The human condition: Hyperventilation: the new argument about asthma

Is 'over-breathing' a cause or a symptom? Jerome Burne reports

Breathing. What could be easier? Expand the lungs to draw in the life-giving air, squeeze them to push the waste products out. Of course, if you've got asthma the whole process can become agonizing, but the principle remains the same. Or does it? Last week a storm blew up over the apparently simple matter of what exactly happens when we breathe.

First, there was the publication of a book setting out a radical new approach to asthma. The big idea behind Alexander Stalmatski's Freedom from Asthma is that asthmatics should breathe less. No matter that when an attack strikes, each breath can seem like your last. In general, the problem asthmatics have, Stalmatski claims, is that they over-breathe. The subtitle - "Buteyko's revolutionary treatment" - points to the book's exotic origins. The theory is the work of Russian physiologist Konstantin Buteyko.

The Buteyko method has been on offer here for a couple of years and can boast a pile of testimonials. ("I've stopped taking all my drugs and I'm enjoying long walks for the first time in years"). In fact, we already have something very similar in this country. What the Buteyko method calls "over-breathing", we call hyperventilation syndrome (HVS). And after a scathing article in the New Scientist suggesting that it may be fantasy, this has been a bad week for HVS.

Most people know about hyperventilation in connection with panic attacks. You get too stressed and anxious and start breathing too fast and this in turn makes you feel dizzy and odd. One cure is to breathes into a paper bag.") The reason breathing too much makes your muscles go stiff and your fingers tingle is that it lowers the amount of carbon dioxide in your blood, which alters its chemistry, which, in turn, makes muscles and nerves behave differently. The paper bag brings the CO2 level up again.

Now, New Scientist isn't saying that paper-bag cases are having a fantasy; what happens to them is all too real. What is under attack is the idea that there is something called a hyperventilation syndrome (HVS), caused by regularly breathing too much, which has been linked with various chronic diseases including asthma. "Some researchers have placed their faith in HVS ahead of empirical science," declares the magazine.

The grand old man of British hyperventilation is Dr Claude Lum. He made the logical leap more than 30 years ago that if breathing too much can have such dramatic effects in the short term, it might have even more serious effects on someone who hyperventilates all the time. In a faxed reply to questions, Dr Lum declared that while there was no agreement on the definition of asthma, he believes that a major cause of asthma is hyperventilation. What's more, he writes, at least one major text book supports him. So, the Buteyko method, which claims to teach patients how to lower their breathing rate within a week, seems to have some scientific support. However, Dr Lum cautions, "There is much more to the treatment of asthma than just breathing."

But at King's College school of medicine, where Dr William Gardner is a senior lecturer in the thoracic department, the approach to HVS and Buteyko is very different. "There is no mystery about what asthma is," says Dr Gardner. "It is a disease mainly caused by an inflammation of the airways and perfectly treatable with inhaled steroids." Hyperventilation syndrome was a red herring. "Asthmatics may hyperventilate but that's because of their asthma, not the other way round." As for the Buteyko method, it certainly wouldn't do any good and might well be harmful. "Anything that stops people getting proper treatment with steroids could be dangerous," he said firmly. "What's more, trying to change your breathing settings is not a good idea. Your body does a very good job of it quite automatically."

In reply, Dr Lum declared that, "When I was in charge of the Respiratory Department at Papworth, I routinely measured carbon dioxide in the blood of asthmatics and found it 10 per cent to 15 per cent lower than normal. In other words, evidence of hyperventilation." So, how could two respiratory experts disagree so profoundly? "I will just state two facts that are in the public domain," says Dr Lum. "Dr Gardner has a fellowship from the Wellcome Foundation and Wellcome earn over pounds 1 billion a year from supplying asthma drugs."

Dr Gardner, in turn, was adamant that there is absolutely no connection between Wellcome, the charity and the drug company. "I don't hold some eccentric view, my position is simply what all good respiratory physicians believe. Dr Lum has been out of proper medicine for 20 years; he just isn't up with what is going on."

So, are we just seeing another alternative theory coming under the big guns of organised science? Not exactly. What has been interesting about this week is that it has revealed a genuine split in the medical community over something as basic as what happens when we breathe. A key plank in the New Scientist's argument was a study published last year by some Dutch researchers, led by Hellen Hornsveld. The conventional way of testing for HVS is to ask a patient voluntarily to hyperventilate for a few minutes and then ask them if they experienced some of the symptoms they had been complaining of. Hornsveld tested a group of people twice - the first time in the usual way and secondly with extra carbon dioxide being pumped into their blood. As far as their body chemistry was concerned, the second time round they weren't actually hyperventilating. However, the subjects reported much the same symptoms both times. The implication was that the diagnosis of HVS wasn't based on anything real.

The conclusion has divided the prestigious International Society of the Advancement of Respiratory Psycho- physiology, of which Hornsveld is a member. Other members, such as Professor Ronald Ley of the State University of New York, Albany, have dismissed the study as shoddy and riddled with flaws and posted a detailed rebuttal in the Society's site on the Internet.

That still leaves Buteyko out on left field (even HVS believers describe him as a "maverick" and his ideas as "untested"). For anyone wanting a definitive statement on HVS, the best advice is probably, don't hold your breath.