Subject: | |
From: | |
Reply To: | |
Date: | Tue, 26 Nov 2002 17:31:28 EST |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Bill Sardi's analysis of the study purporting that vitamin C and E up heart
disease death. What I find so amazing is the way researchers run with data
that is not statistically significant.
11/20/2002
MORE BAD SCIENCE: BOGUS STUDY FALSELY CLAIMS ANTIOXIDANT VITAMIN PILLS NARROW
CORONARY ARTERIES AND INCREASE MORTALITY AMONG POSTMENOPAUSAL FEMALES WITH
HEART DISEASE
By Bill Sardi, Knowledge of Health, Inc.
The headlines today read: "Antioxidant vitamins and hormone replacement in
older women show no heart health benefits among older women who already have
heart disease. Heart disease appears to progress more quickly among
postmenopausal women who take high doses of vitamins E and C and hormones…
and their use should be discouraged." [Associated Press Nov. 19, 2002]
The bogus study behind these headlines was published in the prestigious
Journal of the American Medical Association. [J Am Med Assoc 288: 2432-40,
2002] The study involved 423 postmenopausal female patients, mean age 65
years, with heart disease who took 800 IU of vitamin E, 1000 milligrams of
vitamin C, or estrogen pills. All the women underwent pre and post-treatment
angiograms, a form of x-ray that shows the course of blood through blood
vessels and chambers of the heart. At least one coronary artery was narrowed
by 15 to 75 percent among women at the beginning of this study. Over a period
averaging 2.8 years, changes in the diameter of the blood vessels were
measured.
Patients who received inactive placebo pills experienced progression of
artery narrowing at the rate of 0.028 millimeters per year whereas the
vitamin and hormone-treated patients experienced narrowing at the rate of
0.044 to 0.047 millimeters per year. But the groups were too small to make
meaningful comparisons. Twenty-six patients experienced a nonfatal heart
attack, a stroke, or died in the hormone replacement group, 26 in the vitamin
group and 18 in the control group. The study indicated decreases in the inner
blood vessel diameter were greater in each of the 3 groups compared to
placebo tablets, "but these trends were not statistically significant." Yet
the conclusive statement at the end of the study said high doses of vitamins
E and C "should be discouraged" among women with coronary artery disease. In
reality, 6.1% of the vitamin and 6.1% of the hormone users and 4.3% of the
placebo pill users died, for a difference in hard numbers of only 1.4%
between groups. But scientific studies use relative numbers which give the
appearance of significance. For the rest of the article go to:
http://askbillsardi.com/sdm.asp?pg=news&specific=54
Namaste, Liz
<A HREF="http://www.csun.edu/~ecm59556/Healthycarb/index.html">
http://www.csun.edu/~ecm59556/Healthycarb/index.html</A>
|
|
|