Thousands more heart attacks and strokes could be prevented in the UK if the way blood pressure drugs are dished out is changed, a study suggests.
Researchers say current prescription guidelines mean 233,000 of the killer events are prevented across the home nations every decade.
However, nearly 90,000 more could be avoided if doctors gave the drugs to patients based on a similar method as to how statins are dished out.
Experts have called on health chiefs to reassess the guidelines on dishing out the life-saving drugs, ahead of new advice for GPs expected next month.
Hundreds of thousands more people are to be offered blood pressure drugs on the NHS to curb the number of heart attacks and strokes, according to a draft plan published in March.
Researchers say current prescription guidelines mean 233,000 of the killer disease events are prevented across the home nations every decade. However, nearly 90,000 more could be avoided if doctors gave the drugs to patients based on a similar method as to how statins are dished out
The move – which is the biggest change to blood pressure guidance in nearly a decade – means 720,000 people will become eligible for daily pills.
But the research found giving patients the pills based on their 10-year risk of developing cardiovascular disease, not the proposed guidelines, would prevent even more heart attacks and strokes.
Dr Emily Herrett, lead author at the London School of Hygiene and Tropical Medicine, said: ‘Our findings suggest that there is a need to reassess current treatment guidelines.
‘A strategy of treating blood pressure based on overall cardiovascular risk prevented the most heart attacks and strokes, and minimised the proportion of people treated without benefit.’
She added: ‘Blood pressure is just one component of absolute cardiovascular risk. The current strategy treats only people with high blood pressure.
‘But that means many people who might benefit from blood pressure lowering treatment are missing out, whereas others might be treated unnecessarily.’
Dr Herrett added drugs ‘are not a silver bullet’, saying doctors should always encourage patients to overhaul their lifestyles to curb their blood pressure.
The researchers analysed data from the UK general practice of 1.2million patients, aged 30 to 79, who did not have cardiovascular disease.
The study, published in prestigious medical journal The Lancet, assessed and compared four possible strategies for blood pressure treatment.
These included the currently recommended guidelines from Nice, as well as the proposed guidelines it is expected to announce next month.
The guidance relates to people with ‘stage one hypertension’ – those with a blood pressure reading above 140/90 but below 160/100.
ARE HEALTHY DIETS OR MEDICATION MORE EFFECTIVE AT LOWERING BLOOD PRESSURE?
Low-salt diets packed with fruit and vegetables lower blood pressure more than medication after just four weeks, a Harvard University study suggested in November 2017.
Cutting out salt and eating lots of fruit, vegetables and low-fat dairy, reduces people with high blood pressure’s results by an average of 21 mm Hg, the research adds.
To put that into context, the Food and Drug Administration (FDA), the US’ drug-approving body, will not accept anti-hypertension medications unless they lower blood pressure by at least 3-4 mm Hg.
Most medications typically reduce hypertension readings by between 10 and 15 mm Hg, but come with side effects including fatigue, dizziness and headache.
Study author Dr Lawrence Appel said: ‘What we’re observing from the combined dietary intervention is a reduction in systolic blood pressure as high as, if not greater than, that achieved with prescription drugs.
‘It’s an important message to patients that they can get a lot of mileage out of adhering to a healthy and low-sodium diet.’
Around 32 percent of adults in the US, and one in four in the UK, have high blood pressure, which puts them at risk of heart disease and stroke.
The researchers analyzed 412 people with early-stage hypertension who were not taking high blood pressure medication.
Some of the study’s participants were fed a ‘DASH (Dietary Approaches to Stop Hypertension) diet’, which includes lots of fruit, vegetables and low-fat dairy products, with minimal saturated fat.
The remaining participants ate a typical American diet.
All of the participants were fed different sodium levels equaling around 0.5, one or two teaspoons of salt a day over four weeks with five-day breaks in between.
Previously people in this group would only be eligible for pills if they also were judged to have a 20 per cent chance of also developing heart disease in the next decade.
The new guidance lowers this threshold to those with a 10 per cent risk of developing heart disease in the next decade – an extra 450,000 men and 270,000 women.
It is expected to push the number of eligible adults in Britain with ‘stage one’ blood pressure up from 290,000 to more than 1million.
The other two strategies analysed were just using blood pressure scores or a patient’s predicted 10-year risk of developing CVD.
The proportion of patients eligible for treatment and the number of CVD events that could be prevented with treatment was estimated for each strategy.
Researchers also estimated eligibility and the number of CVD events that would occur during 10 years in the UK general population.
Under current Nice guidelines, the team found 6.5million people would be eligible for treatment and 233,152 CVD events could be avoided if all were treated for 10 years.
If treatment was based on blood pressure alone, 11.6million people would be eligible for treatment, with 301,523 CVD events avoided.
Proposed Nice guidelines for 2019, expected to be published next month, would lead to treatment eligibility for 7.9million people and 270,233 events could be avoided.
However, the study funded by National Institute for Health Research, suggested the most successful strategy was treating blood pressure based on a patient’s overall 10 year CVD risk.
This would qualify 8.6million patients for treatment, but could avoid the 322,921 CVD events – 38.5 per cent more than the existing Nice guidelines.
Leading GPs have warned the Nice move will mean people will be given drugs they do not need – and should instead be advised to diet and exercise.
However, cardiologists said when the draft guidelines were announced in March that the threshold had not been lowered far enough, leaving millions still at risk.
US officials lowered the treatment threshold in 2017 from patients needing a blood pressure score of 140 to 130, making an estimated 70million Americans eligible.
The European Society of Cardiology last summer also lowered its thresholds, saying drugs should be dished out if lifestyle changes fail to control blood pressure levels.
Experts have welcomed the research. Professor Naveed Sattar, of the University of Glasgow, said it challenges long held beliefs with regards to blood pressure.
He added ‘it makes sense’ for overall risk for heart disease to dictate when doctors recommend drugs to combat high blood pressure.
‘Guideline committees should give this new paper detailed consideration as they weigh up future recommendations,’ Professor Sattar added.
Roughly 13.5 million people in England have high blood pressure, and about 8million are currently eligible to take the cheap drugs.
High blood pressure is considered to be 140/90 or higher, except for those over the age of 80 where anything over 150 is deemed unhealthy.
Hypertension is known to increase the risk of heart attacks and strokes, of which there are 1.5million in the UK every year.
WHAT DOES IT MEAN IF I HAVE 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