Guidelines. Risk assessment and lipid modification for primary and secondary prevention of cardiovascular disease: Summary of NICE guidance

Full text

GUIDELINES
Risk assessment and lipid modification for primary
and secondary prevention of cardiovascular disease:
summary of NICE guidance
Angela Cooper, Norma O’Flynn, on behalf of the Guideline Development Group
Why read this summary?
Cardiovascular disease remains a leading cause of
morbidity and mortality in the United Kingdom.
Randomised controlled trials have shown benefit
from modifying risk factors in people at risk of
developing cardiovascular disease and in those who
have evidence of established disease. Currently
patients are often assess ed opportunistically and
treated on the basis of individual clinical or laboratory
results rather than on their overall level of risk of
developing cardiovascular disease. This article sum-
marises the most recent recommendations from the
National Institute for Health and Clinical Excellence
(NICE) on the effective identification and assessment
of people at risk of cardiovascular disease, and on the
modification of lipids in primary and secondary
prevention. The detailed consideration of the evidence
is available in the full guideline (www.nice.org.uk/
CG67).
1
Recommendations
NICE recommendations are based on systematic
reviews of best available evidence. When minimal
evidence is available, recommendations are based on
the guideline development group’s opinion of what
constitutes good practice. Evidence levels for the
recommendations are in the longer version of this
article on bmj.com.
Identifying th ose at risk of cardiovascular disea se for
primary prevention

Use a systematic strategy rather than opportunistic
assessment to identify people at high risk of the
disease.

Exclude patients known to have established cardio-
vascular disease or who are already considered at
high risk, such as patients with diabetes or lipid
disorders.

Estimate risk of cardiovascular disease using risk
factors already recorded in primary care records,
such as age, sex, and blood pressure.

Use the estimated risk value to prioritise patients, and
arrange a full formal risk assessment for patients
whose estimated 10 year risk is ≥20%.

Assess risk (both estimate and formally) using the
1991 Framingham 10 year risk equations, with the
following variables: age (30-74 years), sex, systolic
blood pressure (mean of previous two systolic
readings), total cholesterol concentration, high den-
sity lipoprotein cholesterol concentration, smoking
status, and presence of left ventricular hypertrophy.
2

Fasting lipid levels are not needed for risk assessment.

Record factors important for development of cardio-
vascular disease, such as ethnicity, body mass index
(kg/m
2
), and family history of premature heart
disease.

Adjust the risk score for factors im portant for
development of cardiovascular disease but not
included in the risk score as follows:
- If there is one first degree relative with premature
coronary heart disease, increase the estimate by 1.5;
if there is more than one first degree relative with
premature coronary heart disease, increase the
estimate by up to 2
- Increase the estimated risk for men with a South
Asian background by 1.4.

Use clinical judgment to decide on treatment if the
risk score is near the threshold for treatment and
evidence exists of other factors that may predispose a
person to premature cardiovascular disease, such as
socioeconomic status, severe obesity (body mass
index greater than 40), or the patient is already taking
antihypertensive medication or has recently stopped
smoking.

Consider further investigations and specialist review
in people in whom familial hypercholesterolaemia or
other monogenic lipid disorders are suspected
because of clinical findings, lipid profiles, and family
history of premature coronary heart disease.

When using risk estimation tools for identifying risk
of cardiovascular disease, note that these tools:
- Can give only an approximate risk value, and
interpretation of risk scores should always reflect
informed clinical judgment
- Do not include people aged 75 years or older, but
people 75 years and over may benefit from statin
treatment, particularly if they smoke or have high
blood pressure.
Communicating c ardiovascula r risk with the patient

Explain the process of risk as sessment and the
meaning of risk in everyday, jargon-free language.

Provide information on absolute risk rather than
relative risk, and use graphical and textual formats to
inform patients on risks and benefits of interventions.
This is one of a series of BMJ
summaries of new guidelines,
which are based on the best
available evidence; they will
highlight important
recommendations for clinical
practice, especially where
uncertainty or controversy exists.
Further information about the
guidance, a list of members of the
guideline development group, and
the supporting evidence
statements are in the full version
on bmj.com.
National Collaborating Cent re for
Primary Care, Royal College of
General Practitioners,
London SW7 1PU
Correspondence to: N O
’
Flynn
noflynn@rcgp.org.uk
BMJ 2008;336:1246-8
doi:10.1136/bmj.39554.624086.AD
PRACTICE
1246 BMJ | 31 MAY 2008 | VOLUME 336


Explore prior information given and patients’
personal beliefs on health and their readiness to
make lifestyle changes and develop a shared manage-
ment plan.
Lifestyle advice
All patients at high risk of cardiovascular disease
should be advised to:

Eat a diet low in saturated fat and dietary cholesterol
and replace saturated fats by monounsaturated and
polyunsaturated fats

Eat at least five portions of fruit and vegetables a day
and at least two portions of oily fish a week

Take 30 minutes of physical activity a day, of at least
moderate intensity, at least five days a week; activities
should include those that can be incorporated into
everyday life, such as walking, using stairs, and
cycling

Quit smoking

Limit alcohol consumption (for men to up to 3-4 units
a day, for women up to 2-3 units a day).
The use of plant sterols and stanols is not to be routinely
recommended for patients at high risk.
Drug treatment for lipid modification in primary and
secondary prevention

Measure fasting total, low density lipoprotein and
high density lipoprotein cholesterol concentrations,
and triglyceride concentrations once before starting
drug treatment (if fasting concentrations are not
already available) except in pat ients wit h acute
coronary syndrome, where fasting concentrations
should notbemeasureduntilthreemonthsafter acute
coronary syndrome.

When the decision has been made to start statin
treatment, prescribe a drug shown to be of clinical
benefit and with a low acquisition cost (taking into
account the required daily dose and the product price
per dose).
3

When starting or increasing statin treatment, discuss
with the patient the risks andbenefits of treatment and
take into account comorbidities, multiple medica-
tions, life expectancy, and the patient’s own prefer-
ences.
Statins for primary prevention

Consider all other modifiable risk factors for cardio-
vascular disease , comorbidities, and secondary
causes of dyslipidaemia, and optimise their manage-
ment if possible. Consider therefore smoking status,
alcohol consumption, blood pressure,
4
body mass
index or other measure of obesity,
5
fasting blood
glucose concentrations, renal function, liver function
(transaminases), and thyroid stimulating hormone
concentrations (if dyslipidaemia is present).

Offer statin treatment as part of primary prevention
for adults with a 10 year risk of ≥20%.
3

Treat with simvastatin 40 mg. If this is contra-
indicated or drug interactions are possible, choose a
lower dose or an alternative such as pravastatin.

Do not routinely offer higher intensity statins
—
that
is, statins used in doses producing greater cholesterol
lowering than simvastatin 40 mg ( for example,
simvastatin 80 mg).

Do not set a target concentration for total or low
density lipoprotein cholesterol in primary preven-
tion.

Once a patient has started taking a statin, repeat lipid
measurement is unnecessary. Clinical judgment and
the patient’s preference should guide the review of
drug treatment and whether to review the lipid
profile.
Statins for secondary prevention

Consider all modifiable risk factors, comorbidities,
and secondary causes of hyperlipidaemia, and
optimise their management. Do not delay treatment
until optimisation of risk factors has been achieved.

Offer statin treatment to adults with clinical evidence
of cardiovascular disease.
3
Start treatment with
simvastatin 40 mg. If there are potential drug
interactions, or simvastatin 40 mg is contraindicated,
choose a lower dose or an alternative preparation
such as pravastatin.

Offer people with acute coronary syndrome a higher
intensity statin.

Consider increasing the dose to simvastatin 80 mg or
a drug of similar efficacy and acquisition cost if a total
cholesterol concentration of <4 mmol/l or a low
density lipoprotein cholesterol concentration of
<2 mmol/l is not attained.

Use an “audit” concentration of total cholesterol of
5 mmol/l to assess progress in populations being
treated for secondary prevention, as more than half
will not achieve a total cholesterol concentration of
<4 mmol/l or a low density lipoprotein cholesterol
concentration of <2 mmol/l.
Monitoring sta tin treatment

If a person taking a statin starts taking additional
drugs or needs treatment for a concomitant illness
that interferes with metabolic pathways or increases
the propensity for drug and food interactions,
consider reducing the statin dose or temporarily or
permanently stopping it.

Advise people taking statins to seek medical advice if
they develop muscle symptoms (pain, tenderness, or
weakness); if this occurs, measure creatine kinase
concentrations.

Do not routinely monitor creatine kinase in those
who are asymptomatic.

Measure baseline liver enzyme (transaminases) levels
before statins are started, within three months of
treatment starting, and at 12 months, but not again
unless clinically indicated. People whose levels are
raised but are less than three times the upper limit of
normal should not be routinely excluded from statin
treatment.

If a person develops an unexplained peripheral
neuropathy, discontinue statins and seek specialist
advice.
PRACTICE
BMJ | 31 MAY 2008 | VOLUME 336 1247

Other lipid lowering agents

Do not routinely offer fibrates or anion exchange
resins for primary or secondary prevention, but
consider either of these options if statins are not
tolerated.

Do not offer nicotinic acid for primary prevention,
but consider it for secondary prevention in people
who cannot tolerate statins.

Do not offer an anion exchange resin, fibrate, or
nicotinic acid combined with a statin for primary
prevention.

Consider people with primary hypercholesterolae-
mia for ezetimibe treatment (see the NICE technol-
ogy appraisal on ezetimibe
6
).
Overcoming barriers
Effectively implementing the recommendations for
primary prevention depends on a structured, systema-
tic approach to identifying people at high risk of
cardiovascular disease. Formal risk assessment will
require good communication with patients and educa-
tion on the meaning of the risk and the benefits and
risks of treatment. Standard models of care should
include advice and support in lifestyle changes for both
primary and secondary prevention. The costing tool
being developed by NICE can be used to estimate
additional costs (www.nice.org.uk/CG67).
Contributors: Both authors contrib uted equally t o dra fting and revising the
summary. NO
’
F is the guarantor.
Funding: The National Collaborating Centre for Primary Care was
commissioned and funded by th e Nationa l Inst itute for Health and Clinical
Excellence to write this summary.
Competi ng interests: None declared.
Provenance and peer review: Commissioned; not externally peer
reviewed.
1 National Institute for Health and Clinical Excellence. Lipid
modification: cardiovascular risk assessment and the modification of
blood lipids for the primary and secondary prevention of
cardiovascular disease. London:NICE,2008. www.nice.org.uk/ CG67
2 Anderson KM. Cardiovascular disease risk profiles. Am Heart J
1991;121:293-8.
3 National Institute for Health and Clinical Excellence. Statins for the
prevention of cardiovascular events in patients at increased risk of
developing cardiovascular disease and those with established
cardiovascular disease. London: NICE,
2006. www.nice.org.uk/TA094
4 National Institute for Health and Clinical Excellence. Hypertension:
management of hypertension in adults in primary care. London: NICE,
2006. www.nice.org.uk/CG34
5 National Institute for Health and Clinical Excellence. Obesity
—
the
prevention, identification, assessment and management of
overweight and obesity in adults and treatment. London: NICE,
2006. www.nice.org.uk/CG43
6 National Institute for Health and Clinical Excellence. Ezetimibe for the
treatment of primary (heterozygous familial and non-familial)
hypercholesterolaemia. London: NICE,
2007. www.nice.org.uk/TA132
Commentary: Controver sies in NICE guidance on lipid
modification for the prevention of cardiovascular disease
Francesco P Cappuc cio
The new guidelines from the National Institute for
Health and Clinical Excelle nce (NICE) on lipid
modification for the prevention of cardiovascular
disease will guide the way we assess cardiovascular
risk and treat lipids, both in primary and in secondary
care. What are the new aspects, and what is it that might
spark controversy in this new publication?
Risk assessment
To identify those requiring primary prevention of
cardiovascular disease, the guideline reaffirms the
threshold of a 10 year cardiovascular disease risk
>20% in people aged over 40 years. Its recommenda-
tion of a systematic, rather than opportunistic, risk
assessment is welcome, particularly in primary care.
The new guidelines wisely reaffirm the 1991 Framing-
ham risk score as the score of choice for guiding
primary prevention.
However, they also retain subjective, non evidence-
based adjustments. They advise increasing the risk
estimate by 1.5-2.0 in the presence of premature family
history and by 1.4 in South Asian men, and suggest
clinical judgment for socioeconomic status and severe
obesity. This is a missed opportunity for tackling at
least some of these matters, such as the ethnic variations
in vascular risk, with an evidence based approach.
The Framingham risk does not perform well in ethnic
groups in the United Kingdom,
1
andintheabsenceof
UK cohort studies with significant proportions of black
and ethnic minority groups, a web based tool
(ETHRISK) has been developed for primary care
physicians to allow for such variation.
2
This pragmatic
tool is based on a recalibration of existing Framingham
risk scores against survey data on ethnic group risk
factors and disease prevalence compared with the
general population to produce 10 year risk in seven
British black and ethnic minority groups. This could
have been incorporated into most primary care compu-
ter systems. Although the tool is not ideal, its use in
clinical practice would have at least partially prevented
inequalities in cardiovascular disease prevention that are
not easily overcome by subjective judgment.
Lifestyle advice
The approach to lifestyle advice is disappointing. It
perpetuates the belief that, as each listed measure has
been proved to reduce cardiovascular risk, providing
such collective advice will be effective. This is not the
case.
3
Maybe a more tailored, patient centred approach
Cli nical Sciences Research
Institute, University of Warwick
Medical School,
Coventry CV2 2DX
f.p.cappuccio@warwick.ac.uk
BMJ 2008;336:1248-9
doi:10.1136/bmj.39554.624086.AD
PRACTICE
1248 BMJ | 31 MAY 2008 | VOLUME 336