1. Essential or primary hypertension – Nine out of ten people with high blood pressure have this type and the exact cause is unknown, although it involves many risk factors.
2. Secondary hypertension – About 10 per cent of people have high blood pressure due to another disease, such as kidney­ disease, rare endocrine disorders or heart valve problems, or in rare cases it is due to interactions with a drug.
3. Malignant hypertension – In this rare type, blood pressure can soar to dangerous levels, requiring urgent hospital treatment.

MEASURING BLOOD PRESSURE

Doctors usually use a device called a sphygmomanometer to measure blood pressure, although some doctors now have electronic machines instead. This device has an inflatable cuff linked to a column of mercury or sprung dial. The blood pressure values are given in millimeters of mercury (written as mmHg for short).

A blood pressure reading is shown as two numbers, for example. 140/90 mmHg. The first number on the reading is the systolic pressure – the pressure when the heart attacks and when the pressure is at its highest. The second number is the diastolic pressure and corresponds to the resting and therefore the lower pressure between the heartbeats

The cuff is placed around the upper arm over the main artery – the brachial artery – and inflated to block the blood flow. The doctor places a stethoscope just below the cuff on the inside of the elbow. As the cuff is gradually deflated, blood rushes through the artery and this turbulent fleet can be heard via the stethoscope (or microphone in electronic devices). The doctor can monitor the changes in the sounds and identify the point at which the blood is flowing smoothly (through the unsquashed brachial artery), this is the diastolic pressure.

Routine blood pressure tests are vital for at-risk groups such as the elderly because hypertension may show no symptoms. High blood pressure can run in families, so if .his is the case in your family makes an appointment for a check with your doctor.

KNOW THE RISK FACTORS

High blood pressure can run in families, but doctors have identified other factors that can put you at risk of high blood pressure; some are similar to those for heart disease.

• Increasing age (as you get older, your arteries become stiffer and push your blood pressure tip).

• Being overweight.

• Excessive alcohol consumption.

• Smoking.

• High-salt diet.

Persistently high blood pressure is a common problem and it is important to treat it when it occurs because it significantly increases the risk of a stroke.

There are times when everyone’s blood pressure is high. Your blood pressure fluctuates throughout the day, being lowest during sleep then rising on getting up, and reaching its higher value sometime mid­ morning. On top of your normal values are times of stress, nervousness, excitement and physical activity – all of which raise your blood pressure.

Although people’s blood pressure has a range of values that are acceptable, doctors will consider 120/80 mmHg as a ‘normal’ reading. The first number of the reading relates to the blood pressure when the heart muscle contracts – systole – and the second number relates to pressure during its relaxation phase – diastole.