Age-Related Eye Disease Study
AREDS Coordinating Center
Dear AREDS Participant, A paper to be published in the January
2005 edition of the Annals of Internal Medicine will report that
taking high-dose vitamin E supplements does not lower the risk
of death, and might be associated with a small increase in the
risk of death. The material in this paper was recently presented
at a meeting of the American College of Physicians in New Orleans
and this presentation has received much attention from the press.
The authors conducted an analysis looking at the risk of death
by combining data from 19 clinical trials testing vitamin E as
a possible treatment for many different diseases. Results from
the Age-Related Eye Disease Study (AREDS) were included in the
analysis. We are writing to tell you about the results of this
report and why we believe taking 400 International Units (IU)
of vitamin E as part of the AREDS formulation does not increase
the risk of death of persons at risk for advanced AMD. In this
new study, the authors concluded that, “high-dosage (= 400
IU) vitamin E supplements may increase all-cause mortality.”
Their data does seem to show that persons taking particularly
high doses of vitamin E (500 IU to 2000 IU) may have some increased
risk of death, but even at the high doses, the risks observed
for patients ranged from a benefit of 2% to a risk of 5%, with
most of the studies having an excess risk between 0.5% and 4%.
In addition, it is not clear that this possible increased risk
for very high doses would apply to persons taking 400 IU. This
is important to our study participants because this is the dose
of vitamin E in the AREDS formulation. Looking at all the studies
included in this new analysis of vitamin E, there are three studies,
including AREDS, that evaluated about 400 IU of vitamin E daily
(two 400 IU and one 440 IU). There were over 15,000 patients followed
in these three studies and over 1600 total deaths in this generally
elderly population. In total, the group taking the vitamin E was
actually just slightly more likely to be living after 5 years
(801 deaths out of 7564 persons in the vitamin E group and 806
deaths out of 7598 in the placebo group). This means there was
essentially no difference in the risk of dying between those who
took about 400 IU vitamin E and those who did not in a large number
of patients studied. If the reason for taking vitamin E is to
decrease mortality, we agree with the authors of this new study
that there does not seem to be any benefit of vitamin E for most
patients and there might be some harm at high doses. However,
as you know, if you are at high risk for developing advanced age-related
macular degeneration (AMD), there is a benefit in taking the AREDS
formulation that includes vitamin E. AREDS data show that you
can reduce the risk of developing advanced AMD by about 25%. The
AREDS data also indicate that the antioxidants in the formulation
were partly responsible for that benefit. This means the possible
benefit of vitamin E should be considered when deciding whether
to take the AREDS formulation. The AREDS formulation contains
a number of antioxidants and minerals other than just vitamin
E. We also looked at the risk of death in AREDS for those who
were taking the AREDS formulation compared with those who were
assigned to the placebo group. Those taking the AREDS formulation
actually had a 12% reduction in 5-year mortality risk. Although
this reduction in mortality risk was not statistically significant,
and we cannot say that the formulation will improve your longevity,
it does suggest that taking the AREDS supplement is unlikely to
increase your risk of dying. Because different patients have different
needs, it is important to discuss with your doctor whether this
formulation is right for you.
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