LONDON – - The benefits of statins - cholesterol-busting drugs that can dramatically reduce the risk of heart attacks and strokes - have been underestimated and their harms exaggerated, scientists said on Thursday in a major review of research.
In an effort to counter what they said were misleading reports of high levels of side effects, the scientists said in the Lancet medical journal there was a "serious cost to public health" in such claims, which can dissuade people from taking beneficial medicines.
"Our review shows that the numbers of people who avoid heart attacks and strokes by taking statin therapy are very much larger than the numbers who have side effects," said Rory Collins, a professor at the Clinical Trial Service Unit at Britain's Oxford University.
He also said that those who experience side effects -- which include muscle pain, nausea and liver problems -- could reverse them by stopping the statin, while the effects of a heart attack or stroke "are irreversible and can be devastating".
Once among the biggest revenue generators for drugmakers such as Pfizer and AstraZeneca, most statins are now off-patent and available as cheap generics.
U.S. health guidelines recommend aggressive statin therapy for high-risk patients. In Britain, they are taken by an estimated 7 million people and health authorities have said they should be prescribed more widely as preventatives.
Cardiovascular diseases such as heart attacks and strokes are the world's number one killers, accounting for an estimated 31 percent of all deaths and claiming 17.5 million lives a year worldwide, according to the World Health Organization.
A row over statins erupted in Britain in 2013 when the British Medical Journal published papers by Harvard Medical School's John Abramson and UK cardiologist Aseem Malhotra claiming up to 20 percent of users get side effects.
The 20 percent figure was later retracted after the BMJ said it was based on flawed data, but this and other reports affected patient confidence.
In their review, Collins' team found that periods of intense public discussion about statins were followed by rises in the proportion of people who stop taking the drugs, and by falls in the number of prescriptions for them.
As well as in Britain, studies in Denmark, Australia, Turkey and France have suggested that media debate about side effects of statins has led to measurable effects on their use.
David Webb, president of the British Pharmacological Society, said he feared many patients who should take statins had been persuaded against them by exaggerated claims of harm:
"It is likely that many lives have been lost based on a received view that statins are dangerous and ineffective," he said.
The review found that lowering cholesterol by 2 millimoles per liter with a statin, such as a daily 40 milligram tablet of atorvastatin for 5 years in 10,000 patients would prevent major cardiovascular events in 1,500 people and cause problematic side effects in around 200.