You take your blood pressure medicine faithfully. You eat less salt, exercise more and try to lower your stress. Yet every time you check, your blood pressure is still high. It won’t budge.
That can be upsetting and even frightening. You might wonder if there's something else happening.
Sometimes, high blood pressure (hypertension) that does not get better with medications may be caused by another health problem. One less common reason is a small noncancerous tumor called an aldosteronoma. This tumor can change how your body controls blood pressure.
If you have high blood pressure that won’t go away, you’re not alone. Many people have this problem for years before they find out what’s wrong. Keep reading to learn more about what aldosteronoma is and how it can be treated.
What exactly is an aldosteronoma?
You have two small adrenal glands, one on top of each kidney. They make important hormones that control your metabolism, how your body responds to stress and your blood pressure.
An aldosteronoma is usually a noncancerous tumor that appears on one of your glands. It makes the gland produce too much of a substance called aldosterone.
“Aldosterone is one of the hormones that primarily works on the kidneys to help regulate blood pressure by adjusting electrolytes and blood volume,” said Panagiotis Bletsis, MD, an endocrine surgeon with Banner Health. “It helps your kidneys manage salt, water and potassium levels in your blood.”
When the hormone is overproduced, your body holds onto extra salt and water but loses potassium. This can make your blood pressure stay high, even if you take medicines.
When blood pressure won’t respond
If you’re on three or more blood pressure medications and your readings are still high, you may have what’s called treatment-resistant hypertension. In these cases, an aldosteronoma or another form of primary hyperaldosteronism could be the cause.
“Most medicines lower blood pressure in different ways but they don't fix the main hormonal problem caused by aldosteronoma,” Dr. Bletsis said. “This means high blood pressure can stay high even if you're taking multiple medications. Over time, high blood pressure can damage your heart, kidneys and blood vessels.”
Research shows that up to 25% of people with hard-to-treat high blood pressure might have a condition called primary hyperaldosteronism.
Symptoms you might notice or not notice at all
“Many people with an aldosteronoma may not experience any obvious symptoms,” Dr. Bletsis said. “Symptoms someone might notice are related to very high blood pressure or low potassium.”
High blood pressure symptoms might include:
- Headaches
- Blurred vision
- Chest pressure
- Shortness of breath
- Nausea
- Confusion
Low potassium levels symptoms might include:
- Fatigue
- Muscle weakness
- Numbness or tingling
- Frequent urination (peeing)
- Heart rhythm changes
[Also read: Why Potassium Is Important for Your Health.]
Even if you feel fine, chronic high blood pressure is a serious warning sign, especially if you are younger than 50.
“Anyone with high blood pressure that’s hard to control, especially if you are younger than 50 years old, should be checked,” Dr. Bletsis said. “This is particularly important if you also have low potassium that needs supplements or medications like spironolactone or eplerenone.”
How it’s diagnosed
The first step is bloodwork to check your potassium, aldosterone and renin levels (an enzyme in the kidneys that helps regulate blood pressure).
“Primary hyperaldosteronism is diagnosed with blood tests where potassium is usually low or low-normal, aldosterone is high and renin is low,” Dr. Bletsis said.
If the blood tests suggest an aldosteronoma, imaging such as a CT scan or an MRI may help locate adrenal nodules. But sometimes, these tumors are too small to be seen on scans.
“Aldosteronoma may be very small and not seen on imaging,” Dr. Bletsis said. If the diagnosis is clear on blood tests, it doesn’t matter whether imaging shows a nodule or not. The next step is an outpatient radiology procedure called adrenal vein sampling.”
This procedure takes a blood sample from both adrenal gland veins to test aldosterone levels.
Treatment and recovery
If testing shows that only one adrenal gland is overproducing aldosterone, surgery can often fix the problem.
“As long as one side is three times greater than the other, then surgery to remove that adrenal gland is very effective in treating primary hyperaldosteronism,” Dr. Bletsis said.
Surgery is typically minimally invasive and highly successful.
“If someone has had high blood pressure for less than 10 years, there is more than a 50% chance they can be completely cured. If they have had it for more than 10 years, the chance of being completely cured is lower,” Dr. Bletsis said. “However, about 90% of patients will still see big improvements. These improvements include needing fewer medicines, better control of blood pressure and normal potassium levels.”
If both adrenal glands are affected, surgery isn’t recommended. Instead, medications like spironolactone or eplerenone can help block aldosterone’s effects.
“This doesn’t cure excess hormone production but it does improve blood pressure and potassium levels in most cases,” Dr. Bletsis said.
Why early diagnosis matters
When an aldosteronoma goes undiagnosed, it can quietly harm your body for years.
“Over time, worsening and more difficult-to-control high blood pressure will have negative impacts on the heart, blood vessels and kidneys,” Dr. Bletsis said. “That can cause heart attack, heart failure, stroke or kidney failure.”
When to talk to your doctor
Talk to your health care provider about being tested for an aldosteronoma if:
- You’re on three or more blood pressure medications and your readings are still high
- You’ve had low potassium or need supplements
- You were diagnosed with high blood pressure before age 50
- You have adrenal nodules found on imaging
- You have a family history of early heart disease or stroke
What you can do right now
While your care team investigates the cause, you can take steps to protect your health:
- Keep a daily blood pressure log and share it with your provider
- Take medications as prescribed, even when results seem low
- Limit salt; even small changes can make a difference
- Stay active and manage stress to support overall heart health
- Ask questions if you have concerns
The bottom line
If your blood pressure refuses to respond, it’s not your fault. But it’s not something to ignore. Sometimes the real issue lies in your hormones, not your habits.
An aldosteronoma may be small but its effects on your health can be big. With testing and treatment, you can help restore balance and give more control over your health.
Talk to your provider or a Banner Health specialist about your high blood pressure. You may find the root cause that has been hiding in plain sight.
