The world’s largest study of randomised data from statin trials recently revealed its first results, and researchers Dr Christina Reith and Dr David Preiss were on hand to answer your questions.
When might I be prescribed statins?
DP: You’ll be prescribed them if you’ve had a heart attack or stroke. In England and Wales, they are also recommended if your risk of having such an event in the next decade is more than 10% (prior to 2016 it used to be 20% and it is still 20% in Scotland). The doctor will use your QRISK3 score, which you can find online here, or in Scotland ASSIGN, found here, to work this out. It’s based on your age, cholesterol, blood pressure, ethnic origin, diabetes, family history, where you live and a host of other risk factors. You’re likely to hit its cut-off point as you approach 60 (men) or 65 (women) even if you’re healthy and don’t have high cholesterol.
What is the new study?
CR: The most robust study ever undertaken to examine the effects of statins, conducted by an international group of investigators called the Cholesterol Treatment Trialists’ Collaboration. We trawled more than 35 million records and collected data from more than 155,000 participants in large-scale, randomised, controlled trials in which neither participants nor researchers knew who was taking statins, to help resolve uncertainty and confusion about their effects.
How do statins work?
DP: By blocking an enzyme (HMG-CoA reductase) that your body uses to make cholesterol, a fatty substance produced by the liver that can build up in the arteries and increase your risk of cardiovascular disease. As a result, the liver becomes better at taking out LDL (‘bad’ cholesterol) from your bloodstream. For moderate-intensity statin therapy (which decreases LDL cholesterol by about a third), the risk of a heart attack or stroke can be reduced by about 25% each year, whereas high-intensity statins (which decrease LDL cholesterol by about half) can reduce your risk by about 45%.
‘We now know that statins are equally effective in both men and women’
How soon do statins work and do I have to up the dose as I get older?
DP: Your cholesterol should fall within a month or two. The longer you take statins, the greater the benefits. There is no need for most people to increase the dose, but different types vary in how much they lower cholesterol. High-intensity statins (higher doses of atorvastatin and rosuvastatin) cut cholesterol more than low-intensity ones (for example, pravastatin and simvastatin).
Do statins work as well for women as for men?
DP: It was previously suggested that men benefitted more but we now know they are equally effective in both sexes, an important finding given that after menopause the risk of heart disease increases in women, bringing it in line with the figure for men.
FYI - Dr Christina Reith is Senior Clinical Research Fellow and Dr David Preiss is a clinician-researcher and Associate Professor, both at Oxford Population Health, University of Oxford.
Is it true that statins can cause muscle problems?
CR: Reports that statins cause muscle pain, weakness and fatigue have caused a lot of confusion, even among doctors. But such symptoms are common with age, making it hard to pinpoint statins as the culprit. Bearing in mind that in our study people didn’t know whether they were on statins or a placebo, we found about a quarter were experiencing muscle symptoms. Further probing revealed that the difference between those people taking a statin and those taking a placebo was less than 1% overall – a huge contrast to reports indicating that statin-related muscle problems occur in around 10% or more of people on statins. What’s more, in 90% of those who have muscle symptoms and are taking a statin, it’s not due to the statin. If you do experience muscle problems due to statins, these are mostly mild and confined to the first year. Extremely rarely, about one in 10,000 people treated per year with a statin develop serious muscle problems (called myopathy or rhabdomyolysis). Symptoms can include severe muscle cramps, aches or pains, dark (tea or cola-coloured) urine, tiredness and weakness and a raised level of a blood ‘marker’ called creatine kinase.
Should I stop taking statins if I develop muscle problems?
DP: Consult your doctor, who may suggest changing the dose or trying a different statin. Ultimately, it comes down to personal choice and discussion with your doctor. If you are experiencing severe or unusual muscle symptoms, a simple creatine kinase blood test can be done to make sure you do not have the more serious but very rare condition of myopathy or rhabdomyolysis.
What about the other side-effects listed on the packet?
CR: The list of side effects – for example hair loss, nausea, constipation, headaches, joint pains, nightmares, blurred vision, depression and more – can be daunting. So far there is no high-quality evidence to support almost any of them. We will be assessing these in our study to check whether they stand up to proper scrutiny to help patients and doctors make informed decisions.
Can I reduce my cholesterol by adopting a healthy lifestyle rather than having to take statins?
CR: It is certainly important to pay attention to diet and exercise and to stop smoking. However, it’s often hard to lower cholesterol substantially by diet and exercise alone. Doctors recommend making these improvements as well as taking a statin if you need one.
What about ‘natural’ alternatives, for example red yeast rice and Coenzyme Q10?
DP: Most of these don’t stand up to scrutiny. Red yeast rice contains the chemical monacolin K, which is similar to the active ingredient in lovastatin, so if you take it, you are pretty much taking a statin, just a less effective dose. There is no evidence that Coenzyme Q10 benefits cardiovascular health.
How about plant sterols?
DP: A moderate intake (2g a day) of plant sterols, found in vegetable oils, grain products such as breads and cereals, seeds, nuts, legumes, fruits, vegetables and fortified milk products, yogurts, and yogurt drinks, can lower cholesterol slightly and won’t do any harm. Doctors recommend including plant sterols in your diet; however they are not as powerful as statins.
‘A handful of medications may require you temporarily to stop your statins’
Do any other medications interfere with statins?
DP: If prescribed, a handful of medications, including certain antibiotics such as clarithromycin and some rare oral antifungal treatments, may require you temporarily to stop your statins. If you are on warfarin, you will need more regular blood tests when starting or stopping a statin. You should also steer clear of grapefruit and grapefruit juice if you’re on simvastatin and limit yourself to an occasional glass of grapefruit juice if you’re on atorvastatin.
Should we all take a statin as we get older?
DP: There’s no right answer to this but various strategies are being examined. One idea is to offer statins based on age alone, but this is not used in the UK or anywhere else. The commonest approach – and the one used in the UK – is to calculate the 10-year risk of developing a circulatory problem. In future, doctors may calculate lifetime risk based on, for example, genetic tests and measurements such as blood pressure and cholesterol.
Find out more
SCALE OF THE STUDY 35 million records were examined. 155,000 people took part in controlled trials
CUTTING CHOLESTEROL Statins can reduce the risk of heart attack or stroke by up to 45%
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