DIABETES AND ENDOCRINE SYSTEM Endocrine System • Graves' disease • Hypoglycemia • Goiter • Male hypogonadism • Gestational diabetes • Type 1 diabetes • Hyperthyroidism • Hypothyroidism • Addison's disease • Hyperparathyroidism • Diabetic retinopathy • Cushing's syndrome • Acromegaly • Hypopituitarism • Thyroid nodules • Metabolic syndrome • Prolactinoma • Pituitary tumors • Dehydration • Primary aldosteronism • Hashimoto's disease • Pheochromocytoma • Type 2 diabetes • Prediabetes • Diabetic coma • Diabetic hyperosmolar syndrome • Diabetic ketoacidosis • Diabetes insipidus

Note: All links within content go to MayoClinic.com

Though your adrenal glands are each only about half the size of your thumb, these tiny titans dictate much of what happens in your body. Perched atop each of your kidneys, they produce hormones that help regulate your metabolism, immune system, blood pressure and other essential functions. One such hormone is aldosterone, which manages your body's balance of sodium, potassium and water. In primary aldosteronism, your body produces too much of this hormone, causing you to retain sodium and lose potassium.

Sodium and potassium normally work together to help maintain the right balance of fluids in your body, transmit nerve impulses, and contract and relax your muscles. But excess aldosterone causes sodium retention, which in turn attracts and holds excess water, increasing your blood volume and blood pressure.

Doctors once considered primary aldosteronism rare. However, as screening for this condition becomes more common, evidence is emerging that it may be responsible for as many as one in 10 cases of high blood pressure. The condition is especially common in people with severe, uncontrolled high blood pressure. Treatment depends on the underlying cause, but effective surgery and medications are available.

High blood pressure that doesn't respond completely to medication is the most common sign of primary aldosteronism.

Less common signs and symptoms of this condition may include:

• Headache
• Muscle weakness and cramps
• Fatigue
• Temporary paralysis
• Numbness
• Pricking, tingling sensation
• Excessive thirst
• Excessive urination

A noncancerous (benign) growth (aldosteronoma) in an adrenal gland — a condition also known as Conn's syndrome — is the most common known cause of primary aldosteronism.

Other causes include:

• Overactivity of both adrenal glands (bilateral hyperplasia)
• Rarely, cancerous (malignant) growths in the outer layer (cortex) of the adrenal gland
• Rarely, genetic mutations

Most people with high blood pressure don't have primary aldosteronism. You're at increased risk of this condition if you have high blood pressure and at least one of the following signs:

• Potassium deficiency (hypokalemia)
• Poorly controlled high blood pressure, despite having tried multiple medications
• A benign growth on your adrenal gland
• Thickening of the wall of the left pumping chamber of your heart (left ventricular hypertrophy)

A rare type of primary aldosteronism called glucocorticoid-remediable aldosteronism (GRA) runs in families. This condition may cause high blood pressure in children and young adults. Genetic testing can identify people at risk.

If you have any of the following signs or symptoms, see your doctor:

• Persistent tingling sensation
• Muscle cramps and weakness not explained by physical activity
• Temporary paralysis
• Unexplained, excessive thirst or urination

Have your blood pressure checked regularly in order to catch high blood pressure in its early stages, before serious damage occurs to your heart. Have a screening at least every two years, depending on your current health, medical history and other risk factors for cardiovascular disease. Ask your doctor about the best interval for you.

Your doctor may first suspect primary aldosteronism if you have high blood pressure and low blood potassium, but many people with this condition — especially those in the early stages of the disease — have normal potassium levels.

To diagnose primary aldosteronism, your doctor may measure the levels of aldosterone and renin in your blood. Renin is an enzyme released by your kidneys that helps regulate blood pressure. Many people with high blood pressure have low renin levels, but few also have the very high aldosterone levels that point to primary aldosteronism.

Dietary sodium, posture, blood potassium levels and certain medications can alter the results of this test. Your doctor will recommend a number of changes before the test to control these factors, including following a low-sodium diet, taking medications to control your potassium levels, and adjusting your current medications to eliminate those that can interfere with test results.

To confirm the diagnosis, your doctor also may attempt to suppress your aldosterone levels by artificially increasing your sodium levels. If you have primary aldosteronism, your aldosterone levels will remain high. Your doctor may use one of three tests:

• Oral salt loading. You'll follow a high-sodium diet for three days before your doctor measures aldosterone and sodium levels in your urine.
• Saline loading. Your aldosterone levels are tested after sodium mixed with water (saline) is infused into your bloodstream for several hours.
• Fludrocortisone suppression test (FST). After you've followed a high-sodium diet and taken fludrocortisone — which mimics the action of aldosterone — for three days, aldosterone levels in your blood are measured.

If you receive a diagnosis of primary aldosteronism, your doctor will run additional tests to determine whether the underlying cause is an aldosteronoma or overactive adrenal glands. Tests may include:

• Abdominal computerized tomography (CT) scan. A CT scan can help identify a tumor on your adrenal gland or an enlargement that suggests overactivity. This imaging test may miss small but important abnormalities, so you may need further testing.
• Adrenal vein sampling. This is the most reliable test for determining the cause of primary aldosteronism. A radiologist draws blood from both your right and left adrenal veins and compares the two samples. Aldosterone levels that are significantly higher on one side indicate the presence of an aldosteronoma on that side. Aldosterone levels that are similar on both sides point to overactivity in both glands.

Untreated high blood pressure may lead to heart attack, heart failure, stroke, kidney failure, dementia, visual impairment and premature death.

Adrenal vein sampling increases your risk of a blood clot (thrombosis) developing at the site where blood is drawn. If your doctor recommends this test, be sure it's performed by an experienced radiologist.

Treatment for primary aldosteronism depends on the underlying cause.

Bilateral adrenal hyperplasia
A combination of medications and lifestyle modifications can effectively treat primary aldosteronism caused by overactive adrenal glands.

• Medications. Mineralocorticoid receptor antagonists block the action of aldosterone in your body. Your doctor may first prescribe spironolactone (Aldactone). This medication helps correct high blood pressure and low potassium, but it may cause problems. In addition to blocking aldosterone receptors, spironolactone blocks androgen and progesterone receptors and may inhibit the action of these hormones. Side effects may include male breast enlargement (gynecomastia), decreased libido, impotence, menstrual irregularities and gastrointestinal distress.

  Another mineralocorticoid receptor antagonist called eplerenone acts just on aldosterone receptors, eliminating the sex-hormone side effects associated with spironolactone. Researchers are comparing the two drugs in clinical studies, but they don't yet know whether eplerenone manages blood pressure and potassium levels as well as spironolactone does. Your doctor may recommend eplerenone if you experience serious side effects with spironolactone.

• Lifestyle changes. All high blood pressure medications are more effective when combined with a healthy diet and lifestyle. Work with your doctor to create a plan to reduce the sodium in your diet and maintain a healthy body weight. Getting regular exercise, limiting your alcohol intake and stopping smoking also may improve your response to medications.

Aldosteronoma
Primary aldosteronism caused by a benign tumor on your adrenal gland also can be effectively treated with mineralocorticoid receptor antagonists and lifestyle changes. However, high blood pressure and low potassium will return if you stop taking your medications.

Surgical removal of the adrenal gland containing the aldosteronoma (adrenalectomy) may permanently resolve both high blood pressure and potassium deficiency. Some people continue to have less severe high blood pressure after surgery, especially if they had chronic, uncontrolled high blood pressure before. Medications can help manage this condition.

Blood pressure usually drops gradually after an adrenalectomy. Your doctor will follow you closely after surgery and progressively adjust or eliminate your high blood pressure medications.

Effective treatments are available for primary aldosteronism, but don't count on these therapies keeping your blood pressure low on their own. A healthy lifestyle is essential for maintaining long-term heart health. Take these steps:

• Follow a healthy diet. Limit the sodium in your diet by focusing on fresh foods and reduced-sodium products, avoiding condiments, and removing salt from recipes. Diets that also emphasize a healthy variety of foods, including grains, fruits, vegetables and low-fat dairy products, can promote weight loss and help to lower blood pressure. Try the Dietary Approaches to Stop Hypertension (DASH) diet — it has proven benefits for your heart.
• Achieve a healthy weight. If your body mass index (BMI) is 25 or more, losing as few as 10 pounds may reduce your blood pressure.

• Exercise. Regular aerobic exercise seems to lower blood pressure in some people, even without weight loss. You don't have to hit the gym — walking vigorously for 30 minutes most days of the week can significantly improve your health. Try walking with a friend at lunch instead of dining out.
• Don't smoke. If you smoke, stop. Nicotine in tobacco makes your heart work harder by temporarily constricting your blood vessels and increasing your heart rate and blood pressure. Talk to your doctor about medications that can help you stop smoking.
• Limit alcohol and caffeine. Both substances can raise your blood pressure, and alcohol can interfere with the effectiveness of some blood pressure medications. Ask your doctor whether moderate alcohol consumption is safe for you.