The medical response has been to develop more drugs and get people on to them sooner - annual sales of inhalers now top 18 million. A recent pilot project in Kent looking for asthma among children found that for every one known case there was another undiagnosed. All of the children were put on drugs. Many parents are not happy with this approach, but there is no alternative.
Or rather there is, but it is being firmly ignored. Last year a couple of newspaper stories described a radical new treatment for asthma which simply involved learning a new breathing pattern. Scores of patients reported that they no longer needed to use drugs and had much better control over their symptoms.
One satisfied customer was the MP Jonathan Aitken, who says it reduced his symptoms and made drugs unnecessary. Another was Dr John Stanley of the National Public Health Laboratory, who said, "It changed my life. Before, I could barely walk up stairs now I can manage a 10-mile hike. I was using my puffer four times a day as well as steroids and now I'm off all drugs."
You might think that such results would be welcomed by the National Asthma Campaign - motto: "getting your health back". After all, they are dedicated to relieving the plight of asthmatics and most sufferers worry about the quantity of drugs they have to take. But the campaign's response to any queries about the Buteyko method, as it is known, is the following statement: "We would strongly advise people with asthma not to pay several hundred pounds to be taught a method of treatment that is of unproven benefit." The reason they give is that they are not aware of any scientifically validated trials of the method.
This claim makes Chris Drake, a Buteyko practitioner, furious. "Why do they say it has not been adequately researched when there has been a double- blind clinical trial in Australia and the interim results have been written up in an Australian medical journal? They were the best in terms of help for asthmatics ever published."
The Buteyko method - it was developed by the Russian physiologist Professor Konstantin Buteyko - involves no mystical concepts, it is firmly based in Western physiology and yet getting it taken seriously by a medical establishment rooted in the drug culture has proved extraordinarily difficult.
The technique does make one revolutionary claim: that the problem asthmatics have is that they breathe too much. The reasoning is this. We all know that we breathe in oxygen, which passes through the lungs into the blood stream, and breathe out the waste gas carbon dioxide (CO2). What is not so familiar, although it is in all the physiology text books as the Verigo- Bohr effect, is that we actually need CO2 in the lungs for the oxygen to pass efficiently into the blood.
The body needs a concentration of about 6 per cent CO2 and the amount in the air is only about 0.03 per cent. The body's solution has been for the alveoli - the tiny air sacs in the lungs - to act as CO2 accumulators. But because CO2 is a very light gas, heavy breathing has the effect of diluting the CO2 stored in the air sacs.
Professor Buteyko tested thousands of asthmatics and found that all of them were over-breathing. The optimum amount is around 5 litres per minute, but asthmatics were breathing two, three or even four times that amount. The result is that the CO2 levels go down and the body responds by constricting the airwaves - its way of saying, "Stop breathing so much!" The essence of the Buteyko method is that by reducing the level of breathing, the CO2 levels rise and the airways open.
It is an interesting theory and would seem easy enough to test. But it hasn't quite turned out like that. Five years ago a Russian Buteyko trainer, Alexander Stalmatsky began teaching in Australia, which has one of the highest proportions of asthma sufferers in the world. Since he started, some 6,000 people have learnt the technique, including former Australian squash champion Karen Clonda, and media interest has been considerable. One of the most thorough TV programmes was made by Peter Wilkinson, an investigative journalist with his own slot, A Current Affair, for Channel 9.
"I'm a pretty sceptical bloke," says Wilkinson, "but this technique really seemed to work." His team followed two classes of 30 people each for about three months and found the majority enjoyed considerable benefit. They also contacted 100 patients from the Buteyko centre's records. About 60 to 70 per cent told the researchers they were much improved. "But when we put all of this to the official asthma people they refused to budge an inch."
The interest generated by media coverage led to the setting up of a trial, which was run by Professor Charles Mitchell of Queensland University. Forty middle-aged, chronic asthmatics, who had had asthma for an average of 23 years, were divided into two groups. The control group - average age, 43 - were given physiotherapy, taught standard breathing techniques and given instruction on drug use. The others - average age, 48 - were taught the Buteyko method.
Six weeks after the trial the Australian Doctor ran a story entitled "Doctors Gasp at Buteyko Success". The preliminary findings were that while there was no change in the control group, the Buteyko group had reduced their use of beta agonists (bronchodilators) by 90 per cent and reported an improvement in their symptoms. Eight months later the improvement not only continued, they had also reduced their steroid intake. The method seemed to be vindicated.
In fact it was only the beginning of a bitter debate that is still going on, even between the authors of the study. Professor Mitchell describes the results as impressive, but only superficially. The crux of the matter for him was that the trial provided no objective proof that the patients were better. Even though they took fewer drugs and said they felt better, the FEV1 test, a routine test to assess the severity of asthma, showed no change.
What's more, the claims about CO2 didn't stand up either. "We measured CO2 levels," says Professor Mitchell, "and found no correlation between the patients whose CO2 levels had gone up the most and the ones who improved the most. So it looks as though CO2 is not the relevant factor here."
All of which is a gross misrepresentation of what actually happened at the trial, according to Tess Graham, co-author of an as yet unpublished paper and the trainer for the Buteyko group. "It is such rubbish to say the drug reduction was due to some psychological effect," she says, "I must be an absolute genius if I can persuade people who have been taking a drug for more than 20 years to stay off them just because I say so."
Graham, a physiotherapist who first became involved when her own asthmatic children lost all their symptoms after learning the technique, has now trained more than 700 patients. She was furious that Mitchell failed to mention anything about the over-breathing results. "They weren't even going to test for hidden hyperventilation to begin with," she says, "even though it is the central point of the Buteyko method. We measured the patients in both groups and found they were all breathing, on average, 14 litres per minute, three times the healthy amount."
Afterwards the Buteyko group was down to an average of 9.6 litres while the others had not changed. "What's most important, though, is that those who reduced their breathing the most also reduced their drugs the most. This shows that there's a logical link between the Buteyko method and a reduction in drug use. Nobody is telling the asthma foundations that."
The asthma establishment does not even consider over-breathing to be a factor in asthma. The British National Asthma Campaign says, "there is no evidence that a person with stable asthma is over-breathing". This finding, if it is replicated, suggests they are wrong.
Given their share of positive results from the trial and the mound of anecdotal reports of success, it hardly surprising that the Buteyko supporters believe they are being ignored and the results played down.
"The Asthma Foundation is happy to support research into anything that may contribute to asthma - dust mites, dog hairs, fish oil, lack of lipid acids," says Chris Drake, "but their basic principle is that asthma is incomprehensible and incurable. Come up with a cure and they get worried. On the day our first results came out in Australia the Asthma Foundation put out a story about how a new study had shown margarine might be a factor. Margarine! If we are right a lot of research projects will go down the tube."
Chris Drake runs courses in the Buteyko method at the Hale Clinic, 7 Park Crescent, London W1N 3HE, 0171-631 0156. Courses are also available at The Kingston Natural Healing Centre, 40 Eastbury Road, Kingston KT2 5AN, 0181-546 5793.
THE BUTEYKO METHOD: LEARNING `THE CONTROLLED PAUSE'
Chris Drake's sessions at the Hale Clinic in London begin with a "controlled pause". Anyone can do it, he says, and it will tell you if you are over-breathing. Breathe in gently for two seconds, out for three seconds, then hold your breath until it becomes uncomfortable. Less than 10 seconds and you have a serious health problem, less than 25 and you are unhealthy, 30 to 40 is OK and 60 plus excellent.
On the second day, the hard work of improving the controlled pause begins. Participants fight the urge to breathe in and gradually, the time they can manage increases. Chris Drake talks about the foods to be avoided that encourage deeper breathing - caviar, crab, milk, fish and chicken. Everyone is given breathing exercises to do three times a day.
By the third day, results are starting to appear. Some report having the first good night's sleep for years, others are already using less medication. By the last evening those who could only manage a 10-second pause at the start can do 15 or 20 seconds and everyone is given a personal programme of exercise they can use to bring asthma attacks under control.