A study claims that although cholesterol-lowering drug Statin can radically cut the risk of heart attacks, for healthy people the risks outweigh the benefits. Tom Clarke reports on the controversy.
Please wait while this video loads. If it doesn't load after a few seconds you may need to have Adobe Flash installed.
A review of the best publically available data on statin drugs was bound to cause controversy. Statins are one of the most commercially successful drugs ever manufactured – earning £22bn last year for big pharmaceutical companies.
They are not successful for nothing. If you have had a heart attack, or are at serious of having one in future, statins have been shown, without question, to help you live longer.
They work by lowering the levels of "bad" cholesterol in the body. It is this cholesterol that builds up in arteries and leads to an increased risk of heart disease and stroke.
The guidelines on statins drawn up by the National Centre for Health and Clinical Excellence (NICE) say the drugs should be given to anyone who has had a heart episode or carries a 20 per cent increased risk of having a heart attack in the next 10 years (this based on a GP's assessment of heart attack risk factors).
Because of their success and their apparently benign safety profile many GPs chose to prescribe statins more widely. For example a patient may be put on a statin just because they have high cholesterol, but not other risk factors for heart disease.
Some eminent doctors and academics recommend NICE guidelines are too restrictive. They argue the potential protective effect of statins means they should be far more widely used. Some go so far as to say that everyone over 50 should be put on the drugs to reduce their risk of heart disease in future.
The Cochrane Group reviewed the 14 major clinical trials of more than 34,000 patients on statins to look at the evidence for their effectiveness. They found the drugs are good at reducing the danger of heart disease in people who already have it. However they didn't find evidence for statins preventing a heart attack for people who haven't had one already.
The studies suggested that statins given to people at low risk of heart disease reduce the risk of a heart attack in a year from nine in 1,000 to eight in 1,000. Their conclusion was not that the evidence showed statins didn't work at preventing a heart attack, but that there wasn't good evidence to show that they do.
Because statins can have some harmful side-effects, they recommend that doctors should be cautious in prescribing them to people with a low risk of having a heart attack.
For and against
They also noted that 13 of the 14 trials in the study were sponsored by the drug companies that make statins.
"We know industry-sponsored trials are more likely to report favourable results for drugs versus placebo, so we have to be cautious about interpreting these results," said Cochrane researcher Dr Fiona Taylor.
Professor Sir Nicholas Wald, of Queen Mary University London, inventor of the "polypill" a combination of heart-protecting drugs which includes statins thinks the Cochrane team have got it wrong.
"This study is completely unsatisfactory," he said. "Their conclusions aren't justified by the data they present and are at variance with other studies which show the benefit of statins in lowering heart disease risk."
Professor Wald points out because statins can take many months to start to lower cholesterol there are good clinical reasons for starting people on the medicines before they develop the classical risk factors for heart disease.