Statins. Photo: Getty
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Why the stats about statins don't tell the whole story

For those without the relevant risk factors, statins aren't the wonder-pill they've been sold as by the media.

Maggie came hot-foot from a “health check” where she’d had her cholesterol measured. “Six point two!” she told me. “The nurse said that’s high.” She sounded rather spooked. “I’d like you to give me a statin.”

I’ve known Maggie for years. She’s a sensible academic in her early fifties. She’d done enough googling to learn that a “high” cholesterol means you are “at risk” of cardiovascular disease (CVD) – heart attacks and strokes – and that statins lower cholesterol and reduce CVD risk by 25 per cent. Her request for treatment made perfect sense to her . . . except she had fallen for the same myth that leads to several million people in the UK swallowing a statin every day for no good reason at all.

Focus for a moment on that 25 per cent risk reduction. If you’re at high risk of something nasty, then lopping off a quarter of that risk makes sense. The people at greatest risk of heart attacks and strokes are those who have previously suffered one. Giving statins to these patients (secondary prevention) does convey modest benefits. If you take 100 heart attack survivors and get them to take a statin for five years, you’ll save one life, prevent two or three non-fatal heart attacks, and avert one stroke. That is worthwhile, even if the statins will fail to prevent at least 15 other heart attacks/strokes, and will cause two patients to develop diabetes, and provoke muscle weakness in ten others. Notice, though: 95 per cent of these highest-risk patients will derive absolutely no benefit from their five years of statin consumption.

Come back to Maggie. Using a statin on someone without existing CVD is termed primary prevention. Maggie has no other risk factors (high blood pressure, smoking, diabetes, and so on) and so her chance of developing heart disease is very low. In Maggie’s case, because her risk is so small to start with, a 25 per cent reduction is minuscule and meaningless. You’d have to treat hundreds of Maggies for years on end to hope to make a jot of positive difference to one of them, and the side effects from statins (we’re still discovering what these are) will far outweigh any putative benefit.

There are large numbers of people just like Maggie who are taking statins and who should come off the tablets. But what about individuals at greater risk – people with high blood pressure or obesity, or smokers? Is there a level of risk at which primary prevention is worthwhile? For some time the UK’s National Institute for Health and Clinical Excellence (NICE) has suggested a threshold of 20 per cent risk over ten years.

At first glance, the trial data does suggest a marginal impact at this sort of level: roughly two heart attacks/strokes are averted among 100 people treated for five years. But, crucially, death rates are not altered; no lives are saved by using statins. This probably reflects the harm also caused by statins, and how any small reduction in CVD is negated by disability and death from other causes.

Taking up regular exercise, or adopting a Mediterranean diet, reduces CVD risk by degrees comparable with statins – in the case of diet, substantially more so. If someone smokes, quitting is similarly helpful. What’s more, once one has adopted these lifestyle changes, statins become virtually redundant. Lifestyle modification is also cheap; there are very few harms besides. And, unlike with statins, these measures protect against other causes of death and disability, such as cancer and the frailties of advancing age. Oh, and they’re good for mental health, too.

This February, NICE initiated a consultation on halving its primary prevention threshold to 10 per cent risk. If achieved, this would add hugely to the six million people in the UK who take statins on prescription. Rather than exacerbate our statin fetish, NICE could design simple decision aids that would help doctors understand the more effective improvements that lifestyle changes can bring to health and well-being – and which would illustrate these benefits to patients.

Once we’d talked things through, Maggie resolved to start attending the university gym a few times a week. She decided to forget the statin prescription, too. As a nation, we’d do well to try the same. 

This article first appeared in the 26 February 2014 issue of the New Statesman, Scotland: a special issue

Yu Ji/University of Cambridge NanoPhotonics
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Nanoengine evolution: researchers have built the world’s smallest machine

The engine could form the basis of futuristic tiny robots with real-world applications.

Richard P Feynman, winner of the Nobel Prize in Physics in 1965, once remarked in a now-seminal lecture that a time would come where we would “swallow the doctor”. What he meant, of course, was the actualisation of a science-fiction dream – not one in which a universal cure-all prescriptive drug would be available, but one in which society would flourish through the uses of tiny devices, or more specifically, nanotechnology. 

First, a quick primer on the field is necessary. Nanoscience involves the study and application of technologies at an extremely tiny scale. How tiny, you ask? Given that one nanometre is a billionth of a metre, the scale of work taking place in the field is atomic in nature, far beyond the observational powers of the naked human eye.

Techno-optimists have long promoted potential uses of nano-sized objects, promising increases in efficiency and capabilities of processes across the board as a result. The quintessential “swallow the doctor” example is one which suggests that the fully-realised potential of nanotechnology could be applied to medicine. The idea is that nanobots could circulate our bodily systems in order to reverse-engineer the vast array of health problems that threaten us.

It’s natural to be sceptical of such wild aspirations from a relatively young field of study (nanoscience unofficially began in 1959 following Feynman’s lecture “There’s Plenty of Room at the Bottom”), but associated research seems to be gaining widespread endorsement among prominent scientists and enthusiasts. Ray Kurzweil, Director of Engineering at Google, thinks a booming nanotechnology industry is crucial in the creation of a technological singularity, while futurist and viral video philosopher Jason Silva believes the technology will help us cure ageing.

The high-profile intrigue surrounding nanotechnology means that word of any significant developments is certain to stimulate heightened interest – which is why researchers’ achievement in building the world’s tiniest engine this month is so significant.

Reporting their results in the journal Proceedings of the National Academy of Sciences, the University of Cambridge researchers explained how the nanoengine was formed and why it represented a key step forward in the transition of the technology from theory to practice.

The prototype nanoengine is essentially composed of charged particles of gold, bound by polymers responsive to temperature in the form of a gel. The engine is then exposed to a laser which beams and heats the device, causing it to expel all water from the polymeric gel. The consequence of this is a collapsing of the gold particles into an amalgamated, tightened cluster. Following a period of cooling, the polymer then begins to reabsorb the water molecules it lost in the heating process, resulting in a spring-like expansion that pushes apart the gold particles from their clustered state.

"It's like an explosion," said Dr Tao Ding from Cambridge's Cavendish Laboratory. "We have hundreds of gold balls flying apart in a millionth of a second when water molecules inflate the polymers around them."

The process involved takes advantage of the phenomenon of Van der Waals forces – the attraction between atoms and molecules. The energy from these forces is converted into elastic energy, which in turn is rapidly released from the polymer. "The whole process is like a nano-spring," said Professor Jeremy Baumberg, who led the research.

Scientists have been tirelessly working towards the creation of a functional nanomachine – one which can effortlessly swim through water, gauge its surroundings and communicate. Prior to the research, there was a difficulty in generating powerful forces at a nanometre scale. These newly devised engines, however, generate forces far larger than any previously produced.

They have been named “ANTs”, or actuating nano-transducers. "Like real ants, they produce large forces for their weight. The challenge we now face is how to control that force for nano-machinery applications," said Baumberg.

In an email exchange with New Statesman about the short-term and long-term goals in bringing this engine closer to a practical reality, Baumberg said: “It allows us for the first time, the prospect of making nano-machines and nanobots. The earliest stage applications we can see are to make pumps and valves in microfluidic systems. Microfluidic chips are really interesting for synthesising pharmaceuticals, biomedical sensing and separation, as well as many other biochemical processes.

“But all pumps and valves currently need to be made with hydraulics, so you need a pipe onto the chip for each one, limiting strongly the complexity of anything you do with them. We believe we can now make pumps and valves from the ANTs which are each controlled by a beam of light, and we can have thousands on a single chip. Beyond this, we are looking at making tiny nanomachines that can walk around, controlled by beams of light.”

The embedding of nanobots into all facets of culture is still a long way off, and researchers will need to find a way of harnessing the energy of nanoengines. However, the prospect of one day seeing the fruition of nanorobotics is worth all the patience you can get. The tiniest robot revolution has just begun.