Medications: The third step in preventing coronary heart
disease
The first two steps we can take to prevent heart disease are
some tests and a few lifestyle changes, which was discussed elsewhere. For many
people, taking certain medications under a doctor's supervision to prevent
heart disease is necessary and very beneficial. It can be called the third step
to prevent heart attack.
The two main groups of drugs used to prevent heart disease
are 1. Cholesterol lowering drugs like statins and 2. “blood
thinners” like aspirin.
For people who are known to have coronary heart disease,
for example people having angina or who have had heart attack, angioplasty or bypass surgery, or brain stroke or disease
in the arteries of the legs, both the above kinds of medicines are important and
advisable for lifelong use under medical supervision. This is so that the
chances of progression of disease or recurrence of untoward events like heart
attack are minimized.
Those who have no symptoms of the disease but have a high
coronary artery calcium score (done due to any reason) or if the heart arteries
appear diseased in CT coronary angiography (again, done for any reason), it is
better to take these two drugs as per the doctor's advice.
Statins not only lower LDL cholesterol in the blood but also
stabilize or ‘shrink’ the fatty deposit in the arteries, preventing their
erosion or rupture which can lead to a heart attack.
Other drugs which may be advised in addition to or instead
of statins are ezetimibe, bempedoic acid, PCSK9 inhibitors, fibrates and ecosapent
ethyl, which reduce cholesterol and triglycerides.
Drugs like low dose aspirin prevent clumping of platelets
and clotting which can occlude arteries leading to a heart attack. Other “blood
thinners” which may be advised in addition to or instead of aspirin are clopidogrel,
ticagrelor and prasugrel.
What about people who have not had any sign of heart
disease and are apparently healthy? Should they be taking these preventive drugs?
Well, statins may also be necessary for those who have no
symptoms of heart disease, but who are at high risk of developing heart disease
in the future.
So how do you know in seemingly healthy people who are more
likely to develop heart disease in the future?
The likelihood of future heart disease in apparently healthy
people depends on their risk factors and certain physical conditions. Doctors
take these two factors into consideration or use certain formulas (risk scores)
to predict how likely people are to have a heart attack in the next 10 years.
All risk scores (Google ‘CVD risk stratification in Indians’) are estimated on
the basis of how many and how severe the risk factors are in us. As mentioned
earlier the known factors are hypertension, diabetes, cholesterol, smoking,
obesity, lifestyle, improper diet, family history of heart disease etc.
If the chance is more than 20% according to the risk scores,
or if if LDL cholesterol is over 190 mg% or if there is long standing diabetes,
then taking a statin (of course, in addition to healthy lifestyle choices) may
have more benefits than risks.
If the likelihood of having heart disease on the basis of risk
scores is less than 5%, then only lifestyle changes may suffice to prevent the
disease.
If the chance is between 5% and 20%, the decision to take
the drug requires further tests, such as coronary artery calcium score, doppler
test of femoral and carotid arteries, BP difference between all 4 limbs and blood
tests like apoB, hs CRP, LPA, troponin, etc. Other physical conditions like lung
or joint disease, kidney disease, HIV, high blood pressure, diabetes during pregnancy
in women or a history of premature birth or lack of breast feeding may put one
at higher risk so that it may be beneficial in these people also to take a
statin under medical guidance.
The decision to start a statin should be based on discussion
with the doctor and after understanding its benefits versus harm for the
individual.
Other ‘preventive’ drugs are all medications to keep blood
pressure and sugar under control. Of particular preventive benefits are certain
medications such as SGLT2 inhibitors and GLP1 agonists for diabetes, RAAS
blockers for hypertension, beta blockers for hypertension with angina, or after
a heart attack or heart failure.
Should seemingly healthy people take aspirin for life to
prevent heart attacks?
It was a popular belief that everyone should take baby
aspirin to prevent heart attacks because heart attacks are caused by blood
clots in addition to fatty deposits and aspirin prevents these clots from
forming. But after a few years of research on many people, it was found that
along with the benefits of aspirin, there is also adverse effect of bleeding.
In people who have a history of bleeding or are over 70 years of age, the risk
of bleeding outweighs the benefits of preventing heart attacks, so the net harm
is greater. So, taking aspirin over the counter or without medical advice is
inappropriate for such people. Yes, it can be taken to prevent heart attacks
(not to prevent death) in people younger than 70 with risk factors for heart
disease or with long-standing diabetes, but after consulting a cardiologist.
Thus, almost 90% of heart attacks can be avoided by 3 steps:
1. certain tests, 2. certain lifestyle changes and 3. taking certain
medications as advised by the doctor. Despite all these efforts, if a heart
attack (the remaining 10%) still occurs, the damage caused by the heart attack
can be avoided by immediately recognizing the symptoms and getting prompt
treatment.