Hypertension or high blood pressure, is a chronic medical condition in which the blood pressure in the arteries is higher than it should be. This requires the heart to work harder than normal to circulate blood through the blood vessels.
The pressure in the arteries changes depending on what the heart is doing. When the heart contracts, pumping blood into the arteries, the pressure increases. When the heart relaxes, the pressure decreases. When blood pressure is measured, the highest pressure (when the heart is contracting) is called systole, and the lowest pressure (when the heart is relaxing) is called diastole.
Blood pressure is measured with a number followed by “mmHg”, which stands for “millimetres of mercury”. Blood pressure is written with the highest pressure first, followed by the lowest pressure. For example, someone whose highest blood pressure is 140 mmHg and whose lowest blood pressure is 90 mmHg would have their blood pressure written as 140/90.
Blood pressure is determined 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.
Types of Hypertension
Hypertension comes in two main types, called “primary” and “secondary”. Primary hypertension means that the hypertension is not caused by any other disease of the body.
Secondary hypertension means that the hypertension is caused by another disease. Various conditions and medications can lead to secondary hypertension, including:
- Kidney problems
- Adrenal gland tumors
- Thyroid problems
- Certain defects in blood vessels you’re born with (congenital)
- 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
- Alcohol abuse or chronic alcohol use
- Obstructive sleep apnea
In most cases hypertension is primary (90-95%), with only a very small amount being secondary (5-10%).
Problems Caused by Hypertension
Hypertension can lead to diseases such as heart attack, stroke, eye problems, and kidney disease. To stay healthy, most people should try to keep their blood pressure below 140/90 mmHg
Most people with high blood pressure have no signs or symptoms, even if blood pressure readings reach dangerously high levels.
Although a few people with early-stage high blood pressure may have dull headaches, dizzy spells, or a few more nosebleeds than normal, these signs and symptoms usually don’t occur until high blood pressure has reached a severe or life-threatening stage.
Hypertension can often be fixed with changes in diet or lifestyle. I recommend the following:
- Lose weight if overweight or obese
- Exercise regularly
- Reduce dietary salt intake
- Limit alcohol consumption
- Consume a diet rich in fruit and vegetables
If lifestyle changes fail, then medications are often required. The medications which are used depend on the other medical conditions which the person has. Examples of medications include:
- Diuretics, which increase urination to get rid of excess fluid
- Beta-blockers, which slow down the heart rate
- ACE inhibitors, which reduce the tightness of the arteries
Even small reductions in blood pressure can have a large effect on one’s health. For example, reducing blood pressure by 5 mmHg (e.g. from 150/100 to 145/95 mmHg) can decrease the risk of stroke by 34% and of heart disease by 21%.