Secondary Hypertension

What is secondary hypertension?

High blood pressure occurs when blood pushes too hard against the walls of your arteries while traveling through the body.

This extra pressure — called hypertension — can damage your organs over time. It can damage your heart, brain, eyes, lungs, and kidneys.

Doctors use the term secondary hypertension or complex hypertension to refer to high blood pressure that is caused by some other underlying disease. Your doctor may suspect secondary hypertension if your high blood pressure is not controlled with treatments that are usually effective, you suddenly develop high blood pressure, or if the blood pressure is severely elevated. This is especially true if you're under 30 or if you also have an electrolyte disorder.

Definitions of secondary hypertension

  • Resistant hypertension is when your blood pressure continues to be high, even when you are taking three or more medications designed to help control it.
  • Renal hypertension or hypertensive renal disease is what it's called when your high blood pressure is caused by an underlying kidney disease.

Causes of secondary hypertension

Secondary hypertension can have many different causes. Major causes include:

  • Some medications can cause secondary hypertension
  • Chronic kidney disease (including diabetic kidney disease)
  • Genetic kidney diseases
  • Renovascular disease (affecting the blood supply to the kidney)
  • Endocrine disorders (i.e. primary aldosteronism, pheochromocytoma, Cushing's syndrome, hyperthyroidism)
  • Obstructive sleep apnea

Complications of secondary hypertension

High blood pressure can cause a number of complications. It can be deadly if left untreated.

High blood pressure can damage the kidneys. This reduces the ability of the kidneys to clean the blood. Waste products build up in the body, causing widespread organ damage over time.

These waste products include:

  • Excess fluids
  • Salts
  • Acids
  • Hormones

Damaged kidneys also lose their ability to control blood pressure. This drives up blood pressure even higher, which causes more kidney damage and can lead to kidney failure.

How to prevent secondary hypertension

Depending on the cause of your secondary hypertension, it may be impossible to prevent. The goal of treatment is to identify a cause, so that your doctors can keep your high blood pressure under control. That way, you can avoid the impact of progressive kidney disease.

Your doctor will help you control your secondary high blood pressure by:

  • Prescribing more specialized blood pressure medication
  • Recommending changes to diet and lifestyle
  • Treating the underlying kidney disease

Why choose UPMC for renal hypertension care?

At the UPMC Kidney Disease Center, our experts:

  • Specialize in care for secondary (complex) hypertension
  • Treat the full spectrum of kidney diseases, including diabetic kidney disease, chronic kidney disease, inherited kidney disease, and glomerular disease
  • Partner with experts in endocrinology, cardiology, genetics and nutrition to provide comprehensive care

At the UPMC Kidney Disease Center, we will work with you to identify the cause of your high blood pressure and help you manage your high blood pressure to slow the progression of kidney disease.

Secondary Hypertension Symptoms and Diagnosis

Some doctors call high blood pressure a “silent killer" because you may not notice any symptoms, especially early in the process. But people with severe high blood pressure do sometimes experience:

  • Sharp headaches
  • Vision problems, like blurry or double vision
  • Nosebleeds
  • Shortness of breath or chest pain
  • Seizures

These could be signs of an emergency. Follow your doctor's instructions for dealing with hypertensive emergency if you already have high blood pressure.

Call 911 or seek emergency medical care if you don't have a high blood pressure diagnosis.

Diagnosing secondary hypertension

If your primary care doctor suspects you may have secondary hypertension, they will refer you to a nephrologist.

What a nephrologist can do is perform a specialized investigation into the potential causes of your complex hypertension. This investigation includes:

  • Asking you to regularly monitor your blood pressure at home
  • Blood tests to assess the concentration of certain substances in your blood
    • Cholesterol levels
    • Renin and aldosterone levels
    • BUN
    • Creatinine
    • Potassium
    • Creatinine clearance
  • Urine tests to check your albumin-creatinine ratio (ACR). This test measures how much protein (albumin) is in your pee.
  • One or more imaging tests, including:
    • Abdominal CT scan
    • Kidney ultrasound
    • Doppler ultrasound of the renal veins
    • Magnetic resonance angiography (MRA)
    • Renal artery angiography
  • In rare cases, you may also undergo genetic testing

By identifying the cause of your hypertension, a nephrologist can work with you to develop a personalized plan to treat your condition and get your blood pressure under control.

Secondary Hypertension Treatment

If you have secondary hypertension caused by kidney disease, your doctor will design a treatment plan that may include:

  • Lifestyle changes to manage your disease.
  • Medicine to control your high blood pressure.
  • Medicine to treat your underlying kidney disease.
  • Surgery to improve blood flow to the kidneys.

Lifestyle treatments for renal hypertensio

Your doctor will suggest lifelong heart-healthy lifestyle changes to help control your hypertensive kidney disease like:

  • Eat a healthy diet. Along with eating more fruits, veggies, and lean protein, it's vital to limit your salt intake.
  • Increase your activity level. Find a sport or other physical activity you enjoy. Commit to being active for 30 to 60 minutes most days of the week.
  • Lose weight if needed. If you're not overweight, be sure to stay at a healthy weight. If you're overweight or obese, ask your doctor how to reduce your BMI.
  • Don't smoke, and limit your intake of alcohol. Both smoking and drinking raise blood pressure. Your doctor will let you know if moderate drinking is safe for you.

Your doctor can refer you to a UPMC nutritionist or weight-loss specialist if you need help.

You'll also need to check your blood pressure often. Your doctor will let you know how and when to check it at home.

Medicine to treat secondary hypertension

Making healthy lifestyle changes are crucial for people with high blood pressure in the kidneys.

But most people who have the disease also need to take one or more drugs to control their high blood pressure:

  • Diuretics. Also known as water pills, these help your body get rid of excess sodium and water.
  • ACE inhibitors help relax blood vessels so that blood can pass through them more easily.
  • Angiotensin II receptor blockers (ARBs) block the natural chemicals that narrow blood vessels. In effect, they help relax blood vessels.
  • Calcium channel blockers help relax the muscles in your blood vessels and may also slow your heart rate.

Your doctor will help you decide the ideal mix of lifestyle changes and medical therapies to get your blood pressure to a healthy level.

Medical treatment for your underlying kidney disease

To control secondary hypertension, your underlying kidney disease will also need to be treated. These treatments are complex and will vary depending on the condition involved.

Medical treatments for kidney disease may include:

  • Drugs to control blood pressure.
  • Medicines to improve or stabilize kidney function.
  • Drugs that lower your cholesterol.
  • Supplements for iron or Vitamin D.
  • Renal supportive care, to treat the symptoms of your condition.
  • Dialysis, to help your kidneys clean waste from your blood.

Surgical treatments for renal high blood pressure

If you can't control your disease with medication, in rare cases your doctor may suggest one of two surgeries:

  • Renal stenting. In this surgery, doctors widen the kidney's veins and insert a stent. This small metal tube helps keep blood flowing to the kidneys, even when high blood pressure has damaged the arteries.
  • Renal bypass. Surgeons first harvest a vein from elsewhere in your body. They then graft the vein into place so that it improves blood flow to the kidneys.

Contact the UPMC Kidney Disease Center

To learn more about kidney disease: