How Are High Blood Pressure and Atherosclerosis Linked?

Atherosclerosis (also called atherosclerotic cardiovascular disease) is a specific type of arteriosclerosis. The two terms are often used interchangeably. There are many risk factors that may come into play when a person has atherosclerosis. One such major contributing influence is hypertension (high blood pressure), which can cause damage to the arteries and result in the restriction of blood flow to the heart and other organs and tissues of the body.

Hypertensive atherosclerosis could result in a stroke or heart attack due to a blockage or a rupture. The good news is that there are effective treatments that can help maintain normal blood pressure levels, as well as medication that may slow down the acceleration of atherosclerosis. 

What Is Atherosclerosis?

Atherosclerosis—also known as atherosclerotic cardiovascular disease—is a condition that involves a build-up of deposits that form plaques in the wall of the arteries. This build-up can eventually constrict or occlude the artery and reduce blood flow.

There are often no symptoms of atherosclerosis until an artery has become so narrow or obstructed that it can no longer supply adequate blood to organs and tissues. When this occurs in the heart, the subsequent shortage of adequate blood flow and oxygen can lead to a heart attack.

Chronic (long-term) elevation of blood pressure can speed up the process of developing atherosclerosis.

Symptoms

There are usually no outward symptoms of atherosclerotic cardiovascular disease until an occlusion of blood flow occurs. Once there is a blockage of the artery, symptoms commonly include the following.

• Pain, cramping, or muscle weakness (from mild to very severe): This can occur in the leg, arms, or other areas of the body where the blockage has occurred.
• Confusion and weakness: This could include facial drooping, speech or vision problems, headache, and dizziness, which could be a sign of stroke.
• Chest pain (angina): Chest pain is one of the basic warning signs of cardiac issues, but it's not always serious. However, if your chest pain is accompanied by pain in the shoulders, neck, or jaw, shortness of breath, nausea and vomiting, stiffness or numbness in the neck, these could be signs of a heart attack.

If you have any symptoms of a heart attack or stroke, seek emergency medical attention (such as calling 911) immediately.  

Hypertension and Atherosclerosis

There are several related processes that are believed to be involved in the development of atherosclerosis. Although hyperlipidemia—characterized by high cholesterol levels—is commonly considered the primary causative factor in atherosclerosis, hypertension (high blood pressure) often plays a significant role in its development. Furthermore, many factors that cause hypertension also play a role in the development of high cholesterol. High blood pressure is also a major factor in:

• Heart disease
• Sudden death
• Stroke
• Congestive heart failure
• Renal (kidney) insufficiency

The adverse impact of hypertension on the cardiovascular system results in an increase in tension in the walls of the arteries, which thickens the endothelium (the innermost layer of the artery) and narrows smaller arteries. This physical stress aggravates and accelerates atherosclerosis, particularly in the heart and brain.

As the arteries narrow over time, fat, cholesterol, and other substances begin to build up in what is referred to as plaque. This process is called atherosclerosis.

There is increasing scientific evidence that identifies atherosclerosis as primarily an inflammatory disease. High blood cholesterol is thought to activate the inflammatory response. 

Although hypertension is considered a risk factor for developing atherosclerosis, the exact mechanism of how high blood pressure may lend itself to the development of atherosclerosis is not very well understood.

Today, scientists are uncovering information that suggests these two disease entities—hypertension and atherosclerosis—have common mechanisms.  For example, both diseases impact the endothelium (the lining of the arterial blood vessels), which is a primary anatomical area where the disease process occurs.

More research is needed to better understand the link between hypertension and atherosclerosis.

Diagnosis

Getting a diagnosis of hypertension does not necessarily mean that a person has atherosclerosis. However, if hypertension has been undiagnosed for a long period of time or goes untreated, it can predispose a person to developing atherosclerosis.

High Blood Pressure Diagnosis

A person is diagnosed with hypertension when their blood pressure measures over 129 mmHg systolic (the top number) and over 80 mmHg diastolic (the bottom number).

High blood pressure readings must be consistent over time, because the blood pressure normally fluctuates up and down with activity and other factors. Therefore, there are specific preset parameters indicating how many times a high blood pressure reading must be to qualify for a diagnosis of high blood pressure.

There are two categories of hypertension.

• Stage 1: Systolic pressure of 130 mm Hg to 139 mm Hg or a diastolic pressure of 80 mm Hg to 89 mm Hg.
• Stage 2: Systolic pressure over 140 mm Hg or a diastolic pressure over 90 mm Hg. 

Having untreated high blood pressure of 140/90 increases the risk of getting atherosclerosis two- to three-fold.

Diagnostic Tests

Diagnostic tests for atherosclerosis include the following.

Physical exam—During a physical exam, your healthcare provider will look for signs of poor circulation, such as:

• A weak (or absent) pulse, located below the area of your artery that is blocked or narrowed.
• Cool, pale or bluish skin in the lower extremities.
• Decreased blood pressure in the arm or other area that is affected by a loss of blood flow.
• Audible sounds, called “bruits,” over the affected artery. This is usually present in occluded arteries of the neck, abdomen, or groin.

Blood tests—Some lab tests can indicate a risk for atherosclerosis even when a person has no symptoms. These may include indicators such as high cholesterol or elevated HbA1c levels (a test that indicates a person has prediabetes or diabetes). Blood glucose (sugar) levels may be checked and other lab tests performed that may indicate a possibility of atherosclerosis. 

Electrocardiogram (EKG or ECG)—A test that measures the rhythm, rate, and activity of the heart by using electrodes attached to the arms, legs, and chest. This test indicates whether a person has previously had a heart attack, or is having a heart attack presently. This test cannot be used to predict the future risk of a heart attack. 

CT or MRI angiography—These are imaging tests that involve taking a series of pictures inside the body at different angles. The images show very detailed information about different parts of the body. To diagnose atherosclerosis, a CT scan is taken of the heart to evaluate the presence of calcium deposits. Before the procedure, a dye is swallowed to enable a clear view of the organs or tissues.

MRI—An imaging test that involves strong magnetic fields and radio waves to generate detailed images. When diagnosing atherosclerosis, an MRI is used to differentiate the major components of atherosclerotic plaque.  An MRI can also be used to measure the diameter of the artery wall.

Cardiac catheterization—A procedure using a thin, hollow tube (catheter) that is inserted into a large blood vessel that leads to the heart. This allows the diagnostician to identify blocked arteries by taking X-rays using contrast dye injected through the catheter (a procedure called angiography).

Doppler ultrasound—A special device is used to measure blood pressure in various areas along the arms and legs to assess the severity of any blockages and evaluate how the blood flows through the arteries.

Cardiac stress test—A test to measure the blood supply in the coronary arteries when the heart is working (as a result of walking on a treadmill). This test is sometimes referred to as an exercise or treadmill test. A cardiac stress test may be used for diagnosis, or it may be ordered when your healthcare provider wants to recommend what level of exercise is right for you.

Echocardiogram or nuclear scans—This provides better detection of heart disease. If artery blockages are present, the EKG, echocardiogram, or nuclear scan will show characteristic abnormalities, enabling your healthcare provider to make a diagnosis of coronary artery disease.

Treatment

Although there is no cure for atherosclerosis, many things can be done to help slow down the progress of the disease. The overall preventative goal is to prevent serious narrowing of the arteries, which will prevent subsequent damage to vital organs.

Medications to control blood pressure and lower cholesterol levels are instrumental in the treatment of atherosclerosis.

Cholesterol-Lowering Medications

The most common type of medication used to lower cholesterol are statin drugs. They work by controlling the production of cholesterol in the liver. Statins are also thought to have anti-inflammatory properties, which could help reduce inflammation in the arteries.  Examples of statin drugs include:

• Lovastatin (Mevacor)
• Simvastatin (Zocor)
• Pravastatin (Pravachol)
• Fluvastatin (Lescol)
• Atorvastatin (Lipitor)
• Rosuvastatin (Crestor)

Antihypertensive Therapy

Many different types of drugs treat hypertension. Each type is differentiated according to its own category. Common types of antihypertensive drugs include the following.

• Diuretics: These help the kidney eliminate water and sodium from the body. This then lowers blood volume, which makes less fluid for the heart to circulate around the body; this, in turn, lowers blood pressure.  
• ACE inhibitors: These prevent the kidneys from retaining sodium and water by a method that deactivates an enzyme called angiotensin-converting enzyme. This results in the deactivation of a hormone called angiotensin II. Angiotensin II is known to raise blood pressure by triggering water and sodium retention while constricting the arteries.
• Angiotensin receptor blockers (ARBs): These block the hormone angiotensin II and keep the hormone from promoting salt and water retention as well as from constricting the arteries.
• Calcium-channel blockers: These slow the movement of calcium into the heart’s smooth muscle cells and coronary arteries. This results in dilatation of the arteries, thus lowering blood pressure.
• Adrenergic-receptor blockers: These drugs work by preventing neurotransmitters from attaching to cells and stimulating the heart and blood vessels. Peripheral adrenergic-receptor blockers are divided into two major groups: beta blockers and alpha blockers.        

Other Interventions

Although there is no cure yet for atherosclerosis, there are some things—in addition to taking medications—that you can do to slow down the progression of the condition. Lifestyle changes found to help slow the progression of atherosclerosis include the following.

• Quitting smoking: This is one of the most important lifestyle changes you can make.
• Maintaining a healthy weight: Body fat, particularly around the abdomen, has been linked with high cholesterol and triglyceride levels.
• Eating a healthy diet: Eating bright-colored fruits and vegetables and avoiding saturated and trans fats are good general rules of thumb. Substitute unhealthy fats with monounsaturated fats (such as olive oil), and other healthy fats, such as fat from avocados, nuts, and more. Protein sources should be from lean meat (such as skinless chicken) and fish, with an emphasis on eating fish and plant sources of protein (such as legumes).
• Exercising regularly: Regular exercise can have a significant impact on blood pressure and overall health. Be sure to consult with your healthcare provider before starting any type of exercise program.

A Word From Verywell

The takeaway is that the best course of action for atherosclerosis is to take preventative measures, such as:

• Having regular visits with your healthcare provider (including regular monitoring of your blood pressure, cholesterol levels, and other observation)
• Taking prescribed medications exactly as instructed by your healthcare provider
• Maintaining a normal blood pressure (below 120/80)
• Following your healthcare provider’s instruction on routine exercise
• Eating a healthy diet
• Quitting smoking
• Avoiding alcohol use

If you have high blood pressure—particularly along with high cholesterol levels—it’s important to see your healthcare provider regularly. Be sure to report any symptoms or changes in your health to your practitioner right away.