / prevention & control*
  • Cause of Death*
  • Cholesterol / blood
  • Coronary Disease / drug therapy*
  • Diabetes Mellitus / drug therapy*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Neoplasms / prevention & control*
  • Severity of Illness Index
  • Stroke / classification
  • Stroke / mortality
  • Stroke / prevention & control
  • United Kingdom
  • Vitamin E / blood
  • Vitamin E / therapeutic use*
  • beta Carotene / blood
  • beta Carotene / therapeutic use*

Substances

  • Antioxidants
  • beta Carotene
  • Vitamin E
  • Cholesterol
  • Ascorbic Acid