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.
Symptoms
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.
If you don't regularly see your doctor, you may be able to get a free blood pressure screening at a health resource fair or other locations in your community. You can also find machines in some stores that will measure your blood pressure for free.
Public blood pressure machines, such as those found in pharmacies, may provide helpful information about your blood pressure, but they may have some limitations. The accuracy of these machines depends on several factors, such as a correct cuff size and proper use of the machines. Ask your doctor for advice on using public blood pressure machines.
Causes
There are two types of high blood pressure.
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.
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
- Illegal drugs, such as cocaine and amphetamines
Acute Kidney Problems
If your kidneys suddenly stop working, doctors call it acute kidney injury or acute renal failure. The main causes are:
- Not enough blood flow to the kidneys
- Direct damage to the kidneys themselves
- Urine backed up in the kidneys
- Have a traumatic injury with blood loss, such as in a car wreck
- Are dehydrated and your muscle tissue breaks down, sending too much protein into your bloodstream
- Go into shock because you have a severe infection called sepsis
- Have an enlarged prostate that blocks your urine flow
- Take certain drugs or are around certain toxins
- Have complications during a pregnancy, such as eclampsia and pre-eclampsia
Those things can happen when you:
Autoimmune diseases, when your immune system attacks your body, can also cause an acute kidney injury.
Chronic Kidney Disease
When your kidneys don't work well for longer than 3 months, doctors call it chronic kidney disease. You may not have any symptoms in the early stages, but that's when it’s simpler to treat.
Diabetes (types 1 and 2) and high blood pressure are the most common culprits. High blood sugar levels over time can harm your kidneys. And high blood pressure creates wear and tear on your blood vessels, including those that go to your kidneys.
- Immune system diseases (If you have kidney disease due to lupus, your doctor will call it lupus nephritis.)
- Long-lasting viral illnesses, such as HIV/AIDS, hepatitis B, and hepatitis C
- Pyelonephritis, a urinary tract infections within the kidneys, which can result in scarring as the infection heals. It can lead to kidney damage if it happens several times.
- Inflammation in the tiny filters (glomeruli) within your kidneys. This can happen after a strep infection.
- Polycystic kidney disease, a genetic condition where fluid-filled sacs form in your kidneys
Defects present at birth can block the urinary tract or affect the kidneys. One of the most common ones involves a kind of valve between the bladder and urethra. A urologist can often do surgery to repair these problems, which may be found while the baby is still in the womb.
Drugs and toxins, such as lead poisoning, long-term use of some medications including NSAIDs (nonsteroidal anti-inflammatory drugs) like ibuprofen and naproxen, and IV street drugs can permanently damage your kidneys. So can being around some types of chemicals over time.