Cardiovascular disease (CVD) is still
unchallenged as the number one
killer in the United States as it has
been for virtually the entire past century,
and the link between CVD and dyslipidemia
is well established.1 In particular, attention
has focused on elevations in low-density
lipoprotein cholesterol (LDL-C) as the lipid
abnormality most directly implicated as a
risk factor for CVD.
The most effective drugs for reducing
LDL-C, and thereby reducing the risk of
CVD, are the 3-hydroxy-3-methylglutaryl
coenzyme A reductase inhibitors (statins),
which act by blocking the hepatic synthesis
of cholesterol. Accordingly, statins now comprise
the largest drug category by dollar volume
in the United States ($16 billion in
2005) and the second largest category by
number of dispensed prescriptions (144 million
in 2005).2
The success of the statins has led to a
reconsideration of therapeutic goals and
means of achieving them, for the statins permit
reduction of LDL-C to levels previously
unattainable. In turn, this expanded vista of
therapeutic possibilities has led to questions
about the optimal utilization of statins. How
should individual products of this class be
selected for individual patients? What are
the risks associated with statin therapy, and
how do these risks differ among the individual
statins? How should statins be used in
patients at the highest risk of CVD? What is
the most cost-effective means of using the
statins?
With strategies for the management of
CVD and optimal utilization of statins at a
crossroads, this supplement to The American
Journal of Managed Care brings together 3
special reports of timely interest. In "An
Assessment of Statin Safety," James M.
McKenney, PharmD, addresses the concerns
about safety with statins. Since 2001, when
cerivastatin was withdrawn from the market
for reasons of safety, some nonprofessional
sources have called the statins "dangerous
drugs." However, analysis of data from the
professional literature and adverse event
reports offer a different picture. Summarizing
the findings of the National Lipid
Association Statin Safety Assessment Task
Force, Dr McKenney places the risk of
myopathy in a realistic perspective. The risk
varies among the statins and is clearly associated
with dose and exposure. At approved
dosages, the risk of serious myopathy
(including rhabdomyolysis) is well under
half of 1%; most cases of serious myopathy
have been associated with pharmacokinetic
interactions with drugs that retard statin
metabolism. Among other perceived safety
concerns, liver failure is considered a
remote risk; proteinuria occurs with all
statins but is not associated with any
increased risk of renal failure; and there is
no evidence to support concerns about neurotoxicity
and cognitive impairment with
statin therapy.
Robert M. Guthrie, MD, offers a cogent
overview in "Rising to the Challenge of
Treating High-risk Patients" of several
important recent clinical trials involving
aggressive statin therapy in patients at high
risk of CVD. Several conditions place
patients at high risk: diabetes, known coronary
heart disease, noncardiac atherosclerosis,
abdominal aneurysm, and the metabolic
syndrome (a common condition in older
patients, characterized by central obesity,
insulin resistance, glucose intolerance,
hypertension, and dyslipidemia).3 Whereas
the standard goal for LDL-C correction is
100 mg/dL or less, patients at very high risk
for CVD may benefit from a more aggressive
lipid-lowering regimen aimed at achieving
LDL-C concentrations of 70 mg/dL or less.
The conclusion from a number of important
clinical trials utilizing high-dose statins is
that the lower LDL-C goal is achievable and
is associated with significantly reduced risk
of cardiovascular events and mortality.
Given the proven ability of statins to
reduce CVD risk (and its estimated $400-
billion price tag in 20061), questions about
cost-effectiveness involve the choice of
statin rather than the rationale for statin
therapy. As reviewed by Terrance Killilea,
PharmD, and Lori Funk, PharmD, in "Cost
Efficiency and Formulary Considerations for
Statin Therapy," cost analyses focus on
achieving target LDL-C levels at the lowest
medical and pharmaceutical costs. The
overall cost of therapy is generally expected
to become more affordable as older agents go
off patent. However, differences in potency
translate to different treatment costs associated
with achieving moderate versus large
reductions in LDL-C. For patients at moderate
risk, for whom the target reduction in
LDL-C concentration is up to 40%, any of
the statins will be effective, and generic versions
can be used. However, for patients at
higher risk, who require greater reductions
in LDL-C, the greatest cost-effectiveness
may be seen with rosuvastatin or with a
fixed combination of simvastatin and the
cholesterol-absorption blocker ezetimibe.
Questions still remain about individualization
of statin therapywhich drug at
what dosage? There is no question, however,
that for now and the foreseeable future,
statins will continue to play a key role in
reducing the immense human and economic
burden of CVD.
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