Mass medication: A large dose of hit-and-miss

A trend of doctors to treat populations rather than individuals can often do more harm than good.

Sir William Osler, the ''father of modern medicine'', said that what distinguished humans from animals was the desire to take medicine.

Osler died in 1919, but, like most of his brilliant aphorisms, it is still true, with the added development that now many of us take pills even if there's nothing wrong with us. He also thought one of the first duties of the physician was to educate people not to take medicine. That idea, that medicines are potentially dangerous and should be avoided if possible, has gone out the window - which is a pity.

We're now seeing a radical extension of the doctrine that ''prevention is better than cure'', with damaging consequences. So, where prevention once meant living well, exercising, not smoking, having routine vaccinations, now it entails chucking strong medication at whole populations.

This is population medicine as opposed to individualised medicine. Instead of the doctor looking at each patient who comes into the consulting room, taking a history and providing treatment tailored to that person, you medicate a population, or ''epidemiological cohort'', in the jargon.

Lowering the population risk is thought to be worth doing, even though the awkward fact is that most of the patients do not need the pills, will never benefit from them and may be harmed by them. This is a departure from established notions of preventative medicine. But it allows drug companies, who try to influence public health policy, to present their products as serving a protective function. And that does wonders for their bottom line.

Another example cropped up last week. Britain's NICE, the National Institute for Health and Care Excellence, the government body that guides prescribing habits in the National Health Service, proposed that the threshold be halved for offering statins to people, so they're given to even


more patients. These cholesterol-lowering compounds are already one of the most prescribed drugs in the GP's formulary, and one of the most frequently given to people who are well. I am on a low dose of atorvastatin, though I'm not in the highest-risk group.

Clearly, they do benefit people who have had a heart attack or stroke; whether those who just score highly for risk factors will benefit, on the other hand, is less certain.

A meta-analysis in the Archives of Internal Medicine found no evidence for the benefit of statin therapy in patients who had not had serious heart disease. And for every 136 people who take statins, one will get a case of liver injury. Other side effects (admittedly, often rare) include acute renal failure, muscle aches and cataracts.

Population medicine means that individuals are taking the risk of harming their health, on behalf of the other members of the population who might benefit.

And there's the cost of treating the side effects to consider. These are unquantifiable: in her excellent book The Patient Paradox, Glasgow GP Margaret McCartney tells the story of an elderly patient who suffered such painful muscle aches as a result of her statin treatment that she had given up going to tea dances, which were keeping her fit.

Not that statins are the only mass medication. Another is the ''polypill'', a mixture of three or four drugs designed to reduce population risk of heart disease. Every couple of years an enthusiast proposes that polypills should be dished out to everyone above a certain age. But obviously the more drugs you combine, the greater the risk.

The classic instance of a whole-population approach is fluoride in water. As Professor K.K. Cheng and others have pointed out in the British Medical Journal, there is precious little evidence that it does any good, whereas fluoride applied as toothpaste has been shown to prevent tooth decay.

Treating people as an undifferentiated mass like this seems an oddly crude approach, especially when you contrast it with the promise held out by gene therapies adapted to the individual's own make-up. Most of us, I would guess, still prefer the idea of the one-to-one consultation with a doctor who knows us a little. It is more humane, and more likely to work. Do we really want our highly educated GPs to act merely as robotic functionaries of the public health, handing out pills like Smarties?

There is a further problem with mass medication: the so-called ''healthy attender effect''. This is the observable fact that the ''worried well'' are most likely to take the tablets, but are at the lowest risk. The sick ones, who might actually benefit, are least likely to comply. The sort of maladies that statins and polypills are aimed at - cardiovascular disease and suchlike - are associated with poverty and lifestyle. Proper public health policy should address itself to these causes rather than spraying pills at the country.

I went on a statin after my GP looked at my high cholesterol figures and family history. After a discussion, weighing up the risks and benefits, we agreed that I should try it.

The decision was the product of traditional, personalised medicine. And that is as it should be. We are human beings, not epidemiological cohorts.

Daily Telegraph, London