Blood pressure is the amount of force that is exerted on the arterial walls by blood as it is pumped around the body by the heart. High blood pressure (hypertension) occurs when blood is pumping with more force than normal through arteries.
Hypertension is common, affecting around one in seven Australians. This figure increases in older Australians, who may experience an increase in blood pressure due to their arteries becoming more rigid (less elastic).
Blood pressure is very variable and can be elevated transiently by stress, emotional state, recent physical activity, smoking, caffeine and even talking. A diagnosis of hypertension is only given if a blood pressure reading from an instrument called a sphygmomanometer is higher than 140/90 mmHg after several visits to a GP. If the first figure is higher than 140, or the second figure is higher than 90, this is considered to be an indicator of high blood pressure. It is recommended that you measure your own blood pressure with an automatic blood pressure monitor first thing in the morning, while you are still in bed; blood pressure monitors can be purchased at most chemists.
Some drugs and an unhealthy lifestyle can also result in hypertension. It is important to have your blood pressure checked regularly (preferably yearly) by your GP as there are no symptoms for hypertension and it can be a risk factor in many diseases such as heart attack, kidney failure or stroke.
Lifestyle changes to improve blood pressure include increasing cardiovascular fitness by undertaking regular physical activity, cessation of smoking, a reduction in alcohol intake, and reducing fat and salt in the diet. Nevertheless, if blood pressure remains high than antihypertensive medications are required to maintain your blood pressure in a healthy range. Your GP will need to monitor your blood pressure regularly because if the dose of your antihypertensive medication is too high your blood pressure will fall, leading to dizziness and fainting on standing.
This NHMRC-funded project aims to identify areas of the brain involved in the control of blood pressure. We are currently extending an approach to studying the changes in the brain in renovascular hypertension, following patients with high blood pressure before and after renal angioplasty or stenting of the renal artery and normalisation of the high blood pressure.
A new study by Prof Rob Herbert and his team is investigating muscle contracture in children with cerebral palsy. Contracture is a stiffening of muscles, even when the muscle is passive. It is not yet known whether contracture is a result of changes in the muscle, changes in the associated tendon, or a combination of both. Around 53 per cent […]