And what about secondary hypertension?
When do you see that?
I think a secondary hypertension,
it's rare.
It's only up to 10% of cases of hypertension.
It’s probably less than that.
But especially,
in a middle-aged adult,
when they come in with a very high blood pressure,
and particularly a blood pressure that’s not well controlled on initial therapy,
you can consider some differential diagnosis.
Thyroid disease is very easy to test for and pretty common,
but oftentimes it will also be associated with other symptoms
and a pulse if they're hyperthyroid that's high.
So, therefore, you can ferret out
that they have thyroid disease from other historical factors.
It’s rare when it’s just sitting there.
And the only symptom it's really causing is high blood pressure.
Hyperaldosteronism can be a problem.
Conn syndrome.
So, look for electrolyte abnormalities associated with that.
Renal artery stenosis is the most common cause of secondary hypertension.
And if it’s middle-aged adults,
you're probably talking about acquired renal artery stenosis
as opposed to congenital renal artery stenosis.
This – watch what their GFR, their glomerular filtration rate, is doing.
Watch their creatinine levels.
But it often needs
analysis with something like either a CT
or magnetic resonance angiography of the renal arteries.
And pheochromocytoma, we all worry about it.
It's actually incredibly rare.
And again, these patients usually have other symptoms – tremor,
sweating and weight loss – that can give away the
fact that they have this excess of catecholamines.
It's rare that it’s just – oh, the blood pressure is elevated by itself.
What do you to evaluate patients once they are diagnosed with hypertension?
Everybody gets a baseline electrocardiogram,
looking for things like left ventricular hypertrophy or prior cardiac damage,
glucose level or an HbA1c, something to screen for diabetes,
something to screen for hyperlipidemia,
a check of their electrolytes along with their kidney function,
as well as a hemoglobin level
and urinalysis or a microalbumin creatinine ratio
to check for the possibility of proteinuria and early kidney disease.
That's your baseline.
And these essentially should be repeated
at least when we talk about the electrolytes,
the urinalysis on an annual basis.
At least. At least on an annual basis.
Remember the lifestyle changes are still at the foundation
for the treatment of hypertension.
And actually if you look at something like the dietary approaches to stop hypertension,
that reduction on average with 11.5 over 5.5 points of mercury is really remarkable.
That's more powerful than most anti-hypertensive agents.
And, obviously, patients can do a DASH.
That’s going to yield other good things in terms of their cholesterol and their metabolism,
their body weight.
So, there are side benefits to that diet that are really wonderful.
But that reduction in blood pressure values is outstanding.
Weight loss certainly promotes a lower blood pressure as well.
So, that's one of the benefits of, say, bariatric surgery.
A lot of patients are cured of hypertension,
following the significant weight loss they experience with bariatric surgery.
But even following a good diet and exercise and losing 4 kilos
can result in a significant reduction in blood pressure.
And exercise, as I mentioned, in and of itself
can reduce blood pressure as well.
So, these are the keys.
And you can see that, if you put all of these things together,
many patients wouldn't – could avoid medical therapy
completely if they really embraced diet and exercise.
So, let’s return to our case. She has actually come back to clinic now.
And a repeat blood pressure, unfortunately,
despite trying to do her lifestyle changes in the past two weeks, is 150/94.
Her pulse is 86 bpm.
So, now, what do you want to do?
Do you want to allow six months for lifestyle changes to have an affect since she started them?
Do you want to start a thiazide diuretic,
start an alpha adrenergic blocker or start a beta blocker?
Which one would you choose?
I would go with a thiazide diuretic.
That is recommended as a first-line therapy by JNC 8.
So, here are the first-line treatments after lifestyle for hypertension.
And JNC 8 left this fairly open.
And again, these are only recommendations,
but the recommendations are broad and catch most patients, I think.
Thiazide diuretics are a great option for patients.
One thing, whenever I prescribe a diuretic,
is that I will ask them if they have any urinary issues.
Many older adults have overactive bladder or benign prostatic hypertrophy,
and therefore, already may be struggling with genitourinary issues.
I don't want to exacerbate that by giving them a thiazide diuretic.
I would choose something else for those patients.
The other thing is prescribing a thiazide alone – watch closely for the potassium because
thiazide promotes hypokalemia.
Whereas ACE inhibitors and ARBs, also considered a first-line agent,
can promote hyperkalemia.
So, therefore, a combination of one of those agents
with a thiazide is helpful in terms of maintaining normokalemia.
And calcium channel blockers have their own range of side effects,
but one thing they don't do much is affect electrolytes.
It’s also worth noting that atenolol is not recommended by JNC 8.
It doesn't confer overall the same mortality
benefit for cardiovascular disease
that these other agents maintain.