This chronic disease tends to develop slowly, with symptoms of fatigue, shortness of breath and swelling in the legs. The underlying cause is a loss of pumping capacity by the heart, which may be due to persistent high blood pressure, irregular heartbeats, hardened arteries, a previous heart attack, lung disease or thyroid gland problems.

Early on, the body compensates by increasing the heart rate and even the size of the heart. However, as the heart weakens, fluid collects in the lungs (hence the word ‘congestive’) or is trapped in the circulatory system, causing swelling of the blood vessels and organs such as the liver.

Heart failure is now the leading cause of hospitalisation in those over 65 - and the problem is getting worse by the year. Experts tell of a 'growing epidemic of CHF' (Cardiol Clin, 2001; 19: 547-55), particularly over the last 20 years. In the US, nearly five million people suffer from heart failure; in the UK, it is believed to affect 1 per cent of the population - or around 500,000 people - at any given time. Some experts find this CHF epidemic puzzling, given the fall-off in other heart diseases (MMWR, 1994; 43: 77-81). Others warn that CHF is 'highly lethal', killing over 80 per cent of men within six years of diagnosis (Am Heart J, 1991; 121: 951-7).

Mortality rates like these have been one of the reasons why health authorities are prepared to spend huge amounts of money on statins, the so-called miracle drugs that are meant to prevent heart disease.

The miracle of statins With most of the world’s major pharmaceutical companies offering a statin, this is now the biggest drug sector - worth a staggering $20 billion each year. Introduced less than 20 years ago, they have become the most profitable drugs in the history of medicine.

Statins don’t cure; they reduce cholesterol levels in blood to below the figure thought to cause heart disease. As such, statins are primarily prescribed as preventative medications and often given in perpetuity. But these ‘patients’ don’t have a true illness; they are simply those who have a particular lab-test reading - and may have no symptoms whatsoever.

Moreover, the cholesterol-heart disease connection is still largely only theoretical, and not always borne out in practice: for example, 50 per cent of people who die from heart attacks don’t have high cholesterol.

So, according to the best analysis, statins may only prevent some heart conditions - and that’s assuming they work. Nevertheless, cardiologists - especially those in the US - recommend that at least half of the adult population should be permanently taking statins. Even in the cash-strapped NHS, British GPs are urged by drug companies to give statins to anyone whose cholesterol levels fall outside of the recommended ‘target’ values.

But statins are now increasingly coming under fire. First, although marketed as safe, bitter experience has revealed serious side-effects (see box, p 2). But the major concern is that, although statins may lower cholesterol by as much as 30 per cent, this does not translate into any significant prolongation of life - which is why they are given in the first place.

Statins unmasked The evidence that statins don’t deliver the goods has been steadily accumulating over the past decade. Keen-eyed medical statisticians have pored over the data from drug company-sponsored clinical trials, and found some interesting facts hidden behind the headlines.