Summary

High blood pressure - also known as hypertension - describes a medical condition where the heart has to work harder to pump blood around the body and is pumping it at a higher pressure than normal through your arteries. Hypertension is a common disorder of the circulatory system, affecting around one in seven adult Australians and becoming more common with age. Over time, if left untreated, high blood pressure can weaken your heart and cause a number of health problems such as heart failure and kidney disease. It is also a major risk factor for heart attack, stroke, aneurysms and blood clots.

Hypertension usually produces no symptoms. Hereditary factors, obesity, a diet high in salt, smoking and a lack of physical activity can all contribute to hypertension. Dietary and lifestyle changes can improve blood pressure control and decrease the risk of health complications, although drug treatment is still often necessary in people for whom lifestyle changes are not enough or not effective.

How is high blood pressure defined?

Blood pressure is represented by two measurements, systolic and diastolic, which depend on whether the heart muscle is contracting (systole) or relaxed between beats (diastole). This equals the maximum and minimum pressure, respectively. Normal blood pressure at rest is within the range of 100–140 mmHg systolic (top reading) and 60–90 mmHg diastolic (bottom reading). High blood pressure is said to be present if it is often at or above 140/90 mmHg.

In most cases, the only way you'll know if you're suffering from hypertension is if your doctor measures your blood pressure over a period of time to establish if you have a persistent problem. Experts recommend that everyone should have their blood pressure checked regularly (preferably yearly).

What causes high blood pressure?

Hypertension is classified as either primary (essential) hypertension or secondary hypertension. Primary hypertension has no identifiable cause, but secondary hypertension is caused directly by an underlying health issue or as a side effect of some medications. Whilst primary blood pressure doesn't have a specific cause, there are many risk factors that can increase your chance of developing it. These include a history of hypertension in the family, eating food that's high in fat or salt, not exercising enough, being stressed, being overweight, or drinking too much alcohol.

Secondary hypertension results from an identifiable cause, with renal disease being the most common. Hypertension can also be caused by endocrine conditions, obesity, sleep apnea and pregnancy.

Certain medications can cause hypertension or make controlling hypertension more difficult. Check with your doctor or pharmacist.

Older people may experience a change in their blood pressure pattern due to their arteries becoming more rigid with age.

What are the symptoms of high blood pressure?

Whilst high blood pressure doesn't cause any obvious symptoms or immediate problems, there are a number of ways your body will respond to hypertension that could be considered warnings. The only way to know for certain is to have your blood pressure checked by a doctor.

In very rare cases, high blood pressure symptoms will include a headache, blurred vision, nosebleed and shortness of breath. If you have any of these symptoms, you should see your doctor immediately.

What treatment methods are available?

You should speak to your doctor to discuss your blood pressure. If your blood pressure is slightly higher than the ideal level of 120/80mmHg, it's likely that your doctor will advise you to make simple lifestyle changes to help reduce it. If your blood pressure sits above the indicator for hypertension, which stands at 140/90mmHg, and your doctor thinks you're at risk of developing heart disease in the next ten years, you'll be prescribed medication and advised to change your lifestyle to help lower your high blood pressure.

Lifestyle modifications

The first line of treatment for hypertension is to recommend preventative lifestyle and dietary changes, physical exercise, and weight loss. These have all been shown to significantly reduce blood pressure in people with hypertension. Two out of five people can successfully lower their blood pressure by making adjustments to their lifestyle. Their potential effectiveness is similar to and at times exceeds a single medication. If hypertension is high enough to justify immediate use of medications, lifestyle changes are still recommended in conjunction with medication.

Medications

Several classes of medications, collectively referred to as antihypertensive drugs, are available for treating hypertension. Use of these medications must be discussed with your doctor. Usually hypertensive medications are introduced at low doses. The dose may be gradually increased by your doctor if needed. A second or even a third drug may be added to achieve good blood pressure control. Any drug treatment for hypertension needs to be monitored carefully by your doctor. You should never alter the dose of your hypertension medication or stop taking it without consulting with your doctor. Medications don’t cure the condition and most of the people who need to take antihypertensive drugs will do so for the rest of their lives.

Prevention

Effective lifestyle modification may lower blood pressure as much as an individual antihypertensive drug. Combinations of two or more lifestyle modifications can achieve even better results. Some healthy lifestyle choices include: