Diastolic Hypertension: What You Need to Know

Of the two numbers that measure your blood pressure, the second (or lower) one indicates your blood pressure between heartbeats. That's your diastolic pressure. If it's higher than normal, you have diastolic hypertension and need treatment, just as you would for any type of high blood pressure.

Read more: What Is Normal for Blood Pressure?

Your blood pressure is the force of blood flowing through your arteries, which are the blood vessels that carry blood away from your heart. This pressure is measured in millimeters of mercury (mmHg).

Normal blood pressure is less than 120 over 80, and high blood pressure is 140 over 90 or higher, according to the American Heart Association (AHA). Your doctor could diagnose you with stage 1 hypertension if your diastolic pressure is consistently 80 to 90, or your systolic blood pressure (the first or top number) is 130 to 139.

Systolic pressure is higher because it occurs during the force of a heartbeat. Diastolic pressure is lower because it occurs when your heart is resting between beats.

"It is unusual to have high diastolic blood pressure without having high systolic blood pressure," says Michael Bungo, MD, a professor of cardiovascular medicine at McGovern Medical School and UTHealth in Houston. "If you do have only diastolic hypertension, it may still increase your risk for heart attack and stroke because there is still too much stress on your blood vessels." Simply put, if your diastolic number is elevated, you have hypertension, Dr. Bungo says.

Treating hypertension is important because it may prevent a stroke or heart attack, kidney disease or heart failure, according to the Cleveland Clinic, and treatment with lifestyle changes generally starts any time someone's blood pressure is consistently higher than 120 over 80. "Even for patients with stage 1 hypertension, treatment usually starts with lifestyle changes before medications," says Dr. Bungo.

Recommended lifestyle changes, says the Cleveland Clinic, include the following:

• Losing weight if you're overweight and maintaining a healthy weight.
• Not smoking.
• Eating a diet low in salt, saturated fat and sugar and high in fruits and vegetables, whole grains and low-fat dairy.
• Exercising for at least 30 minutes every day or on most days of the week.
• Limiting alcohol to two drinks a day for men, one drink a day for women.

"There is no such thing as a best medication for hypertension that fits everyone," Dr. Bungo explains. "The choice has to be made based on how high the blood pressure is and other conditions called comorbidities. For example, patients with asthma may not be able to take some medications. Patients with kidney disease may do better on some medications. There are no set guidelines."

If lifestyle changes have failed to lower your blood pressure to 140 over 90 or less, your doctor may consider starting you on a blood pressure medication. "You may decide to start at a blood pressure of 130 over 90 in someone who has other risk factors for stroke and heart disease, such as diabetes," says Dr. Bungo.

According to the Cleveland Clinic, drug treatment for high blood pressure often starts with a diuretic. This type of medication, also called a water pill, reduces blood pressure by increasing urine output. Other drugs, called first-line drugs, may also be an early choice. These include a different type of drug, called an ACE inhibitor. People with diabetes are often started on an ACE inhibitor.

For people who do not respond well to a first-line drug for high blood pressure, another drug may be tried or added. Other common options include angiotensin II receptor blockers (ARBs), beta-blockers and calcium channel blockers, according to the Cleveland Clinic. Each of these options has its own set of risks and benefits that depend on your age, blood pressure, medical history and other risk factors.

People with hypertension usually have no symptoms, notes the American Heart Association. That's why hypertension is known as the "silent killer." The only way to find out if you have it is to have your blood pressure checked regularly.

Read more: About High Blood Pressure & Low Pulse