stroke by 19-32% in patients with or without evidence of CHD.
Treatment benefits with statins appear similar in men and women, and are
independent of age up to 75 years, but data are lacking for patients above this
age.
Statins provide useful preventative benefit for patients with
clinically obvious antherosclerotic disease, such as CHD, and for those without
such features but with an absolute risk of 15% or more over 10 years.
However, treating all those with a risk of 15% or more over
10 years would in effect include around 25% of UK adults and is not achievable
with current NHS funding. A more realistic approach, therefore, is to ensure
that all those with an absolute risk above 30% over 10 years receive optimum
statin therapy, with appropriate monitoring of lipid concentrations and advice
on non-drug measures, and extending statin therapy to remaining individuals with
a risk level of at least 15% over 10 years, as resources permit.
These objectives involve identifying all patients with
clinically obvious atherosclerotic disease, who do not need formal assessment of
absolute coronary risk before starting secondary prevention interventions. It
also involves identifying people without such clinical features, but who
nonetheless are likely to be at increased CHD risk, such as those with a family
history of premature CHD, clinical signs of hyperlipidaemia, or hypertension, or
who smoke. These individuals require formal assessment of absolute risk.
Special consideration needs to be given to certain groups.
These include: patients with diabetes mellitus, those of South Asian descent and
patients with familial hypercholesterolaemia.
Patients with clinically overt atherosclerotic disease should
be started on a statin. In patients without clinically overt atherosclerotic
disease, but with an estimated CHD risk of about 30% over 10 years, statins
should be used to lower serum total cholesterol concentrations to below 5mmol/L or
by 20-25% (or LDL-cholesterol concentrations to below 3mmol/L or by 30%),
whichever results in the lower concentration.
Whether or not treatment with a statin is indicated,
appropriate lifestyle modifications should be identified and continued
indefinitely in all patients worthy of risk assessment. In primary prevention,
smoking cessation alone may reduce absolute CHD risk sufficiently to eliminate
the need for statin treatment.
The most accurate way of estimating absolute CHD risk and,
therefore, potential benefits from primary prevention interventions, is by
weighting and collating the influence of all major risk factors, using a risk
function derived from epidemiological data.
Several methods have been developed for assessing risk in the
UK population, and are generally available as printed charts or computer
programmes
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