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Letter
from Barbara Alving, Acting Director,
National Heart, Lung and Blood FOR
IMMEDIATE RELEASE CONTACT: Friday,
September 24, 2004
NHLBI Communications Office(301) 496-4236 Email: Nhlbi_news@nhlbi.nih.gov
<mailto:Nhlbi_news@nhlbi.nih.gov> Cholesterol
Guidelines: The Strength of
the Science Base and
the Integrity of the Development Process Statement
from Barbara Alving, M.D., Acting Director, National
Heart, Lung, and Blood Institute A
letter initiated by the Center for Science in the Public Interest (CSPI)calls
on the National Cholesterol Education Program (NCEP) to form an independent
panel to review the Adult Treatment Panel III (ATP III, 2001)recommendations
for cholesterol management and a 2004 update to these recommendations.
The September 23 letter, signed by CSPI Executive Director
Michael Jacobson, PhD, and 34 physicians and researchers, questions the scientific
basis and objectivity of these clinical practice guidelines. The
National Institutes of Health and the National Heart, Lung, and Blood Institute
(NHLBI), which coordinates the NCEP, are preparing a detailed response
to the letter. The ATP III
recommendations and the update are based
on a careful analysis of strong and abundant scientific evidence. The
guidelines are objective and the process by which they were developed has
high integrity. Since
its creation in 1985, the NCEP has sought to educate health professionals
and the public about high blood cholesterol as a risk factor
for coronary heart disease (CHD) and the benefits of lowering cholesterol
in the prevention of CHD. The
NCEP is a partnership. At its
core is the Coordinating
Committee, composed of representatives of over 35 partner organizations
including major medical and health professional associations,
voluntary health organizations, community programs, and governmental agencies.
The NCEP, under the sponsorship of the Coordinating Committee,
has developed a series of science-based clinical guidelines on cholesterol
management, known as Adult Treatment Panel reports.
These reports are drafted
by a panel of scientific experts and undergo thorough review by the
Coordinating Committee and other recognized scientific authorities outside
NIH. ATP
III, like the two previous guideline reports from the NCEP, was based
on an extensive examination of the scientific evidence by a panel of leading
scientific experts. This
report has been well received and widely implemented
by the medical community. In
July of 2004, the NCEP issued an
update to ATP III, based on an analysis of 5 new clinical trials of cholesterol
lowering with statin drugs. The
update was drafted by a working
group selected for their expertise from the members of the original ATP III,
and an expert representative of the American Heart Association (AHA) and of
the American College of Cardiology (ACC).
The update paper was reviewed by
the NCEP Coordinating Committee and by the scientific and steering committees
of AHA and ACC, and was endorsed by NHLBI, AHA, and ACC. The
update offered therapeutic options for the physician's consideration rather
than firm recommendations for the most part.
This was done in recognition
of the fact that there are a number of ongoing clinical trials
that will address the benefits of lowering LDL cholesterol well below currently
recommended goal levels. The
CSPI-initiated letter specifically calls into question the ATP III clinical
recommendations for cholesterol lowering in moderately high risk
women and the elderly who do not have heart disease.
NHLBI affirms the scientific
rationale for these recommendations.
Using all available clinical
trial and epidemiological evidence is a well-founded and widely accepted
approach to the development of clinical practice guidelines. NCEP
applies this approach to all recommendations to lower cholesterol - both lifestyle
changes and medication - as well as to all populations, including
women and the elderly. There
is abundant clinical trial and epidemiological evidence showing that
lowering LDL cholesterol (by statins or other means) prevents heart attacks
in men with or without prior coronary heart disease. In addition, there is
considerable evidence from trials of patients with coronary heart disease
or other high risk conditions that statins benefit women and men, older
and younger
patients, and those with and without diabetes.
Since narrowing of
the coronary arteries is a lifelong gradual process, there is no scientific
basis to believe that cholesterol lowering suddenly becomes beneficial the
moment a person has a heart attack. It
is far more consistent with the entire
body of scientific evidence to hold that cholesterol lowering is also
beneficial in people without heart disease, but becomes even more critical
after a heart attack, when the person's risk for a future heart attack rises
significantly. Recent
clinical trials, including the Heart Protection Study, strengthen ATP
III recommendations for older persons, an age group which exhibits the highest
risk for heart attacks. Regarding
research on women, this same large
trial included over 5,000 high-risk women and showed the same benefit
of LDL-lowering therapy as observed in men.
In this trial, over 1,800 women
had diabetes and they too benefited from LDL lowering.
Although clinical
trials have not included large numbers of moderately high risk women (without
heart disease), epidemiological studies show that these women are
just as likely to develop cardiovascular disease as men.
ATP III thus applied
the same guidelines to both men and women at moderately high risk. It
is imperative that we apply what we have learned from research in order
to prevent or delay the development of heart disease, the leading killer of
women and men. For tens of
thousands of Americans, including women and the
elderly, the first sign of heart disease is sudden death.
Sound public health
policy demands that the significant risk for illness and death in women
and the elderly be addressed with science-based prevention recommendations. The
letter also questions the ATP III recommendation that high-risk patients
with diabetes should be considered for cholesterol-lowering drug therapy.
In fact, there is conclusive clinical trial evidence that cholesterol-lowering
drug therapy significantly reduces cardiovascular risk
for patients with diabetes, both those with and without existing heart disease.
This finding has been amply documented by a major primary prevention
trial in patients with diabetes that was published after the ATP
III update. Once a person
with diabetes develops cardiovascular disease,
the mortality rate is very high, so the objective in diabetes treatment is
to prevent the development of cardiovascular disease in the first place. Clinical
trials show that cholesterol lowering contributes significantly to
attaining this objective. The
letter questions the objectivity of ATP III and the update, stating that
the recommendations "may not be scientifically justified" since
panel members
have had interactions with the pharmaceutical industry.
We have noted
before that the experts who are most knowledgeable in a subject area
are also the same people whose advice is sought by industry, and most guideline
panels include experts who interact with industry.
To ensure that
the guidelines are objective and science-based, NHLBI employs a rigorous development
and review process. Expert panel members are carefully selected
for their scientific and medical expertise and their integrity, multiple levels
of reviewers scrutinize the drafts of the guidelines from a variety
of scientific perspectives, and financial disclosure is published by the peer-reviewed
journal. Many
journals and organizations are currently reexamining their approaches
to managing disclosure of financial interests.
NHLBI is developing further
policy in this area to refine the process for management of potential conflict
of interest. In
summary, the ATP III guidelines and update were developed using a thorough
evidence-based process that has high integrity.
The guidelines are
derived from an objective analysis of the substantial scientific evidence
and NHLBI stands behind them. There are several clinical trials in high-risk
individuals currently underway. The
results of these trials will help determine
whether revisions to the current recommendations are scientifically
warranted. At that time, NCEP
will consider establishing another
panel. More
detailed information on the issues raised by the letter and the NHLBI
response to the letter will be made available after the response to the letter
has been finalized. The ATP III guidelines and update can be found online
at: http://www.nhlbi.nih.gov/guidelines/cholesterol/index.htm <http://www.nhlbi.nih.gov/guidelines/cholesterol/index.htm>
. NHLBI
is part of the National Institutes of Health (NIH), the Federal Government's
primary agency for biomedical and behavioral research. NIH is
a component of the U.S. Department of Health and Human Services. NHLBI press
releases and fact sheets can be found online at www.nhlbi.nih.gov
Read also Malcolm Kendrick´s comment
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