Blood pressure is recorded as two numbers, written as a ratio, for example 140/90 mm Hg (millimeters of mercury - the blood pressure unit). The number on top is the 'systolic pressure' inside the arteries when the heart beats, and the other the 'diastolic pressure' between beats, when the heart is at rest and refilling with blood.
According to the American Heart Association, a 'normal blood pressure' is less than 120/80, and becomes high from 140/90.
‘Millions of lives could be saved by giving blood pressure-lowering drugs to people at risk of heart attack and stroke, even if they have normal pressure.’
A new study has revealed that millions of lives could be saved by giving blood pressure-lowering drugs to people at risk of heart attack and stroke, even if they have normal pressure. People at high risk include those with a history of heart or artery disease, stroke, diabetes or heart failure. Based on an analysis of 123 medical trials involving more than 600,000 people over two decades, the research team called for an urgent review of existing treatment guidelines, including those of the European Society of Hypertension which recently relaxed its recommended treatment level for high-risk patients from 130 to 140mmHg of systolic pressure.
Study lead author Kazem Rahimi of the University of Oxford said, "Our findings clearly show that treating blood pressure to a lower level than currently recommended could greatly reduce the incidence of cardiovascular disease. This could potentially save millions of lives."
The study found that every 10 mmHg reduction in systolic blood pressure reduced the risk of heart attack by about a fifth, of stroke and heart failure by about a quarter, and the risk of death from any cause by 13%.
The researchers said, "Importantly, these reductions in disease were similar across a wide range of high risk patients, irrespective of whether their blood pressure was already low (less than 130 mmHg) to begin with."
The team wrote, "Our results provide strong support for lowering blood pressure to systolic blood pressures less than 130 mmHg. High blood pressure is the leading cause of heart disease and stroke, affecting more than a billion people worldwide and killing about 9.4 million every year."