High blood pressure (hypertension) is a medical condition which can be caused by a number of factors. Up to 30% of adults have high blood pressure, but many aren't aware of it. Inherited and lifestyle factors may affect whether you have high blood pressure, which can also be linked to other conditions. High blood pressure may be a result of another condition, and can increase the risk of others.
Blood pressure is the measurement of how hard your blood pushes against the walls of your arteries. If this pressure is too high then this can put too much force on the walls of the arteries and the heart.
Blood pressure is measured in millimeters of mercury (mmHg) with two numbers. For example, a healthy blood pressure reading is 120/80 mmHg.
The first (and larger) of the two numbers is the systolic blood pressure. This is the pressure when your heart beats. The second number is the diastolic pressure. This is the pressure when your heart is at rest.
Blood pressure is considered to be high if two readings (on separate occasions) read 140/90 mmHg or higher.
Risk Factors and Complications
There are several factors which may put you at greater risk of developing high blood pressure (also called hypertension). These may be lifestyle related or inherited. These include:
- Family history of high blood pressure
- Lack of exercise
- High salt diet
- Consuming excess alcohol and caffeine
- Being of African or Carribean descent
- Lack of fresh fruit and vegetables
High blood pressure may be a result of another medical condition or medication. Here are some examples:
- Kidney disease
- Anti-inflammatory medications such as Ibuprofen
- Oral contraceptives
- Recreational drugs such s cocaine and amphetamines
- Herbal remedies
Having high blood pressure can mean you are more likely to suffer other medical problems, especially with the cardiovascular system. Examples include:
Blood pressure is measured using a device known as a Sphygmomanometer. These can be either manual or digital. Blood pressure readings should be taken in a seated position, with the arm resting on a desk/table and after a period of at least 5 minutes rest.
Manual sphygmomanometers consist of a stethoscope, cuff, dial, pump, and valve. The arm cuff is positioned around the upper arm and pumped up to restrict blood flow into the forearm and hand. The pressure is released (by turning the valve) slowly whilst the Doctor or nurse takes two readings from the dial.
The first reading is taken when a pulse is heard through the stethoscope (this is the systolic reading). The second reading is taken when the pulse sound stops (this is diastolic)
Digital sphygmomanometers are a lot simpler to use and can be bought in chemists and supermarkets for monitoring blood pressure at home. They simply comprise a cuff attached to the machine. The cuff is wrapped around the upper arm as before and then the machine is turned on to do the inflating and deflating automatically and come out with a precise reading.
A blood pressure reading of 120/80 is considered normal. Hypertension (high b.p.) is considered to be a measurement of about 140 systolic. It is also possible to have low blood pressure (hypotension), which is a reading below 90/60 mmHg.
If your reading comes up as high, it is usually advisable to check again on a separate occasion as blood pressure can be affected by a number of factors including anxiety and stress.
Treatment of High Blood Pressure
In cases of moderately high blood pressure, treatment usually involves simple lifestyle changes such as losing weight, reducing alcohol and caffeine intake, regular exercise and stopping smoking.
For more severe cases, medication may be required. You may be prescribed more than one type of medication to treat your blood pressure. These are the most common forms of blood pressure lowering medication;
ACE Inhibitors - reduce blood pressure by relaxing the artery walls.
Calcium channel blockers - stop calcium from entering the heart muscle and blood vessels which widens the arteries.
Beta-blockers - make the heart beat slower and with less force to reduce b.p.
Alpha blockers - relax the blood vessel walls, making it easier for blood to flow through
As with all medications, there is a risk of side-effects. These may include a skin rash, a dry cough, kidney (lower back) pain, feeling drowsy, dizzy or lightheaded. If you notice any of these symptoms, talk to your Doctor.