Why hypertension increases the risk of heart disease and stroke and what to do about it

• Hypertension is the medical term for high blood pressure and it can increase the risk of heart disease, stroke, and other cardiac conditions.
• High blood pressure causes your blood vessels to thicken and become stiff, which puts stress on the heart and can lead to heart disease.
• A stroke can occur as a result of failing to treat hypertension, so it is important to be aware of your risk factors and get your blood pressure checked regularly.

Hypertension is the medical term for high blood pressure, or when blood vessels cannot relax enough and create higher resistance to blood pumping through the circulatory system. So, it plays an important role in heart health.

In fact, according to the Centers for Disease Control and Prevention about 70% of Americans who have chronic heart failure and 80% who have a stroke also have high blood pressure.

Here's what you need to know about how hypertension, heart disease, and stroke are related.

Hypertension and heart disease

When you have hypertension, your blood vessels thicken from the stress of blood forcefully rushing through them, says Icilma Fergus, MD, a cardiologist at Mount Sinai Medical Center.

Over time, this can cause the vessels to grow stiff, which makes the heart work harder to continue pumping blood through them. Putting too much stress on your heart can lead to different types of heart disease:

• Coronary artery disease. The thicker, narrow blood vessels associated with high blood pressure make it easier for plaque to build up on your artery walls. If that plaque accumulation in the arteries leading to the heart, it can cause coronary artery disease, which can result in a heart attack or heart failure. A study in India found that hypertensive adults are 11 times more likely to develop coronary artery disease.
• Heart attack. When the arteries build up with plaque, a blood clot is more likely to form. A blood clot blocks blood flow to the heart and prevents it from getting the oxygen and nutrients it needs, which damages heart muscle and results in a heart attack. About 70% of Americans having their first heart attack will also have high blood pressure.
• Heart failure. Over time, the stress of high blood pressure makes the heart larger and less efficient. This can lead to heart failure, or the condition when the heart can't provide enough blood to the body. A study in Massachusetts found that 91% of those who developed heart failure also had hypertension.

Hypertension and stroke

There are two main types of stroke: ischemic and hemorrhagic. Ischemic strokes are more common than hemorrhagic strokes (which only make up about 13% of stroke cases), but hypertension is strongly related to each type.

• Ischemic stroke. When blood clots form in arteries that lead to the brain, the result is an ischemic stroke. Without ample blood supply to brain cells, or neurons, they will stop working and heavily impair your body's most vital functions. Hypertension accounts for about 40% to 50% of ischemic strokes, says Julius Gene Latorre, MD, a vascular neurologist at Upstate University Hospital.
• Hemorrhagic stroke. In some cases, high blood pressure can cause blood vessels to burst. If a blood vessel bursts in the brain, it is called a hemorrhagic stroke, and blood may leak into the cranium and severely damage brain tissue. Research has found that hypertension increased the odds of hemorrhagic stroke by about 10 times.

Lowering blood pressure decreases the risk of heart disease and stroke

Despite the dangers of hypertension, the CDC estimates that 11 million US adults don't know they have it. You can't feel high blood pressure, which is why the American Heart Association calls it a "silent killer."

"Unless one has regular medical care and is getting checkups, you may not even be aware of having high blood pressure until unfortunately, you have had one of the unfortunate consequences," says Usman Baber, MD, a cardiologist at Icahn School of Medicine at Mount Sinai.

But there are common risk factors. According to Lattore, about 60% of people aged 60 or older have hypertension, and as you get older, it's a good idea to stay on top of your blood pressure.

Certain demographics are also prone to hypertension, Fergus says, such as African-Americans and second-generation immigrants, and you should be aware if it runs in your family.

If you do have hypertension, treating it can have a strong effect on your health. For example, research has found that reducing systolic blood pressure (the top number in your blood pressure reading) by 10 points is associated with a 50% to 60% lower risk of stroke death and a 40% to 50% lower risk of death resulting from coronary artery disease.

To treat hypertension and lower the chances of a stroke or heart disease, Fergus says you should exercise regularly, eat a low-salt and high-potassium diet, and stay away from cigarettes. For more detailed information, read our article, "How to lower blood pressure with a heart-healthy diet and exercise."

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