- [Voiceover] So the 8th Joint National Committee,
or JNC-8, has recently proposed some useful guidelines
for when to treat patients with high blood pressure
and what blood pressure you should be shooting for.
So if you're over 60 years old, treatment should
be administered to try and lower your systolic
blood pressure to less than 150 millimeters of mercury,
and also lower a diastolic pressure to less
than 90 millimeters of mercury.
If you're less than 60 years old, though,
it's recommended to aim to get the blood pressure
to lower than 140 millimeters of mercury
on the systolic side, and again, less
than 90 millimeters of mercury on the diastolic side.
In addition, if you're above 18 years old
and have either a chronic kidney disease
or diabetes, it's also recommended to try
and get your blood pressure to lower
than 140 on the systolic side and lower
than 90 on the diastolic side.
To hit these targets, there are various treatment regimens
that might be recommended or prescribed,
and firstly and very importantly, lifestyle changes
might be suggested, and these will almost always
be used together with some sort of medication.
But one suggestion is to use something called DASH,
which stands for dietary approaches to stop hypertension.
As the name kind of suggests, this is a diet-based
lifestyle change, where we really emphasize eating foods
with less sodium as well as eating whole grains,
fruits, vegetables, and low fat dairy products.
Another lifestyle change, a huge, huge, huge one,
is to quit smoking and a bit on the same lines,
alcohol consumption should really
be done only in moderation.
Also, exercising 30 minutes most days of the week
and losing weight if already obese is generally suggested
as an important lifestyle change.
Now again, medications will also likely be prescribed
alongside these lifestyle changes.
And there are both first line and second line medications
for treating hypertension.
The first line medications are often recommended
as a first, or initial form of therapy
because studies have shown that they are the most effective
in preventing complications from hypertension,
and they're generally safe,
and in most cases, pretty inexpensive.
So since your blood pressure is related to the flow,
or the fluid volume in your body, right,
and the resistance in the vessels,
these medications will target one of these two factors.
And the first are thiazide diuretics.
Now these guys increase the excretion of sodium and water
by the kidneys, therefore they reduce your fluid volume
and so, your blood pressure.
You could also be prescribed calcium channel blockers,
and these block the channels in your vascular smooth muscles
that let calcium ions go through.
So, in effect, they reduce the contractions
of your blood vessels, and relax them.
And this essentially makes them larger
and reduces their resistance, which reduces
the blood pressure, right?
There's also ACE inhibitors, and these prevent
the renin-angiotensin-aldosterone system from taking effect.
So basically these inhibitors block the formation
of angiotensin II, which is a vasoconstrictor.
Since vasoconstrictors constrict your blood vessels,
this will end up widening the blood vessels
and basically reduce the resistance,
so it'll also reduce the blood pressure.
Not only that though, it'll prevent the formation
of aldosterone, which reduces sodium and water retention
and reduces blood volume,
and so blood pressure goes down as well.
And finally there's angiotensin II receptor blockers.
And basically these give the same result
as the ACE inhibitors but instead of blocking the formation
of angiotensin II, they block the receptors
that respond to angiotensin II.
But if the first line choices
for medications aren't effective,
then the physician might choose to go to the second line
choices for treating hypertension.
And some of those are as follows.
So first you could have the aldosterone receptor blockers
which do pretty much exactly what their name suggests.
They block the aldosterone receptors,
and since aldosterone causes sodium and water retention,
blocking these receptors will reduce your sodium
and water retention and therefore reduce your blood volume,
and so your blood pressure.
Now renin inhibitors inhibit this enzyme called renin,
which converts angiotensinogen to angiotensin I.
And this prevents the eventual formation
of angiotensin II and aldosterone,
which just like the ACE inhibitors reduces your resistance
and your blood volume.
Another one might be alpha-adrenergic blockers.
And these guys block the receptors that sit
on your vascular smooth muscles.
When these receptors are blocked, we inhibit
the vasoconstriction and therefore cause the vessels
to widen, which reduces your resistance.
Finally you've got your central adrenergic inhibitors.
And these work to prevent your brain
from sending sympathetic nervous system signals
that would normally cause your heart to beat faster
and your blood vessels to constrict.
So when we inhibit this response,
your blood vessels widen, your resistance goes down,
and the blood pressure goes down as well.