Deep vein thrombosis (DVT) or clot formation is on the rise among patients who suffer from acute illness. The team led by Dr Liam Smeeth, from the London School of Hygiene and Tropical Medicine, said that they wanted to look at whether infection could trigger DVT or pulmonary embolisms.
The Lancet studied and analyzed the 3 million GPs' records and found 7,278 people suffer from DVT and 3,755 a clot on the lung. The London team found those who had suffered either respiratory or urinary infections were nearly twice as likely to develop blood clots two weeks later. They suggested that the clots could have been caused by inflammation in the blood vessel linked with infection. Statistics show that DVT contributes to about 10% of deaths among hospital patients each year. Usually they occur in the leg veins but can also break off and lodge in the small vessels in the lung.
If this occurs the condition is called a pulmonary embolism. This can be fatal if not treated properly. Participants who had suffered previously from either acute infections in the urinary tract or in the respiratory system such as influenza, bronchitis and pneumonia were studied. They found that during the infection there was no impact on the risk of developing blood clots. But after several weeks the risk appeared to double. Dr Smeeth said that the clot formation could be attributed as an effect of the inflammatory response due to the infection.
DVT has commonly been associated with people sitting still in cramped conditions on aeroplanes and also dehydration associated with the infection could thicken the blood. Hence this risk factor should be considered along with other risk factors such as cancer and pregnancy. Dr David Keeling, Royal College of Physicians advisor and expert in DVT at the Oxford Haemophilia Centre and Thrombosis Unit, said the research was interesting. He also said that the activation of the coagulation system or excessive clotting of the blood by inflammation is the key factor in causing DVT.