Rollingthunder
11th May 2001, 06:08
One in 10 people who travel on long-haul flights develop blood clots, according to scientists.
The London researchers revealed that 40 times more people suffered deep vein thrombosis (DVT) after long-haul flights than
previously thought.
But many of these clots are "symptomless" and do not go on to develop into larger and potentially fatal clots.
Wearing special compression stockings, given out by some airlines, has been found to reduce the risks.
But the results are bound to raise concern among passengers.
The latest study, published in The Lancet, has already provoked controversy with scientists disputing the high number of cases
found by consultant surgeon John Scurr and his team.
An international meeting of scientists, aviation experts and air authorities in March launched an investigation into the number of
DVT deaths following long-haul flights.
Victims
About 10 people a year die from blood clots in the lungs, like Emma Christofferson, 28, who died after a 20-hour flight from
Australia.
And relatives of 14 UK DVT victims have launched a multi-million law suit against the airlines concerned.
Mr Scurr, of the Middlesex and University Hospitals, London, said his team had used extremely sensitive ultrasonographic
assessment which enabled them to pick up more cases.
His team studied over 200 passengers who had travelled on flights of eight hours or more.
Half were given the special stockings and showed no symptoms - 10% of the others did show clots in their calves.
"What we are doing is picking up the small clots, some will just go away, but others like seeds will germinate and become bigger
clots."
Mr Scurr said there was no-one who could not fly, even those who had previous problems.
He said following medical advice and using stockings should cut the risk of clots and that the airlines were working with
scientists to cut risks.
Mr Scurr said: "The airlines have been working with us for some time now.
"They are very familiar with these results and are giving passengers advice.
What we are doing is picking up the small clots, some will just go away but others like seeds will germinate and become
bigger clots
John Scurr
consultant surgeon
"For the majority of people, though, there is no risk."
In a commentary piece also in the Lancet, Dr Jack Hirsh from McMaster University in Ontario, Canada, said more detailed and
extensive studies were needed before firm conclusions could be drawn.
"What is needed are rigorously designed and adequately powered studies to resolve the issue.
"It would be premature to legislate that airlines change the seating configuration or introduce other costly procedures until there
is more information on the extent of the problem and on the effectiveness of much simpler preventative measures."
Or --- No one's proven anything yet!
The London researchers revealed that 40 times more people suffered deep vein thrombosis (DVT) after long-haul flights than
previously thought.
But many of these clots are "symptomless" and do not go on to develop into larger and potentially fatal clots.
Wearing special compression stockings, given out by some airlines, has been found to reduce the risks.
But the results are bound to raise concern among passengers.
The latest study, published in The Lancet, has already provoked controversy with scientists disputing the high number of cases
found by consultant surgeon John Scurr and his team.
An international meeting of scientists, aviation experts and air authorities in March launched an investigation into the number of
DVT deaths following long-haul flights.
Victims
About 10 people a year die from blood clots in the lungs, like Emma Christofferson, 28, who died after a 20-hour flight from
Australia.
And relatives of 14 UK DVT victims have launched a multi-million law suit against the airlines concerned.
Mr Scurr, of the Middlesex and University Hospitals, London, said his team had used extremely sensitive ultrasonographic
assessment which enabled them to pick up more cases.
His team studied over 200 passengers who had travelled on flights of eight hours or more.
Half were given the special stockings and showed no symptoms - 10% of the others did show clots in their calves.
"What we are doing is picking up the small clots, some will just go away, but others like seeds will germinate and become bigger
clots."
Mr Scurr said there was no-one who could not fly, even those who had previous problems.
He said following medical advice and using stockings should cut the risk of clots and that the airlines were working with
scientists to cut risks.
Mr Scurr said: "The airlines have been working with us for some time now.
"They are very familiar with these results and are giving passengers advice.
What we are doing is picking up the small clots, some will just go away but others like seeds will germinate and become
bigger clots
John Scurr
consultant surgeon
"For the majority of people, though, there is no risk."
In a commentary piece also in the Lancet, Dr Jack Hirsh from McMaster University in Ontario, Canada, said more detailed and
extensive studies were needed before firm conclusions could be drawn.
"What is needed are rigorously designed and adequately powered studies to resolve the issue.
"It would be premature to legislate that airlines change the seating configuration or introduce other costly procedures until there
is more information on the extent of the problem and on the effectiveness of much simpler preventative measures."
Or --- No one's proven anything yet!