Advanced Institute for Diabetes & Endocrinology

Endocrine Hypertension

Endocrine Hypertension (Blood Pressure)

There are many causes of high blood pressure, but one that is being appreciated in recent years is that caused by hormone secretions.

  • Excess adrenaline (pheochromocytoma)
  • Excess thyroid hormone (thyrotoxicosis)
  • Excess aldosterone
  • Excess cortisol (Cushing syndrome)

The most common cause of endocrine mediated hypertension is excess aldosterone, which is made in the adrenal gland.

  • Because it is so common, we recommend patients be screened if they have any of the following:
    • Blood pressure > 140/90
    • Take 3 or more blood pressure medications but still have blood pressure > 140/90
    • Require 4 medications to control blood pressure OR
    • High blood pressure AND low potassium OR
    • High blood pressure AND an adrenal nodule OR
    • High blood pressure AND sleep apnea OR
    • Family members with early onset high blood pressure or early stroke
    • A parent or sibling with excess aldosterone

The adrenal glands are like “top hats” on the kidneys, their job is to produce different kinds of steroid hormones, especially cortisol & adrenaline.

  • These hormones are necessary for life because they regulate stress responses that control blood pressure and how our cells use glucose.
  • But the glands also make other kinds of hormones like aldosterone, which regulates certain electrolytes, or sex hormones.

Because we do so many CAT scans for other reasons, we often find nodules in glands “by accident” and these are called incidentalomas.

  • If we find one of these nodules, we always check it for aldosterone.

Sometimes patients take blood pressure medications that interfere with the tests for aldosterone, so we want to switch or stop those medications for 4-6 weeks before testing.

What tests will check for aldosterone?

  • First we make sure you have potassium supplements if you need them. After potassium is normal we start phase 1 testing.
  • An 8 am blood test for aldosterone and renin. We use the ratio of the two to determine the need for additional testing.

How do the confirmatory tests work?

  • If the ratio of aldosterone-to-renin is at least 20, especially if the aldosterone level is > 15, we start phase 2 of testing.
  • The patient needs to eat about 6000mg sodium every day for 3 days.
    • The easiest way to do this is to add 3 cans of soup to your diet every day for 3 days. There are salt tablets, but they can be expensive and make people feel sick.
    • On the start of the 3rd day, continue the high sodium diet & collect urine for 24 hrs. We will check this for both sodium and aldosterone. If the sodium is > 200 and the aldosterone is > 12 mcg we diagnose primary hyperaldosteronism.

Only if the labs are positive for aldosterone will we check a CAT scan of the adrenal glands.

  • If a nodule is detected, we will refer to a specialized facility to check the adrenal veins, which will tell us if that nodule is actually making the aldosterone.
    • If the nodule IS making aldosterone, the best treatment is to take it out.
    • Most people who have their aldosterone-secreting nodule removed can come off of their blood pressure medications after the surgery.
  • If NO nodule is found, the excess aldosterone can be treated with a medication, either spironolactone or eplerenone.

What if my CAT scan shows nodules on BOTH sides?

Usually the safest way to treat this is with the spironolactone or eplerenone, and outcomes are very good long-term.

What if my CAT scan showed NO nodules, but the glands look bigger than expected?

We call this hyperplasia. Sometimes this means there’s a tiny nodule in there, but other times it just means the adrenal glands have more cells than usual. The treatment is the same: spironolactone or eplerenone.

Resources

  • Columbia Adrenal Center: http://columbiasurgery.org/conditions-and-treatments/primary-hyperaldosteronism-conns-syndrome
  • Endocrine Surgeons: http://endocrinediseases.org/adrenal/hyperaldosteronism.shtml
  • Mayo Clinic: www.mayoclinic.org
    • Benign adrenal tumors
    • Primary aldosteronism