What is high blood pressure?

High blood pressure means that the pressure of the blood in the arteries is too high. Physicians refer to a patient as having high blood pressure when repeat blood pressure measurements give readings of in excess of 140/90, or 140 over 90 (mmHg). In some cases, only the first or "top" number (systolic blood pressure) may be too high, while the second or "bottom" number (diastolic blood pressure) is not. There are three degrees of severity, which depend on the blood pressure readings obtained. Long-term high blood pressure may result in irreversible damage to the circulatory system. 

Possible consequences include:

• Coronary heart disease
• Heart attack
• Heart failure
• Narrowing of the carotid arteries
• Stroke
• Aortic aneurysm
• Peripheral arterial disease
• Chronic kidney damage and damage to the retina

What are the main symptoms?

High blood pressure does not usually cause any symptoms, and is usually detected by chance. However, the following symptoms of high blood pressure may develop in patients who have had the condition for a number of years:

• Headache
• Dizziness
• Nose bleeds
• Fatigue
• Flushed/red face

What are possible causes?

In most cases, the exact cause of high blood pressure is unclear. Physicians refer to these cases as primary or essential hypertension, a condition that is thought to be the result a complex interaction of different contributory factors. These include:

• Genetic predisposition
• Lack of exercise
• High salt intake
• Stress

Diagnosis of high blood pressure

Blood pressure fluctuates throughout the day and may for instance be higher when a person is nervous. A reliable diagnosis can therefore only be obtained by repeating blood pressure measurements.

Diagnostic steps:

• Repeat measurements to be taken on at least two different days. The patient should be allowed to rest for a few minutes prior to measurements being taken.
• In difficult cases, 24 hour ambulatory blood pressure monitoring
• Investigations for secondary manifestations of high blood pressure: examination of the retina, heart and kidneys

Treatment for high blood pressure

In some cases, high blood pressure may be reduced as a result of lifestyle changes. Many patients, however, will require medication.

Lifestyle modifications

Persons with high blood pressure should try to:

• Maintain regular physical activity
• Reduce weight, if overweight
• Avoid alcohol and nicotine
• Limit salt intake
• Incorporate stress-relief and relaxation into their daily routine

Particularly in cases with only mild hypertension, close adherence to these lifestyle modifications may increase the chance of successful blood pressure control. For instance, a weight loss of 5kg is often sufficient to reduce blood pressure by a value of 10 (mmHg). The effects of lifestyle modifications can usually be seen within a number months.

High blood pressure medication

If the patient's hypertension cannot be controlled by lifestyle changes alone, the physician will prescribe medications that lower blood pressure (antihypertensive drugs). While many patients will only need to take one particular drug product, some patients may require antihypertensive combination therapy. In all cases, it is important that treatment be tailored to the individual patient. It is essential that the body has time to get used to the blood pressure-lowering effects of the medication, which may take a number of weeks. In most cases, medication is needed for life.