Millions of healthy people should be prescribed blood pressure lowering medication because the pills can prevent heart attacks later in life, a major study has claimed.
In the biggest study of its kind, Oxford University researchers found lowering levels even from a healthy starting point slashed the risk of heart disease and strokes years down the line.
Currently, treatment is only given to people with extremely high blood pressure, known medically as hypertension. It means about a million Britons are prescribed the cheap pills – which cost between 28p and £1 a day – every year.
Oxford scientists claimed this threshold prevents millions of people who could benefit from the drugs from accessing them and are now calling for a complete overhaul to the way they are prescribed.
Doctors should look at a person’s overall risk of heart disease, including weight, exercise levels and family medical history – instead of solely relying on blood pressure levels, they say.
Cholesterol-lowering drugs known as statins are already prescribed in this way and anyone with a 10 per cent chance of future heart troubles is encouraged to take them.
If the same approach was used for blood pressure drugs then 12million more people would become eligible for prescriptions.
Millions of healthy people should be prescribed blood pressure medication because the pills can prevent heart attacks later in life, scientists say (stock image)
Blood pressure is measured in millimetres of mercury (mmHg) and is given as two figures – systolic pressure, the pressure when your heart pushes blood out, and diastolic pressure, the pressure when your heart rests between beats.
As a general guide, ideal blood pressure is considered to be between 90/60mmHg and 120/80mmHg.
Currently people in the UK are considered to have hypertension if their blood pressure is above 140/90.
They are then prescribed drugs such as beta blockers, which reduce stress on the heart, or ACE inhibitors and angiotensin II receptor blockers, which relax blood vessels.
But the latest study, which looked at data from 350,000 people, found heart disease could be prevented if blood pressure was reduced from much lower levels.
Presenting the findings at the European Society of Cardiology congress, study leader Kazem Rahimi, associate professor of cardiovascular medicine at Oxford, said: ‘Greater drops in blood pressure with medication lead to greater reductions in the risk of heart attacks and strokes.
WHAT IS HIGH BLOOD PRESSURE?
High blood pressure, or hypertension, rarely has noticeable symptoms. But if untreated, it increases your risk of serious problems such as heart attacks and strokes.
More than one in four adults in the UK have high blood pressure, although many won’t realise it.
The only way to find out if your blood pressure is high is to have your blood pressure checked.
Blood pressure is recorded with two numbers. The systolic pressure (higher number) is the force at which your heart pumps blood around your body.
The diastolic pressure (lower number) is the resistance to the blood flow in the blood vessels. They’re both measured in millimetres of mercury (mmHg).
As a general guide:
- high blood pressure is considered to be 140/90mmHg or higher
- ideal blood pressure is considered to be between 90/60mmHg and 120/80mmHg
- low blood pressure is considered to be 90/60mmHg or lower
- A blood pressure reading between 120/80mmHg and 140/90mmHg could mean you’re at risk of developing high blood pressure if you don’t take steps to keep your blood pressure under control.
If your blood pressure is too high, it puts extra strain on your blood vessels, heart and other organs, such as the brain, kidneys and eyes.
Persistent high blood pressure can increase your risk of a number of serious and potentially life-threatening conditions, such as:
- heart disease
- heart attacks
- heart failure
- peripheral arterial disease
- aortic aneurysms
- kidney disease
- vascular dementia
‘This holds true regardless of the starting blood pressure level, in people who previously had a heart attack or stroke, and in people who have never had heart disease.’
Professor Rahimi and his team found the chance of a heart attack in the next four years could be slashed by seven per cent for every five-unit reduction in systolic blood pressure.
The risk of a stroke plummeted by 13 per cent in the same time period and the chance of dying from cardiovascular causes dropped five per cent.
The reduced risk remained consistent no matter what a person’s blood pressure was to start with.
It means even people who have a systolic blood pressure of 120, at the upper-end of the healthy range, would be less likely to die from heart conditions if their levels were brought down to 115.
But blood pressure drugs can cause a slew of side effects, including anxiety, drowsiness, coughs, diarrhea or constipation, dizziness, headaches and vomiting.
Professor Rahimi said these need to be weighed up when prescribing the pills to patients with a very low risk of suffering heart troubles.
Healthy people with a one per cent chance of suffering a heart attack should not be given them, he stressed. But smokers or diabetics with a one in 10 chance should.
He added: ‘The decision will depend on an individual’s likelihood of suffering cardiovascular disease in the future – there are a number of risk calculators health professionals can use.’
Around 13million people in the UK have high blood pressure, and the British Heart Foundation said a further five million may have it without knowing.
Left untreated the condition can physically damage the arteries, heart and brain, and lead to heart attacks, heart failure, dementia, kidney failure or stroke.
Professor Sir Nilesh Samani, medical director at the British Heart Foundation, which funded the research, said: ‘This study again emphasises the importance of controlling blood pressure as well as possible, to reduce the risk of heart and circulatory diseases.
‘The benefits of lowering blood pressure are there whether you have pre-existing heart disease or not and lowering blood pressure – even if it is in the normal range – is associated with fewer heart attacks and strokes.
‘This doesn’t mean we should treat everyone with blood pressure lowering drugs. If someone already has a low risk of heart disease, a 10 per cent reduction in their blood pressure may only carry a small direct benefit.
‘Ultimately, the decision to treat blood pressure and the target level to aim for is something that requires a conversation between the patient and the doctor.
‘It’s also important to remember that blood pressure can be improved by means other than medication such as exercise and losing weight.’
Mass medication could prove difficult because many of those prescribed tablets for high blood pressure don’t take them because they don’t feel ill enough, while persuading healthy people to take a pill for life could prove even trickier.
There are also worries that over-reliance on pills would lead to people neglecting other aspects of their health, such as diet and exercise.
The policy would also be controversial because it would suggest millions of people who were previously considered to be healthy were now at risk of heart attacks.
Health bosses were accused of ‘over-medicalising’ middle-aged people in 2014 when a similar rule change lowered the threshold for statins.