Everyone aged 55 and over should be taking drugs to lower their blood pressure, a London-based expert says.

Epidemiology expert Professor Malcolm Law said blood pressure drugs cut the risk of heart attack and stroke even for those with normal blood pressure.

His conclusion, published in the British Medical Journal and backed by other experts, is based on a review of 147 studies, involving 464,000 people.

However, the Stroke Association warned the drugs could have side-effects.

he research found most types of blood pressure drugs cut the risk of heart attacks and heart failure by around a quarter and the risk of stroke by about a third.

The studies looked at the effect on two blood pressure measurements; systolic - the pressure when the heart beats while pumping blood - and diastolic - the pressure when the heart is at rest between beats.

The lowered risk estimates were based on lowering systolic blood pressure by 10mm Hg or diastolic blood pressure by 5mm Hg.

Widespread benefit

Professor Law, an expert in epidemiology at the Wolfson Institute at Barts and The London School of Medicine, said: "Beyond a certain age, we're saying everyone would benefit from taking drugs that lower blood pressure.

"Beyond a certain age, we all have high blood pressure and we would all benefit from lowering it.

"What we call 'normal' blood pressure is actually high, and what we call high blood pressure is actually higher."

Professor Law said the universal use of blood pressure drugs should be seen as analogous to vaccinating the entire population in the event of a flu pandemic.

There was no case for trying to assess who was a top priority, he said, when everybody was potentially at risk.

In fact, Professor Law said giving everybody blood pressure drugs would minimise the risk that people would be alarmed when told they needed to take the medication.

Among those aged 65 living in England and Wales, the risk of having a heart attack in the next 10 years is about 10% for men and 5% for women, he added.

In an accompanying editorial, Richard McManus, from the University of Birmingham, and Jonathan Mant, from the University of Cambridge, backed Professor Law's call.

They said the findings supported the idea of giving everyone over a certain age a "polypill" - a drug that would include a statin to lower cholesterol as well as treatment for blood pressure.

Professor Law is one of the pioneers of the polypill, which he says would be an effective way to cut the number of heart attacks and strokes in the UK.

Caution

Joanne Murphy, of the Stroke Association, said: "High blood pressure is the single biggest risk factor for stroke and it is important that people take medication to combat this.

"Whilst blood pressure medication is one of the safest and most studied medications, they do have side-effects and should only be prescribed to people who are at significant risk of stroke."

Mike Rich, of the Blood Pressure Association, said: "Prevention is better than cure, but there are other proven ways to prevent high blood pressure such as healthy eating and regular exercise, which have other health benefits too.

"There is a danger that these important lifestyle factors could be overlooked in favour of 'popping a pill'."