Statins help reduce the death rate in people with a history of heart disease by as much as 20%. Now, doctors are starting to widen the net of people they could help.
By HELEN SIGNY
Statins work by raising the level of "good" HDL (high-density lipoprotein) cholesterol in the blood and lowering the level of "bad" LDL (low-density lipoprotein). LDL is responsible for plaque that builds up on artery walls and causes heart attacks and strokes. Statins also help reduce other damaging materials that are made along with cholesterol, explains Dr David Sullivan, clinical associate professor at the Royal Prince Alfred Hospital in Sydney, Australia.
Statins first appeared in South Africa in 1990, with the release of simvastatin (Zocor). Then, in 2002,less-expensive generic versions were introduced, making the drug readily available. According to Dr Dirk Blom of the Division of Lipidology at the Health Sciences Faculty at the University of Cape Town, this was a very welcome development. “Today statins cost a quarter of the price they did ten years ago,” he says. “This has been a very positive thing – we are treating many more people and a major impression has been made.” Current estimates of the number of South Africans on statin medication range from at least 380,000 to perhaps a million or more.
In 2003, pharmaceutical company AstraZeneca launched a large-scale,five-year international clinical study into the effectiveness of statins in the general population aged 50 or over. South Africa was among the four countries selected to participate in the trial, with 2,497 patients taking part. Findings of the JUPITER trial, as it became known, were presented at last year's American Heart Association convention.
Looking beyond patients who are known to benefit, it found that for people with low cholesterol, but high levels of a protein in their blood called C-reactive protein (CRP), the risk of having a heart attack or stroke, or needing angioplasty or bypass surgery, was more than halved if they were given a statin. So convincing were the findings that the study was abandoned after just two years.
The implications of the JUPITER findings are huge. In the US, if everyone with high levels of CRP was given statins, 80% of Americans would be eligible. The US Academy of Paediatrics has recommended statins be considered for children as young as eight if they have high cholesterol.
In the UK, GPs are being encouraged to prescribe statins to any patients aged between 40 and 74 who have a risk greater than 20% of having a heart attack. This means the numbers on statins there could double to seven million.
"The JUPITER Trial has set the cat among the pigeons," says Blom. "South Africa has not decided how it will respond, because there is still an issue of cost." That will be left to the respective provincial government policymakers. Still, many heart doctors and GPs would like to see even more of us taking statins.
According to the Heart and Stroke Foundation of South Africa, 80% of westernised South Africans have raised blood cholesterol, and 20% of this group have levels placing them at high risk of developing CVD.
"South Africa lacks a nationwide policy that is implemented uniformerly for treating cholesterol using statin therapy so treatment is very uneven," explains Blom. "Some are treated very well, while others are not. It all boils down to what you can afford and what you have access to geographically. In the public system, most patients will get statins if they need them," he says.
"But the level of dose will not always be as high as in the private system, where people can afford the more expensive high-dose statins – but any lowering of cholesterol is a good thing."
So should you be on statins? Here's what you should know:
The benefits can't be matched
One thing is clear: taking statins makes a difference to our rates of heart attack and stroke. When people prescribed with statins stop taking the drug, the effect is profound – their cholesterol once again begins to climb, says Dr Andrea Mant, associate professor in the School of Public Health and Community Medicine at the University of NSW. Substituting the drug with exercise and better diet does not achieve the sharp decline in Cholesterol that statins can achieve.
Dr David Sullivan points out that,at best, you could lower your cholesterol by 30% by reforming your diet and exercise. Most patients manage 5% to 10%, and that's rarely sustained. By comparison, statins can often lower cholesterol levels by up to 50%, depending on the statin used, dosage and patient response.
Cardiologists say nobody in today's society has cholesterol as low as it was designed to be; in comparison to huntergatherer communities, our collective cholesterol level is through the roof.
In 20 years of monitoring, statins have been proven to be safe and cost-effective. The risk of major problems from taking a statin is less than that from taking aspirin. In trials where some people have been given a statin and others a sugar pill, lots of those on the placebo developed the same sorts of side effects, too.
"Any person who meets the inclusion criteria of the statin trials should not be anxious about taking a statin," says Hamilton-Craig. But, he adds, patients need to be "monitored regularly for adverse effects, and remain under regular medical supervision".
A magic little pill
South African specialists prescribe statins for people at high risk of having a cardiovascular episode – this means people who have already had a heart attack, stroke, heart bypass or angina, and those who have high blood pressure, high cholesterol levels or diabetes.
But one day they may routinely be given to everyone over a certain age in the form of a “polypill”, one pill containing a combination of drugs designed to reduce the risk of heart disease.
Last year, worldwide trials were launched of a "polypill" combining a statin, blood-pressure-lowering medication and aspirin. The trials are determining whether people who are otherwise healthy but have risk factors for heart disease would benefit from it. Already, the polypill, which costs as little as R260 for a year's course, is showing promise in developing countries, where it could provide cheap, easy-to-use prevention on a mass scale.
"The results of the first polypill were presented in March and it was estimated that cardiovascular mortality would be reduced by about 48% in an Indian population aged over 45 years who had 'average' risk factors over a five-year period," says Ian Hamilton-Craig, a professor of preventive cardiology and internal medicine.
There are in fact very few people who do not have risk factors by the age of 45.
Studies are also now underway to investigate whether statins could help prevent or slow the progression of Alzheimer's disease, colon cancer and even melanomas.
South Africa's most common statins
- Atorvastatin (Lipitor)
- Cerivastatin (Baycol)
- Fluvastatin (Lescol)
- Pravastatin (Prava)
- Simvastatin (Zocor)
There's always a downside
Up to 15% of people on statins experience side effects – it's one of the reasons so many people stop. The most common are headaches, stomach problems such as constipation and diarrhoea, rashes, weakness and muscle pain. There's also concern that they may make people forgetful and affect mood. And in rare cases they can cause liver failure or permanent muscle damage, known as rhabdomyolysis.
The first comprehensive paper on statins' adverse side effects, published by the University of California earlier this year, found much greater levels of muscle problems, cognitive issues and numbness in the fingers and toes than doctors expected. Other common gripes included blood glucose elevation and tendon problems – with higher-dose statins more likely to cause side effects.
One theory is that statins stop the body's energy-producing cells, the mitochondria. These cells produce energy with the use of an enzyme called coenzyme Q10.
Statins block the production of this enzyme, meaning the body has less energy and more free radicals are produced as a result.
Cardiologists say that the side effects of statins are negligible – so long as your doctor is watching you for anything serious – and the benefits far outweigh the odd ache and pain. But some GPs aren't so sure, claiming they see patients with muscle aches, dyspepsia and fatigue that could well be related to their statin.
Statins can also interact with other medications, especially other cholesterol-lowering drugs, antibiotics, some antidepressants and immunosuppressants, while grapefruit juice contains a chemical that makes statins more potent.
There's also the question of whether the benefits of statins have been overstated. For example, studies have shown that lowering cholesterol in women doesn't confer the same overall benefit as it does in men. Also, for the over-75s the benefits of statins don't exceed the risks, even in people with heart disease.
Associate Professor Peter Dingle, an environmental and nutritional toxicologist at Murdoch University in Perth, Western Australia, believes statins do reduce the risk of a heart attack, but they don't bring down overall mortality. There's even some evidence that lowering cholesterol can increase the risk of cancer.
"Those who do not die of a heart attack now die of something else, most commonly cancer," he says. "The mortality rate stays the same if you’re on the drugs or not."
How to alleviate the side effects of statins
If you're prescribed statins, chances are you'll be taking them for life: stop them and in a couple of weeks your cholesterol level will go back up again.
See your doctor if you're one of the unlucky ones who experiences uncomfortable side effects. Talk to him or her about other solutions, such as:
- switching to a different statin or lowering the dose;
- taking a short break from the medication to see if that's really the cause of your discomfort – it could just be old age;
- changing to other cholesterol lowering medications;
- trying a coenzyme Q10 supplement;
- altering your exercise regime.
Source: Mayo Clinic
[This is a revised extract of an article that originally appeared Reader's Digest. The current edition is on sale now.]