More doubt cast on benefit of beta blockers for high blood pressure

A comprehensive study has produced more evidence that a drug widely used to treat high blood pressure may not be the best option for many patients.

According to a Swedish research team who analysed data on more than 105,000 people, they found beta blockers were not as effective as other drugs in reducing high blood pressure.

The findings echo a high profile international study last month which found modern drugs were more effective.

At present beta blockers are used to treat more than two million people in the UK alone, but current thinking suggests they should not remain as first choice in the treatment of primary hypertension.

According to experts, across the world, more than a quarter of the adult population, as many as one billion people, have high blood pressure.

In the study the researchers, from Umea University Hospital, first challenged the effectiveness of beta blockers last year in a preliminary study.

They found that one of the drugs, atenolol, was less effective than other drugs at reducing the risk of heart and circulation problems in patients with high blood pressure.

The same team has now examined the results of 13 trials, and have found that the risk of stroke was 16% higher with beta blockers than with other drugs, and the overall chance of dying was 3% higher.

However when the team looked at atenolol separately, the risk of stroke was 26% higher than for other drugs.

In a separate analysis it was seen that beta blockers cut the risk of a stroke by just 19% compared to having no treatment at all, which was about half the expected effect.

Lead researcher Professor Lars Hjalmar Lindholm says that switching hypertension treatment from beta blockers to other low-cost antihypertensive drugs in patients without heart disease should have a major health effect without increasing the cost.

He does caution however, that such a change, should be carried out slowly and under a doctor's supervision.

He says when compared with other antihypertensive drugs, the effect of beta blockers is clearly 'suboptimum' and carries a higher risk of stroke.

The team believe that beta blockers should not remain as first choice in the treatment of primary hypertension.

In September the full results from the ASCOT study found that beta blockers were out-performed by newer drugs such as calcium channel blockers and ACE inhibitors.

The NHS drug watchdog, the National Institute for Health and Clinical Excellence (NICE), has said it will consider its advice on blood pressure lowering drugs in light of recent data.

However Alison Shaw, of the British Heart Foundation, said beta blockers had a wide range of benefits for patients besides lowering blood pressure.

She says there is strong evidence that beta-blockers help to prevent angina attacks and reduce heart attack risk for people with coronary heart disease, and patients taking beta-blockers should not consider stopping or changing their medications on the basis of this study.