Vitamin E Supplementation and Cardiovascular Events in High-Risk Patients

A systematic review 2 including 84 studies (all RCTs) was abstracted in DARE. There was no statistically significant difference between vitamin E and placebo in terms of all-cause mortality (5 trials; relative risk ratio 0.96, 95% CI: 0.84 to 1.10). There was no statistically significant difference between vitamin E and placebo in terms of cardiovascular deaths (5 trials; relative risk ratio 0.97, 95% CI: 0.80 to 1.19). There was no statistically significant difference between vitamin E and placebo in terms of fatal MI (5 trials; relative risk ratio 0.97, 95% CI: 0.74 to 1.27). There was no statistically significant difference between vitamin E and placebo in terms of nonfatal MI (5 trials; relative risk ratio 0.72, 95% CI: 0.51 to 1.02).

One of tfhe included studies, the HOPE study 1 assessed the effects of of vitamin E in patients at high risk for cardiovascular events because of cardiovascular disease or diabetes in addition to one other risk factor. These patients were randomly assigned according to a two-by-two factorial design to receive either 400 IU of vitamin E daily from natural sources or matching placebo and either an angiotensin-converting-enzyme inhibitor (ramipril) or matching placebo for a mean of 4.5 years (the results of the comparison of ramipril and placebo are reported in a companion article). A total of 772 of the 4761 patients assigned to vitamin E (16.2 percent) and 739 of the 4780 assigned to placebo (15.5 percent) had a primary outcome event (relative risk, 1.05; 95 percent confidence interval, 0.95 to 1.16; P=0.33). There were no significant differences in the numbers of deaths from cardiovascular causes (342 of those assigned to vitamin E vs. 328 of those assigned to placebo; relative risk, 1.05; 95 percent confidence interval, 0.90 to 1.22), myocardial infarction (532 vs. 524; relative risk, 1.02; 95 percent confidence interval, 0.90 to 1.15), or stroke (209 vs. 180; relative risk, 1.17; 95 percent confidence interval, 0.95 to 1.42). There were also no significant differences in the incidence of secondary cardiovascular outcomes or in death from any cause. There were no significant adverse effects of vitamin E.

References

• Yusuf S, Dagenais G, Pogue J, Bosch J, Sleight P. Vitamin E supplementation and cardiovascular events in high-risk patients. The Heart Outcomes Prevention Evaluation Study Investigators. N Engl J Med 2000 Jan 20;342(3):154-60. [PubMed]
• Shekelle PG, Morton SC, Jungvig LK, Udani J, Spar M, Tu W, J Suttorp M, Coulter I, Newberry SJ, Hardy M. Effect of supplemental vitamin E for the prevention and treatment of cardiovascular disease. J Gen Intern Med 2004 Apr;19(4):380-9. [PubMed] [DARE]