Clinical features: Hypertension is elevation of blood pressure noted on at least three separate occasions. The disease processes associated with high arterial pressure are the consequences of the damage caused to the heart or to the arterial wall. The consequences of the actual level of pressure in a given person will depend not only on the measured level but also upon certain other 'risk' factors such as age, race, sex, glucose intolerance, cholesterol and smoking habit hypertension. In over 80% of hypertensive patients no specific cause is detectable, hence the name 'primary hypertension.' Hypertension can be secondary to conditions like coarctation of the aorta, renal disease, endocrine disease, EPH gestosis and due to the contraceptive pill. Hypertension is symptomless in the majority of patients. Because hypertension may result in secondary organ damage and reduced life span it should be evaluated and treated appropriately.

Definitions

Hypertension is categorized according to the level of the diastolic blood pressure (DBP) as follows:

Diagnosis

Blood pressure rises with stress e.g. when seeing a health worker. Do not diagnose hypertension on the basis of a single reading but confirm on three separate occasions. Readings should be carefully made and measured to the nearest 2 mm phase V diastolic (disappearance of sounds).

A special large cuff is needed to accurately measure BP in those in whom the sphygmomanometer bladder does not encircle the upper arm.

Points to Note

• Antihypertensive treatment is required for life in truly hypertensive patients

• Hypertension often has no symptoms: the aim of treatment is to lower the risk of end-organ damage, especially stroke

• Compliance is the most important determinant of blood pressure control. Explanation, education and minimizing side-effects of drugs are important

• Extra care should be taken with antihypertensive drugs administered to those over 60 years of age, because of increased side-effects. Lower doses are needed

• Recommend an alternative contraceptive method for women using oestrogen containing oral contraceptive

• Evidence of end organ damage, i.e. cardiomegaly, proteinuria or uraemia, retinopathy or evidence of stroke, dictates immediate treatment

• Patients should be reviewed every 1-3 months, and more often if necessary

• Urgent blood pressure reduction may precipitate stroke or blindness. It is only indicated in those patients with hypertensive crisis (see below)

• The aim of treatment is to bring the diastolic BP below 90 mm Hg, without unacceptable side effects

Management

Change in Lifestyle

These non-pharmacological measures should be applied in all hypertensive patients:

• dietary management (see below)
• regular exercise
• relaxation
• discontinuation of smoking
• avoidance of stress