What exactly are statins, asks Claire O'Connell
Statins are a class of drugs that can lower cholesterol levels. By blocking an enzyme in the liver that the body uses to make cholesterol they can reduce the amount of LDL or "bad" cholesterol in the blood, and they may also act as anti-inflammatory agents.
Statins - which vary in their potency between brands - can reduce the risk of heart attack by up to 60 per cent and the risk of stroke by up to 17 per cent, and rank among the most commonly prescribed medications in the world.
SHOULD CHOLESTEROL-BUSTING drugs be put in the water supply to help prevent heart disease?
The half-in-jest question arose yet again following a major international study that found a brand of statin reduced the risk of heart attack and stroke in "apparently healthy" people.
Statins are among the most prescribed drugs in the world and are frequently given to people with high cholesterol levels. But the new study, published last week, found that the statin Crestor could also benefit a certain group of people who had normal cholesterol levels.
"The new statin drug that cuts the risk of heart attacks and strokes for everyone," proclaimed a headline in the Daily Mail in Britain, while the BBC went with a more sober "Statin use 'may benefit healthy'." Meanwhile, analysts reckoned the research would boost statin prescriptions across the board in a market already worth more than €25 billion.
But delve behind the headlines, and statins may not be for everyone after all.
The Harvard-led and drug-company-funded study Jupiter, published in the New England Journal of Medicine, trialled Crestor in almost 18,000 people across several countries who had normal cholesterol levels and who would not normally be prescribed the drug.
For those people, taking the medication almost halved the relative risk of developing a heart attack, and the researchers even stopped the trial early because the results were so convincing.
But crucially, the "apparently healthy" subjects all showed signs of inflammation before they started on the medication, testing positive for a marker in the blood called high-sensitivity C-reactive protein (hsCRP), which is a sign of inflammation and could be a signal of future heart trouble.
Jupiter's findings could now encourage wider testing for hsCRP and new guidelines on whether patients with high levels of the marker should be prescribed statins as a preventative measure.
The research has won warm welcome from consultant cardiologist Prof Mahendra Varma, who chairs the Northern Ireland Chest, Heart and Stroke Association. "I have long been advocating the use of statins on a large and wide basis," Varma said when news of Jupiter's results broke.
Yet not all heart experts are so keen on statins for all. "I think the bottom line on this study should be of cautious welcome," says Dr Brian Maurer, consultant cardiologist and medical director of the Irish Heart Foundation. " is a very interesting observation, but what the implications are for overall treatment and prescribing remains to be evaluated."
Doctors tend not to routinely test for hsCRP, but this study could encourage more to do so, notes Maurer. "I think what it tells practising physicians they should be doing is measuring CRP."
And he refers to the study's funders, AstraZeneca, which manufactures Crestor and stands to gain from the results: "I wouldn't go so far as to say that it shows drug company bias, but the drug company is obviously playing it for all it's worth.''
While statins are useful, Maurer says he would be cautious about prescribing them universally. One issue is the potential side effects: "While major side effects are rare, minor side effects are relatively common, like muscle pains and aches, insomnia and just low-grade not feeling terribly well,'' he says.
The other problem with everybody taking statins, according to Maurer, is that you end up treating a large number of people who are not going to benefit to hit a small number who will.
"There is a serious danger when one talks about putting people on drugs for primary prevention, that we would be treating too many people for the benefit that we would produce in a minority," he says.
However, Jupiter is not the first study to show the benefits of statins in people who have normal cholesterol profiles but a high risk of heart attack or stroke, and they should be used where the benefits outweigh the risks of side effects, according to clinical pharmacologist Prof Alice Stanton from the Royal College of Surgeons in Ireland.
"Jupiter confirms what we would have expected, and statins should be given to anyone at moderate to high risk of cardiovascular events," she says.
"Statins at a moderate dose will give you a 30 per cent reduction in heart attacks and strokes no matter who you give it to. If you are at low risk then the risk of side effects approach the benefits that you get by a reduction of heart attacks and strokes," she says.
"But if you are at moderate to high risk of heart attacks and strokes, your risk of adverse events stays the same, and the benefit that you get in protection is considerably greater than the adverse events."
Already doctors are prescribing statins more frequently than aspirin for patients at risk of heart attack and stroke, according to Stanton, but she believes the medications should not be available without advice from doctors, nurses or pharmacists.
"I don't think individuals are sufficiently knowledgable to prescribe for themselves. I think it needs a medical knowledge to make that decision at what level of risk one should be taking either aspirin or statins," she says.
"The side effect profile of statins for the majority of people is exceedingly good, and 95 per cent of people tolerate them very well.
"But you do have to look for muscle and liver problems and that's partly why we say at the moment you still have to remain in medical hands."