Should high dose vitamin E be prescribed for patients with CAD?

Emily E. Hass
November 22, 1996

Clinical scenario:
A 70 year old male patient with known significant CAD refuses surgical treatment but
wants medical therapy. He has been taking an antioxidant since he saw a report on the
CBS Evening News with Dan Rather proclaiming its virtues and wants to know if this will
help his heart disease. To your utter despair, he wants facts and he wants them now.
Desparately, you quickly make up sensitivities and specificities like Dr. Kizer. Only later
in a small, crowded conference room with 65 people and 60 chairs do you learn the true
data.

Clinical bottom lines:

1. At doses of > 400 IU a day, vitamin E reduces the risk of non-fatal MI and"cardiovascular event".

2. Largest benefits are obtained with only long-term supplementation.

The Evidence:

A prospective, double-blind controlled trial of 2002 patients with angiographically proven CAD randomized to receive vitamin E (400 or 800 IU) or placebo.

CHAOS endpoints Vitamin E n=1035 Placebo n=967 RRR ARR NNT
non-fatal MI 0.0135 0.0424 69% .029 35
cardiovascular death 0.026 0.024 -8% -0.02 NA
cardiovascular event 0.087 0.164 47% 0.78 13

Comments:

1. Largest benefits were obtained at >200 days after beginning treatment. More deaths
occurred prior to the 200 day mark.

2. Though the treatment group received two different doses of vitamin E doses were not distinguished or compared in the analysis.

3. Vitamin E supplementation is very cheap with almost no side-effects.

Reference:
Stephens NG, Parsons A, Schofield PM, et al. Randomised controlled trial of vitamin E in patients with coronary disease: Cambridge Heart Antioxidant Study (CHAOS). Lancet. 1996Mar 23:347:781-6.