High Blood Pressure Causes

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Nearly half of US adults (108 million, or 45%) have high blood pressure or “hypertension.” The CDC defines this as systolic blood pressure (SBP) reading of 130 mmHg or greater or diastolic blood pressure (DBP) reading of 80 mmHg or greater (at rest or while taking blood pressure medication). The American Heart Association laid out these guidelines in 2017. But with such large numbers of people with high blood pressure, what are the causes behind this endemic problem?

In the past, rates of high blood pressure were lower because the definition of high blood pressure was “over 140/90 mmHg.”

High blood pressure is a “primary” or “essential” hypertension when the underlying causes are unknown. When it’s due to a medical problem, it’s “secondary” hypertension.

Whether the high blood pressure is primary or secondary, keeping your blood pressure within healthy ranges is vital to prevent problems like heart diseases and strokes. This is why it’s important to live a healthy life and take drugs given by your doctor. You should also check your blood pressure at home and have follow-ups with your doctor often.

Primary (Essential) Hypertension

Most of the time, the exact causes of high blood pressure are not known. This is called primary high blood pressure. Most cases of high blood pressure (85%) are in this category.

Risk Factors 

However, there are known risk factors that can make a person more likely to get primary high blood pressure.

  • Family history – If your parents or other close relatives have high blood pressure, you are at a greater risk of having it as well.
  • Age and sex – Blood pressure increases with age because blood vessels become less flexible. Men are more likely than women to develop high blood pressure until age 64. After age 65, women are at higher risk.
  • Race – According to the American Heart Association, African Americans are at higher risk of getting high blood pressure in comparison to other races. Certain drugs may not work as well.
  • Lifestyle – High blood pressure is more likely to occur if you follow a Western-type diet, which is high in salt, unhealthy fats, refined sugars, and highly processed foods. Sedentary life increases the risk of high blood pressure. Staying active can help prevent or better manage blood pressure.
  • Weight – Having a poor diet and lack of exercise are independent risk factors for high blood pressure. Smoking and high amounts of drinking correlate with a greater risk for high blood pressure, heart diseases, and cancer. 
  • Other medical problems – Problems like diabetes, high cholesterol, and fatty liver make it more likely that you will get high blood pressure.
  • Stress – Stress activates the sympathetic nervous system, or the “fight or flight” response, which increases blood pressure and heart rate. Stress also makes a person more likely to eat bad foods, drink, smoke, and avoid exercise.

How To Prevent Or Manage Primary High Blood Pressure

Pay attention to the factors you can control and change. Don’t smoke, avoid drinking too much, work out often, eat a healthy diet, and maintain a healthy weight. Low carb diets, the DASH diet, and the Mediterranean diet are all great choices for people with high blood pressure. 

For stress control, find a practice that you enjoy, so you can use it often. Mindfulness meditation, yoga, and tai chi can all help reduce your stress levels and improve high blood pressure.

Secondary Hypertension

Secondary hypertension can have multiple causes. For example, it can be due to medical problems affecting the kidneys (i.e. chronic glomerulonephritis, polycystic renal disease, or obstructive uropathy), heart, and arteries (i.e. coarctation of the aorta). It can also be due to hormone imbalances (i.e. primary aldosteronism, hypo-, or hyper-hypothyroidism). It can even happen during pregnancy or due to drugs like NSAIDs or corticosteroids. Sleep apnea can cause it as well.

It’s vital to get the right diagnosis from your doctor because treating this form of high blood pressure requires treating the right problem. Your doctor can prescribe certain drugs (like antihypertensive drugs) to help reduce the risk of heart diseases, stroke, and kidney failure. 

Secondary Hypertension Signs And Symptoms 

Just like primary high blood pressure, secondary high blood pressure often does not cause symptoms unless the blood pressure is very high. In this case, a person may have extreme fatigue, nosebleeds, trouble breathing, irregular heartbeats, severe headache, or dizziness. 

A doctor may suspect secondary high blood pressure when the blood pressure:

  • does not improve with drugs (a condition called “resistant” hypertension)
  • when the blood pressure is too high (an SBP over 180 mmHg and a DBP over 120 mmHg)
  • if there is no family history of high blood pressure
  • when there is no obesity, which is a risk factor that suggests primary high blood pressure
  • if there is a sudden onset of high blood pressure before age 30 or after 55 years of age (primary high blood pressure often occurs between 30-55 years of age). 

You can manage secondary high blood pressure better if you adopt a healthy diet, deal well with stress, stay fit, and work out often.