A recent study found that anxiety or depression disorders can increase the risk of deep vein thrombosis, a serious blood clotting condition by nearly 50 per cent. The study was conducted by researchers at the Massachusetts General Hospital, US.

They analysed their dataset of over 1.1 lakh participants to understand link the between anxiety and depression and the risk of deep vein thrombosis. A smaller group of 1,520 people underwent brain imaging. Brain imaging showed that increased stress-related activity in the brain, along with inflammation - because of the mental illnesses - were driving up the risk of deep vein thrombosis, in which a blood clot forms in a deep vein.

Deep vein thrombosis (DVT) happens when a blood clot (thrombus) forms in one or more of the deep veins in the body. This usually happens in the legs, however, it can happen in any part of the body. Deep vein thrombosis can cause leg pain or swelling. Sometimes you might not have any noticeable symptoms.

Mayo Clinic says that DVT can be serious because blood clots in the veins can break loose. The clots can then travel through the bloodstream and get stuck in the lungs, blocking blood flow (pulmonary embolism). When DVT and pulmonary embolism occur together, it’s called venous thromboembolism (VTE).

For the study, the participants were followed over a period of over three years. 1,781 participants (1.5 per cent) were found to develop the blood clotting condition. The researchers found that while having either anxiety or depression disorder was associated with roughly a 50 per cent chance of developing deep vein thrombosis, having both mental illnesses was associated with a 70 per cent chance of developing the clotting condition.

The study was published in the American Journal of Hematology. The authors wrote, “The results, thus, identify anxiety disorders and depression as potent risk factors for deep vein thrombosis and identify modifiable mechanisms that mediate this association.”

The participants were typically aged 58 years and 57 per cent were women. Of the whole group, 44 per cent had a history of cancer.

However, adjusting for cancer, a risk factor for depression and blood clotting in veins, did not alter the results, the authors said.

The authors said that given the link between anxiety disorders, depression, stress-related neural activity (SNA) and the subsequent development of DVT, future studies should investigate the impact of reducing SNA on this pathway.

“Specifically, future studies could test whether targeting SNA with interventions that may reduce SNA (i.e., exercise and stress reduction techniques) will reduce the risk of incident DVT and even the risk of recurrent DVT,” the authors added.