June 2, 2014, by James Smith
Statins: The Thatcher of Drugs
7 Million people in the UK currently take a Statin, with the NHS claiming that they save an estimated 7,000 lives per year. On paper, they may look like a wonder drug. Indeed, the National Institute for Health and Care Excellence (NICE) recommend them as primary prevention for cardiovascular disease (CVD) in adults with a 20% risk of developing it in 10 years. But despite this apparent success and evidence in support, Statins have been a class of drug that have oozed controversy throughout their 27 years on the market.
Statins work by inhibiting HMG-CoA Reductase, an enzyme found in the Liver, and is responsible for around 70% of total cholesterol synthesis in our bodies. A theory, called the lipid hypothesis, states that by lowering cholesterol, the risk of coronory heart disease is decreased. With heart attacks and strokes being a huge killer in the UK, reducing an individual’s risk of these is imperative and statins apparently offer this.
One point of controversy stems from dispute over the validity of the lipid hypothesis, with a group of scientists (admittedly a minority) claiming that the lipid hypothesis is null. If an increase in cholesterol doesn’t increase the risk of coronary heart disease; decreasing cholesterol via use of statins will not produce a reduced risk in coronary heart disease. A network of academics, known as The International Network of Cholesterol Skeptics (THINCS), have dedicated themselves to proving the lipid hypothesis is false, claiming that ‘the scientific evidence in support of the cholesterol campaign is non-existent’. Despite this rebellious group, there is much evidence weighted towards the lipid hypothesis and statins being therapeutically beneficial. The Scandanavian simvastatin survival study provides one such piece of evidence; showing a statin (simvastatin) successfully reducing mortality and morbidity in subjects by 30%. Numerous other studies and trials show efficacy of statins and support the lipid hypothesis theory, therefore this controversy championed by THINCS may ironically be treated with some skepticism.
Some of the reported side effects of statins are the main factors of controversy and certainly create some cause for concern. One such side effect is rhabdomyolysis. This mouthful of a word means ‘stripping of muscle’ in greek, summing up effectively what happens. The skeletal muscles rapidly breaks down leading to a large amount of muscle cell debris entering the blood stream. This can lead to kidney failure, as some of the waste products and proteins can harm and block the kidneys from functioning, which can lead to death in severe cases. Although this effect only occurs in 0.44 per 10,000 people (Santhasivan and Vecky 2008), it is alarming that a class of drug that is on the market and widely prescribed can precipitate a condition with a 20% mortality rate. Perhaps more shockingly, there is an increased risk of 9% for the development of Type II Diabetes Mellitus associated with statin use (Sattar N et al 2010). Diabetes can increase CVD risks, paradoxical to the desired effect of statin treatment, as well as introduce new issues such as kindey impairment and neuropathy. There have also been concerns raised about the relationship between statins and cancer, but there is no such evidence suggesting an associated increased risk as of yet.
All drugs can have adverse effects. The reality is that before any drug treatment is started, the therapeutic benefit needs to be balanced with the associated risks, for each individual patient, before a suitable treatment regimen is created. For those patients at a 20% risk of CVD, the benefits of statins nearly always outweighs the risk. Despite this, the controversies and doubts are amplified by the media and often lead to patients refusing or maintaining poor compliance with statins. The consideration to prescribe low doses of statins to patients at a lower risk of CVD, for example in all males over 40 years old regardless of health and lifestyle, has also sparked controversy within the NHS. Those patients will receive less benefit but the same risk and arguably may introduce more risk than benefit. Putting this in perspective, a 41 year old man who is at a healthy weight, does not smoke and exercises regularly (like Ryan Giggs) is at a very low risk to develop CVD or diabetes, with the only real factor against him being his age. Therefore, taking a statin may be unnecessary and may lead to diabetes and an increased cardiovascular risk; causing more damage than good.
In summary, Statins are recommended for treatment in those with CVD and those at a 20% 10year risk of CVD, and in these patients there is an apparent strong therepeutic benefit. But in patients at a lower risk, the controversy gains weight and the benefits may be surpassed by the risks of Rhabdomyolosis and type II diabetes. At the end of the day, the decision to take a statin should come down to the prescriber and healthcare professionals assessing the risk-benefit balance of each individual patient. Patients should not be deterred from using statins if they have been recommended by a doctor and are at high CVD risk and pharmacists can play a key role in reassuring patients about the efficacy of statins; explaining the risk-benefit balance to patients to ensure they do not allow inaccurate public claims preventing them from taking a potentially life saving drug.
I conclude that Statins are the Margaret Thatcher of drugs. As a leading class of drug on the market, they appear to get results, but the method, cost and validity of their achievments will always be surrounded by a cloud of controversy, with some groups championing them and others calling for an end to their time on the market.