The research, published in the Journal of the Royal Society of Medicine, confirms previous studies that prolonged sitting at work represents an important risk factor for developing blood clots that may present even more of a risk than long haul flights.

"The current study represents a major advance from previous work in that it is a case-control study with considerably greater scientific merit than the previous case series," says Professor Richard Beasley, the study leader from Wellington Hospital (CCDHB) in New Zealand.

The new study identified that prolonged sitting at work was associated with a two-fold increased risk of developing a deep vein thrombosis (DVT) or pulmonary embolism (PE). Moreover, both the maximum number of hours seated at work, as well as the number of hours seated without getting up, were associated with an increased risk of both DVT and PE.

The authors of the study recommend that with the current state of knowledge it would seem prudent to advise all people who commonly sit for prolonged periods at a computer to undertake frequent leg and foot exercises and to take regular breaks away from their computer.

These findings were similar to the situation with travellers thrombosis in which both the duration of the flight and immobility during the flight having been shown to be associated with an increased risk of DVT and PE.