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Verdict: Vitamins may not be good for heart disease

It seems like common sense that vitamins are good for you. Right? Especially in patients who had a heart attack. Right? We’ve heard for years that antioxidant vitamins eat up “free radicals” in the body that could be harmful. Although certain vitamins are important to get in our diets such as vitamin D for bone health, evidence has been piling up over the last few years that suggests some antioxidants and vitamins are not good for patients with heart disease.

September 2003 - European Society of Cardiology meeting: Vitamin E fails to show benefit in patients at high risk for heart disease

The HOPE trial studied an ACE inhibitor called ramipril (Altace) in patients that did not have heart failure or high blood pressure (hypertension) but were considered high risk. The study also divided patients into groups that would to receive vitamin E 400 IU or placebo in a separate analysis called HOPE-TOO. The HOPE-TOO part of the trial that looked at vitamin E followed about 7000 patients for over 7 years. Vitamin E did not reduce the risk of cancer, death from cancer, or developing heart disease. There was actually the opposite - patients were more likely to develop heart failure or be hospitalized for heart failure. Results were later published in the Journal of the American Medical Association (JAMA 2005; 293: 1338-1347.)

November 2004 - American Heart Association meeting: Vitamin E increases death

• Simultaneously published in Annals of Internal Medicine by Dr Edgar Miller III (Johns Hopkins University, Baltimore, MD), this study combined data from 19 older trials of vitamin E.
• It brought together 135,967 participants who received vitamin E in doses as low as 16.5 IU/day to as high as 2000 IU/day (most common dose was 400 IU/day).
• Above 150 IU/day, risk of death gradually increased to about 8% higher than those not taking vitamin E.
• Below 150 IU/day, there was no definite harm or benefit. (Ann Intern Med. 2005 Jan 4;142(1):37-46. Epub 2004 Nov 10.)

What were the weaknesses or criticisms of this study? It combined lots of trials with variable designs; different extra medications or herbals; some trials used natural sources of vitamin E and others synthetic. Lastly, many of the patients had chronic diseases so results cannot be generalized to a healthy population who might be looking for prevention of diseases. So there were definitely concerns, but it raised some questions to think about. Months later at the American College of Cardiology meeting, more evidence started to stack up against vitamin E.

March 2005 - Vitamin E fails in primary prevention of heart disease for women

“Primary prevention” means trying to prevent a first heart attack or other bad outcome. Dr Julie E Buring (Brigham and Women’s Hospital, Boston, MA) presented findings from the Women’s Health Study. Almost 40,000 women were given either vitamin E or placebo. Another part of the study examined aspirin for primary prevention. This is discussed elsewhere. But for vitamin E, cardiovascular events were not reduced. There was a slight reduction in deaths from heart events (cardiovascular death), but the overall death rate was the same in both treatments.

So if you are keeping track, it seems the jury is against vitamin E in patients with chronic disease and in women to prevent heart disease. Another study looking at women already at high risk for heart disease was released in 2007.

February 2007 - Vitamin C, vitamin E, or beta-carotene supplements show no benefit

Investigators from Denmark led by Dr Goran Bjelakovic (Copenhagen University Hospital, Denmark) combined data from 68 previous trials of 232 606 participants. When all the studies were combined, there seemed to be no harm or benefit on the risk of death. But when the studies that might have a high risk or low risk of bias were removed, 180 938 participants were left. The antioxidant supplements together significantly increased mortality by about 5%. By themselves, beta-carotene, vitamin A, and vitamin E each had some increase on mortality. The jury was still out on Vitamin C and selenium - neither had an effect on mortality. (JAMA 2007; 297:842-857). As you can imagine, this controversial study created some hot debate.

August 2007 - Vitamin C, vitamin E, or beta-carotene supplements show no benefit in women

Dr Nancy R Cook (Brigham and Women’s Hospital and Harvard Medical School, Boston, MA) led the Women‘s Antioxidant Cardiovascular Study (WACS) with over 8000 women over 40 years of age who either had heart disease or 3+ risk factors. Participants were to randomized three times to three different antioxidants: ascorbic acid (Vitamin C) 500 mg/day, vitamin E 600 IU every other day), and beta carotene 50 mg every other day. The investigators examined the combined outcome of myocardial infarction (heart attack), stroke, coronary revascularization (by-pass surgery or angioplasty), or cardiovascular death. There was no benefit for this outcome. (Arch Intern Med. 2007;167:1610-1618)

August 2007 - American Heart Association and American College of Cardiology weigh in on vitamin debate

The latest AHA/ACC guidelines for patients that have unstable angina or non-ST-elevation myocardial infarction were published with a comment on vitamins. What is unstable angina and non-ST-elevation myocardial infarction? (briefly: there are three types of heart attacks - these have less blockage than the biggest heart attack called ST-elevation myocardial infarction, but they are still very dangerous) The guidelines state very clearly:

• Antioxidant vitamin supplements (e.g., vitamins E, C, or beta carotene) should not be used for secondary prevention in UA/NSTEMI patients.
• Folic acid, with or without B6 and B12, should not be used for secondary prevention in UA/NSTEMI patients.
  

(ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2007)

Final word: It is important to keep in mind that usually only “good” studies that show benefit are published. Many researchers are less likely to publish negative or neutral studies. So if the evidence is leaning away from certain vitamins, the effect may be more pronounced if more negative trials were released.