What causes High Blood Pressure?

High blood pressure, also known as hypertension, is a common condition that occurs when the force of blood against the artery walls is consistently higher than normal. This increased pressure can cause damage to the blood vessels, leading to serious health issues, such as heart attack, stroke and heart failure. According to the National Heart, Lung and Blood Institute, approximately 1 in 3 adults in the United States have high blood pressure and are not aware of it. Hypertension has been referred to as a ‘silent killer’ because it usually does not cause symptoms yet damage is still happening in the body. This is why it is important to have your blood pressure checked at least once a year.

There are numerous potential causes of high blood pressure, ranging from certain lifestyle factors to underlying medical conditions. Read on to explore some of the most common causes of high blood pressure.

Primary vs. Secondary Hypertension

Primary and secondary hypertension are two main types of high blood pressure, each with different causes and management approaches. Primary hypertension, also known as essential hypertension, is the most common type. Multiple factors may contribute to a person's risk of developing primary hypertension, such as obesity, a sedentary lifestyle, excessive salt intake and high levels of stress.

Secondary hypertension, on the other hand, is less common and is caused by an underlying medical condition or medication. Unlike primary hypertension, secondary hypertension can often be traced to specific diseases or disorders affecting the kidneys, arteries, heart or endocrine system. Once the underlying cause is diagnosed and treated, blood pressure usually returns to normal or improves.

Potential Causes of High Blood Pressure

The causes of high blood pressure may include medical conditions and medications. An individual may also have various risk factors that increase their chance of developing high blood pressure.

Genetics and Age

Genetics may play a role in the development of high blood pressure. Individuals with a family history of high blood pressure are more likely to develop this condition. Genetic factors are inherent and cannot be controlled, which makes them unmodifiable risk factors.

Age is another unmodifiable risk factor for hypertension. As a person gets older, the risk of developing high blood pressure may increase. This is partly because the arteries may become stiffer and narrower, causing an increased resistance to blood flow. As a result, the heart has to work harder to pump blood, leading to increased pressure within the blood vessel.

Medical Conditions

Several medical conditions can contribute to high blood pressure. Medical conditions that may cause high blood pressure include the following :

• Kidney disease: The kidneys help regulate the amount of sodium and water in the body. When the kidneys are not working properly, sodium and water levels can increase, leading to higher blood pressure.
• Sleep apnea: Sleep apnea is a disorder in which breathing repeatedly stops and starts during sleep. Sleep apnea can disrupt sleep and causes a drop in oxygen level which increases blood pressure and strains the cardiovascular system. and activate the sympathetic nervous system, which may lead to high blood pressure.
• Thyroid disorders: Both hyperthyroidism (an overactive thyroid) and hypothyroidism (an underactive thyroid) can affect blood pressure. Hyperthyroidism may cause high blood pressure due to an increased heart rate and increased blood volume, while hypothyroidism can cause high blood pressure due to increased resistance of blood vessels.
• Pregnancy: Some women can develop hypertension during pregnancy, known as gestational hypertension. If not managed, it can progress to preeclampsia, a severe condition that poses risks to both the mother and fetus. Some women with gestational hypertension are at higher risk of developing chronic hypertension in the future.
• Pheochromocytoma: A rare tumor of the adrenal glands that can release excessive amounts of hormones, such as adrenaline. This results in episodes of high blood pressure, which can be severe.
• Cushing syndrome: This condition is caused by prolonged exposure to high levels of the hormone cortisol, either due to excessive production by the body or from taking corticosteroid medications. High cortisol levels can narrow the arteries, which can raise blood pressure.

Medications

Several medications can contribute to high blood pressure. These medications may include the following:

• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• Corticosteroids
• Some antidepressants
• Decongestants
• Oral contraceptives
• Stimulants (e.g., amphetamines, methylphenidate)
• Immunosuppressants
• Erythropoietin (used in treating anemia)
• Certain herbal supplements (e.g., licorice, ephedra/ma huang)
• Caffeine (in high doses)
• Migraine medications

Those with or at high risk of blood pressure should consult a healthcare provider before starting a new medication. Various medications may lead to secondary hypertension or complicate the treatment of pre-existing high blood pressure.

Lifestyle Factors

Lifestyle factors may also affect the risk of developing high blood pressure. These lifestyle factors include:

• Sedentary lifestyle: Minimal physical activity is often linked to high blood pressure. Regular physical activity can help strengthen the heart, enabling it to pump blood more efficiently.
• Diet: Consuming too much salt, saturated fats and processed foods can elevate blood pressure. On the other hand, a balanced diet rich in fruits, vegetables, whole grains, lean proteins and low-fat dairy products may help maintain healthy blood pressure levels.
• Weight: Carrying excess weight can put additional strain on the heart, causing it to work harder to pump blood throughout the body. As a result, the pressure on the arteries may increase.
• Smoking: The chemicals in tobacco can damage the heart and blood vessels, leading to the narrowing of the arteries (atherosclerosis), which in turn can elevate blood pressure. Additionally, nicotine, a primary compound in tobacco, raises heart rate and makes blood vessels constrict, both of which can contribute to higher blood pressure.
• Alcohol: Excessive or chronic alcohol consumption can increase blood pressure. Limiting alcohol intake may help lower the risk of developing hypertension.

A combination of these lifestyle factors may affect an individual's risk for developing high blood pressure. However, making healthy lifestyle changes may help individuals lower their risk and lead a healthier life.

Sources:

• https://www.nhlbi.nih.gov/health/high-blood-pressure
• https://medlineplus.gov/ency/article/000468.htm
• https://medlineplus.gov/ency/article/000155.htm
• https://www.mayoclinic.org/diseases-conditions/prehypertension/symptoms-causes/syc-20376703
• https://www.hsph.harvard.edu/nutritionsource/healthy-drinks/drinks-to-consume-in-moderation/alcohol-full-story/#Dark_side_alcohol