Scientists warn that the number of  people who avoid heart attacks and strokes by taking statin therapy is much higher than the number who suffer side effects

Statins are safe and effective but their potential side effects have been exaggerated by unreliable studies, according to a major medical review.

The cholesterol-reducing tablets have been the subject of years of controversy and conflicting reports.

Millions of people take them every day but many have stopped the life-saving treatment because of fears over how safe they are.

However, a review of the available evidence on statins, published in The Lancet medical journal, has found that the risks of a negative reaction are far outweighed by the benefits.

This echoes what Robert Xuereb, chairman of the Department of Cardiology at Mater Dei Hospital, told the Times of Malta  in an interview published a  few months ago.

“In patients at a high risk of cardiovascular disease, the prevention of a heart attack, stroke and death vastly outweighs the risk of other problematic side effects. Even among lower-risk patients, preventing a major cardiovascular event is much more important than the risk,” he said.

The review argues that much weight has been placed upon unreliable evidence from observational studies, while the results from randomised drugs trials, which are reliable, have not been properly acknowledged.

The report has been released in a bid to avert an MMR-style public health scare, when there was a significant decline in the uptake of the vaccine after a report, which has since been completely discredited, linked it to autism.

In patients at a high risk of cardiovascular disease, the prevention of a heart attack, stroke and death vastly outweighs the risk of other problematic side effects

Richard Horton, editor of The Lancet, said: “We saw in a very painful way the consequences of publishing a paper which had a huge impact on the confidence in a safe and effective vaccine.

“We have learnt lessons from that episode and those lessons need to be widely propagated – they are lessons for all journals, all scientists.”

He added: “This is the first time that all of the evidence has been brought together on both safety and benefits into a single publication.

“So this is a one-stop shop of the evidence on safety and benefits of statins. There has been nowhere where you can get all of that information in a single place.”

The review found that side effects can include developing muscle pain, diabetes or a haemorrhagic stroke, but suggestions that statins cause other conditions, such as memory loss, cataracts, kidney injury, liver disease, sleep disturbance, aggression or erectile dysfunction, are not accurate.

Oxford University’s professor Rory Collins, one of the authors of the review, said misleading claims about harmful side effects was causing a “serious cost to public health”.

He added: “Our review shows that the number of people who avoid heart attacks and strokes by taking statin therapy are very much larger than the numbers who have side effects with it.

“In addition, whereas most of the side effects can be reversed with no residual effects by stopping the statin, the effects of a heart attack or stroke not being prevented are irreversible and can be devastating.”

:: What are statins?

Statins are drugs that help to lower harmful cholesterol levels in the body and help reduce the risk of cardiovascular disease, such as a heart attack or stroke.

:: How do they work?

Statins help lower the levels of harmful cholesterol in the blood and reduce how much is produced by the liver.

They are usually used in combination with lifestyle measures such as eating a healthy diet low in saturated fat, exercising regularly, stopping smoking and moderating alcohol consumption.

Cardiovascular diseases key facts

• Cardiovascular diseases (CVDs) are the number-one cause of death globally: more people die annually from CVDs than from any other cause.

• An estimated 17.5 million people died from CVDs in 2012, representing 31 per cent of all global deaths. Of these deaths, an estimated 7.4 million were due to coronary heart disease and 6.7 million were due to stroke.

• Over three-quarters of CVD deaths take place in low- and middle-income countries.

• Out of the 16 million deaths under the age of 70 due to noncommunicable diseases, 82 per cent are in low and middle income countries and 37 per cent are caused by CVDs.

• Most cardiovascular diseases can be prevented by addressing behavioural risk factors such as tobacco use, unhealthy diet and obesity, physical inactivity and harmful use of alcohol using population-wide strategies.

• People with cardiovascular disease or who are at high cardiovascular risk (due to the presence of one or more risk factors such as hypertension, diabetes, hyperlipidaemia or already established disease) need early detection and management using counselling and medicines, as appropriate.

(Source: World Health Organisation)