High blood pressure is a common condition in which the long-term force of the blood against your artery walls is high enough that it may eventually cause health problems, such as heart disease.
Blood pressure is determined both by the amount of blood your heart pumps and the amount of resistance to blood flow in your arteries. The more blood your heart pumps and the narrower your arteries, the higher your blood pressure.
You can have high blood pressure (hypertension) for years without any symptoms. Even without symptoms, damage to blood vessels and your heart continues and can be detected. Uncontrolled high blood pressure increases your risk of serious health problems, including heart attack and stroke.
High blood pressure generally develops over many years, and it affects nearly everyone eventually. Fortunately, high blood pressure can be easily detected. And once you know you have high blood pressure, you can work with your doctor to control it.
Most people with high blood pressure have no signs or symptoms, even if blood pressure readings reach dangerously high levels.
A few people with high blood pressure may have headaches, shortness of breath or nosebleeds, but these signs and symptoms aren’t specific and usually don’t occur until high blood pressure has reached a severe or life-threatening stage.
When to see a doctor
You’ll likely have your blood pressure taken as part of a routine doctor’s appointment.
Ask your doctor for a blood pressure reading at least every two years starting at age 18. If you’re age 40 or older, or you’re 18 to 39 with a high risk of high blood pressure, ask your doctor for a blood pressure reading every year.
Blood pressure generally should be checked in both arms to determine if there’s a difference. It’s important to use an appropriate-sized arm cuff.
Your doctor will likely recommend more frequent readings if you’ve already been diagnosed with high blood pressure or have other risk factors for cardiovascular disease. Children age 3 and older will usually have blood pressure measured as a part of their yearly checkups.
There are two types of high blood pressure.
1. Primary (essential) hypertension
For most adults, there’s no identifiable cause of high blood pressure. This type of high blood pressure, called primary (essential) hypertension, tends to develop gradually over many years.
2. Secondary hypertension
Some people have high blood pressure caused by an underlying condition. This type of high blood pressure, called secondary hypertension, tends to appear suddenly and cause higher blood pressure than does primary hypertension. Various conditions and medications can lead to secondary hypertension, including:
- Obstructive sleep apnea
- Kidney problems
- Adrenal gland tumors
- Thyroid problems
- Certain defects you’re born with (congenital) in blood vessels
- Certain medications, such as birth control pills, cold remedies, decongestants, over-the-counter pain relievers and some prescription drugs
High blood pressure has many risk factors, including:
- Family history
- Being overweight or obese
- Not being physically active
- Using tobacco
- Too much salt (sodium) in your diet.Too much sodium in your diet can cause your body to retain fluid, which increases blood pressure.
- Too little potassium in your diet. Potassium helps balance the amount of sodium in your cells. If you don’t get enough potassium in your diet or retain enough potassium, you may accumulate too much sodium in your blood.
- High levels of stress can lead to a temporary increase in blood pressure. If you try to relax by eating more, using tobacco or drinking alcohol, you may only increase problems with high blood pressure.
Sometimes pregnancy contributes to high blood pressure, as well.
Although high blood pressure is most common in adults, children may be at risk, too. For some children, high blood pressure is caused by problems with the kidneys or heart. Poor lifestyle habits, such as an unhealthy diet, obesity and lack of exercise, contribute to high blood pressure.
The excessive pressure on your artery walls caused by high blood pressure can damage your blood vessels, as well as organs in your body. The higher your blood pressure and the longer it goes uncontrolled, the greater the damage.
Uncontrolled high blood pressure can lead to complications including:
- Heart attack or stroke.High blood pressure can cause hardening and thickening of the arteries (atherosclerosis), which can lead to a heart attack, stroke or other complications.
- Increased blood pressure can cause your blood vessels to weaken and bulge, forming an aneurysm. If an aneurysm ruptures, it can be life-threatening.
- Heart failure.To pump blood against the higher pressure in your vessels, the heart has to work harder. This causes the walls of the heart’s pumping chamber to thicken (left ventricular hypertrophy). Eventually, the thickened muscle may have a hard time pumping enough blood to meet your body’s needs, which can lead to heart failure.
- Weakened and narrowed blood vessels in your kidneys.This can prevent these organs from functioning normally.
- Thickened, narrowed or torn blood vessels in the eyes.This can result in vision loss.
- Trouble with memory or understanding.Uncontrolled high blood pressure may also affect your ability to think, remember and learn. Trouble with memory or understanding concepts is more common in people with high blood pressure.
- Dementia: Narrowed or blocked arteries can limit blood flow to the brain. A stroke that interrupts blood flow to the brain also can cause vascular dementia.