In certain circumstances, lower levels of blood pressure are also treated, for example in people with diabetes, when treatment should begin if the BP is >140/90mmHg. These recommendations are for adults up to the age of 80yrs. This is because we have little evidence on which to base treatment guidelines beyond that age, although studies in the "elderly "are underway. It is most important to appreciate that older people get substantial benefit from treating high blood pressure. If a patient is on treatment by the age of 80yrs, then treatment should continue.
Q. What levels do doctors aim to achieve - in other words how low does blood pressure need to go for optimum control?
A. The first target recommended by the British Hypertension Society is to get the blood pressure below 150/90 mmHg. The optimal level of control in a patient receiving treatment has been defined as <140/85 mmHg. Presently < 10% of people who are treated for hypertension in the UK have a blood pressure <140/90 mmHg, so there is much work to do to improve BP control in the UK.
Q. Achieving ideal levels is easier said than done in many patients. What fraction of patients end up with ideal control and how many of them require more than one drug?
A. As stated above, there is substantial room for improvement in the quality of BP control in the UK. One of the problems has been that it has often been assumed that BP can be controlled by one drug, when in fact combinations of drug treatment are invariably required. About two thirds of people with high BP will require more than one drug to get their BP controlled and 1/3 will require 3 or more drugs.
Q. Once good control is gained is it worth stopping medication for a while to see if the patient can do without it, or is treatment always lifelong?
A. For most patients, treatment is life-long. In a small number of patients with mild hypertension who require only one drug to control their blood pressure, and who have no complications from high blood pressure, a trial without treatment can be tried. It is most important that these patients are followed up long term as many of them will need to restart treatment for their BP.
Q. Do dietary and lifestyle change - such as exercise and salt restriction - make a big difference?
A. Diet changes, salt restriction and exercise can make a big difference. It is worth remembering that we treat high blood pressure to reduce the risk of cardiovascular disease. As such, these strategies will help reduce cardiovascular risk and can also lower blood pressure. In some cases this can lead to a postponement of drug therapy or a need for fewer medications.
Q. Do blood pressure readings at home mean more than those taken in the doctor's surgery?
A. The simple answer is that we don't know. All of the clinical evidence on which we base clinical decisions has been derived from doctors' office readings. It is clear however that multiple measurements of BP in the home or at work are likely to reveal a more accurate pattern of the overall blood pressure load experienced by the patient day-to-day.
Thus, in future, it is likely that home/work-place BP monitoring will become common practice. There is certainly no harm in doing this and I find such records very useful in assessing the quality of blood pressure control. For the moment, if one is to use a home monitor, it is important to use one that has been validated by the BHS if possible. A list of those which have been validated is on the BHS website.
Q. Are there any supplements or complementary approaches that patients should consider? Many seem keen to try garlic.
A. There are many claims for various supplements with regard to BP. In my view a healthy balanced diet, low in salt and with lots of fruit and vegetables, complemented by regular, sensible exercise and good control of body weight is the key to cardiovascular health. In such circumstances supplements are rarely warranted. With regard to garlic, there have been claims but few comprehensive clinical studies to substantiate the claims.
Others have tried relaxation and feel it works for them. I believe that if it works for them, then it must be good for them but not necessarily for everyone! I think we often look for simple remedies when the thought of a healthy lifestyle looks too dull and unpalatable and the supplement industry has capitalised on this.
Q. Are there any exciting developments on the horizon?
A. There are lots of exciting things on the horizon but no magical cure for high blood pressure is going to emerge. That does not mean to say we are not making progress. New drug therapies are being developed all the time and we are learning much more about how these drugs work more effectively in combination. We are learning more about the effects of high blood pressure on the brain, the heart, blood vessel walls and kidneys. New techniques for imaging the brain have provided exciting insights into the important role of high blood pressure in the development of dementia and the effectiveness of treating high BP in preventing dementia. New treatments and better use of existing treatments will invariably flow from this. The genetics revolution is also making some impact and has helped reveal the specific cause of some rarer forms of high blood pressure which has led to improvements in treatment.
I think in the short term, we need to apply what we already know, ie. that high blood pressure is an insidious, silent killer that needs more effective treatment. In the medium term, treatments will be refined and simplified and many of the different drugs used to combat cardiovascular disease will be combined in single tablets designed to lower blood pressure and cholesterol. In the longer term, I think the scientific developments today will lead to more specific targeting mechanisms of disease within the cardiovascular system to limit damage caused by high blood pressure and other risk factors such as cholesterol and diabetes.
Bryan Williams MD FRCP
Professor of Medicine
University of Leicester
We are indebited to the Blood Pressure Associationfor their help in compiling this section.
