Prior to April 2001 there had been many reports relating to incidents of deep vein thrombosis (DVT) in people who had recently flown long distances. The reports were interesting because the people were otherwise healthy and not at a high risk of developing a DVT in normal circumstances.

The problem became known as "Economy Class Syndrome" but the reports showed that this medical condition also occurred in passengers who had travelled in "Business Class".
A number of detailed studies looked at the reported incidents of DVT after flying or looked at patients suffering from DVT. However these studies were unable to establish a causal link between flying and an increased incidence of DVT.

Then in May 2001 Britain’s premier medical journal "The Lancet" published the results of the first objective study of flying and the incidence of DVT. A group of researchers from The Middlesex Hospital, London examined the veins and blood from 231 volunteers before they embarked on their holidays involving long haul flights (more than 8 hours). On their return to London the volunteers were re-examined. The research was headed by John Scurr a vascular surgeon, thrombosis expert and aviator and Professor Sam Machin a haematologist.

The volunteers were split into two groups, one group travelled as normal the other group wore mediven® travel compression socks. On their return the volunteers were examined using ultrasound and it was found that in the first group of 116 volunteers 10% of the passengers had a thrombosis in the deep veins of their legs. The travellers received immediate treatment without which the condition may have become more serious. However, a single mild incidence of deep vein thrombosis can predispose to further incidents of a more serious nature in the future. In the second group of 115 volunteers wearing mediven® travel socks not one person showed any thrombosis in the deep veins of the legs.

The study showed that long haul flying increased the incidence of DVT in healthy people but wearing mediven® compression socks significantly decreased the chances of developing a DVT whilst flying. mediven® compression socks remain one of the few ‘flight socks’ to be clinically proven to be effective.

(J Scurr et al. A randomised trial to assess the incidence of asymptomatic DVT and prevention by graduated compression stockings. Lancet 2001.)