Primary hypertension | Circulatory System and Disease | NCLEX-RN | Khan Academy

Primary hypertension | Circulatory System and Disease | NCLEX-RN | Khan Academy


– [Voiceover] All right. So, the most common type
of hypertension is called primary hypertension. This accounts for about
90 to 95% of all cases. And there’s a less common type
that accounts for the rest, and that’s called secondary hypertension, that we’ll get into a little
more in-depth in a later video. But, for now, let’s just focus
on this primary hypertension. So, what is it? Well, we call it primary
hypertension when there’s actually no known cause, usually
because it develops gradually over a long period of time. It seem a little weird, though, right, that for such a high percentage,
we don’t know exactly what caused this high blood
volume or high resistance in the blood vessels that
leads to a high blood pressure. But one thing we do look
for, though, that helps us get an idea of how it
might have cropped up, are called risk factors, which
are basically like conditions or habits that make
someone much more likely to develop a certain
disease, like hypertension. Since primary hypertension
typically develops gradually over time, increasing age
actually, in itself, is considered a risk factor. High blood pressure becomes more common after age 45 in men and age 65 in women. A second, little more
tangible risk factor, one that shouldn’t come
to much of a surprise, is smoking or even chewing tobacco. Not only do these immediately
raise your blood pressure temporarily, but the
chemicals found in tobacco can actually damage the
lining of your artery walls or your plumbing system,
right, which increases the resistance in your vessels
and therefore increases your blood pressure. Not only that, second-hand
smoke can also have the same effect of increasing
your blood pressure. Smoking, therefore, is not good
for your blood pressure or, really, anything else for that matter. Another risk factor, sort
of along the same lines, is drinking too much alcohol. Having more than three
drinks in a single sitting can, just like smoking, temporarily raise your blood pressure. And repeated binge-drinking
over time can also damage your heart, making that heart a less-efficient pump. And if it’s not pumping as
efficiently, your body tries to increase the pressure
in your blood vessels to sort of compensate. With that said, drinking
alcohol should be done only in moderation, which,
in general, is considered no more than two drinks
per day for men under 65 and no more than one drink per day for men over 65 and women of all ages. But let’s remember to
keep in mind that alcohol contains calories that may
contribute to weight gain, right, which kind of segues us into
the next major risk factor, which is obesity. The more you weigh, the more
blood you need to supply your body with oxygen and nutrients. If you remember, trying to
jam more blood into the pipe, so your blood vessels, tends
to increase what we call the flow, which in turn
increases the pressure on your artery walls, and
therefore, your blood pressure. And so, another one that
sort of plays off of obesity and even can contribute
to obesity is not being physically active. Physical activity helps train your heart to be more efficient and get stronger. Without it, your body tries to compensate for a weaker heart and weaker circulation, just like the heavy alcohol consumption, by increasing the pressure
in your blood vessels. Another risk factor is
poor diet, specifically one that’s very high in sodium or salt, because we know that fluid
tends to follow salt, right? So, if there’s more salt
in your body, your body’s going to retain more fluid,
which is going to, in turn, increase your blood pressure. Now, most of the risk factors
that I’ve mentioned so far seem like pretty controllable
risk factors, right? One that tends to
contribute to hypertension and is a little more out of your control is actually genetics. Just like hair and eye color
can sort of run in your family, so too can hypertension. So, if your mother or your
father has hypertension, you or your siblings have a
higher risk for hypertension. So, that means it’s all
the more important to keep all these risk factors in check, right? Another genetic factor, one
that might be a little more surprising, is that those
of African American heritage tend to have what’s
called salt sensitivity, meaning that they retain
more sodium and water, meaning that, again, it’s
more important to keep risk factors like diet and
salt consumption in mind. So, these are all sort of lumped
into primary hypertension, right, where there’s no
known identifiable cause. If there is an identifiable cause, it’s called secondary hypertension. For example, if someone has
an underlying kidney disease which causes them to hold on to more water and raises your blood
pressure, we would call that secondary hypertension,
because we know exactly why it’s raising the blood pressure. But, again, let’s talk
about that a little more in a later video. For now, let’s quick-talk
about the signs and symptoms of hypertension. What’s crazy about this,
though, is that most often, there aren’t any. Many patients don’t even
know they have hypertension. Since there usually aren’t
any signs or symptoms, you might hear it referred
to as a “silent disease” or sometimes even a “silent killer.” So, that’s why when you go in
for your annual physical exam, a blood pressure
measurement is so important and is always included. If your blood pressure is
extremely high in rare cases, then symptoms may appear and can include things like headache,
blurred vision, dizziness, and disorientation.