Heart Disease and Smoking
One of the more serious potential conditions from long-term
cigarette smoking is heart disease. That's a statement we hear
often in discussions of smoking. But what does it really mean?
What is heart disease, and how does smoking cause it?
In this context, the phrase 'heart disease' usually refers
to coronary artery disease. That's a condition in which a major
blood vessel that leaves the heart carrying oxygen-rich blood
becomes constricted. That increases the odds of a clot or
closure that causes a heart attack. That's why it's sometimes
called 'having a coronary'.
Long term, heavy smoking greatly increases the odds of that
happening for several reasons.
Carbon monoxide is present in cigarette smoke. It binds with
hemoglobin, the molecule in red blood cells that helps
transport oxygen throughout the body, including the heart.
Reducing the oxygen to the heart increases the odds of heart
disease.
Nicotine also reduces the amount of oxygen in the blood
while contributing to other conditions that are potentially
harmful. It increases blood clotting, which can have a direct
effect on the risk of heart attack, as described above.
Some effects that are produced by nicotine are even more
subtle yet still dangerous. One of the most serious long term
effects is that it encourages the growth of fatty deposits on
the arteries, constricting blood flow and hardening the blood
vessels.
One of the ways smoking carries out that damage is by
decreasing the amount of HDL (high density lipoprotein), the
'good' type of cholesterol. That encourages the growth of those
fatty deposits. That condition is called atherosclerosis and
it's a major heart attack risk factor.
Atherosclerosis effectively reduces the diameter of the
artery thereby increasing blood pressure. That makes it more
likely that any weakness present in the artery wall, something
termed an aneurysm, will lead to a rupture. That leads to
oxygen starvation to the brain, resulting in a stroke. That's
why one so often sees 'raises the risk of heart disease and
stroke' discussed in the same sentence.
Hardening an artery makes it also less able to withstand the
normal stresses and strains of its function.
Blood vessels carry blood and can only do so properly when
there are no holes or blockages. Any restriction or stoppage of
blood flow, however temporary, causes immediate health
problems. Tissues need a continual supply of blood or they die
very quickly.
There's also an overall effect from cigarette smoking that
contributes to the risk of heart disease. Smoking causes
several physical effects that reduce health. Reduced oxygen,
shortness of breath and other effects make exercise more
difficult and unpleasant. That, and lifestyle choices often
associated with smoking, reduce overall fitness.
The lack of exercise and the increased weight gain that can
accompany it increases the risk of heart disease and heart
attack. The body is less able to withstand strains that might
otherwise be minor. It is less able to withstand the serious
biological shock that occurs when a heart attack finally
happens. That increases the odds that a heart attack will be
fatal.
Long-term, one-pack-a-day smokers have 2-4 times the chance
of developing coronary heart disease than do non-smokers.
Quitting today improves your odds immediately. Within 3 months
circulation improves. After a year, the odds are half that of a
smoker. After 5-15 years, the odds are that of someone who has
never smoked. Don't think it's too late. Start today on a
program to quit smoking.
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