Primary Aldosteronism (Hyperaldosteronism)

Primary aldosteronism (hyperaldosteronism) is a condition that occurs when the adrenal glands produce too much aldosterone, the hormone responsible for balancing potassium and sodium in the body.

Overproduction of aldosterone causes the body to retain more sodium and lose potassium, which leads to elevated blood pressure. Patients with this condition are at increased risk of heart disease and stroke.

Symptoms

The main symptom experienced by patients with primary aldosteronism is moderate to severe high blood pressure, which is often resistant to drug treatments and accompanied by low potassium levels.

Other symptoms include:

  • Fatigue
  • Headaches
  • Muscle weakness
  • Numbness
  • Sporadic temporary paralysis

Causes and Risk Factors

Many cases of primary aldosteronism are caused by a benign tumor in an adrenal gland; some are caused by overactivity of both adrenal glands, a condition known as bilateral adrenal hyperplasia.

In rare cases, the condition may be caused by cancerous tumors in the outer layer of an adrenal gland, or by a genetic condition known as glucocorticoid-remediable aldosteronism.

The condition is most common in people between the ages of 30 and 50.

Diagnosis

When diagnosing primary aldosteronism, the physician often will first order a blood test to determine the patient’s aldosterone and renin levels. Renin is an enzyme released by the kidneys that helps regulate blood pressure. If elevated amounts of aldosterone and minimal amounts of renin are found, this could be a sign of primary aldosteronism, and other tests may be ordered to confirm the diagnosis.

These tests may include salt loading, which involves the intake of high levels of sodium followed by blood and urine testing to determine how the body is handling the salt and responding with aldosterone production.

Additional testing can include Computed Tomography (CT) or Adrenal Vein Sampling (AVS), in which an experienced radiologist, such as the professionals at Cedars-Sinai’s Hypertension Center, uses a catheter to take blood samples from both adrenal glands to measure aldosterone production.  

Treatments

When primary aldosteronism is caused by a benign tumor on the adrenal gland, the condition may be treated either surgically or with medication.

If surgery is the best option, an adrenalectomy can be performed to remove both the tumor and the adrenal gland to which it is attached. This often permanently resolves the primary aldosteronism and the physician will follow the patient’s progress closely, adjusting or eliminating the patient’s medications as needed.

When surgery is not an option, aldosterone-blocking medications can be used to manage the condition. However, these do not cure the condition and must be taken regularly to manage the symptoms.

If the primary aldosteronism is due to overactive adrenal glands, medication can help manage the condition. Medications known as mineralocorticoid receptor antagonists block the effects of aldosterone in the patient’s body and help lower blood pressure and increase potassium levels.