What causes hypertension?

The kidneys help balance salt and fluid, so chronic kidney disease can contribute to higher pressure. Obesity can increase the work required by the heart and may alter the body signals that control blood vessels. Obstructive sleep apnoea causes repeated pauses in breathing during sleep; the resulting stress responses can push pressure upward. These conditions can contribute to hypertension, but having one does not determine how severe your blood pressure will be.

Some people have hypertension without one clear cause. Family tendency, salty foods, alcohol, smoking, low activity, stress and certain medicines can all contribute. Blood pressure can also vary with pain, illness, poor sleep or the timing of a reading.

Arrange a blood pressure review if readings remain high or a clinician has advised follow-up. Bring home readings, a list of medicines and supplements, and details about sleep, activity, alcohol and smoking. A clinician may repeat measurements and assess the kidneys, weight, sleep symptoms and other factors before deciding whether treatment is needed.

Do not stop prescribed medicine because a reading improves. Practical changes such as reducing salty processed foods, being active within your abilities, avoiding smoking and moderating alcohol can support blood-pressure care.

Seek urgent medical help for very high blood pressure accompanied by chest pain, severe breathlessness, weakness on one side, confusion, fainting or a sudden severe headache. Without those symptoms, contact a clinician promptly if repeated readings are high, especially during pregnancy or when you have kidney disease.

Ask whether your readings need confirmation outside the clinic, whether kidney tests or a sleep assessment are appropriate, and which medicines or supplements could be contributing. You can also ask which blood-pressure target and home-monitoring plan fit your health.