PureInsight | February 5, 2007
Heart Attack Prevention: In primary prevention trials, taking statins did not help women.
Over the last decade or two, it seems that increasing pressure has been
put on us to have our cholesterol levels measured, and to do something
about them if these turn out to be raised. Elevated cholesterol levels
in the bloodstream are often said to be a potent risk factor for
cardiovascular disease, which can ultimately lead to unwanted and
potentially fatal heart attacks and strokes.
From a conventional medical perspective, the mainstay treatment for
reducing cholesterol is known as statins, which include atorvastatin
(Lipitor), rosuvastatin (Crestor), and simvastatin (Zocor). A huge
stash of cash has been made out of these drugs, but is their
life-saving reputation deserved?
Let's get clear on the two fundamental ways statins may be used for the
prevention of cardiovascular disease. Firstly, for people who have no
evidence of cardiovascular disease, known as primary prevention.
Secondly, in individuals with heart disease, or who have already had a
heart attack or stroke. This is described as secondary prevention.
Individuals with a history of cardiovascular disease, compared to
healthy individuals, are at a higher risk of heart attacks and strokes.
As a result, they are more likely to benefit from statin therapy, and
studies have found that statins do reduce the risk of death.
Scientists have generally assumed that these benefits also apply to primary prevention, but do they?
In the Jan. 20, 2007, issue of The Lancet, an editorial examined this
issue. Its authors present their review of eight predominantly primary
prevention trials. This showed that statin therapy was NOT effective in
reducing overall risk of death. The study found that risk of heart
attacks and strokes were reduced by 1.5 percent with statin therapy.
What is more, 67 individuals would need to be treated for five years
for just one event to be prevented. One of the most startling findings
was that there was no apparent benefit seen in women (of any age) nor
in men under the age of 70.
The authors of The Lancet review draw our attention to a group of
scientists known as the Cholesterol Treatment Trialists' (CTT)
collaboration, who in the past have assessed data from studies, which
include both primary and secondary prevention, and have the data they
need to calculate the effect of statin therapy in a purely primary
setting. One wonders why they haven't done this crucially important
Past events suggest this may have something to do with politics and
money. Back in 2004, there was a significant lowering of what are
regarded as acceptable levels of cholesterol, as recommended by a group
known as the National Cholesterol Education Program (NCEP) expert panel
in the United States. After its recommendations were made and taken up,
it came out that eight out of nine members of the panel had financial
links with drug companies making statin drugs. The report's publisher
described the omission of these clear conflicts of interest as an
"oversight." I'll say!
I suppose this wouldn't matter too much if the recommendations to lower
cholesterol upper limits were based on good science. The scientific
basis for the recommendations made by the NCEP expert panel was
reviewed in the Annals of Internal Medicine in 2006. The authors of
this review stated: "In this review, we found no high-quality clinical
evidence to support current treatment goals for [LDL] cholesterol."
They went on to say that the practices recommended by the NCEP expert
panel were not scientifically proven to be beneficial or safe.
In response to The Lancet editorial, which amounts to quite a damning
appraisal of statin therapy, the media has reacted with deafening
silence. I think it's great that researchers who are not in the pay of
the pharmaceutical industry are prepared to ask hard questions about
the presumed value of medication. But I also think it's a shame that
these researchers lack the funds needed to give such important work the
airing it deserves.
1. Abramson J, Wright JM. Are lipid-lowering guidelines evidence-based? Lancet 2007; 369:168-169
2. Jauca C, Wright JM. Therapeutics letter: update on statin therapy.
International Society of Drug Bulletins Newsletter. 2003; 17:7-9
3. Cholesterol Treatment Trialists' (CTT) Collaborators. Efficacy and
safety of cholesterol-lowering treatment: Lancet 2005; 366: 1267-1278
4. Hayward RA. Narrative review: lack of evidence for recommended
low-density lipoprotein treatment targets: Annals of Internal Medicine