Executive
Summary of the Third Report of the National Cholesterol Education Program
(NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood
Cholesterol in Adults (Adult Treatment Panel III)
Expert Panel on Detection, Evaluation, and Treatment of High Blood
Cholesterol in Adults
The Third Report of the Expert Panel on
Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult
Treatment Panel III, or ATP III) constitutes the National Cholesterol Education
Program's (NCEP's) updated clinical guidelines for cholesterol testing and
management. The full ATP III document is an evidence-based and extensively
referenced report that provides the scientific rationale for the
recommendations contained in the executive summary. ATP III builds on previous
ATP reports and expands the indications for intensive cholesterol-lowering
therapy in clinical practice. It should be noted that these guidelines are
intended to inform, not replace, the physician's clinical judgment, which must
ultimately determine the appropriate treatment for each individual.
The third ATP report updates the existing
recommendations for clinical management of high blood cholesterol. The NCEP
periodically produces ATP clinical updates as warranted by advances in the
science of cholesterol management. Each of the guideline reportsATP I, II, and IIIhas a major thrust. ATP I
outlined a strategy for primary prevention of coronary heart disease (CHD) in
persons with high levels of low-density lipoprotein (LDL) cholesterol (160 mg/dL) or those with
borderline high LDL cholesterol (130-159 mg/dL) and multiple (2+) risk factors.
ATP II affirmed the importance of this approach and added a new feature: the
intensive management of LDL cholesterol in persons with established CHD. For
patients with CHD, ATP II set a new, lower LDL cholesterol goal of 100 mg/dL. ATP III adds a
call for more intensive LDL-lowering therapy in certain groups of people, in
accord with recent clinical trial evidence, but its core is based on ATP I and
ATP II. Some of the important features shared with previous reports are shown
in Table A
in the APPENDIX.
While ATP III maintains attention to intensive
treatment of patients with CHD, its major new feature is a focus on primary
prevention in persons with multiple risk factors. Many of these persons have a
relatively high risk for CHD and will benefit from more intensive LDL-lowering
treatment than recommended in ATP II. Table 1
shows the new features of ATP III. (Note: To convert cholesterol to mmol/L,
divide values by 38.7).
Research from experimental animals, laboratory
investigations, epidemiology, and genetic forms of hypercholesterolemia
indicate that elevated LDL cholesterol is a major cause of CHD. In addition,
recent clinical trials robustly show that LDL-lowering therapy reduces risk for
CHD. For these reasons, ATP III continues to identify elevated LDL cholesterol
as the primary target of cholesterol-lowering therapy. As a result, the primary
goals of therapy and the cutpoints for initiating treatment are stated in terms
of LDL.
A basic principle of prevention is that the
intensity of risk-reduction therapy should be adjusted to a person's absolute
risk. Hence, the first step in selection of LDL-lowering therapy is to assess a
person's risk status. Risk assessment requires measurement of LDL cholesterol
as part of lipoprotein analysis and identification of accompanying risk
determinants.
In all adults aged 20 years or older, a fasting
lipoprotein profile (total cholesterol, LDL cholesterol, high-density
lipoprotein [HDL] cholesterol, and triglyceride) should be obtained once every
5 years. If the testing opportunity is nonfasting, only the values for total
cholesterol and HDL cholesterol will be usable. In such a case, if total
cholesterol is 200 mg/dL or HDL is
<40 mg/dL, a follow-up lipoprotein profile is needed for appropriate
management based on LDL. The relationship between LDL cholesterol levels and
CHD risk is continuous over a broad range of LDL levels from low to high.
Therefore, ATP III adopts the classification of LDL cholesterol levels shown in
Table 2,
which also shows the classification of total and HDL cholesterol levels.
Risk determinants in addition to LDL cholesterol
include the presence or absence of CHD, other clinical forms of atherosclerotic
disease, and the major risk factors other than LDL (Table 3).
(LDL is not counted among the risk factors in Table 3
because the purpose of counting those risk factors is to modify the treatment
of LDL.) Based on these other risk determinants, ATP III identifies 3
categories of risk that modify the goals and modalities of LDL-lowering therapy.
Table 4
defines these categories of risk and shows corresponding LDL cholesterol goals.
The category of highest risk consists of CHD and
CHD risk equivalents. The latter carry a risk for major coronary events equal
to that of established CHD, ie, >20% per 10 years (ie, more than 20 of 100
such individuals will develop CHD or have a recurrent CHD event within 10
years). CHD risk equivalents comprise:
·
Other clinical forms of
atherosclerotic disease (peripheral arterial disease, abdominal aortic
aneurysm, and symptomatic carotid artery disease)
·
Diabetes
·
Multiple risk factors
that confer a 10-year risk for CHD >20%.
Diabetes counts as a CHD risk equivalent because
it confers a high risk of new CHD within 10 years, in part because of its
frequent association with multiple risk factors. Furthermore, because persons
with diabetes who experience a myocardial infarction have an unusually high
death rate either immediately or in the long term, a more intensive prevention
strategy is warranted. Persons with CHD or CHD risk equivalents have the lowest
LDL cholesterol goal (<100 mg/dL).
The second category consists of persons with
multiple (2+) risk factors in whom 10-year risk for CHD is 20%. Risk is estimated from Framingham risk scores (see Appendix). The major risk
factors, exclusive of elevated LDL cholesterol, are used to define the presence
of multiple risk factors that modify the goals and cutpoints for LDL-lowering
treatment, and these are listed in Table 3.
The LDL cholesterol goal for persons with multiple (2+) risk factors is <130
mg/dL.
The third category consists of persons having
0-1 risk factor; with few exceptions, persons in this category have a 10-year
risk <10%. Their LDL cholesterol goal is <160 mg/dL.
Method of Risk Assessment:
Counting Major Risk Factors and Estimating 10-Year CHD Risk
Risk status in persons without clinically manifest CHD or other clinical forms
of atherosclerotic disease is determined by a 2-step procedure. First, the
number of risk factors is counted (Table 3).
Second, for persons with multiple (2+) risk factors, 10-year risk assessment is
carried out with Framingham scoring (see Appendix) to identify
individuals whose short-term (10-year) risk warrants consideration of intensive
treatment. Estimation of the 10-year CHD risk adds a step to risk assessment
beyond risk factor counting, but this step is warranted because it allows
better targeting of intensive treatment to people who will benefit from it.
When 0-1 risk factor is present, Framingham scoring is not necessary because
10-year risk rarely reaches levels for intensive intervention; a very high LDL
level in such a person may nevertheless warrant consideration of drug therapy
to reduce long-term risk. Risk factors used in Framingham scoring include age,
total cholesterol, HDL cholesterol, blood pressure, and cigarette smoking.
Total cholesterol is used for 10-year risk assessment because of a larger and
more robust Framingham database for total than for LDL cholesterol, but LDL
cholesterol is the primary target of therapy. Framingham scoring divides
persons with multiple risk factors into those with 10-year risk for CHD of
>20%, 10%-20%, and <10%. It should be noted that this 2-step sequence can
be reversed with essentially the same results. (If Framingham scoring is
carried out before risk factor counting, persons with <10% risk are then
divided into those with 2+ risk factors and 0-1 risk factor by risk factor
counting to determine the appropriate LDL goal [Table 4].)
Initial risk assessment in ATP III uses the major risk factors to define the
core risk status. Only after the core risk status has been determined should
any other risk modifiers be taken into consideration for adjusting the
therapeutic approach.
Role of Other Risk Factors in
Risk Assessment
ATP III recognizes that risk for CHD is influenced by other factors not
included among the major, independent risk factors (Table 3).
Among these are life-habit risk factors and emerging risk factors. The former
include obesity, physical inactivity, and atherogenic diet; the latter consist
of lipoprotein(a), homocysteine, prothrombotic and proinflammatory factors,
impaired fasting glucose, and evidence of subclinical atherosclerotic disease.
The life-habit risk factors are direct targets for clinical intervention but
are not used to set a lower LDL cholesterol goal of therapy. The emerging risk
factors do not categorically modify LDL cholesterol goals; however, they appear
to contribute to CHD risk to varying degrees and can have utility in selected
persons to guide intensity of risk-reduction therapy. Their presence can modulate
clinical judgment when making therapeutic decisions.
Metabolic Syndrome
Many persons have a constellation of major risk factors, life-habit risk
factors, and emerging risk factors that constitute a condition called the
metabolic syndrome. Factors characteristic of the metabolic syndrome are
abdominal obesity, atherogenic dyslipidemia (elevated triglyceride, small LDL
particles, low HDL cholesterol), raised blood pressure, insulin resistance
(with or without glucose intolerance), and prothrombotic and proinflammatory
states. ATP III recognizes the metabolic syndrome as a secondary target of
risk-reduction therapy, after the primary targetLDL cholesterol. Diagnosis and treatment of the metabolic syndrome
is described below under "Benefit Beyond LDL Lowering: The Metabolic
Syndrome as a Secondary Target of Therapy."
The Link Between Risk
Assessment and Cost-effectiveness
In ATP III, a primary aim is to match intensity of LDL-lowering therapy with
absolute risk. Everyone with elevated LDL cholesterol is treated with lifestyle
changes that are effective in lowering LDL levels. Persons at relatively high
risk are also candidates for drug treatment, which is very effective but
entails significant additional expense. The cutpoints for drug treatment are
based primarily on risk-benefit considerations: those at higher risk are likely
to get greater benefit. However, cutpoints for recommended management based on
therapeutic efficacy are checked against currently accepted standards for
cost-effectiveness. Lifestyle changes are the most cost-effective means to
reduce risk for CHD. Even so, to achieve maximal benefit, many persons will
require LDL-lowering drugs. Drug therapy is the major expense of LDL-lowering
therapy and it dominates cost-effectiveness analysis. However, the costs of
LDL-lowering drugs are currently in flux and appear to be declining. This
report recognizes that as drug prices decline it will be possible to extend
drug use to lower-risk persons and still be cost-effective. In addition, ATP
III recognizes that some persons with high long-term risk are candidates for
LDL-lowering drugs even though use of drugs may not be cost-effective by
current standards.
Primary prevention of CHD offers the greatest
opportunity for reducing the burden of CHD in the United States. The clinical
approach to primary prevention is founded on the public health approach that
calls for lifestyle changes, including (1) reduced intakes of saturated fat and
cholesterol, (2) increased physical activity, and (3) weight control, to lower
population cholesterol levels and reduce CHD risk, but the clinical approach
intensifies preventive strategies for higher-risk persons. One aim of primary
prevention is to reduce long-term risk (>10 years) as well as short-term
risk (10 years). LDL goals in
primary prevention depend on a person's absolute risk for CHD (ie, the
probability of having a CHD event in the short term or the long term)the higher the risk, the
lower the goal. Therapeutic lifestyle changes are the foundation of clinical
primary prevention. Nonetheless, some persons at higher risk because of high or
very high LDL cholesterol levels or because of multiple risk factors are
candidates for LDL-lowering drugs. Recent primary prevention trials show that
LDL-lowering drugs reduce risk for major coronary events and coronary death
even in the short term.
Recent clinical trials demonstrate that LDL-lowering
therapy reduces total mortality, coronary mortality, major coronary events,
coronary artery procedures, and stroke in persons with established CHD. As
shown in Table 2,
an LDL cholesterol level of <100 mg/dL is optimal; therefore, ATP III
specifies an LDL cholesterol level of <100 mg/dL as the goal of therapy in
secondary prevention. This goal is supported by clinical trials with both
clinical and angiographic end points and by prospective epidemiological
studies. The same goal should apply for persons with CHD risk equivalents. When
persons are hospitalized for acute coronary syndromes or coronary procedures,
lipid measures should be taken on admission or within 24 hours. These values
can guide the physician on initiation of LDL-lowering therapy before or at
discharge. Adjustment of therapy may be needed after 12 weeks.
The 2 major modalities of LDL-lowering therapy
are therapeutic lifestyle changes (TLC) and drug therapy. Both are described in
more detail later. The TLC Diet stresses reductions in saturated fat and
cholesterol intakes. When the metabolic syndrome or its associated lipid risk
factors (elevated triglyceride or low HDL cholesterol) are present, TLC also
stresses weight reduction and increased physical activity. Table 5
defines LDL cholesterol goals and cutpoints for initiation of TLC and for drug
consideration for persons with 3 categories of risk: CHD and CHD risk
equivalents; multiple (2+) risk factors (10-year risk 10%-20% and <10%); and
0-1 risk factor.
CHD and CHD Risk Equivalents
For persons with CHD and CHD risk equivalents, LDL-lowering therapy greatly
reduces risk for major coronary events and stroke and yields highly favorable
cost-effectiveness ratios. The cutpoints for initiating lifestyle and drug
therapies are shown in Table 5.
If baseline LDL cholesterol is
130 mg/dL, intensive lifestyle therapy and maximal control of other risk
factors should be started. Moreover, for most patients, an LDL-lowering drug
will be required to achieve an LDL cholesterol level of <100 mg/dL; thus an
LDL-cholesterol lowering drug can be started simultaneously with TLC to attain
the goal of therapy.
If LDL cholesterol levels are
100-129 mg/dL, either at baseline or
on LDL-lowering therapy, several therapeutic approaches are available:
·
Initiate or intensify
lifestyle and/or drug therapies specifically to lower LDL.
·
Emphasize weight
reduction and increased physical activity in persons with the metabolic
syndrome.
·
Delay use or
intensification of LDL-lowering therapies and institute treatment of other
lipid or nonlipid risk factors; consider use of other lipid-modifying drugs
(eg, nicotinic acid or fibric acid) if the patient has elevated triglyceride or
low HDL cholesterol.
If baseline LDL cholesterol is
<100 mg/dL, further LDL-lowering
therapy is not required. Patients should nonetheless be advised to follow the
TLC Diet on their own to help keep the LDL level optimal. Several clinical
trials are currently under way to assess benefit of lowering LDL cholesterol to
well below 100 mg/dL. At present, emphasis should be placed on controlling
other lipid and nonlipid risk factors and on treatment of the metabolic
syndrome, if present.
Multiple (2+) Risk Factors and
10-Year Risk of 20%
For persons with multiple (2+) risk factors and 10-year risk 20%, intensity of therapy is adjusted according to 10-year risk and
LDL cholesterol level. The treatment approach for each category is summarized
in Table 5.
Multiple (2+)
Risk Factors and a 10-Year Risk of 10%-20%
In this category, the goal for LDL cholesterol is <130 mg/dL. The
therapeutic aim is to reduce short-term risk as well as long-term risk for CHD.
If baseline LDL cholesterol is 130 mg/dL, TLC is
initiated and maintained for 3 months. If LDL remains 130 mg/dL after 3 months of TLC, consideration can be given to
starting an LDL-lowering drug to achieve the LDL goal of <130 mg/dL. Use of
LDL-lowering drugs at this risk level reduces CHD risk and is cost-effective.
If the LDL falls to less than 130 mg/dL on TLC alone, TLC can be continued
without adding drugs. In older persons (65
years), clinical judgment is required for how intensively to apply these
guidelines; a variety of factors, including concomitant illnesses, general
health status, and social issues, may influence treatment decisions and may
suggest a more conservative approach.
Multiple (2+)
Risk Factors and a 10-Year Risk of <10%
In this category, the goal for LDL cholesterol also is <130 mg/dL. The
therapeutic aim, however, is primarily to reduce longer-term risk. If baseline
LDL cholesterol is 130 mg/dL, the TLC Diet
is initiated to reduce LDL cholesterol. If LDL is <160 mg/dL on TLC alone,
it should be continued. LDL-lowering drugs generally are not recommended because
the patient is not at high short-term risk. On the other hand, if LDL
cholesterol is 160 mg/dL, drug therapy
can be considered to achieve an LDL cholesterol level of <130 mg/dL; the
primary aim is to reduce long-term risk. Cost-effectiveness is marginal, but
drug therapy can be justified to slow development of coronary atherosclerosis
and to reduce long-term risk for CHD.
0-1 Risk Factor
Most persons with 0-1 risk factor have a 10-year risk <10%. They are managed
according to Table 5.
The goal for LDL cholesterol in this risk category is <160 mg/dL. The
primary aim of therapy is to reduce long-term risk. First-line therapy is TLC.
If after 3 months of TLC the LDL cholesterol is <160 mg/dL, TLC is
continued. However, if LDL cholesterol is 160-189 mg/dL after an adequate trial
of TLC, drug therapy is optional depending on clinical judgment. Factors
favoring use of drugs include:
·
A severe single risk
factor (heavy cigarette smoking, poorly controlled hypertension, strong family
history of premature CHD, or very low HDL cholesterol)
·
Multiple life-habit risk
factors and emerging risk factors (if measured)
·
10-year risk approaching
10% (if measured; see Appendix). If LDL cholesterol
is 190 mg/dL despite TLC,
drug therapy should be considered to achieve the LDL goal of <160 mg/dL.
The purpose of using LDL-lowering drugs in persons
with 0-1 risk factor and elevated LDL cholesterol (160 mg/dL) is to slow the development of coronary atherosclerosis,
which will reduce long-term risk. This aim may conflict with cost-effectiveness
considerations; thus, clinical judgment is required in selection of persons for
drug therapy, although a strong case can be made for using drugs when LDL
cholesterol is 190 mg/dL after TLC.
For persons whose LDL cholesterol levels are
already below goal levels upon first encounter, instructions for appropriate
changes in life habits, periodic follow-up, and control of other risk factors
are needed.
ATP III recommends a multifaceted lifestyle
approach to reduce risk for CHD. This approach is designated therapeutic
lifestyle changes (TLC). Its essential features are:
·
Reduced intakes of
saturated fats (<7% of total calories) and cholesterol (<200 mg/d) (see Table 6
for overall composition of the TLC Diet)
·
Therapeutic options for
enhancing LDL lowering such as plant stanols/sterols (2 g/d) and increased
viscous (soluble) fiber (10-25 g/d)
·
Weight reduction
·
Increased physical
activity.
A model of steps in TLC is shown in Figure 1.
To initiate TLC, intakes of saturated fats and cholesterol are reduced first to
lower LDL cholesterol. To improve overall health, ATP III's TLC Diet generally
contains the recommendations embodied in the Dietary Guidelines for Americans
2000. One exception is that total fat is allowed to range from 25%-35% of total
calories provided saturated fats and trans
fatty acids are kept low. A higher intake of total fat, mostly in the form of
unsaturated fat, can help to reduce triglycerides and raise HDL cholesterol in
persons with the metabolic syndrome. In accord with the Dietary Guidelines,
moderate physical activity is encouraged. After 6 weeks, the LDL response is
determined; if the LDL cholesterol goal has not been achieved, other
therapeutic options for LDL lowering such as plant stanol/sterols and viscous
fiber can be added.
After maximum reduction of LDL cholesterol with
dietary therapy, emphasis shifts to management of the metabolic syndrome and
associated lipid risk factors. The majority of persons with these latter
abnormalities are overweight or obese and sedentary. Weight reduction therapy
for overweight or obese patients will enhance LDL lowering and will provide
other health benefits including modifying other lipid and nonlipid risk
factors. Assistance in the management of overweight and obese persons is
provided by the Clinical Guidelines on the
Identification, Evaluation, and Treatment of Overweight and Obesity in Adults
from the NHLBI Obesity Education Initiative (1998). Additional risk reduction
can be achieved by simultaneously increasing physical activity.
At all stages of dietary therapy, physicians are
encouraged to refer patients to registered dietitians or other qualified
nutritionists for medical nutrition therapy,
which is the term for the nutritional intervention and guidance provided by a
nutrition professional.
A portion of the population whose short-term or
long-term risk for CHD is high will require LDL-lowering drugs in addition to
TLC to reach the designated goal for LDL cholesterol (see Table 5).
When drugs are prescribed, attention to TLC should always be maintained and
reinforced. Currently available drugs that affect lipoprotein metabolism and
their major characteristics are listed in Table 7.
Some cholesterol-lowering agents are currently
available over-the-counter (OTC) (eg, nicotinic acid), and manufacturers of
several classes of LDL-lowering drugs (eg, statins, bile acid sequestrants)
have applied to the Food and Drug Administration (FDA) to allow these agents to
become OTC medications. At the time of publication of ATP III, the FDA has not
granted permission for OTC status for statins or bile acid sequestrants. If an
OTC cholesterol-lowering drug is or becomes available, patients should continue
to consult with their physicians about whether to initiate drug treatment,
about setting the goals of therapy, and about monitoring for therapeutic
responses and side effects.
Secondary Prevention: Drug
Therapy for CHD and CHD Risk Equivalents
For persons with CHD and CHD risk equivalents, the goal is to attain an LDL
cholesterol level of <100 mg/dL. The cutpoints for initiating lifestyle and
drug therapies are shown in Table 5.
Most patients with CHD will need LDL-lowering drug therapy. Other lipid risk
factors may also warrant consideration of drug treatment. Whether or not
lipid-modifying drugs are used, nonlipid risk factors require attention and
favorable modification.
In patients admitted to the hospital for a major
coronary event, LDL cholesterol should be measured on admission or within 24
hours. This value can be used for treatment decisions. In general, persons
hospitalized for a coronary event or procedure should be discharged on drug
therapy if the LDL cholesterol is 130
mg/dL. If the LDL is 100-129 mg/dL, clinical judgment should be used in
deciding whether to initiate drug treatment at discharge, recognizing that LDL
cholesterol levels begin to decline in the first few hours after an event and
are significantly decreased by 24 to 48 hours and may remain low for many
weeks. Thus, the initial LDL cholesterol level obtained in the hospital may be
substantially lower than is usual for the patient. Some authorities hold that
drug therapy should be initiated whenever a patient hospitalized for a
CHD-related illness is found to have an LDL cholesterol >100 mg/dL.
Initiation of drug therapy at the time of hospital discharge has 2 advantages.
First, at that time patients are particularly motivated to undertake and adhere
to risk-lowering interventions; and second, failure to initiate indicated
therapy early is one of the causes of a large "treatment gap,"
because outpatient follow-up is often less consistent and more fragmented.
LDL-Lowering Drug Therapy for
Primary Prevention
Table 5
shows the cutpoints for considering drug treatment in primary prevention. The
general approach to management of drug therapy for primary prevention is
outlined in Figure 2.
When drug therapy for primary prevention is a
consideration, the third visit of dietary therapy (see Figure 1)
will typically be the visit to initiate drug treatment. Even if drug treatment
is started, TLC should be continued. As with TLC, the first priority of drug
therapy is to achieve the goal for LDL cholesterol. For this reason, an
LDL-lowering drug should be started. The usual drug will be a statin, but
alternatives are a bile acid sequestrant or nicotinic acid. In most cases, the
statin should be started at a moderate dose. In many patients, the LDL
cholesterol goal will be achieved, and higher doses will not be necessary. The
patient's response should be evaluated about 6 weeks after starting drug
therapy. If the goal of therapy has been achieved, the current dose can be
maintained. However, if the goal has not been achieved, LDL-lowering therapy
can be intensified, either by increasing the dose of statin or by combining a
statin with a bile acid sequestrant or nicotinic acid.
After 12 weeks of drug therapy, the response to
therapy should again be assessed. If the LDL cholesterol goal is still not
achieved, consideration can be given to further intensification of drug
therapy. If the LDL goal cannot be attained by standard lipid-lowering therapy,
consideration should be given to seeking consultation from a lipid specialist.
Once the goal for LDL cholesterol has been attained, attention can turn to
other lipid risk factors and nonlipid factors. Thereafter, patients can be
monitored for response to therapy every 4 to 6 months, or more often if
considered necessary.
Evidence is accumulating that risk for CHD can
be reduced beyond LDL-lowering therapy by modification of other risk factors.
One potential secondary target of therapy is the metabolic syndrome, which
represents a constellation of lipid and nonlipid risk factors of metabolic
origin. This syndrome is closely linked to a generalized metabolic disorder
called insulin resistance in
which the normal actions of insulin are impaired. Excess body fat (particularly
abdominal obesity) and physical inactivity promote the development of insulin
resistance, but some individuals also are genetically predisposed to insulin
resistance.
The risk factors of the metabolic syndrome are
highly concordant; in aggregate they enhance risk for CHD at any given LDL
cholesterol level. For purposes of ATP III, the diagnosis of the metabolic
syndrome is made when 3 or more of the risk determinants shown in Table 8
are present. These determinants include a combination of categorical and
borderline risk factors that can be readily measured in clinical practice.
Management of the metabolic syndrome has a
2-fold objective: (1) to reduce underlying causes (ie, obesity and physical
inactivity) and (2) to treat associated nonlipid and lipid risk factors.
Management of Underlying Causes
of the Metabolic Syndrome
First-line therapies for all lipid and nonlipid risk factors associated with
the metabolic syndrome are weight reduction and increased physical activity,
which will effectively reduce all of these risk factors. Therefore, after
appropriate control of LDL cholesterol, TLC should stress weight reduction and
physical activity if the metabolic syndrome is present.
Weight
Control
In ATP III overweight and obesity are recognized as major, underlying risk
factors for CHD and identified as direct targets of intervention. Weight
reduction will enhance LDL lowering and reduce all of the risk factors of the
metabolic syndrome. The recommended approaches for reducing overweight and
obesity are contained in the clinical guidelines of the Obesity Education
Initiative.
Physical
Activity
Physical inactivity is likewise a major, underlying risk factor for CHD. It
augments the lipid and nonlipid risk factors of the metabolic syndrome. It
further may enhance risk by impairing cardiovascular fitness and coronary blood
flow. Regular physical activity reduces very low-density lipoprotein (VLDL)
levels, raises HDL cholesterol, and in some persons, lowers LDL levels. It also
can lower blood pressure, reduce insulin resistance, and favorably influence
cardiovascular function. Thus, ATP III recommends that regular physical
activity become a routine component in management of high serum cholesterol.
The evidence base for this recommendation is contained in the US Surgeon
General's Report on Physical Activity.
Specific Treatment of Lipid and
Nonlipid Risk Factors
Beyond the underlying risk factors, therapies directed against the lipid and
nonlipid risk factors of the metabolic syndrome will reduce CHD risk. These
include treatment of hypertension, use of aspirin in patients with CHD to reduce
the prothrombotic state (guidelines for aspirin use in primary prevention have
not been firmly established), and treatment of elevated triglycerides and low
HDL cholesterol as discussed below under "Management of Specific
Dyslipidemias."
Management of Specific
Dyslipidemias
Very High LDL
Cholesterol (190 mg/dL)
Persons with very high LDL cholesterol usually have genetic forms of
hypercholesterolemia: monogenic familial hypercholesterolemia, familial
defective apolipoprotein B, and polygenic hypercholesterolemia. Early detection
of these disorders through cholesterol testing in young adults is needed to
prevent premature CHD. Family testing is important to identify similarly
affected relatives. These disorders often require combined drug therapy (statin
+ bile acid sequestrant) to achieve the goals of LDL-lowering therapy.
Elevated
Serum Triglycerides
Recent meta-analyses of prospective studies indicate that elevated
triglycerides are also an independent risk factor for CHD. Factors contributing
to elevated (higher than normal) triglycerides in the general population
include obesity and overweight, physical inactivity, cigarette smoking, excess
alcohol intake, high-carbohydrate diets (>60% of energy intake), several
diseases (eg, type 2 diabetes, chronic renal failure, nephrotic syndrome),
certain drugs (eg, corticosteroids, estrogens, retinoids, higher doses of -adrenergic
blocking agents), and genetic disorders (familial combined hyperlipidemia,
familial hypertriglyceridemia, and familial dysbetalipoproteinemia).
In clinical practice, elevated serum
triglycerides are most often observed in persons with the metabolic syndrome,
although secondary or genetic factors can heighten triglyceride levels. ATP III
adopts the following classification of serum triglycerides:
·
Normal triglycerides:
<150 mg/dL
·
Borderline-high
triglycerides: 150-199 mg/dL
·
High triglycerides:
200-499 mg/dL
·
Very high triglycerides:
500 mg/dL
(To convert triglyceride values to mmol/L,
divide by 88.6.)
The finding that elevated triglycerides are an
independent CHD risk factor suggests that some triglyceride-rich lipoproteins
are atherogenic. The latter are partially degraded VLDL, commonly called remnant lipoproteins. In clinical
practice, VLDL cholesterol is the most readily available measure of atherogenic
remnant lipoproteins. Thus, VLDL cholesterol can be a target of
cholesterol-lowering therapy. ATP III identifies the sum of LDL + VLDL
cholesterol (termed non-HDL cholesterol
[total cholesterol - HDL cholesterol]) as a secondary target of therapy in
persons with high triglycerides (200
mg/dL). The goal for non-HDL cholesterol in persons with high serum
triglycerides can be set at 30 mg/dL higher than that for LDL cholesterol (Table 9)
on the premise that a VLDL cholesterol level 30 mg/dL
is normal.
The treatment strategy for elevated
triglycerides depends on the causes of the elevation and its severity. For all
persons with borderline high or high triglycerides, the primary aim of therapy
is to achieve the target goal for LDL cholesterol. When triglycerides are
borderline high (150-199 mg/dL), emphasis should also be placed on weight
reduction and increased physical activity. For high triglycerides (200-499
mg/dL), non-HDL cholesterol becomes a secondary target of therapy. Aside from
weight reduction and increased physical activity, drug therapy can be
considered in high-risk persons to achieve the non-HDL cholesterol goal. There
are 2 approaches to drug therapy. First, the non-HDL cholesterol goal can be
achieved by intensifying therapy with an LDL-lowering drug; second, nicotinic
acid or fibrate can be added, if used with appropriate caution, to achieve the
non-HDL cholesterol goal by further lowering VLDL cholesterol. In rare cases in
which triglycerides are very high (500
mg/dL), the initial aim of therapy is to prevent acute pancreatitis through
triglyceride lowering. This approach requires very low-fat diets (15% of calorie intake),
weight reduction, increased physical activity, and usually a
triglyceride-lowering drug (fibrate or nicotinic acid). Only after triglyceride
levels have been lowered to <500 mg/dL should attention turn to LDL lowering
to reduce risk for CHD.
Low HDL
Cholesterol
Low HDL cholesterol is a strong independent predictor of CHD. In ATP III, low
HDL cholesterol is defined categorically as a level <40 mg/dL, a change from
the level of <35 mg/dL in ATP II. In the present guidelines, low HDL
cholesterol both modifies the goal for LDL-lowering therapy and is used as a
risk factor to estimate 10-year risk for CHD.
Low HDL cholesterol levels have several causes,
many of which are associated with insulin resistance, ie, elevated
triglycerides, overweight and obesity, physical inactivity, and type 2
diabetes. Other causes are cigarette smoking, very high carbohydrate intakes
(>60% of calories), and certain drugs (eg, -blockers,
anabolic steroids, progestational agents).
ATP III does not specify a goal for HDL raising.
Although clinical trial results suggest that raising HDL will reduce risk, the
evidence is insufficient to specify a goal of therapy. Furthermore, currently
available drugs do not robustly raise HDL cholesterol. Nonetheless, a low HDL
should receive clinical attention and management according to the following
sequence. In all persons with low HDL cholesterol, the primary target of
therapy is LDL cholesterol; ATP III guidelines should be followed to achieve
the LDL cholesterol goal. Second, after the LDL goal has been reached, emphasis
shifts to weight reduction and increased physical activity (when the metabolic
syndrome is present). When a low HDL cholesterol is associated with high
triglycerides (200-499 mg/dL), secondary priority goes to achieving the non-HDL
cholesterol goal, as outlined earlier. Also, if triglycerides are <200 mg/dL
(isolated low HDL cholesterol), drugs for HDL raising (fibrates or nicotinic
acid) can be considered; however, treatment for isolated low HDL is mostly
reserved for persons with CHD and CHD risk equivalents.
Diabetic
Dyslipidemia
This disorder is essentially atherogenic dyslipidemia in persons with type 2
diabetes. Although elevated triglycerides, low HDL cholesterol, or both are
common in persons with diabetes, clinical trial results support the identification
of LDL cholesterol as the primary target of therapy, as it is in those without
diabetes. Since diabetes is designated a CHD risk equivalent in ATP III, the
LDL cholesterol goal of therapy for most persons with diabetes will be <100
mg/dL. Furthermore, when LDL cholesterol is 130
mg/dL, most persons with diabetes will require initiation of LDL-lowering drugs
simultaneously with TLC to achieve the LDL goal. When LDL cholesterol levels
are in the range of 100-129 mg/dL at baseline or on treatment, several
therapeutic options are available: increasing intensity of LDL-lowering
therapy, adding a drug to modify atherogenic dyslipidemia (fibrate or nicotinic
acid), or intensifying control of other risk factors including hyperglycemia.
When triglyceride levels are 200 mg/dL, non-HDL
cholesterol becomes a secondary target of cholesterol-lowering therapy. Several
ongoing clinical trials (eg, Antihypertensive and Lipid Lowering Heart Attack
Trial [ALLHAT]) will better quantify the magnitude of the benefit of
LDL-lowering treatment in older individuals with diabetes. In older persons (65 years) with diabetes
but no additional CHD risk factors other than age, clinical judgment is
required for how intensively to apply these guidelines. A variety of factors,
including concomitant illnesses, general health status, and social issues, may
influence treatment decisions and may suggest a more conservative approach.
Special Considerations for
Different Population Groups
Middle-Aged Men (35-65
Years)
In general, men have a higher risk for CHD than do women. Middle-aged men in
particular have a high prevalence of the major risk factors and are predisposed
to abdominal obesity and the metabolic syndrome. A sizable fraction of all CHD
in men occurs in middle age. Thus, many middle-aged men carry a relatively high
risk for CHD, and for those who do, intensive LDL-lowering therapy is needed.
Women Aged
45-75 Years
In women, onset of CHD generally is delayed by some 10 to 15 years compared
with that in men; thus, most CHD in women occurs after age 65 years. All risk
factors contribute to CHD in women, and most premature CHD in women (<65
years) occurs in those with multiple risk factors and the metabolic syndrome.
Despite the previous belief that the sex difference in risk for CHD reflects a
protective effect of estrogen in women, recent secondary and primary prevention
trials cast doubt on the use of hormone replacement therapy to reduce CHD risk
in postmenopausal women. In contrast, the favorable effects of statin therapy
in women in clinical trials make a cholesterol-lowering drug preferable to
hormone replacement therapy for CHD risk reduction. Women should be treated similarly
to men for secondary prevention. For primary prevention, ATP III's general
approach is similarly applicable for women and men. However, the later onset of
CHD for women in general should be factored into clinical decisions about use
of cholesterol-lowering drugs.
Older Adults
(Men 65 Years and Women 75 Years)
Overall, most new CHD events and most coronary deaths occur in older persons (65 years). A high level
of LDL cholesterol and low HDL cholesterol still carry predictive power for the
development of CHD in older persons. Nevertheless, the finding of advanced
subclinical atherosclerosis by noninvasive testing can be helpful for
confirming the presence of high risk in older persons. Secondary prevention
trials with statins have included a sizable number of older persons, mostly in
the age range of 65 to 75 years. In these trials, older persons showed
significant risk reduction with statin therapy. Thus, no hard-and-fast age
restrictions appear necessary when selecting persons with established CHD for
LDL-lowering therapy. For primary prevention, TLC is the first line of therapy
for older persons. However, LDL-lowering drugs can also be considered when
older persons are at higher risk because of multiple risk factors or advanced
subclinical atherosclerosis.
Younger
Adults (Men 20-35 Years; Women 20-45 Years)
In this age group, CHD is rare except in those with severe risk factors, eg,
familial hypercholesterolemia, heavy cigarette smoking, or diabetes. Even
though clinical CHD is relatively rare in young adults, coronary
atherosclerosis in its early stages may progress rapidly. The rate of
development of coronary atherosclerosis earlier in life correlates with the
major risk factors. In particular, long-term prospective studies reveal that
elevated serum cholesterol detected in young adulthood predicts a higher rate
of premature CHD in middle age. Thus, risk factor identification in young
adults is an important aim for long-term prevention. The combination of early
detection and early intervention on elevated LDL cholesterol with life-habit
changes offers the opportunity for delaying or preventing onset of CHD later in
life. For young adults with LDL cholesterol levels of 130 mg/dL, TLC should be instituted and emphasized. Particular
attention should be given to young men who smoke and have a high LDL cholesterol
(160-189 mg/dL); they may be candidates for LDL-lowering drugs. When young
adults have very high LDL cholesterol levels (190 mg/dL),
drug therapy should be considered, as in other adults. Those with severe
genetic forms of hypercholesterolemia may require LDL-lowering drugs in
combination (eg, statin + bile acid sequestrant).
Racial and
Ethnic Groups
African Americans have the highest overall CHD mortality rate and the highest
out-of-hospital coronary death rates of any ethnic group in the United States,
particularly at younger ages. Although the reasons for the excess CHD mortality
among African Americans have not been fully elucidated, it can be accounted
for, at least in part, by the high prevalence of coronary risk factors.
Hypertension, left ventricular hypertrophy, diabetes mellitus, cigarette
smoking, obesity, physical inactivity, and multiple CHD risk factors all occur
more frequently in African Americans than in whites. Other ethnic groups and
minority populations in the United States include Hispanics, Native Americans,
Asian and Pacific Islanders, and South Asians. Although limited data suggest
that racial and ethnic groups vary somewhat in baseline risk for CHD, this
evidence did not appear sufficient to lead the ATP III panel to modify general
recommendations for cholesterol management in these populations.
Adherence to the ATP III guidelines by both
patients and providers is a key to approximating the magnitude of the benefits
demonstrated in clinical trials of cholesterol lowering. Adherence issues have
to be addressed to attain the highest possible levels of CHD risk reduction.
Thus, ATP III recommends the use of state-of-the-art multidisciplinary methods
targeting the patient, clinicians, and health delivery systems to achieve the
full population effectiveness of the guidelines for primary and secondary
prevention (Table 10).
Author/Article Information
Corresponding Author and Reprints:
James I. Cleeman, MD, National Cholesterol Education Program, National Heart,
Lung, and Blood Institute (NHLBI), 31 Center Dr, Room 4A16, MSC 2480, Bethesda,
MD 20892-2480 (e-mail: [log in to unmask]).
The Full Report of ATP III is available online on the NHLBI Web site at http://www.nhlbi.nih.gov.
National
Cholesterol Education Program Expert Panel on Detection, Evaluation, and
Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) Members: Scott M. Grundy, MD, PhD (Chair of the panel), Diane Becker,
RN, MPH, ScD, Luther T. Clark, MD, Richard S. Cooper, MD, Margo A. Denke, MD,
Wm. James Howard, MD, Donald B. Hunninghake, MD, D. Roger Illingworth, MD,
PhD, Russell V. Luepker, MD, MS, Patrick McBride, MD, MPH, James M. McKenney,
PharmD, Richard C. Pasternak, MD, Neil J. Stone, MD, Linda Van Horn, PhD, RD Ex-officio Members: H. Bryan Brewer, Jr, MD, James I. Cleeman, MD (Executive
Director of the panel), Nancy D. Ernst, PhD, RD, David Gordon, MD, PhD,
Daniel Levy, MD, Basil Rifkind, MD, Jacques E. Rossouw, MD, Peter Savage, MD Consultants: Steven M. Haffner, MD, David G. Orloff, MD, Michael A.
Proschan, PhD, J. Sanford Schwartz, MD, Christopher T. Sempos, PhD Staff: Susan T. Shero, RN, MS, Elaine Z. Murray |
Any person with elevated LDL cholesterol or
other form of hyperlipidemia should undergo clinical or laboratory assessment
to rule out secondary dyslipidemia before initiation of lipid-lowering
therapy. Causes of secondary dyslipidemia include: ·
Diabetes ·
Hypothyroidism ·
Obstructive liver
disease ·
Chronic renal failure ·
Drugs that increase
LDL cholesterol and decrease HDL cholesterol (progestins, anabolic steroids,
and corticosteroids). Once secondary causes have been excluded or,
if appropriate, treated, the goals for LDL-lowering therapy in primary
prevention are established according to a person's risk category (Table 4). |
Financial Disclosure: Dr Grundy has received honoraria from Merck, Pfizer, Sankyo,
Bayer, and Bristol-Myers Squibb. Dr Hunninghake has current grants from Merck,
Pfizer, Kos Pharmaceuticals, Schering Plough, Wyeth Ayerst, Sankyo, Bayer,
AstraZeneca, Bristol-Myers Squibb, and G. D. Searle; he has also received
consulting honoraria from Merck, Pfizer, Kos Pharmaceuticals, Sankyo,
AstraZeneca, and Bayer. Dr McBride has received grants and/or research support
from Pfizer, Merck, Parke-Davis, and AstraZeneca; has served as a consultant
for Kos Pharmaceuticals, Abbott, and Merck; and has received honoraria from
Abbott, Bristol-Myers Squibb, Novartis, Merck, Kos Pharmaceuticals,
Parke-Davis, Pfizer, and DuPont. Dr Pasternak has served as a consultant for
and received honoraria from Merck, Pfizer, and Kos Pharmaceuticals, and has
received grants from Merck and Pfizer. Dr Stone has served as a consultant
and/or received honoraria for lectures from Abbott, Bayer, Bristol-Myers
Squibb, Kos Pharmaceuticals, Merck, Novartis, Parke-Davis/Pfizer, and Sankyo.
Dr Schwartz has served as a consultant for and/or conducted research funded by
Bristol-Myers Squibb, AstraZeneca, Merck, Johnson & Johnson-Merck, and
Pfizer.
Executive Committee Liaison to
the Panel: Stephen Havas, MD, MPH,
MS
Reviewers of the Full Report of
ATP III: Eugene Braunwald, MD,
W. Virgil Brown, MD, Alan Chait, MD, James E. Dalen, MD, Valentin Fuster, MD,
PhD, Henry N. Ginsberg, MD, Antonio M. Gotto, MD, DPhil, Ronald M. Krauss, MD,
John C. LaRosa, MD, Thomas H. Lee, Jr, MD, Linda Meyers, PhD, Michael Newman,
MD, Thomas Pearson, MD, PhD, Daniel J. Rader, MD, Frank M. Sacks, MD, Ernst J.
Schaefer, MD, Sheldon G. Sheps, MD, Lynn A. Smaha, MD, PhD, Sidney C. Smith,
Jr, MD, Jeremiah Stamler, MD, Daniel Steinberg, MD, PhD, Nanette K. Wenger, MD
National Cholesterol Education
Program Coordinating Committee: The
Third Report of the Expert Panel on Detection, Evaluation, and Treatment of
High Blood Cholesterol in Adults was approved by the National Cholesterol
Education Program Coordinating Committee, which comprises the following
organizational representatives:
Member Organizations: National Heart, Lung, and Blood Institute:
Claude Lenfant, MD (Chair), James I. Cleeman, MD (Coordinator); American Academy of Family Physicians:
Theodore G. Ganiats, MD; American Academy of
Insurance Medicine: Gary Graham, MD; American Academy of Pediatrics: Ronald E. Kleinman, MD; American Association of Occupational Health Nurses:
Pamela Hixon, BSN, RN, COHN-S; American
College of Cardiology: Richard C. Pasternak, MD; American College of Chest Physicians:
Gerald T. Gau, MD, American College of
Nutrition: Harry Preuss, MD; American
College of Obstetricians and Gynecologists: Thomas C. Peng, MD; American College of Occupational and Environmental
Medicine: Ruth Ann Jordan, MD; American
College of Preventive Medicine: Lewis H. Kuller, MD, DrPH; American Diabetes Association, Inc: Alan
J. Garber, MD, PhD; American Dietetic
Association: Linda Van Horn, PhD, RD; American Heart Association: Scott M. Grundy, MD, PhD; American Hospital Association: Sandra
Cornett, RN, PhD; American Medical
Association: Yank D. Coble, Jr, MD; American
Nurses Association: to be named; American
Osteopathic Association: Michael Clearfield, DO; American Pharmaceutical Association: James
M. McKenney, PharmD; American Public Health
Association: Stephen Havas, MD, MPH, MS; American Red Cross: Donald Vardell, MS; Association of Black Cardiologists: Karol
Watson, MD, PhD; Association of State and
Territorial Health Officials: Joanne Mitten, MHE; Citizens for Public Action on Blood Pressure and
Cholesterol, Inc: Gerald J. Wilson, MA, MBA; National Black Nurses Association, Inc:
Linda Burnes-Bolton, DrPH, RN, MSN; National
Medical Association: Luther T. Clark, MD; Society for Nutrition Education: Darlene Lansing, MPH, RD; Society for Public Health Education:
Donald O. Fedder, DrPH, MPH.
Associate Member Organization: American Association of Office Nurses:
Joyce Logan.
Federal Agencies: NHLBI Ad Hoc Committee on Minority Populations:
Yvonne L. Bronner, ScD, RD, LD; Agency for
Healthcare Research and Quality: Francis D. Chesley, Jr, MD; Centers for Disease Control and Prevention:
Wayne Giles, MD, MPH; Coordinating Committee
for the Community Demonstration Studies: Thomas M. Lasater, PhD; Department of Agriculture: Alanna
Moshfegh, MS, RD; Department of Defense:
Col Robert Dana Bradshaw, MD, MPH; Food and
Drug Administration: Elizabeth Yetley, PhD; Health Resources and Services Administration:
Celia Hayes, MPH, RD; National Cancer
Institute: Carolyn Clifford, PhD; National
Center for Health Statistics: Clifford Johnson, MPH; Office of Disease Prevention and Health Promotion:
Elizabeth Castro, PhD; Department of
Veterans Affairs: Pamela Steele, MD.
Shared Features of ATP III and
ATP II
Adult Treatment Panel (ATP) III shares a set of
core features with ATP II, shown in Table A.
Estimating 10-Year Risk for Men
and Women
Risk assessment for determining the 10-year risk
for developing CHD is carried out using Framingham risk scoring (Table B1
for men and Table B2
for women). The risk factors included in the Framingham calculation of 10-year
risk are age, total cholesterol, HDL cholesterol, systolic blood pressure,
treatment for hypertension, and cigarette smoking. The first step is to
calculate the number of points for each risk factor. For initial assessment,
values for total cholesterol and HDL cholesterol are required. Because of a
larger database, Framingham estimates are more robust for total cholesterol
than for LDL cholesterol. Note, however, that the LDL cholesterol level remains
the primary target of therapy. Total cholesterol and HDL cholesterol values
should be the average of at least 2 measurements obtained from lipoprotein
analysis. The blood pressure value used is that obtained at the time of
assessment, regardless of whether the person is on antihypertensive therapy.
However, if the person is on antihypertensive treatment, an extra point is
added beyond points for the blood pressure reading because treated hypertension
carries residual risk (Table B1
and Table B2).
The average of several blood pressure measurements, as recommended by the Joint
National Committee (JNC), is needed for an accurate measure of baseline blood
pressure. The designation "smoker" means any cigarette smoking in the
past month. The total risk score sums the points for each risk factor. The
10-year risk for myocardial infarction and coronary death (hard CHD) is
estimated from total points, and the person is categorized according to
absolute 10-year risk as indicated above (see Table 5).
Edward E.
Rylander, M.D.
Diplomat American
Board of Family Practice.
Diplomat American
Board of Palliative Medicine.