What is High Blood Pressure?
Blood pressure is the force of blood pushing against blood vessel walls. It is measured in millimeters of mercury (mm Hg).
High blood pressure (HBP) means the pressure in your arteries is higher than it should be. Another name for high blood pressure is hypertension.
Blood pressure is written as two numbers such as 112/78 mm Hg. The top (systolic) number is the pressure when the heart beats. The bottom (diastolic) number is the pressure when the heart rests between beats.
Normal blood pressure is below 120/80 mm Hg. If you're an adult and your systolic pressure is 120 to 129, and your diastolic pressure is less than 80, you have elevated blood pressure. High blood pressure is a systolic pressure of 130 or higher, or a diastolic pressure of 80 or higher, that stays high over time.
High blood pressure usually has no signs or symptoms. That's why it is so dangerous. But it can be managed.
Nearly half of the American population over age 20 has HBP, and many don't even know it. Not treating high blood pressure is dangerous. High blood pressure increases the risk of heart attack and stroke.
Make sure you get your blood pressure checked regularly and treat it the way your health care provider advises.
Am I at risk for developing HBP?
There are risk factors that increase your chances of developing HBP. Some of you can control, and some of you can't.
Those that can be controlled are:
Cigarette smoking and exposure to secondhand smoke
Being obese or overweight
Unhealthy diet (high in sodium, low in potassium, and drinking too much alcohol)
Factors that can't be modified or are difficult to control are:
Family history of high blood pressure
Chronic kidney disease
Obstructive sleep apnea
Socioeconomic status and psychosocial stress are also risk factors for HBP. These can affect access to basic living needs, medication, health care providers, and the ability to adapt lifestyle changes.
How can I tell if I have it?
The only way to know if you have high blood pressure is to get it checked regularly by your health care provider. For proper diagnosis of HBP, your health care provider will use an average based on two or more readings obtained on two or more visits.
What can I do about HBP?
• Don’t smoke and avoid secondhand smoke.
• Reach and maintain a healthy weight.
• Eat a healthy diet that is low in saturated and trans fats and rich in fruits, vegetables, whole grains and low-fat dairy products. Aim to consume less than 1,500 mg/day of sodium (salt). Even reducing your daily intake by 1,000 mg can help.
• Eat foods rich in potassium. Aim for 3,500 – 5,000 mg of dietary potassium per day.
• Limit alcohol to no more than one drink per day if you’re a woman or two drinks a day if you’re a man.
• Be more physically active. Aim for 150 minutes of moderate-intensity physical activity or at least 75 minutes of vigorous physical activity per week, or a combination of both, spread throughout the week. Add muscle-strengthening activity at least two days per week for more health benefits.
• Take medicine the way your health care provider tells you.
• Know what your blood pressure should be and work to keep it at that level.
High Blood Pressure and Stroke
How does high blood pressure increase stroke risk?
High blood pressure is the single most important risk factor for stroke because it’s the leading cause of stroke.
HBP adds to your heart’s workload and damages your arteries and organs over time. Compared to people whose blood pressure is normal, people with HBP are more likely to have a stroke.
About 87 percent of strokes are caused by narrowed or clogged blood vessels in the brain that cut off the blood flow to brain cells. This is an ischemic stroke. High blood pressure causes damage to the inner lining of the blood vessels. This adds to any blockage that is already within the artery wall.
About 13 percent of strokes occur when a blood vessel ruptures in or near the brain. This is a hemorrhagic stroke. Chronic HBP or aging blood vessels are the main causes of this type of stroke. HBP puts more pressure on the blood vessels until they can no longer maintain the pressure and the blood vessel ruptures over time.