Primary and Secondary Hypertension Diagnosis Classification

Middle-aged overweight Hispanic woman having her blood pressure checked
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An important part of any high blood pressure diagnosis includes determining whether the disorder is “primary” or “secondary.” These two classifications refer to the underlying cause of the high blood pressure and do not have anything to do with how serious the high blood pressure is.

Primary Hypertension

The vast majority of high blood pressure diagnoses fall into the category of “primary hypertension,” also called “essential hypertension.” This classification means that your doctor or health care team is not able to locate a single cause that explains the elevated blood pressure.

Another medical term used to describe illness without obvious underlying cause is “idiopathic,” and you may hear your doctor use this term. High blood pressure is a complicated disease, with complex and often interrelated genetic and environmental factors. Thus, it is usually not possible to say for sure which elements combined to produce it.

Secondary Hypertension

A modest number of high blood pressure diagnoses are classified as “secondary hypertension.” This classification differs from a diagnosis of primary hypertension by a clearly identifiable cause of the high blood pressure. A wide variety of underlying problems can cause high blood pressure. Some important conditions include:​

  • Obstructive sleep apnea
  • Kidney problems
  • Adrenal gland tumors
  • Thyroid problems
  • Certain defects in blood vessels you're born with (congenital)
  • Certain medications, such as birth control pills, cold remedies, decongestants, over-the-counter pain relievers and some prescription drugs
  • Illegal drugs, such as cocaine and amphetamines
  • Alcohol abuse or chronic alcohol use

Risk Factors for Hypertension

High blood pressure, whether primary or secondary, has many risk factors, including:

  • Age. The risk of high blood pressure increases as you age. 
  • Race. High blood pressure is particularly common among African-Americans, often developing at an earlier age in this population than it does among Caucasians. 
  • Family history. High blood pressure tends to run in families.
  • Being overweight or obese. The more you weigh, the more blood you need to supply oxygen and nutrients to your tissues. As the volume of blood circulated through your blood vessels increases so does the pressure on your artery walls.
  • Not being physically active. People who are inactive tend to have higher heart rates. 
  • Using tobacco. Not only does smoking or chewing tobacco immediately raise your blood pressure temporarily, but the chemicals in tobacco can damage the lining of your artery walls. 
  • Too much salt (sodium) in your diet. Too much sodium in your diet can cause your body to retain fluid, which increases blood pressure.
  • Drinking too much alcohol. Over time, heavy drinking can damage your heart. Having more than two drinks a day for men and more than one drink a day for women may affect your blood pressure.
  • Stress. High levels of stress can lead to a temporary increase in blood pressure.
  • Certain chronic conditions. Certain chronic conditions also may increase your risk of high blood pressure, such as kidney disease, diabetes and sleep apnea.

Know Your Diagnosis

Because the management strategies and treatment options available depend on the underlying cause of high blood pressure, it is important to understand which type of high blood pressure you have.

If your doctor has not addressed this with you, ask him or her.