A third more heart attacks and strokes could be prevented in the UK if the way blood pressure drugs are prescribed is changed, a new study suggests.
The research estimates treatment based on a patient’s overall cardiovascular risk could prevent an additional 85,000 cardiovascular disease (CVD) events over 10 years, compared to current recommendations.
People with high blood pressure or other cardiovascular risk factors are at increased risk of experiencing cardiovascular events, such as heart attacks and strokes.
There are nearly 1.5 million such CVD events in the UK each year.
Led by the London School of Hygiene & Tropical Medicine (LSHTM), the researchers used anonymised records from UK general practice of 1.2 million patients, aged 30 to 79, without CVD.
Dr Emily Herrett, lead author and assistant professor at LSHTM, said: “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.
“Under any blood pressure lowering strategy, when a patient is identified as eligible for treatment, the first steps should always explore whether lifestyle changes could reduce blood pressure or risk.
“It’s important to remember that drugs are not a silver bullet.
“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.”
The study published in The Lancet assessed and compared four possible strategies for blood pressure treatment.
These were the currently recommended 2011 National Institute for Health and Care Excellence (Nice) guidelines, proposed 2019 Nice guidelines, using blood pressure alone and using predicted 10 year CVD risk alone.
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 6.5 million 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, 11.6 million people would be eligible for treatment, with 301,523 CVD events avoided.
Proposed Nice guidelines for 2019, which are expected to be published next month, would lead to treatment eligibility for 7.9 million 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, say the researchers, would qualify 8.6 million patients for treatment, but could avoid the 322,921 CVD events.
The team acknowledge limitations of the study, including that they have not yet investigated the potential harms of a change in blood pressure treatment eligibility.
In addition, the research has assumed the treatment benefit from blood pressure lowering drugs is achieved across the blood pressure spectrum, where there is currently some conflicting evidence.