People with the lives of passengers in their hands are hiding the fact that they have sleep problems because they fear for their jobs, warned Professor Neil Douglas, director of the Scottish National Sleep Laboratory in Edinburgh.
He told the annual meeting of the British Sleep Society in London: "The traditional approach has been to bin patients as people who are either lazy or who don't have a problem. I have had air-traffic controllers, bus drivers and lorry drivers as patients. All of them have admitted that they have fallen asleep doing their job."
But, he said, such people can be successfully treated and carry on working.
Air-traffic controllers undergo the same rigorous medical checks as pilots to spot any problems that might pose a hazard to the public. Their hours are also carefully structured to ensure maximum alertness - no more than two hours on duty without a break, no more than two successive night shifts, no shifts longer than 10 hours, or gaps between spells of duty of less than 12 hours.
Spokesmen for both the Guild of Air Traffic Controllers and the Civil Aviation Authority said they had never heard of controllers suffering sleep disorders. The spokesman for the CAA said: "We would certainly take it seriously if anyone did have a problem. We have our own medical department which would certainly be able to offer help to someone with a sleeping disorder." He said he failed to see how a controller could fall asleep and not be noticed, because they never worked alone.
The most serious sleep disorder is narcolepsy where the patient is liable to fall asleep unexpectedly at any time. Insomnia caused by stress and depression is a common problem, and sleep apnoea prevents patients breathing normally at night so that they continual wake up and are exhausted the next day.
Professor Douglas said that daytime sleepiness was a huge problem, affecting about one-in-25 middle-aged men and one-in-50 middle-aged women. "There is evidence that one-quarter to one-fifth of all motorway accidents are caused by the driver falling asleep at the wheel ... these accidents have been shown in one study to be the commonest cause of fatalities," he said.