Lipid Control in the Management of Type 2 Diabetes Mellitus:
A Clinical Practice Guideline from the American College of Physicians
Vincenza Snow, MD; Mark D. Aronson, MD; E. Rodney Hornbake, MD; Christel Mottur-Pilson, PhD; and Kevin B. Weiss, MD, for the Clinical
Efficacy Assessment Subcommittee of the American College of Physicians*
In an effort to provide internists and other primary care physicians
with effective management strategies for diabetes care, the Clin-
ical Efficacy Assessment Subcommittee (CEAS) of the American
College of Physicians (ACP) decided to develop guidelines on the
management of dyslipidemia, particularly hypercholesterolemia, in
people with type 2 diabetes mellitus. The CEAS commissioned a
systematic review of the currently available evidence on the man-
agement of lipids in type 2 diabetes mellitus. The evidence review
is presented in a background paper in this issue. On the basis of
this systematic review, the CEAS developed recommendations that
the ACP Board of Regents then approved as policy.
The target audience for this guideline is all clinicians who
care for patients with type 2 diabetes. The target patient popula-
tion is all persons with type 2 diabetes, including those who
already have some form of microvascular complication and, of
particular importance, premenopausal women. The recommenda-
tions are as follows.
Recommendation 1: Lipid-lowering therapy should be used
for secondary prevention of cardiovascular mortality and morbidity
for all patients (both men and women) with known coronary
artery disease and type 2 diabetes.
Recommendation 2: Statins should be used for primary pre-
vention against macrovascular complications in patients (both
men and women) with type 2 diabetes and other cardiovascular
risk factors.
Recommendation 3: Once lipid-lowering therapy is initiated,
patients with type 2 diabetes mellitus should be taking at least
moderate doses of a statin.
Recommendation 4: For those patients with type 2 diabetes
who are taking statins, routine monitoring of liver function tests
or muscle enzymes is not recommended except in specific circum-
stances.
Ann Intern Med. 2004;140:644-649. www.annals.org
For author affiliations, see end of text.
See related article on pp 650-658.
Diabetes mellitus is a leading cause of morbidity andmortality in the United States. Type 2 diabetes mel-
litus is most common (90% to 95% of persons with dia-
betes) and affects older adults, particularly those older than
50 years of age. An estimated 16 million Americans have
type 2 diabetes, and up to 800 000 new diagnoses are
made each year (1, 2). Most adverse diabetes outcomes are
a result of vascular complications, which are generally clas-
sified as microvascular (such as retinopathy, nephropathy,
and neuropathy, although the latter may not be entirely a
microvascular disease) or macrovascular (such as coronary
artery disease, cerebrovascular disease, and peripheral vas-
cular disease).
To prevent or diminish the progression of microvas-
cular and macrovascular complications, recommended
diabetes management necessarily encompasses both meta-
bolic control and control of cardiovascular risk factors (3–
5). The need for good glycemic control is supported by the
Diabetes Control and Complications Trial (6) in type 1
diabetes and, more recently, the United Kingdom Prospec-
tive Diabetes Study in type 2 diabetes (7). In these studies,
tight blood sugar control reduced microvascular complica-
tions such as nephropathy and retinopathy but had little
effect on macrovascular outcomes. Up to 80% of patients
with type 2 diabetes will develop or die of macrovascular
disease, underscoring the importance of preventing macro-
vascular complications.
In an effort to provide internists and other primary
care physicians with effective management strategies for
diabetes care, the American College of Physicians (ACP)
decided to develop guidelines on the management of dys-
lipidemia, particularly hypercholesterolemia, in people
with type 2 diabetes. A previous College guideline ad-
dressed the critical role of tight blood pressure control in
type 2 diabetes mellitus (8, 9). The target audience for this
guideline is all clinicians who care for patients with type 2
diabetes. The target patient population is all persons with
type 2 diabetes, including those who already have some
form of microvascular complication and, of particular im-
portance, premenopausal women. In this guideline we ad-
dress the following questions.
1. What are the benefits of tight lipid control for both
primary and secondary prevention in type 2 diabetes?
2. What is the evidence for treating to certain target
levels of low-density lipoprotein (LDL) cholesterol for pa-
tients with type 2 diabetes?
3. Are certain lipid-lowering agents more effective or
beneficial in patients with type 2 diabetes?
This guideline is based on the systematic review of the
evidence presented in the background paper by Vijan and
*This paper, written by Vincenza Snow, MD; Mark D. Aronson, MD; E. Rodney Hornbake, MD; Christel Mottur-Pilson, PhD; and Kevin B. Weiss, MD, was developed by the Clinical Efficacy
Assessment Subcommittee of the American College of Physicians (ACP): Kevin Weiss, MD (Chair); Mark Aronson, MD; Patricia Barry, MD; Virginia Collier, MD; J. Thomas Cross Jr., MD; Nick
Fitterman, MD; E. Rodney Hornbake, MD; Douglas K. Owens, MD; and Katherine D. Sherif, MD. Approved by the ACP Board of Regents in July 2003.
Annals of Internal Medicine encourages readers to copy and distribute this paper, providing such distribution is not for profit. Commercial distribution is not permitted without the express permission
of the publisher.
Clinical Guidelines
644 © 2004 American College of Physicians
colleagues in this issue (10). When Vijan and colleagues
analyzed benefit or effectiveness, only studies that mea-
sured clinical end points were included. The major clinical
end points in trials used to support the evidence for these
guidelines were all-cause mortality, cardiovascular mortal-
ity, and cardiovascular events (that is, myocardial infarc-
tion, stroke, and cardiovascular mortality). No studies of
lipid-lowering therapy have been conducted solely in pa-
tients with diabetes. Moreover, many trials excluded pa-
tients with diabetes. The sample sizes of participants with
diabetes were often small, and many studies reported re-
sults only for the combined groups. Thus, the reports in-
cluded in this review are of the subgroup analyses for stud-
ies that included patients with diabetes.
The review was stratified into 2 categories. The first
category evaluated the effects of lipid management in pri-
mary prevention (that is, in patients without known coro-
nary disease). The second category evaluated the effects in
secondary prevention (that is, in patients with established
coronary disease). A total of 12 lipid-lowering studies pre-
sented diabetes-specific data and reported clinical out-
comes. A discussion of this evidence follows (for a more
detailed description of methodology, refer to the back-
ground paper by Vijan and colleagues [10]).
PRIMARY PREVENTION
Six studies of primary prevention in patients with di-
abetes were identified. The Air Force Coronary Atheroscle-
rosis Prevention Study/Texas Coronary Atherosclerosis
Prevention Study (AFCAPS/TexCAPS) randomly assigned
patients with average cholesterol levels and lower than av-
erage high-density lipoprotein (HDL) cholesterol levels to
lovastatin, 20 to 40 mg/d, or placebo (in addition to a
low-fat and low-cholesterol diet) for an average follow-up
of 5.2 years (11). Based on data from the Third National
Health and Nutrition Examination Survey, mean total
cholesterol level was 5.72 mmol/L (221 mg/dL), mean
LDL cholesterol level was 3.88 mmol/L (150 mg/dL), and
mean HDL cholesterol level was 0.93 mmol/L (36 mg/dL)
for men and 1.03 mmol/L (40 mg/dL) for women. One
hundred fifty-five patients had diabetes. Lovastatin therapy
led to a relative risk of 0.56 (95% CI, 0.17 to 1.92) for any
atherosclerotic cardiovascular event (first fatal or nonfatal
myocardial infarction, unstable angina, or sudden cardiac
death) and an absolute risk reduction of 0.04 (CI, �0.04
to 0.12), neither of which was statistically significant. The
mean LDL cholesterol level at the end of the study was
2.97 mmol/L (115 mg/dL), and the mean HDL choles-
terol level was 1.00 mmol/L (39 mg/dL).
The Antihypertensive and Lipid-Lowering Treatment
to Prevent Heart Attack Trial–Lipid-Lowering Trial
(ALLHAT-LLT) randomly assigned patients 55 years of
age and older who had hypertension and at least one other
coronary heart disease (CHD) risk factor to pravastatin, 40
mg/d, or placebo (12). In the subgroup analysis of 3638
patients with type 2 diabetes, the relative risk for CHD
events was 0.89 (CI, 0.71 to 1.10); the absolute risk reduc-
tion was not reported. This study has been criticized be-
cause of the smaller difference between LDL cholesterol
levels in the control and intervention groups, which is
probably due in part to contamination of the control group
by publication of several other lipid-lowering trials during
the study.
The Helsinki Heart Study (13) randomly assigned
men age 40 to 55 years with elevated non-HDL cholesterol
levels to gemfibrozil, 600 mg 2 times per day, or placebo.
The mean total cholesterol level was 7.5 mmol/L (290
mg/dL), and mean HDL cholesterol level was 1.23
mmol/L (47.6 mg/dL). In the 135 patients with diabetes,
the incidence of CHD at 5 years was 3.4% in the gem-
fibrozil group and 10.5% in the placebo group. The rela-
tive risk was 0.32 (CI, 0.07 to 1.46), and the absolute risk
reduction was 0.07 (CI, �0.01 to 0.15). None of these
differences were statistically significant (14).
The Heart Protection Study (HPS) included data on
both primary and secondary prevention in patients with
diabetes who were at high risk for cardiovascular disease
(15). The objective of this study was to examine the effects
of therapy to lower LDL cholesterol level across a broad
range of lipid levels and risk factors. The HPS enrolled
patients 40 to 80 years of age with nonfasting total choles-
terol levels of at least 3.49 mmol/L (�135 mg/dL). In the
primary prevention group, 3982 patients had diabetes.
Treatment with simvastatin, 40 mg, led to reduced risks
for CHD events (relative risk, 0.74 [CI, 0.64 to 0.85];
absolute risk reduction, 0.05 [CI, 0.03 to 0.07]).
The Prospective Study of Pravastatin in the Elderly at
Risk (PROSPER) randomly assigned men and women 70
to 82 years of age with a history of cerebral or peripheral
vascular disease or risk factors for such disease (such as
smoking, hypertension, and diabetes) to pravastatin, 40
mg/d, or placebo (16). In the primary prevention group,
396 patients had diabetes. In these patients, treatment with
pravastatin led to a trend toward harm (relative risk, 1.23
[CI, 0.77 to 1.95]; absolute risk reduction, �0.03 [CI,
�0.10 to 0.04]). The interaction between diabetes and the
treatment group was statistically significant, suggesting that
patients with diabetes did substantially worse than those
without diabetes.
The Anglo-Scandinavian Cardiac Outcome Trial–
Lipid Lowering Arm (ASCOT-LLA) randomly assigned
patients age 40 to 79 years without CHD but with hyper-
tension and at least 3 other cardiovascular risk factors (left
ventricular hypertrophy, other electrocardiographic abnor-
malities, type 2 diabetes, peripheral arterial disease, previ-
ous stroke or transient ischemic attack, male sex, age� 55
years, microalbuminuria, proteinuria, smoking, ratio of
plasma total to HDL cholesterol of 6 or higher, or family
history of premature CHD) to atorvastatin, 10 mg/d, or
placebo (17). The diabetes subgroup, 2532 patients who
had hypertension and at least 2 other risk factors, had low
Clinical GuidelinesLipid Control in the Management of Type 2 Diabetes Mellitus
www.annals.org 20 April 2004 Annals of Internal Medicine Volume 140 • Number 8 645
event rates of 3.6% in the control group and 3.0% in the
intervention group. Thus, lipid-lowering treatment, with a
relative risk of 0.84 (CI, 0.55 to 1.29) and an absolute risk
reduction of 0.006 (CI, �0.008 to 0.019), did not lead to
statistically significant improvements in the diabetes group.
SECONDARY PREVENTION
Eight trials reported on secondary prevention in pa-
tients with diabetes. The first, the Scandinavian Simvasta-
tin Survival Study (4S), randomly assigned patients with
coronary disease to simvastatin, 20 mg, or placebo (18). In
a secondary analysis of the 202 patients with diabetes, sim-
vastatin led to large benefits (relative risk for cardiovascular
events, 0.50 [CI, 0.33 to 0.76]; absolute risk reduction,
0.23 [CI, 0.10 to 0.35]). Of note is the relatively high
event rate in the control group (45%) compared with those
seen in other trials.
The Cholesterol and Recurrent Events (CARE) trial
randomly assigned patients with previous myocardial in-
farction to pravastatin, 40 mg/d, or placebo (19). Pravasta-
tin improved CHD outcomes in the 586 patients with
diabetes (relative risk for cardiovascular events, 0.78 [CI,
0.62 to 0.99]; absolute risk reduction, 0.08 [CI, 0.01 to
0.16]). Results were reported as stratified by baseline LDL
cholesterol levels and showed that for the overall study
sample, those with baseline levels below 3.23 mmol/L
(�125 mg/dL) did not benefit from lipid-lowering therapy
while those with LDL cholesterol levels of at least 3.23
mmol/L (�125 mg/dL) benefited substantially. The small
sample size precluded a similar stratified analysis in the
patients with diabetes.
The HPS examined the impact of lipid-lowering ther-
apy in secondary prevention in 20 536 patients with coro-
nary disease, other occlusive arterial disease, or diabetes
(15). Treatment was with simvastatin, 40 mg/d, or pla-
cebo. There was no dose adjustment by baseline lipid lev-
els. Among patients with diabetes, the relative risk for any
cardiovascular event was 0.89 (CI, 0.79 to 1.00) in the
simvastatin group, and the absolute risk reduction was
0.04 (CI, 0.00 to 0.09).
The Long-Term Intervention with Pravastatin in Isch-
emic Disease (LIPID) trial randomly assigned patients with
known heart disease to pravastatin, 40 mg/d, or placebo
(20). In the subgroup of 782 patients with diabetes, the
relative risk for a cardiovascular event was 0.84 (CI, 0.64 to
1.11) and the absolute risk reduction was 0.04 (CI, �0.02
to 0.09). Neither of these was statistically significant.
The Lescol Intervention Prevention Study (LIPS) was
a trial conducted in patients who had undergone percuta-
neous coronary intervention (21). Researchers randomly
assigned patients to fluvastatin, 80 mg/d, or placebo. In the
202 patients with type 2 diabetes, fluvastatin was effective
in preventing CHD events (relative risk, 0.53 [CI, 0.29 to
0.97]; absolute risk reduction, 0.16 [CI, 0.03 to 0.29]).
The Post–Coronary Artery Bypass Graft (Post-CABG)
trial randomly assigned patients who had undergone coro-
nary artery bypass grafting to “aggressive” LDL cholesterol
targets of 1.55 to 2.20 mmol/L (60 to 85 mg/dL) or “mod-
erate” targets of 3.36 to 3.62 mmol/L (130 to 140 mg/dL)
(22). Lovastatin was used as the primary agent, and cho-
lestyramine was added if goals were not achieved. Most
patients did not reach the intensive goal; the mean
achieved LDL cholesterol level ranged from 2.40 to 2.51
mmol/L (93 to 97 mg/dL) over the course of the study.
One hundred sixteen patients in the trial had diabetes.
Aggressive LDL cholesterol lowering led to a relative risk of
0.53 (CI, 0.18 to 1.60) and an absolute risk reduction of
0.12 (CI, �0.03 to 0.27). Neither of these was statistically
significant.
The Veterans Administration High-Density Lipopro-
tein Cholesterol Intervention Trial (VA-HIT) was a sec-
ondary prevention study whose intervention and goal were
different from the others (23). This study targeted patients
with the low-HDL, low-LDL syndrome (HDL cholesterol
level � 1.03 mmol/L 40 mg/dL]; LDL cholesterol level
� 3.62 mmol/L [�140 mg/dL]), which is very common
in patients with diabetes or insulin resistance. The study
enrolled men younger than 74 years of age who had doc-
umented coronary disease. Treatment was with gemfibro-
zil, 1200 mg/d, or placebo. In the diabetes subgroup (n �
627), the relative risk for cardiovascular events was 0.76
(CI, 0.57 to 1.01) and the absolute risk reduction was 0.08
(CI, 0.01 to 0.15). In a follow-up article, inclusion of pa-
tients with undiagnosed diabetes in this subgroup reduced
the risks further (relative risk, 0.68; absolute risk reduction,
10%) (24). Of interest, these analyses also suggest that
much of the benefit in this study was in patients with
diabetes and that fasting plasma insulin levels were a major
indicator of the success of therapy.
META-ANALYSIS
Vijan and colleagues conducted a meta-analysis of the
trial results for the diabetes subgroups (10). For the pri-
mary prevention studies, the pooled relative risk for cardio-
vascular events with lipid-lowering therapy was 0.78 (CI,
0.67 to 0.89) and the pooled absolute risk reduction was
0.03 (CI, 0.01 to 0.04); the pooled estimate of the number
needed to treat to prevent an event was 34.5 for a weighted
trial average of 4.3 years. Of note, the results of ALLHAT-
LLT are included in the pooled estimates of relative risk
but not those of absolute risk reduction because the latter
data were not available.
For the secondary prevention studies, the pooled rela-
tive risk for cardiovascular events with lipid-lowering ther-
apy was very similar to that for primary prevention: 0.76
(CI, 0.59 to 0.93). However, because of the greater abso-
lute risk among patients with known coronary artery dis-
ease, the pooled absolute risk reduction was more than
twice as high (0.07 [CI, 0.03 to 0.12]) and the number
needed to treat for benefit was only 13.8 for a weighted
Clinical Guidelines Lipid Control in the Management of Type 2 Diabetes Mellitus
646 20 April 2004 Annals of Internal Medicine Volume 140 • Number 8 www.annals.org
trial average of 4.9 years. In trials of both primary and
secondary prevention, Vijan and colleagues conducted sen-
sitivity analyses excluding the trials that used gemfibrozil
(the Helsinki Heart Study for primary prevention and VA-
HIT for secondary prevention), but this did not change the
estimates of relative risk or absolute risk reduction (10).
SAFETY OF LIPID-LOWERING AGENTS
The current literature suggests that statins are ex-
tremely safe. Although rates of discontinuation and non-
adherence in clinical trials are approximately 15% or more
in many cases, rates of discontinuation typically are not
different from those of placebo. Rates of elevated levels of
liver or muscle enzymes did not differ between the statin
and placebo groups in recent large-scale studies. For exam-
ple, in the HPS, rates of elevated alanine aminotransferase
levels above twice the upper limit of normal were 1.8% in
the simvastatin group and 1.6% in the placebo group, and
rates of elevated creatine kinase levels were 0.3% in the
simvastatin group and 0.2% in the placebo group (15).
Neither of these differences was statistically significant.
Similarly, among the 5804 patients in PROSPER, only 1
person in each group had an alanine aminotransferase or
aspartate aminotransferase level more than 3 times the up-
per limit of normal (16). In addition, no patients had rhab-
domyolysis and 36 patients in the pravastatin group had
myalgia compared with 32 in the placebo group. Based on
the safety of these drugs, routine monitoring of liver or
muscle enzymes is probably not warranted except in pa-
tients with symptoms, patients who have liver enzyme ab-
normalities at baseline, or patients taking drugs that inter-
act with statins to increase the risk for adverse events.
SUMMARY
Given the markedly elevated risk for cardiovascular
events in most persons