While globally stroke claims the lives of four million people a year, there is good news for the 30.9 million high blood pressure sufferers worldwide of which 3.3 million are South African. Most first strokes can be prevented by controlling high blood pressure.
A stroke occurs when blood vessels are chronically constricted and prevent the supply of sufficient nutrients and oxygen to vital organs in the body.
The greatest burden of stroke apart from death is the long-term physical and mental disability. Stroke survivors often experience physical handicap, depression and cognitive dysfunction, which affect their quality of life, productivity and survival. With few available post-stroke treatments and surgical procedures, healthcare professionals and practitioners have shifted their treatment focus to stroke prevention.
A group of leading medical experts in cardiovascular disease and hypertension from the MetaForum on Stroke Prevention in Hypertensive Patients, have identified a direct link between controlling high blood pressure, a decline in primary stroke rates and lives saved. This makes the control of high blood pressure the most important modifiable risk factor in the prevention of stroke.
Prof. Brian Rayner of the Hypertension Society and head of the Hypertension Clinic at the University of Cape Town, says that patients still do not consider high blood pressure a serious problem, despite knowledge of its consequences. “Doctors should emphasise the critical link between treatment for high blood pressure and the prevention of stroke.”
According to Prof Rayner, patients can easily assess their risk of stroke by simply asking their doctors for a routine Electro Cardiogram (ECG) test, which can promptly detect a medical condition termed Left Ventricular Hypertrophy (LVH).
“LVH is characterised by the enlargement of the left ventricle of the heart and is a key indicator for the risk of stroke. It is the result of continual narrowing of the blood vessels, typical in people with high blood pressure,” says Prof. Rayner.
Only half of high blood pressure sufferers are diagnosed and only half of those are treated. Of the latter, only half achieve adequate blood pressure control lessening the danger of stroke.
Rule of halves
This scenario was described as the “rule of halves” in 1972 by Wilber and Barrow, authors of Hypertension - a community problem. The rule of halves is still valid in most European countries and in the US, despite the development of many new medications.
Once individuals have established their risk for stroke through a non-invasive ECG test administered by the doctor, their high blood pressure can be effectively controlled and treated with anti-hypertensive agents.
It is critical that anti-hypertensive treatment commences immediately after an individual’s risk for stroke has been confirmed by his/her doctor, to ensure maximum treatment. - MSD
The Heart and Stroke Foundation South Africa